Conference Proceedings Tagungsband - bdguss.de · Dienstag/Tuesday, 16.06.2015 Contents/Inhalt 13:15 Inorganic Core Sand: Decoring of Castings and Sand Reclamation ... Dr.-Ing. A

Conference Proceedings Tagungsband

GIFA-Forum NEWCAST-Forum

WFO Technical-Forum VDI – Technical-Forum

Conference Proceedings

sponsored by Foseco

Durchführung/ Organization

BDG Bundesverband der Deutschen Gießerei-Industrie

Hansaallee 203, D-40549 Düsseldorf

Telefon: +49 (0) 211 / 6871 – 338

Telefax: +49 (0) 211 / 6871 – 40338

E-Mail: [email protected]

www.bdguss.de

Messe Düsseldorf GmbH

Postfach 10 10 06, D-40001 Düsseldorf

Messeplatz, Stockumer Kirchstraße 61, D-40474 Düsseldorf

Telefon: +49 (0) 211 / 4560 – 01

Telefax: +49 (0) 211 / 4560 – 668


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Hansaallee 203, D-40549 Düsseldorf

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Verein Deutscher Ingenieure e.V.

VDI-Platz 1, 40468 D-Düsseldorf

The World Foundry Organization Ltd

Winton House, Lyonshall

Kington, Herefordshire

HR5 3JP, United Kingdom

3

GIFA-Forum Dienstag/Tuesday, 16.06.2015

Contents/Inhalt Page/Seite

GIFA-Forum 18

11:00 Energy Efficient Use of Medium Frequency Induction

Furnaces with Constant Power Range by Use of Power

Optimized Charging

Energieeffizienz in der Gießerei am Beispiel der

leistungsoptimierten Chargierung von Induktions-

tiegelöfen

Dr.-Ing. M. Rische*, Dr. E. Dötsch, Y. Yildir, R. Ibach,

ABP Induction Systems GmbH, Dortmund/Germany

11:30 A New Generation of Ceramic Foam Filters Providing

Real Opportunities for Cleaner Steel Castings

Die nächste Generation Stahlfilter für noch besseren

Guss

N. Child, Foseco International Limited, Tamworth/United

Kingdom

12:00 New Trends in Feeder Technology

Neue Trends in der Speisertechnologie

G. Brieger, Chemex GmbH, Delligsen/Germany

12:30 High Value Added Cast Parts - Advanced Feeding

Systems and Metallurgical Improvements

Gussteile mit hoher Wertschöpfung – Verbesserte

Speisungstechnik sowie metallurgische Verbesserungen

J. Prat*, ASK Chemicals España, Castro

Urdiales/Spain; G. Artola, J. Izaga, IK4-Azterlan,

Metallurgical Technical Centre, Durango/Spain

4


Contents/Inhalt

13:15 Inorganic Core Sand: Decoring of Castings and Sand

Reclamation

Anorganisch gebundener Kernsand: Entsanden von

Gussteilen und Regeneration des Kernsandes

Dr. U. Dinglreiter, R. Scheuchl GmbH, Ortenburg/

Germany

13:45 New possibilities of surface finishing for the die casting

industry

Neue Möglichkeiten der Oberflächenbearbeitung für die

Druckgussindustrie

I. Löken, Spaleck Oberflächentechnik GmbH & Co. KG,

Bocholt/Germany

14:15 Methods for Describing the Flow Behavior of Inorganic

Core Sand Material for the Production of Complex Cast

Components

Methoden zur Beschreibung des Fließverhaltens von

anorganischen Kernformstoffen für die Herstellung von

Kernen für die Fertigung komplexer Seriengussteile

Dr.-Ing. A. Schrey*, Foseco Europe Marketing &

Technology, Borken/Germany; Dr. V. Haanappel,

Foseco Nederland BV, Enschede/Netherlands

5


Contents/Inhalt

14:45 Minimizing Air Entrainment in High Pressure Die Casting

Shot Sleeves

Minimierung von Lufteinschlüssen in Druckguss-

Kavitäten

R. Pirovano*, S. Mascetti, XC Engineering Srl, Cantù/

Italy; Dr. M. Barkhudarov, Flow Science Inc., Santa

Fe/USA

15:15 Innovative coating to prevent white film defects

Vermeidung des Gussfehlers „Weißer Belag“ durch

Penetrationsschlichten

C. Joachim*, C. Fourberg, Hüttenes-Albertus Chemische

Werke GmbH, Düsseldorf/Germany; M. Vorrath, Dr. K.

Seeger, Hüttenes-Albertus Chemische Werke GmbH,

Hannover/Germany

15:45 Equipment Availability and Energy Efficiency

– a Contradiction?

Verfügbarkeit und Energieeffizienz im Widerspruch?

Dr. P. Reichen*, U. Jordi, Bühler AG, Uzwil/Switzerland;

F. Hoffmann, Bühler GmbH, Mannheim/Germany

16:15 Performance of Long Thin Printed Sand Cores in

Aluminium Castings

Verhalten 3D-gedruckter, langer und dünnwandiger

Sandkerne im Aluminiumguss

T. Mueller, Voxeljet of America Inc., Canton/USA

6


Contents/Inhalt

16:45 Advancements in Die Lubricant Technology for the

Evolving Die Cast Process

Trennstoffentwicklungen für gestiegene Anforderungen

im Druckgießverfahren

D. Tomazic*, Chem-Trend (Deutschland) GmbH,

Gernlinden/Germany; J. Belyk, Chem-Trend L-P.,

Howell/USA

17:15 Development of Intelligent Green Sand Preparation

System

Entwicklung eines intelligenten Grünsand Vorbereitungs-

system

T. Sakai*, S. Katsuhito, O. Yuichi, SINTOKOGIO Ltd.,

Toyokawa/Japan

7

NEWCAST-Forum Mittwoch/Wednesday, 17.06.2015


NEWCAST-Forum 54

10:30 Competiveness by Leadership – Ensure the

Competitiveness of Foundries in High Wage Countries

by Using a Clear Leadership Model

Wettbewerbsfähigkeit durch Leadership - Mit richtiger

Führung die Wettbewerbsfähigkeit der Gießereien in

Deutschland sicherstellen

H. Doppler, Managementberatung Doppler, Freiberg am

Neckar/Germany

11:00 TENSAL® - Development of a High Strength Aluminum

Casting Alloy for the Production of Highly Loaded

Chassis Components

TENSAL® - Die Entwicklung eines Aluminium-

Gusswerkstoffs mit erhöhter Festigkeit für die Fertigung

hochbelasteter Fahrwerkskomponenten

Dr. rer. nat. K. Greven*, M. Loganathan, O. Grimm, KSM

Castings Group GmbH, Hildesheim/Germany

11:30 Productivity and Ecology Considerations of High

Production CB Processes

Produktivität und Ökologie in der anspruchsvollen Cold-

Box-Serienfertigung

J. Archibald*, M. Hartman, J. Benavente, ASK-

Chemicals, Dublin Ohio /USA

8


Contents/Inhalt

12:00 Robust cast product design driven by front-loading

through virtual experimentation and optimization –

baseline technology for efficient CAE-Development

Processes

Robustes Gussdesign durch virtuelles Experimentieren

mit Gießprozess-Simulation als Baustein innovativer

Entwicklungsprozesse

Dr.-Ing. H. Bramann*, Dr.-Ing. J. C. Sturm, H.

Rockmann, H. J. Gaspers, MAGMA Gießereitechnologie

GmbH, Aachen/Germany

12:30 International Foundry Challenge - Suitable Production of

Thin Walled Aluminum Prototype and Small Series

Castings for Body in White Applications

Herausforderung Guss - Anforderungsgerechte

Fertigung dünnwandiger Aluminium Prototypen und

Kleinserien im Karosseriebau

Dr. J. Gundlach*, Dr. J. Detering, Grunewald GmbH &

Co. KG, Bocholt/Germany

13:00 Methodical, Automatic Optimization of the Casting

Process in Terms of Economy, Resource Efficiency and

Quality

Methodische, automatische Gießprozessoptimierung auf

Wirtschaftlichkeit, Ressourceneffizienz und Qualität

P. Kohlmeyer, G. A. Röders GmbH & Co. KG,

Soltau/Germany

9


Contents/Inhalt

13:30 Development of a Novel AlCu-Cast Alloy for Thermally

High Loaded Cylinder Heads

Eine neue AlCu-Gusslegierung für thermisch

hochbelastete Zylinderköpfe

Dr.-Ing. F. J. Feikus*, Dr. L. Kniewallner, Nemak Europe

GmbH, Frankfurt/Germany; M. Rafetzeder, Dr. M.

Djurdjevic, B. Stauder, Nemak Linz GmbH, Linz/Austria

14:00 Lightweighting the Right Material at the Right Place - A

Comparison of Iron, Aluminum, Magnesium and Carbon

Fiber

Leichtbau: Das richtige Material am richtigen Platz: Ein

Vergleich zwischen Eisen, Aluminium, Magnesium und

Karbon

K. Decking*, M. Holtkötter, Georg Fischer Automotive

AG, Schaffhausen/Switzerland

14:30 Energy Balance and CO2 Emissions Study for the Total

Life Cycle of Engine Blocks from Aluminum and Cast

Iron

Studie zur Energiebilanz und CO2-Emisionen von

Zylinderkurbelgehäusen aus Aluminium und Gusseisen

Dr.-Ing. A. Sobota*, W. Görtz, Eisenwerk Brühl GmbH,

Brühl/Germany

10

WFO Technical Forum Donnerstag/Thursday, 18.06.2015


WFO Technical Forum 76

11:00 Keynote

The foundry of the future-advanced managing and

manufacturing concepts for a global competitive cast

iron plant

J. Fesch, Sakthi Portugal Group SA

11:45 Comparing the USA and Europe Casting Industries

D. Trinowski, Hüttenes-Albertus Chemische Werke

GmbH

12:15 RFI in No Bake Foundries

C. Wilding, Omega Foundry Machinery Ltd.

Peterborough/UK

12:55 Up-date on use of blended Bentonite & Leonardite

B. Officer, P. Verdot, Amcol Metalcasting

13:20 Environmental Inorganic binder systems

A. Tagg, John Winter, Geopola

13:45 Innovative approach to training - A challenge for our

industry

Dr. P. Murrell FICME, Cast Metals Federation

Birmingham/ UK

11


Contents/Inhalt

14:10 Novel No bake binders with reduced fume

S. Trikha, Huttenes Albertus

14:35 Rapid development of new castings using simulation

techniques

T. Roy, Texmaco Rail. Kolkata/ India

15:00 Improving Casting Quality and Productivity Through the

Application of a High Efficiency, Engineered Lustrous

Carbon Former

N. Richardson S & B/ UK

12

Technical Forum in Kooperation mit dem VDIFreitag/Friday, 19.06.2015


VDI Technical Forum 87

10:30 Proven Odor and VOC Abatement in Foundries

Bewährte Geruchs- und VOC-Abreinigung in Gießereien

C. Mülleder*, M. Klimisch, Dr. M. Krenn, CTP Chemisch

Thermische Prozesstechnik GmbH, Graz/Austria

11:00 Determination and Assessment of Volume Defects in

Aluminum Castings by Means of Computed Tomography

Bestimmung und Bewertung von Volumendefiziten in Al-

Gussstücken mittels Computertomographie

Dr. B. Oberdorfer*, D. Habe, Dr. E. Kaschnitz, G.

Schindelbacher, Österreichisches Gießerei-Institut

(ÖGI), Leoben/Austria

11:30 Simulation-Aided Optimization of Gating and Feeding

Systems for Aluminum Sand Castings

Simulationsgestützte Optimierung der Gießtechnik für

Aluminium Sandguss

Dr.-Ing. G. W. Dieckhues*, H. Rockmann, Ohm & Häner

Metallwerk GmbH & Co. KG, Olpe/Germany

13


Contents/Inhalt

12:00 Simulation in the Support of the Development of

Innovative Processes in the Casting Industry

Simulation zur Unterstützung der Entwicklung

innovativer Prozesse der Gießereitechnik

Dr.-Ing. M. Todte*, Flow Science Deutschland GmbH,

Rottenburg/Germany; Dr. A Fent, H. Lang, BMW AG,

Landshut/Germany

12:30 Economic and Energy-Related Aspects of Batch

Planning and the Optimization of Melt Operations

Chargenplanung und Optimierung des Schmelzbetriebs

unter betriebswirtschaftlichen und energetischen

Aspekten

K. Bembenek*, Dr. H. Ortloff, K. Herzog, S. Recktor,

RGU GmbH, Dortmund/Germany

13:15 High Effective Linked Cylinder Head and Cylinder Block

Production in Double Casting at Volkswagen

Hocheffektive verkettete Zylinderkopf- und

Zylinderkurbelgehäusefertigung im Doppelkokillen-

Kippguss bei Volkswagen

Dr.-Ing. F. Hansen*, Dr.-Ing. R. Rösch, S. Uhde, K.

Wagner, Volkswagen AG, Leichtmetallgießerei

Hannover, Hannover/Germany

14


Contents/Inhalt

13:45 Graded Sands: Impact of Grain Size Distribution on

Molding Materials

Konfektionierte Sande: Einfluss der Kornverteilung auf

Formstoffparameter

Dr. H. Görke*, Dr. J. U. Zilles, M. Demary, Quarzwerke

GmbH, Frechen/Germany

14:15 Increase Your Casting Output, with 30% Higher

Productivity on DISA Vertical Machines

Steigern Sie Ihr Ausbringen mit 30% höherer

Produktivität auf vertikalen DISA-Formanlagen

B. W. Haugbølle, DISA Industries A/S,

Taastrup/Denmark

14:45 A Novel Emission Control System for the Reduction Air

Pollutants in Flue Gases from Foundries

Abgasreinigungssystem zum Abbau von

Luftschadstoffen in Abgasen von Gießereien

Prof. Dr. P. Wiesen*, Bergische Universität Wuppertal,

Wuppertal/Germany; Prof. M. S. Johnson, University of

Copenhagen/Denmark; F. Hartung, M. Gallus, Infuser

Deutschland GmbH, Mannheim/Germany

15


Contents/Inhalt

15:15 Influence of Silicon Content, Strain Rate and

Temperature on Toughness of High Si Ferritic Ductile

Cast Iron

Einfluss von Siliciumgehalt, Dehnrate und Temperatur

auf die Zähigkeit von ferritischem Gusseisen mit

Kugelgraphit mit hohem Siliciumgehalt

T. Ikeda*, Dr. Eng. U. Takuo, Dr. Eng. O. Keisaku, K.

Nobuhiro, HINODE Ltd., Tokio/Japan

15:45 Automated Quality Control for Tools, Patterns and Cast

Metal Parts with Optical 3D Metrology Systems

Automatisierte Qualitätssicherung von Werkzeugen,

Modellen und Gussteilen durch optische 3D-

Messsysteme

S. Adolf, GOM Gesellschaft für Optische

Messtechnik mbH, Braunschweig/Germany

16:15 Defective Castings Detection in Large Ductile Iron

Production Using a Machine Learning Approach

Ausschussdetektion bei Großguss aus Gusseisen mit

Kugelgraphit mit selbstlernenden Algorithmen

Dr.-Ing. G. Bertuzzi, SACMI Imola S.C., Imola/Italy

16


Contents/Inhalt

16:45 Thread New Paths in Automated Defect Recognition

(ADR) for Castings. Faster – More Accurate – Reduced

Setup Time – Less Costs

Neue Wege in der automatischen Fehlererkennung an

Gußteilen. Schneller - Genauer - Kaum Rüstzeit -

Geringere Kosten

H. Schulenburg, VisiConsult GmbH, Stockelsdorf/

Germany

17:15 Best Paper Award

Sponsored by Hüttenes-Albertus

18


Energy Efficient Use of Medium Frequency Induction Furnaces with

Constant Power Range of Power Optimized Charging

Energieeffizienz in der Gießerei am Beispiel der leistungsoptimierten

Chargierung von Induktionstiegelöfen

Dr. M. Rische*, Dr. E. Dötsch und R. Ibach, ABP Induction Systems

GmbH, Dortmund/Germany

Suitable charging raises the energy efficiency

The batch type mode is the most economical procedure to operate modern medium-

frequency melting furnaces. By this way, the finally prepared melt is tapped completely and

the furnace is started up again with solid melting stock. From the plant technical viewpoint,

such a batch mode is enabled in that the current, voltage and frequency in the resonant

circuit of the converter power supply are automatically adapted to the varying electrical load

of the stock being melted in the induction coil. The aim is to adjust these values in such a

way that nominal power is supplied to the MF furnace over the entire melting period, thus

achieving the shortest melt time with the lowest energy requirement.

Three factors are decisive in achieving this aim:

- Power is supplied by a constant power converter,

- The melting stock has an adequate bulk density,

- Feed materials are charged in a suitable manner.

The lecture discusses these three criteria in detail. The design of the frequency converter for

supplying constant power is first described. The influence of bulk density and lastly the

charging process are then outlined on the basis of operating data determined in practice.

19


The constant power converter is designed to the state-of-the-art, so that when operating the

furnace, nominal power (as a product of current and voltage) not only adjusts itself to a

defined point, but also to a curve between 70% and 100% of these two values. When

charging starts, the power input is initially at the nominal value due to a high current flow -

even at a lower voltage and frequency – because of the high magnetic conductivity of the

cold ferrite melting stock. Once the Curie temperature has been reached, the melting stock

then becomes more or less high-ohmic, so that the converter runs at the voltage limit and

thus strives to induct sufficient current to retain nominal power. In the further course of

melting as the ratio of melted stock in the furnace rises, the current, voltage and frequency

approach their nominal values whilst the nominal power continues to remain constant.

Apart from deploying such a constant power converter to ensure an adequate coupling of the

electro-magnetic field in the early stages of the melting period, a high bulk density of the

melting stock is also required for inputting nominal power. This is the case in a 12-t, 8400kW,

250Hz crucible furnace fed with a mix of small pieces of returns, dry chips and scrap steel

shavings. With the resulting optimum operating procedure, an appropriate tandem system

continuously turns out 14 t/h of melt with high carbon content for producing brake disks at

great economic efficiency.

The current and voltage swing of the constant power converter described is limited for

technical and economic reasons, thus if the melting stock has a too low bulk density, this can

often no longer be compensated. The power then drops in the first 10 to 15 minutes of the

melting period after the Curie temperature has been exceeded, whereby such a fall can

sometimes be up to 70% of nominal power. This can be avoided by a suitable sequence for

charging the ferro-

magnetic feed materials. To this end, the furnace is just partly filled at the start, so that there

is a sufficient volume in the crucible to subsequently charge ferro-magnetic material in small

portions in accordance with the stipulations made by the melt processor and to thus make

use of the positive influence of magnetic conductivity. Using

examples taken from practice, it is demonstrated that the

melting plant can be operated in the optimum manner by

suitable charging – even if the feed materials have a low

bulk density - at high energy efficiency.

20


A New Generation of Ceramic Foam Filters Providing Real

Opportunities for Cleaner Steel Castings

Die nächste Generation Stahlfilter für noch besseren Guss

N. Child, Foseco International Limited, Tamworth/United Kingdom

Background

Many steel castings are sophisticated, high technology components, and are often an

important part of complex, assemblies and systems for a huge range of applications. The

castings are used in many industries, some examples are

Railway - for safety critical components including brake and engine parts

Energy - for high integrity heavy duty safety critical castings including high pressure

pumps, valves and nuclear reactor parts

Military - for high specification castings to be used as structural parts for military

platforms and safety critical components in military aircraft

The complexity and integrity of steel castings that are produced is rapidly increasing and the

market demand is not expected to decline. An example is the use of stainless steel castings

in the high end automotive industry for turbo charger housings and exhaust manifolds that

can operate at ever increasing temperatures on high efficiency engines

The use of ceramic foam filters was first used in the steel casting industry towards the late

1980’s and the technology associated with steel filtration systems and application has

continually improved. Now ceramic foam filters are applied in tiny components where the

smallest of inclusions will result in the scrapping of the casting, through to castings weighing

in excess of 40 Tonnes.

21


The filters perform two major functions that generate a wide number of benefits for the

casting producer.

Filtration - Removing the majority of non-metallic inclusions in the metal stream at the

filter face; smaller particles are then trapped by a variety of chemical and physical

mechanisms within the filter structure. Various investigations show that filters are in

the region of 80% efficient at removing inclusions

Flow Control - Reducing the energy within the metal stream and facilitating low

turbulence as the casting cavity fills

The benefits of filtration of steel castings are well documented and include higher integrity,

less scrap, reduced rectification time and costs, improved surface finish, reduced inspection

requirement, “right first time”

The Modern Casting “48th Census of World Casting Production” shows that the global

production of steel castings is 11 million tonnes. Market surveys estimate that less than 8%

of the global steel casting tonnage is filtered, this relates to over 10 million tonnes of castings

not being filtered.

Foseco undertook a market study to understand why the uptake of steel filtration technology

has not been more rapid and reached a higher level. There are many reasons that can be

cited including casting size (some castings are currently too big to filter), casting type (some

castings can be very low integrity), Geography (low labour costs making high levels of repair

cost effective). It became apparent that many foundries do use filtration technology but only

apply the filters to a limited proportion of the castings they produce; the reason for this

includes concern that the application of the filter will cause problems and inconsistencies

during the casting process particularly in terms of mould fill. It was also noted that there is a

clear casting producer demand for higher efficiency filters.

22


The Development of the optimised steel filter

There was a clear market need for a steel casting filtration system that provided more

consistent performance in demanding applications together with a desire for enhanced

filtration efficiency.

The new filter is based on improved zirconia ceramic technology and incorporates a ceramic

frame around the sides or the filter. This combination allows the filters to be lower in weight

while maintaining the required strength to withstand the impact and passage of molten steel.

The lower weight reduces the occurrence of pore blockage within the filter structure, and

facilitates the ability to supply a product with finer porosity that performs consistently. In

addition the frame and robustness of the ceramic provide a filter that exhibits superior

friability characteristics and therefore reduces the potential incidence of filter related defects

in the casting.

The new filter is available in two porosities, 10 pore (coarse porosity) and 15 pore (fine

porosity). The intention is that 10 pore will provide a filter that consistently primes and

provides reproducible performance in terms of metal flow rate and capacity before filter

blockage. 15 pore will provide enhanced filtration efficiency where required and will be

particularly well suited to high specification, high integrity, high alloy casting applications.

The paper will highlight the laboratory tests that were used to characterise the performance

of the filters and the benefits of application to steel castings in the foundry.

23


New Trends in Feeder Technology

Neue Trends in der Speisertechnologie

G. Brieger, Chemex GmbH, Delligsen/Germany

1.) Introduction Chemex GmbH (Member of the HA-Group)

2.) Features and advantages of CB-bonded Sleeves

-fluorine free => no surface defects related to fluorine

-trouble-free storage

-high pressure resistance

-low tolerences

24


3.) Introduction Tele Feeder

-both parts exothermic

-no pressure on the lower part

-better molding sand compaction below the feeder

-well defined breaking edge => reduce fettlling costs

‐ special tele feeder for Aluminium-sand-casting

4.) Introduction side feeder for DISA molding plant

‐ allows the production of some castings on a DISA molding plant

25


5.) CB bonded Exothermic Contour Breaker Core System

‐ reduce the nessesary number of feeder

‐ saves time and reduce cutting and fettling costs

‐ reduce the feeder volume

26


High Value Added Cast Parts - Advanced Feeding Systems and

Metallurgical Improvements

Gussteile mit hoher Wertschöpfung – Verbesserte Speisungstechnik

sowie metallurgische Verbesserungen

J. Prat, ASK Chemicals España, Castro Urdiales/Spain; G. Artola, J.

Izaga, IK4-Azterlan, Metallurgical Technical Centre, Durango/Spain

The attention that foundry companies give to simulation tools and the permanent

improvement of their response doesn’t only ease adapting the results for the demands of the

customers, but also evidences diverse interactions of metallurgical nature. The achieved

improvements are especially obvious in the case of high priced alloys (Hastelloy, Inconel,

Superaustenitic, etc.) and for parts that are submitted to exhaustive radiographic inspections.

The cast steel parts, in their different material typologies, offer immense improvement

opportunities. Among these, this work is mainly oriented towards the yield optimization and

the metallurgical improvements. Regarding the net/gross weight ratio, new feeding

technologies have been developed, allowing yields beyond 75%.

Even though the foundry industry, as a whole, has incorporated relevant technological

advances into their productive processes, the specific field of feeding system design criteria

hasn’t improved in the same proportion. The application of powerful calculation and

simulation tools doesn’t always come together with the optimization of key indicators. The

part reworking costs stay close to invariant, the yield values hardly reach 50% and the

metallurgy of the processed alloys is kept under nearly unchangeable principles.

27


The work that is presented here is a clear example of cooperation between companies

belonging to the same sector, since it has been developed by a special alloy foundry, a

company belonging to the auxiliary sector and a Research Institute. The starting point is a

deep review of

the feeding systems that are employed for the manufacture of cast steel components, to lead

in the end, to the identification and evaluation of the metallurgical advantages that can be

exploited in the most thermally affected zones.

Metallurgical comparisons are established between significant areas of the parts, among

which, both the zones affected by the feeding system and the zones far from it are relevant.

Based on metallurgical considerations, the thermal effects of the feeding systems are

evaluated.

A complex variable matrix has been defined and studied, taking into consideration high

value-added materials, their metallurgy both in liquid and solid state, novel feeding devices

such as core-risers, riser-paddings and EXACTCASTTM (patented) mini-risers, and advanced

calculation concepts.

The industrial scale validation stage has been performed, jointly, in the facilities of ASK

Chemicals, IK4-Azterlan and several steel foundries, focusing the development efforts

towards the yield optimization and the evaluation of the metallurgical improvements, that are

associated with the rationalization of the local thermal solidifications.

The most important achieved results are explored, new designs and formulations for the

feeding devices are proposed and the latest news is presented in terms of the metallurgical

advantages offered by the developed technology.

Keywords: Mini-risers, feeding systems, net/gross yield, feeding distance, thermal

modulus and feeding volume demands.

28


Inorganic core sand: Decoring of castings and sand reclamation

Anorganisch gebundener Kernsand: Entsanden von Gussteilen und

Regeneration des Kernsandes

Dr.-Ing. U. Dinglreiter, R. Scheuchl GmbH, Ortenburg/Germany

Abstract

Inorganic binding systems for sand cores are on the rise in light metal foundry operations. A

successful implementation of inorganic bonded cores requires the adaption of all processes

of casting generation. Scheuchl developed an effective decoring process of castings with

inorganic bonded sand cores. Also, a complete new process of sand reclamation for

inorganic sand was designed and implemented in several automobile foundries in Europe

and Asia.

1. Inorganic binding systems on the rise

Inorganic binding systems for sand cores are used successfully in light metal foundries. At

present Daimler Benz applies an inorganic binding system of Huettenes-Albertus (HA).

Volkswagen produces in 2015 roughly 3 million of castings with inorganic bonded core sand

with binders from HA in Hannover and ASK in Poznan. BMW has changed as a first its light

metal foundry completely to the use of inorganic binding systems of ASK, some years ago.

For the new generation of castings BMW focuses consequently on advantages of the

inorganic binder system Inotec. Considerable increases in productivity and cost savings are

realized, for example by means of using central feeders in crankcases, for which the

inorganic binding system is a prerequisite. The implementation of inorganic binding systems

requires an adaption of all processes along the value stream including the decoring and the

reclamation of used sands. In cooperation with the automobile foundries Scheuchl developed

and put into serial operation an effective process for the decoring and for the reclamation of

the used core sands with inorganic binding systems.

29


2. Decoring of castings with inorganic bonded core sand

In general, there are four main failure issues when decoring

castings with inorganic binders (picture 1):

Adhesions

Blockings

Penetrations

Dust formation

Picture 1: Four main failure issues at the decoring process

In order to prevent these failure issues, a four-stage standard decoring process for castings

with inorganic bonded core sand was developed and introduced successfully for a multiplicity

of castings:

Pre-decoring with optimised number and hitting position of pneumatic hammers

Vibration decoring with optimised oscillation amplitude and frequency

Intermediate decoring (hitting the castings between two oscillation cycles)

Post-decoring with specially developed RS-frequency transducers

The first three steps of the decoring process were consequently derived from existing

methods and optimised towards the requirements of inorganic bonded sands. The post-

decoring process was developed in particular to avoid adhesions and to improve the removal

of adhering sand residuals due to penetrations.

Thereby the casting is stimulated to self-oscillation

without fixation by a RS-frequency transducer. This

four step decoring process has been established as a

standard decoring process in most foundries with

inorganics.

Picture 2: Decoring station with automatic robot loading for different castings

30


3. Reclamation of inorganic bonded core sands

In order to close the cycle of materials when using inorganic core binders, it is necessary to

reclaim the core sands after the cast and to re-use them. Conventional reclamation

processes for organic binders are not sufficient. Together with foundry operators and core

binder manufacturers Scheuchl has developed an effective and economical method of

reclamation of inorganic bonded core sands. For the development of the Scheuchl process

firstly the individual process steps were identified, then the ideal sequence of the multi-level

process was determined and after that the single process parameters were optimized.

Binding systems of most binder suppliers were tested extensively in a pilot plant and Cycle

tests were carried out. After the testing procedures an energy saving process was designed.

The BMW light metal foundry reclaims inorganic bonded core sands for cylinder heads, crank

cases and chassis components. Also the light metal foundry of the Volkswagen group

reclaims inorganic bonded core sand with a Scheuchl modular reclamation system. Recently,

the Scheuchl reclamation process was successfully installed and taken into operation in the

new light metal foundry of BMW / Brilliance in Shenyang, China.

Picture 3: Modular unit for reclamation of inorganic core sands

31


New Possibilities of Surface Finishing for the Die Casting Industry

Neue Möglichkeiten der Oberflächenbearbeitung für die Druckgussindustrie I. Löken, Spaleck Oberflächentechnik GmbH & Co. KG, Bocholt/Germany

Background

The key components in the die casting process are the die casting machine, the metal alloy

and the tool, forming the shape of the die casting part. These tools are made of steel and

there is a tremendous effort to achieve long life times of these dies. Despite the effort, there

is always a certain wear of the metal dies, which will result in a burr respectively in sharp

edges at the final die casting parts. To eliminate these burrs and smoothing the edge of the

components, slide grinding processes are used in many die casting companies all over the

world.

State of the art

A very common way to deburr die casting parts is to treat them in a classical roundtub

vibrator, as shown in picture 1.

A roundtub vibrator is an easy and flexible machine to treat parts

in a batch process. Due to the nature of the design of the

roundtub vibrator, there are also limitations of the system. The

batch process is not suitable to interlink the roundtub vibrator

with an existing die casting machine, which is more or less

generating a continuous flow of parts.

A typical treatment time for die casting parts is about 15 minutes. At the end of a treatment

cycle in a roundtub vibrator there is a separation step, which takes normally in a medium

sized roundtub vibrator up to 5 minutes. This results in a total process time of 20 minutes,

where we can easily calculate, that 25 % of the treatment cycle is used for the non-value

adding step called “separation”.

Picture 1

32


The biggest disadvantage of a roundtub vibrator is the damage of parts, which will be treated

and separated by a flap. For mass articles it is accepted, but not desirable to have these

small damages. But due to the increased quality expectations of the die casting customers,

more and more parts will be specified with no damages allowed. This is a challenge the

roundtub vibrator just cannot achieve or can achieve the significant reduction in the capacity

and output of the machine.

Spaleck Solution

To address the main disadvantages of the roundtub vibrator, which are separation time and

damages of parts, continuous vibration machines have been implemented into the market

place a long time ago. The existing continuous vibration machines on the market have also

two main limitations, which are large floor space required for a linear continuous vibration

machine and / or not perfect movement of media and parts with regards to spiral continuous

vibration machines.

Spaleck has developed a continuous vibration

machine in a screw design, which is called

DL1000. This machine is constantly feeding

the parts and media from the bottom via an 18

meter long treatment channel up to the top of

the machine. This design allows us to have the

perfect combination of a long treatment

channel, resulting in an effective deburring of

parts connected with an optimum usage of

floor space, which reduces production costs.

With all these advantages we will not

compromise the treatment movement of parts

and media in the machine.

Picture 2

33


The perfect movement of parts and media in the machine allows us to generate a gentle

treatment of parts without any damages during the way through the machine. But the

continuous movement also allows us to treat parts individually to avoid any damages of parts

from each other.

Picture 3 is showing a typical

production cell of a larger system,

which is called DL2000, where parts will

be loaded by hand and the treatment

takes place in the continuous vibration

machine. Afterwards the parts will be

separated from the media during

screening machines and all of this is

connected with a linear hot air dryer.

34


Methods for Describing the Flow Behavior of Inorganic Core Sand

Material for the Production of Complex Cast Components

Methoden zur Beschreibung des Fließverhaltens von anorganischen

Kern-formstoffen für die Herstellung von Kernen für die Fertigung

komplexer Seriengussteile

Dr.-Ing. A. Schrey*, Foseco Europe Marketing & Technology,

Borken/Germany; Dr. V. Haanappel, Foseco Nederland BV,

Enschede/Netherlands

The use of inorganic bonded cores for the production of automotive castings in the gravity or

low pressure die-casting process was established in the recent years in several light metal

foundries.

There are high demands on the flowability of the core sand material during the compaction

process in order to achieve a consistent production of thin-walled sand cores.

High sand compaction is a key feature to produce castings with smooth casting surface finish

in the gravity or low pressure die-casting process without the application of any sand coating.

Due to the increasing complexity of the components to be produced, the requirements for the

flow behavior increase continuously. Hence the developers of inorganic binders are

constantly asked to improve the flow characteristics and the subsequent compaction of the

core sand material.

Thin cavities in core boxes are difficult to fill as the existing air has to be removed during the

compaction process and the subsequent sand compaction has to be as high as possible.

In the present work different methodological approaches are presented for both a

quantitative and qualitative description of the sand flow which will support the development of

binders with improved flow characteristics.

35


The methods in use vary from conventional test core boxes to measure the degree of

compaction, and the adaptation of methods from powder and bulk solids technology and

eventually the use of simulation methods for computer-aided prediction of the flow

characteristics of inorganic-bonded sand.

In particular, the computer-aided simulation of the particle flow is described in detail in this

paper, since it will play an important role for the future management of the increasingly

demanding tasks in context to the processing of core sand material.

Special physical parameters of the sand mixture and their impact on the computer-aided

description of sand flow will be discussed in detail and mirrored in practical experiments. The

correlation between results of the simulation with those of classical physical measurement

processes will be evaluated.

Inorganic core sand binders and additives, which have been optimised by means of the

above methods, meet all requirements for the production of complex cores, in particular for

the manufacture of water jackets for cylinder heads.

36


Minimizing Air Entrainment in High Pressure Die Casting Shot Sleeves Using flow analysis software to optimize piston velocity

Minimierung von Lufteinschlüssen in Druckguss-Kavitäten

R. Pirovano*, S. Mascetti, XC Engineering Srl, Cantù/Italy;

Dr. M. Barkhudarov, Flow Science Inc., Santa Fe/USA;

Abstract

A particular challenge in High Pressure Die Casting is to achieve optimal conditions in the

shot sleeve from which metal is injected into the die cavity. The speed of the plunger in a

horizontal shot sleeve must be carefully controlled to avoid unnecessary entrainment of air in

the metal and, at the same time, minimize heat losses in the sleeve.

The present work presents a general analytical solution for the flow of metal in a shot sleeve,

under some reasonable assumptions. Results are validated with three-dimensional numerical

modeling of the process. Coupled with parametric optimization, the numerical model shows

similar best process conditions to those predicted by the analytical model in a fully 3D,

viscous and turbulent environment.

1. Analytical model

Using shallow water approximation for the interaction of the moving plunger and liquid metal,

considering a shot sleeve of a rectangular cross-section and omitting viscous forces, it is

possible to derive a general solution for the plunger speed as a function of time and of the

maximum admitted surface slope. This allows the engineers to precisely control the behavior

of metal in the shot sleeve during the slow-shot stage of the high pressure die casting

process: by defining any maximum permitted wave slope it’s possible to keep a sufficient

safety margin to minimize the risk of air entrainment.

37


2. 3D numerical simulations and optimization

Three-dimensional simulations were used to validate some of the predictions of the simplified

model. The simulations include all the important physics of the die casting process, such as

the more realistic condition of viscous flow and a circular channel cross-section. Moreover,

several additional outputs are available to take in account many characteristics of the

physical phenomenon.

Several aspects of the numerical solution match the analytical solution quite well, with few

differences due to the more accurate representation of the reality of the 3D simulations.

Furthermore, coupling the CFD software with a parametric optimization it is possible not only

to obtain a plunger speed curve that should be safe respect the risk of air entrainment, but

also to get the best one that optimize more than one objective. In the present study optimal

solutions that at the same time minimize both the amount of air entrained and the time of the

slow shot stage have been researched.

Picture 1: Time lapse sequence of shot sleeve filling, showing wave formation.

Colors represent velocities, from blue (slow speed) to red (high speed).

[1] M. Barkudarov, Minimizing air entrainment in a shot sleeve during slow-shot stage, Die

casting engineer, May 2009

[2] S. Mascetti, Using flow analysis software to optimize piston velocity for an HPDC

process, Die casting engineer, September 2010

38


Innovative Coating to Prevent White Film Defects

Vermeidung des Gussfehlers “Weißer Belag” durch

Penetrationsschlichten

C. Joachim*, C. Fourberg, Hüttenes-Albertus Chemische Werke GmbH,

Düsseldorf/Germany; M. Vorrath, Dr. K. Seeger, Hüttenes-Albertus

Chemische Werke GmbH, Hannover/Germany

Foundries are increasingly faced with a rising demand on the quality of castings, the

dimensional consistency, and importantly the surface quality. For many years foundrymen

have been struggling with the casting defect “white film”, which appears on the casting

surfaces of thick-walled castings made of nodular graphite cast iron.

This is a pockmark-like, rough area on the casting surface, which is covered with a white film.

The film is removed by sandblasting the castings; however the irregular surface remains and

often leads to graphite degeneration. The only corrective measures described in literature [1]

are as follows:

Lower the pouring temperature

Increase the addition of new sand

Examine the loss on ignition, electrical conductivity, nitrogen content and if necessary

the phosphorous content of the reclaimed material

Increase gas permeability

Reduce the amount of curing agent for furan resin bonded moulds

Minimise the oxygen-affine elements, examine the melt additives

etc.

39


Unfortunately the above measures are either insufficient or cannot be fully implemented by

the customer. For this reason, this casting defect leads to higher fettling costs e.g. due to

rework, additional wall thickness, and in some cases higher appraisal costs.

The Hüttenes-Albertus team has investigated in great detail the cause of this problem.

Working in close collaboration with selected partners from the foundry industry, a group of

R&D chemists and product managers carried out several field trials to find out which causes

are responsible for this defects in the process.

An innovative impregnating coating was developed by closely analysing the causes for the

emergence of the film and carrying out individual process steps to overcome the defect. This

coating is applied to the affected areas within an existing process (binder system / reclaim /

material) by means of brushing. This leads to a complete suppression of the white film.

Fig. 1

(left side: treated with the impregnation coating; right side: traditional production)

Literature

[1] 2. Edition: Guß- und Gefügefehler – Stephan Hasse: Berlin - Schiele & Schön, 2003

40


Equipment Availability and Energy Efficiency – a Contradiction?

Verfügbarkeit und Energieeffizienz im Widerspruch?

Dr. P. Reichen*, U. Jordi, Bühler AG, Uzwil/Switzerland; F. Hoffmann, Bühler GmbH, Mannheim/Germany

Abstract

The increasing prices of energy and raw material pose great challenges for the foundry

industry. The search for the ideal model for optimizing resources, implementing energy

savings and reducing costs at the same time is very complex, since a large number of

parameters come into play. A simplified calculation model indicates a significant potential to

reduce energy consumption by improving the overall equipment effectiveness (OEE) and

thus the availability of the die casting cell while reducing at the same time the manufacturing

costs.

Power consumption in production environment

The foundry industry established key indicators for energy efficiency to compare the energy

consumption and performance of die casting machines. The actual benchmark used in the

competition between foundries though is the total consumption of energy and, consequently,

the costs per produced part in the real manufacturing scenario. What actually counts for the

overall optimization of power consumption is therefore not only the reduction of the electrical

energy required for the machine, but also the power that is required for melting the metal or

providing additional resources such as compressed air or cooling water. Studies have also

shown that the conventional spraying process is responsible for a disproportionally high

quantity of the total energy consumption because of the amount of compressed air energy it

takes up.

41


Energy measurement report identifies potential

An energy measurement report contains data captured in an actual production environment

including their correlation to a specific manufactured part. Eletrical energy is quite easy to

measure, while metering the compressed air consumption and cooling water treatment

presents a challenge for the measuring set-up. The individually recorded values need to be

converted by

calculating conversion factors for compressed air and cooling water that are specific to the

foundry based on local conditions. On the basis of these results, it is possible to make

specific improvements to machine settings, to the spraying technology or to the cell concept

– thus reducing the energy usage and, consequently, the costs per manufactured part.

Downtime increases the energy consumption per good part

In addition to the observations mentioned above, casters need to look at the overall

equipment effectiveness (OEE) of their casting cells, since it directly affects the profitability of

the plant. In this context, downtime of cell components is of particular interest. In order to

show the difference between possible and actual production time, it has to be evaluated in

depth. Even if the machine is idling temporarily, the molten product must be kept warm and

all required subassemblies must remain in stand-by mode. Currently, up to 60% of the power

consumption during regular production accumulates even though the machine is not

producing. As a result, all good parts manufactured have to help bear the costs of “stand-by

losses”. In other words: higher overall equipment effectiveness reduces the energy

consumption per good part. It becomes obvious that improving the OEE has not only an

effect on optimizing the energy efficiency of the die casting cell, but also greatly impacts part

costs.

Model provides the basis for decision-making

Taking into account an hourly rate of the machine (covering all fixed costs) and the actual

energy costs, a simple cost calculation model shows how the total costs for a good part can

be reduced by increasing the availability of the system: a 15% improvement of the OEE

affects the manufacturing costs ten times more than simply reducing the energy consumption

by 15%. This approach provides an answer to the question of whether the goal of reducing

costs means an investment in new, low-energy system components or, alternatively, in

measures to increase the availability of an existing installation.

42


Conclusion: availability and energy efficiency pay off

The ever-increasing cost pressure and the politically driven necessity for energy savings

continuously calls for innovation, also in the die casting industry. The use of more energy

efficient die casting machines plays an important role in lowering the energy consumption.

The VDMA standard cycle for die casting machines has made them comparable.

Furthermore, a simplified model shows that the improvement of the overall equipment

effectiveness (OEE) also has a positive effect on the energy consumption per good part.

More important, an improved OEE has an even more significant impact on the balance sheet

for total costs per manufactured good part.

43


Performance of Long Thin Printed Cores in Aluminum Castings

Verhalten 3D-gedruckter, langer und dünnwandiger Sandkerne in

Aluminiumguss

T. J. Mueller, Voxeljet, Canton, MI

L. Andre, Solidiform, Fort Worth, TX

ABSTRACT

In the 15 years since printed sand molds and cores viable for a wide range of alloys have

been available, their value in product development and in low volume manufacturing has

been demonstrated many times over. While the use of printed cores with thicker sections has

proven viable and is in common use, little is known about the casting performance of long,

thin printed cores. It was uncertain whether they would be strong enough to withstand the

forces exerted by the flow of metal during filling. It was also uncertain whether they could

adequately vent gases generated during the casting process.

The authors undertook a systematic study to evaluate the limits of performance for printed

cores using cores covering a range of diameters

and lengths.

TEST DESIGN

For the test a series of thin-walled tubes (0.060” wall

thickness) were created with internal diameters

ranging from 0.25” to 0.875 inches and lengths

ranging from 2 inches to 12 inches.

Printed cores were used to form the internal

diameters and the cores were printed with an internal vent to allow gases generated during

casting to vent to the outside of the mold.

Figure 1. Test geometry for core evaluation including feeder bar and downtubes used in the test.

44


To ensure that conditions were consistent, all tubes of the same diameter were casted at the

same time, all fed from a common feeder at the bottom of the tube. Figure 1 shows the

tubes and feeder along with two downsprues. Two downsprues were used to increase the

feed rate to the tubes so they would fill before freezing off. The tapered area at the end of

each tube is a riser to feed the tube as metal shrinks during solidification.

This design allowed us to use a single core for

all six tubes of the same diameter. The core

resembled a harp with a core print

surrounding the cores and the cores running

parallel between them like strings on the harp.

Figure 2 shows a CAD model of the core. The

core contains a passage through the base to

allow the tubes to be fed from the bottom. The

core would be extremely difficult if not

impossible to create by conventional means.

Matchplates were created for each of the tube diameters. Vent lines connected the vents

from each of the cores to the outside of the mold. Each of the mold cavities were also vented

to the outside to allow complete filling of the mold.

Two copies of each of the six cores were created using an AFS57 chemically bonded silica

sand with 1.7% by weight furan based binder. A layer thickness of 0.3 mm was used.

Molds were chemically bonded sand using a phenolic urethane nobake binder. A layer of

carbon soot was applied to the cope and drag mold surfaces to aid in metal flow. The molds

were positioned so that they were vertically parted. The pouring cups were elevated to

increase the static pressure of the metal during pouring. A vacuum manifold was attached to

the mold where the vent lines emerged so that a low level vacuum (supplied by a shop

vacuum) could be used to assist in drawing out gases generated during filling. Aluminum

A356 was cast in the molds.

Figure 2. The core geometry used for the test contained six lengths of the same diameter core.

45


Twelve molds were cast, 2 for each of the 6 core diameters. Each tube was visually

inspected followed by x-ray and liquid penetrant inspection.

Figure 3 shows all twelve sets of tubes. Each smaller picture contains two sets of tubes, all

with the same inner diameter, and two tubes of each of the 6 lengths of core.

Figure 3. Seventy two castings were created, two for each of the test conditions.

RESULTS

The tubes were first evaluated for deflection during pouring. X-ray inspection showed

significant deflection in the longer lengths of the 0.250”ID tube, but not in the larger

diameters. The deformation of the small tube was great enough that, in longer lengths, part

of the tube did not fill, as shown in Figure 8. Non-fill due to core deformation is clearly visible

in the 8, 10, and 12 inch lengths of tube. No non-fill conditions were observed in any larger

diameter tubes.

Liquid penetrant inspection revealed a number of gas defects. The presence of the defects

raises two questions: What is the source of the gas?, and Why isn’t the core venting allowing

the gas to escape?

If the source of the gas is the binder in the core, it might be difficult to avoid such defects in

any casting.

46


There were a number of defects in the cast tubes but two definite trends were noticed:

Defects increased with increased pouring height

Smaller diameter tubes had fewer defects

If the binder was the source of the gas, we would expect similar defect levels in all castings.

However, the fact that defects were more frequent in castings made with greater pouring

height points to air entrained in the pour as the source of the gas. As the pouring height

increases, the velocity of flow increases and more air is entrained in the molten metal.

Consequently, more defects would be expected in those castings done with a greater

pouring height. This is consistent with the results obtained.

Determining whether the venting was adequate is more difficult. The diameter of the vent

passage increased with the diameter of the core. As the core diameter decreased, it became

more difficult to remove the unbound sand from the vent passage. For the smallest diameter

cores, it was impossible to remove the unbound sand. While gases could likely flow through

spaces between sand grains, the area available for flow would be drastically reduced.

The area of flow passage decreases as the core diameter decreases. We would expect to

see more defects in smaller diameter cores and the most defects in the smallest core where

there was nearly no venting available. Instead, we see the opposite situation. Apparently,

venting does not play a significant role in this situation.

CONCLUSIONS

1. Cores with diameters of 0.375 inches or more are rigid enough to resist significant

deformation during casting of aluminum when oriented in a vertical position. Cores

oriented horizontally would be subject to gravity and buoyancy forces that could result in

greater deflection

2. Gaseous emissions from a binder concentration of 1.7% is not a significant issue in

casting aluminum.

47


Advancements in Die Lubricant Technology for the Evolving Die

Cast Process

Trennstoffentwicklungen für gestiegene Anforderungen im Druckgieß-

verfahren

D. Tomazic, J. Belyk, ChemTrend (Deutschland) GmbH,

Maisach/Germany

Introduction

The Increasing demand for components manufactured with the High Pressure Die Cast

(HPDC) process requires both manufacturers and suppliers to improve their contribution to

the process to meet higher volume requirements while also striving to decrease the overall

environmental impact of the process. To achieve these goals, Chem-Trend initiated multiple

internal developments, while also participating in a project called “ProGRess”, to develop

new generations of release agents to help industry significantly increase productivity while

also decreasing environmental impact through improved application efficiency and reduced

resource consumption.

Release Agents and the High Pressure Die Casting Process: The HPDC process of non-

ferrous raw materials is consistently advancing technology to push the boundaries in what

type of components can be manufactured with this method. Process and alloy advancements

enable the industry to manufacture high-integrity, weight-optimized, near-shape components

in large scale. Yet, this ever-evolving advancement comes with challenges. The dies used

for this process are subject to high thermal and mechanical stress, which leads to reduced

die life with a negative effect on productivity and the overall environmental impact of a

foundry. In addition to this, the release agents that are essential for demolding parts also

have a significant influence on die life as well as part quality and productivity.

48


Today’s high performance release agents successfully achieve current requirements of the

modern HPDC process, yielding parts with high mechanical properties that requires

extended post-cast processes such as perfect parts cleaning and pickling, painting, e-coating

and joining via welding or adhesive bonding. Casters play an intricate role in supporting

product performance through appropriate release agent utilization procedures in terms of

both application location and quantity.

Advanced Release Agent Technology: The ability for a die lubricant to form a protective

film on the die, and the control of a multitude of die cast defects (e. g. drawings, warpage,

etc.), is dependent upon the surface temperature of the die. Thus, thermal balance is a key

factor in the production of high-quality die cast components. This comes into play with

today’s shorter cycle times for improved productivity. Additional energy is delivered into the

die every cycle from the molten alloy and often must be externally managed when die design

does not allow for adequate internal die cooling. Casters utilize release agents to overcome

shortfalls through high volumes of diluted material and sophisticated spray equipment.

Managing this can be a vicious cycle that leads to additional stress on die steel. Some die

lubricants are not capable of film formation at elevated temperatures. Thus, die temperatures

must be taken very low to build an effective film. This results in a significant Δ Temperature

and leads to additional die stress and shortened die life.

Figure 1: Example of wetting temperatures and cooling rates of different release agent

formulations

49


Development of materials that provide film formation at a broader temperature range (below

200°C and above 350°C) gives a caster additional freedom in the application of release

agents without endangering the quality of the HPDC parts. This is essential as some new

HPDC parts utilize alloys that require higher casting temperatures. Chem-Trend developed

specialized release agents for these processes that have the capability to wet and spread at

these elevated temperatures (Figure 1). Film formation at these higher temperatures also

reduces the thermal peak load at the die as faster heat removal from the die surface enables

the caster to maintain a die temperature respective to the quality requirements of the casted

HPDC parts without extending the cycle time of the process.

Chem-Trend’s second major project was completed in cooperation with several industry-

leading companies along with the University of Brunswick. This three-year project titled

“ProGRess” was promoted by the German Federal Ministry of Education and Research

(BMBF). The declared objective of this conjoint research project was to increase the

utilization efficiency of energy and resources by 15 percent within the complete process

chain of aluminum HPDC, including melting the basic material to the finished part. At the

same time, negative impacts on the productivity as well as the defined quality objectives had

to be met. In particular, „ProGRess“ pursued an improvement of the carbon footprint through

the reduction of CO2-emissions from industrial processes and the reduction of energy

consumption, which is in the segment of aluminum die casting especially high.

The new technology from this project is comprised not only of HERA™ release agent

technology but also includes a revised HPDC process with appropriate advanced application

technology. The use of this new approach requires a rethinking of the HPDC process as the

applied volumes of HERATM release agents are significantly lower than those of a

conventional process.

50


Considering the needed changes in the process chain, HERATM provides many benefits: the

tensile stress caused by high volumes of diluted release agent sprayed on a hot die is

reduced significantly and provides the user of this technology a proved increase in die life.

Further positive effects of this technique are an enhanced resource and energy efficiency, e.

g. reduced post processing of parts with high surface quality demands, shorter cycle times

due to less time for release agent application and blowing a die dry, no need for dilution

water, what saves resources, no effluent, lower need of compressed air, higher energy

efficiency what leads to a much lower environmental impact.

Proven Results: Both Chem-Trend’s advanced conventional and HERA™ release agent

technologies project significant increases in die life, cost savings and reduced environmental

impact for the HPDC industry. As well, both release agent technologies provide notable

improvements in comparison to the use of older conventional formulations.

Post-casting processes are benefiting from this new technology as well. First, fewer stress

cracks caused by thermal shocks in the die result in reduced rework levels. Second, all other

post-casting processing requirements such as cleaning, painting, e-painting and joining by

welding or adhesive bonding do not seem to be negatively influenced by the improved

conventional or HERATM technologies. Meanwhile, heat treatment (one of the most critical

post-casting processes) can be run with close to zero percent scrap rate as related to the

use of the new release agent technologies.

Conclusions

As the HPDC process evolves to manufacture increasingly complex componentry with

stringent economic and ecological goals, die casters and industry suppliers will also be

required to advance the capability of their products and processes to support the industry.

The development of novel release agents is one example of an industry partner meeting a

die casters need in combination with advancements in alloy, die design, thermal regulation

and release agent application technology. Most importantly, these advancements must be

done in consideration of the underlying factor of environmental protection and compliance

with the latest regulations. With industry partners, the development of technologies and

processes that improve die life and other measurable attributes will open the door to further

advanced applications in the HPDC industry.

51


Development of Intelligent Green Sand Preparation System Entwicklung eines intelligenten Grünsand-Vorbereitungssystems

T. Sakai*, S. Katsuhito, O. Yuichi, SINTOKOGIO Ltd., Toyokawa/Japan

Abstract

Green sand molding is one of the most common processes since this is suitable for mass

production such as automotive parts. Typical casting defects in green sand molding are

usually caused by abnormal sand properties. Sand properties correlated to casting defects

are classified following two groups; one group is those which changes drastically in a short

term such as sand temperature or moisture, and the other group is those which changes

moderately in long term such as clay content. For the first group, in order to keep sand

properties stable to feed, automatically measure the properties at short intervals such as

several minutes and control accurately are required. On the other hand, for second group,

analyze statistically about sand properties, estimate the trend of transition and then adjust

them in long term according to the estimation is required. The concept of such sand

management is incorporated in a sand treatment total system (See Fig.1). It is the first step

for making a high quality casting to adjust progressively the sand property from cooling and

keeping moisture of the return sand to the final adjustment in the muller. To configure the

accurate and multistep sand property control system, following three devices were developed.

First is the high efficiency water feeder-agitator. Second is the automatic moisture

adjustment system. Third is the inline sand test unit for measuring sand properties

automatically prior to molding machines. Authors believe that intelligent green sand

treatment system with these developments would greatly contribute to “Better casting

manufacturing” with achieving superior casting quality by stabilization and numerical control

of sand properties.

52


1. Water Feeder-Agitator

To cool green sand, vaporization heat of water is utilized. The mechanism is as follows; first,

feeds water to return sand, next, disperses it by an agitator, and then decreases sand

temperature by cooling effect on the evaporation of water in the sand cooling device. The

developed water feeder-agitator has achieved water feeding and dispersion in closed space

but processing continuously. Compared to conventional models, the developed model

generates less dust, has superior cooling ability (See Fig.2) and improves uniformity of water

dispersion.

53


2. Automatic Moisture Adjustment Unit

Usually green sand moisture content is determined with the calibration curve defined by

relationship between moisture and impedance. However, this relationship can be disordered

by change of sand composition. The developed system feedbacks the actual value of

moisture for next cycle in order to feed water accurately and supply stable moisture sand.

This system enables to feed water more accurately and appropriately than before, and then

decreases deviation of moisture.

3. Inline Sand Test Unit

From mullers to molding machines, sand properties can

be varied by external factors such as room temperature,

humidity, and plant stop, etc. However, it is very difficult to

monitor actual sand properties. Therefore, the inline sand

test unit, which samples sand automatically from a belt

conveyor before a molding machine and measures sand

properties automatically and inline (see Fig. 3). Analyzing

data measured by this unit accelerates time for eliminating

casting defects.

54


Competitiveness by Leadership - Ensuring the Competitiveness of

Foundries in High Wage Countries by Using a Clear Leadership

Model

Wettbewerbsfähigkeit durch Leaderschip – Mit richtiger Führung die

Wett-bewerbsfähigkeit der Gießereien in Deutschland sicherstellen

H. Doppler, Managementberatung Doppler, Freiberg am

Neckar/Germany

The key challenge the foundry industry is facing in highly developed economies such as

Germany is being able to produce competitively despite rising energy costs, high wages and

stringent environmental standards. Only companies that successfully develop and further the

performance of their employees, so that they dedicate their knowledge and abilities

unreservedly, can master this challenge. Business as usual no longer suffices, excellent

performance is required.

Leaders in the foundry industry must achieve this best performance in a time when the

workforce is undergoing major changes. Young employees just out of school are creative,

communicative and have an affinity for technology - not least because of the ubiquity of

digital and social media. However, they are also more critical of their employers, do not

always just what they are instructed or are less able to focus and to take criticism.

Furthermore, today’s managers often deal with a heterogeneous workforce comprised of

permanent staff and temporary workers; moreover, there is more cultural diversity.

Though it has always been a challenging task for managers to reach their employees and

move forward together, this task has become even greater. This calls for goal-oriented

leadership that reaches people. To this end the author has, based on his own experience,

developed a leadership model called "Leading with respect and persistency". This model is

based on 4 pillars and emphasizes the importance of respectful relationships and the

necessity to lead a team in order to meet challenging targets.

55


1. Be a leader

A successful leader concentrates on creating products that are of high value to the customer

and manufactures them in a profitable way. He or she monitors all relevant processes and

makes sure that procedures are being scrutinized and improved continuously. Being

proactive is important – a leader has an intrinsically motivated and proactive personality.

Leaders influence their employees not only with what they do but also with how they do it.

Respectful leadership is, among other things, about demonstrating punctuality and reliability,

and demanding the same from employees. Some consider these values to be outdated.

They are wrong however: Showing respect to others also means respecting their time

("punctuality") and respecting other people’s expectations and plans ("reliability").

2. Win employees

Winning employees requires making the right decisions and convincing employees of such

decisions. Listen, comprehend, decide and ensure implementation – that is the name of the

game. Don’t make decisions if you don’t understand the topic at hand – in this case delegate

the decision to those who do. If a decision is so important that you must make it yourself (be

responsible), educate yourself as much as possible. That is how consistent and long-lasting

decisions come about.

Once a decision has been made, it needs to be communicated to the employees in a concise

and coherent manner. A manager who does not communicate important facts about the

companies’ current context and performance in a comprehensible way takes the risk of

discouraging employees and thus jeopardizing the implementation of required measures.

The maxim is as follows: If you explain everything that you can explain, then employees will

believe the (few things) that you cannot explain. It is a trust-building exercise.

On top of that, as part of the implementation process, leaders should praise their employees

in a timely manner, when they have done something well, respectively thank them for their

efforts.

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3. Develop high-performance teams

Casting requires teamwork and best performance is achieved only in well-attuned teams

where everyone is committed and carries out their individual duties. In a team the potential of

each individual contributes to a joint effort: When strengths and weaknesses of its individuals

are known a team member’s weakness can be compensated by another team member’s

strength. A team-oriented leader rates team performance higher than individual

performances, and demands and appreciates the team effort accordingly.

4. Achieve results

In order to stay competitive companies should set themselves challenging targets. This

necessity needs to translate into ambitious targets for all the different areas. These targets

can only be met through successful cooperation between employee and leader.

Leaders should emphasize the fact that ambitious targets are not only in the company’s

interests but also the employee's. In fact, ambitious targets secure the company, the site and

thus the jobs. A high degree of perseverance is crucial. Keeping going when others

(competitors) give up.

In summary, the leadership model "Leading with respect and persistency" provides guidance

to leaders who seek to achieve optimal performance for their companies in challenging

market conditions. Apart from the here-discussed basics, the author has worked out each

pillar in great detail in different training modules, which will help leaders to grow their abilities.

57


TENSAL® - The Development of a High Strength Aluminum Casting

Alloy for the Production of Highly Loaded Chassis Components

TENSAL – Die Entwicklung eines Aluminium-Gusswerkstoffs mit

erhöhter Festigkeit für die Fertigung hochbelasteter

Fahrwerkskomponenten

Dr. rer. nat. K. Greven*, M. Loganathan, O. Grimm, KSM Castings Group

GmbH, Hildesheim/Germany

The Counter Pressure Casting (CPC) process is particularly suited for the production of

aluminum suspension components like wheel carriers or steering knuckles. Compared to

conventional low pressure casting, form filling and solidification takes place under an

increased pressure level. This leads to a significant reduction of porosity and therefor to

increased level of strength and ductility. Using a typical AlSi7Mg alloy such as EN AC-42100,

yield strength above 260 MPa and elongation rates above 8% are possible. KSM uses this

process for the series production of various chassis components like steering knuckles or

wheel carriers. To improve the competitiveness of such cast aluminum components

compared to forged aluminum or even cast iron, a further increase in yield strength is

needed.

The present work shows how this goal can be achieved by the development of a new

aluminum casting alloy. Besides the modification of Si and Mg content, the addition of Cr

leads to an additional precipitation hardening effect. In this way, yield strength above 310

MPa combined with an elongation of 7% can be assured in the CPC process after a T6 heat

treatment. Fundamental microstructural investigations as well as tensile tests, high

temperature strength, corrosion behavior and static and dynamic component testing were

performed during the material development. All results were achieved on existing

components like steering knuckles and not on casted test bars.

58


To demonstrate the weight reduction potential of the presented alloy, the product

development of a steering knuckle for a rear driven premium car was performed and

prototypes were produced in the CPC process. The static and dynamic testing of this

component fulfilled all requirements and the series-production readiness was approved.

These efforts finally result in the nomination for a high volume series production of a chassis

component. The increased level of strength enabled KSM to substitute the cast iron

predecessor and to reduce the weight significantly. This component is the first application of

the new alloy invented and patented by KSM Castings Group GmbH.

59


Productivity and Ecology Considerations of High Production CB

Processes

Produktivität und Ökologie in der anspruchsvollen Cold-Box-Serien-

fertigung

J. Archibald*, M. Hartman, J. Benavente, ASK Chemicals L.P., Dublin,

Ohio, USA

Twenty-five years ago CB binder systems were being expanded into most all high production

applications. They were chemistries that were being discovered and developed. In addition

regulations in developed countries evolved to further control sand casting operations safety

concerns and emissions from the casting process. Looking back there has been significant

improvements in the basic chemistry of the binder systems and remarkable progress in

engineering processes with-in and around the chemistry. The development of advanced

casting design services to model how cores and molds are made have made sand casting a

high tech more dimensionally accurate predictable manufacturing process versus a “black

art” 25 years ago.

We as a metal casting Industry have developed a much better understanding on how

chemistry can be leveraged in a sand casting process to take cost out in use throughout the

supply chain for finished products we create. The sand casting process developed as a low

cost option to fabrications and other casting methods to make a metal shape in a geometry

desired rapidly and more cost efficiently. The Arena Flow sand modeling methods combined

with the best materials, automation and advanced equipment can provide the solutions to

safe and efficient casting operations.

60


Looking forward as we strive for improved casting quality, productivity and environmental

compliance we cannot lose sight of the economics of a metal casting process through the

supply chain and into the final products we use in our lives that require castings. This paper

highlights the remarkable progress made in Cold box binder chemistry, and the evolution of

inorganic binder technology for the future. The sand flow modeling and the fundamental

visual understanding of the CB blowing and curing process to support optimization of tooling

and process design is critical for rapid success and implementation of the process. The

equipment improvements and automation achievements are demonstrated and key

examples from specific casting market segments including precision sand casting (PSC) of

aluminum, high production ferrous castings and dimensionally demanding casting

applications are reviewed. Lastly as we look to the future and the next 25 years of sand

casting we can imagine how we can further improve the sand casting process from a casting

quality, and productivity and environmental standpoint while still being sustainable from an

economic and environmental standpoint as a casting producer.

Keywords: Cold box processes; sand binders; equipment; computer modeling, Arena

Flow: environmental compliance hood stack emissions; productivity: Economics,

inorganic binders, and cost in use.

61


Robust Cast Product Design Driven by Front-Loading through

Virtual Experimentation and Optimization – Baseline Technology for

Efficient Development Processes

Robustes Gussdesign durch virtuelles Experimentieren mit Gießprozess-

Simulation als Baustein innovativer Entwicklungsprozesse

Dr.-Ing. H. Bramann*, Dr.-Ing. J. C. Sturm, H. Rockmann, H. J. Gaspers,

MAGMA Gießereitechnologie GmbH, Aachen/Germany

Lightweight design is a strong enabler for widening markets for castings. The requirements of

early decisions for an optimal production process in terms of weight reduction potential,

properties of the cast component, economic efficiency and robustness in particular requires

extensive product and process knowledge especially at the beginning of the development

cycle.

Enabler for this early stage decision process is “Front-loading”, the systematic transfer of

process knowledge on dependencies and occurring variations of the manufacturing

conditions into the components design. The aim of the font-loading process is to provide

information on the function, performance, technological and other properties of a product and

the manufacturing process as early as possible to responsible product engineers and

designers in utilizable quality. Considering the diversity of factors that influence the quality of

cast parts and the complex interactions of physics, metallurgy and the cast part geometry,

empirical knowledge is still the most important source on which an „optimized production

engineering“ is based.

State-of-the art casting process simulation can quantify experience providing more than just

a defined "status" but giving insights into the root cause of problems. However the iterative

setup of individual, single simulations does neither show the robustness of a design nor

whether it represents the optimum under the given conditions. In order to generate this

knowledge systematic variations of the process conditions have to be calculated using

statistical methods of virtual test planning like DoE („design of experiments“).

62


This contribution gives a short introduction on the application and potential of the enhanced

methodology of virtual casting experimentation. Systematic and automated casting process

analysis enables the transparent quantification of the influence of design decision and

manufacturing conditions on casting quality with merely unlimited degrees of freedom at

minimal risks. The combination of experience, knowledge and virtually generated process

understanding is the basis for improved decision-making structures and a cornerstone of

continuous improvement towards innovative and competitive lightweight cast components

and robust manufacturing.

63


International Foundry Challenge – Suitable Production of Thin

Walled Aluminum Prototype and Small Series Castings for Body in

White Applications

Herausforderung Guss – Anforderungsgerechte Fertigung dünnwandiger

Aluminium Prototypen und Kleinserien im Karosserbau

Dr. J. Gundlach*, Dr. J. Detering, Grunewald GmbH & Co. KG,

Bocholt/Germany

Abstract

The general requirements and the specific needs of the casting production of thin walled

Aluminum products are shown as well as an insight into the Grunewald production. As a

particular focus the significance of technical and human interfaces in an integrated casting

production is pointed out by 2 examples.

1. Starting Point

Our international operating foundry faces to market changes and challenges, forced by Light

Weighting and Rapid Manufacturing. As a medium seized, family owned business Grunewald

focusses on various technologies and applications in order to gain technology leadership in

tooling, casting of Alumimium components and composite processing and to provide

attractive solutions to our customers.

Within Grunewald`s different areas we transfer Know How and benefit, e. g. from aerospace

carbon composite applications into automotive solutions. These technology transfer

opportunities enable innovative and cost efficient solutions.

64


Increased requirements regarding the product and process quality of casted prototypes and

volume production in terms of functional, thin walled geometries including series properties

have to be realized in casting product developments and production.

2. Goal – Complete Solutions from a Concept to Small Series Production

Bodies in white concepts take more and more castings into account. Casting joints and other

structural castings are used in all areas of a car body. In order to realize the defined

properties the low pressure casting technique and an integrated casting product and process

development are mandatory. The whole process chain of design, tooling, casting process,

heat treatment, straightening and NC-finished part processing needs to be carefully adjusted

in order to increase the efficiency in cast aluminum prototyping and to reach a higher grade

of validation regarding weight and mechanical properties.

3. Practical approach in the development and production of body in white castings

Simultaneous development, technical and human interface management and innovative

technologies of tooling, prototyping, pre-series and series production are shown regarding:

thin walled casting design

intelligent tooling

raw part precision with low pressure casting

adjustment of shrinkage and distortion

specific mechanical properties

interface Management

Picture: Low Pressure Sand Casting AlSi7Mg0,3 T6 - Shock Tower - Mercedes-Benz

65


Literature

1 Gundlach J., Detering J.: Anforderungsgerechte Fertigung dünnwandiger, gegossener

Aluminium Prototypen und Kleinserien im Karosseriebau,

Landshut 2011, in leightweight design 5/2011, Seite 48 – 52

2 Röth T., Müller G., Gundlach J.: Einsatz von Gussbauteilen in einem

Karosseriebaukasten für Kleinserienfahrzeuge, Aachen 2012

3 Fang X., Gundlach J., Azim E.: Hybridgießen von Aluminium und Stahl zur

Herstellung von Verbindungsknoten für eine MIschbaukarosserie,

Landshuter Leichtbaukolloquium, Landshut 2015

4 Weiß, K.: Temperaturfeldberechnungen bei Erstarrungsvorgängen unter

Berücksichtigung des Einfüllvorgangs (Dissertation), Fakultät für Bergbau,

Hüttenwesen und Geowissenschaften der Rheinisch-Westfälischen Technischen

Hochschule Aachen, Aachen 1986

5 Honsel Chr.: Die Berechnung von Wärm- und Eigenspannungen infolge von

Abkühlungsprozessen mit der Methode der tangentialen Steifigkeiten (Dissertation),

Fakultät für Bergbau, Hüttenwesen und Geowissenschaften der Rheinisch-

Westfälischen Technischen Hochschule Aachen, Aachen 1992

6 Gundlach J.: Betriebliche Weiterbildung in der Gießereiindustrie, theoretische und

empirische Untersuchungen aus technikdidaktischer Sicht, Otto-von-Guericke-

Universität Magdeburg, Magdeburg 2000

66


Methodical, Automatic Optimization of the Casting Process

in Terms of Economy, Resource Efficiency and Wuality

Methodische, automatische Gießprozessoptimierung auf

Wirtschaftlichkeit, Ressourceneffizienz und Qualität

P. Kohlmeyer, G. A. Röders GmbH & Co. KG, Soltau/Germany

The predictions of the results of a die casting process using a filling simulation are generally

accepted by now. For about 15 years there are ways to connect the filling simulation,

solidification, mechanical properties and stresses in casting with mathematical optimization

methods. The advances compared to normal simulations are mainly the results of optimized

casting conditions and the determination of the influence of individual parameters on

technical and economical outcomes.

This article is about how the entire gating of a die casting tool with two cavities was optimized

in regard to accurate parts and a minimum use of circulation material. At the same time it

should be demonstrated up to what extent round runners in aluminum die casting are

feasible and useful. Therefor possible options of designs of the gating were constructed as

parametric geometries in 3D CAD. A number of options were compiled in a DOE. The

different designs were automatically simulated and evaluated with MAGMAfrontier. For the

results of this methodological approach we received an award at the International German

die casting day 2014.

Furthermore it is shown how MAGMA 5.3 reduces effort due to a higher amount of variants

and evaluation options.

It follows an outlook on the application of this technology in regard to the die casting process

layout of a medium-sized foundry and the commercial outcomes.

67


Development of a Novel AlCu-Cast Alloy for Thermally High Loaded

Cylinder Heads

Eine neue AlCu-Gusslegierung für thermisch hochbelastete

Zylinderköpfe

Dr.-Ing. F. J. Feikus*, Dr. L. Kniewallner, Nemak Europe GmbH,

Frankfurt/Germany; M. Rafetzeder, Dr. M. Djurdjevic, B. Stauder, Nemak

Linz GmbH, Linz/Austria

This article describes the successful development of a novel AlCu7MnZr alloy for cylinder

heads that is characterised by very high strength at elevated temperatures. In general AlCu

alloys provide the highest potential in mechanical strength at temperatures above 200 °C.

Though, due to their tendency to hot crack formation and restricted feeding ability the

applications are strongly limited to small volume production only. Driven by an intense R&D

effort Nemak managed to develop the optimum alloy composition and adapted the melting

and casting process accordingly for this new cast alloy AlCu7MnZr.

With regard to mechanical properties the hot tensile strength of this new alloy after 500 h

thermal pre-conditioning has to be highlighted.

Hot tensile strength of the alloy

AlCu7MnZr (T6 water quench) after 500 h

pre-aging at test temperature compared

to AlSi(Cu)-standard alloys.

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Thermal conductivity AlCu7MnZr

compared to AlSiCu-standard alloys and

AlCu4Ti

To assure the engine relevant demands thermo-mechanical properties of cylinder heads

were investigated. Significant improvements were achieved with the new alloy compared to

standard alloys.

Supplementary investigations on thermo-mechanical fatigue properties of test specimens

confirmed the excellent results that were obtained from cylinder head testing. Based on

these results operating temperatures clearly above 250 °C will be covered by the

AlCu7MnZr.

To secure production technology various complex petrol and Diesel heads were cast in the

Rotacast ® and gravity permanent mould process. It can be stated, that design standards

and existing engine architectures do not require any substantial changes.

For future successful product launches it is a necessity to combine the acquired casting

know-how with the opportunities of the casting simulation. The knowledge of the fraction

solid as a function of temperature in the solid liquid regime is of essential importance. Nemak

currently supports the further development of simulation algorithms.

Tests with specimens, components and engines have proven the advantages of the new

alloy. To provide first AlCu7MnZr cylinder head castings existing tools can be used at any

time.

69


Lightweighting the Right Material at the Right Place - A Comparison of Iron, Aluminum, Magnesium and Carbon Fiber Leichtbau: Das richtige Material am richtigen Platz: Ein Vergleich zwischen Eisen, Aluminium und Karbon K. Decking*, M. Holtkötter, Georg Fischer Automotive AG, Schaffhausen/Switzerland

Engineers have a choice to make when it comes to reducing weight. Castings with steel, iron,

aluminum or magnesium are only a few of several different options. Carbon fiber is being

discussed as an optimal solution to gain weight.

A direct comparison of several factors such as weight reduction, costs, joining technologies,

performance, life cycle assessment between carbon fiber and castings show that every

material has its right place and that castings are a prime solution when it comes to

lightweighting and Passion for a Lighter Future.

1. Lightweighting Potential

When it comes to lightweight potential among different materials, car manufacturers in recent

times often think about carbon fiber as the best solution. Excellent material characteristics in

the case of tensile strength, stiffness, Young's modulus and density and the light weight play

an important role in the process of choosing the best solution. It is often forgotten, that

materials already proven in serial production can have the same positive impact on weight

savings:

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Table 1: Lightweighting Potential of Steel, Aluminum, Magnesium and Carbon

Composites

2. Production Process & Sustainability

No matter whether castings or carbon fiber, both materials require a medium to high amount

of resources and energy during the manufacturing process. Especially magnesium and

carbon fiber are known to be resource intensive. With a change of perspective, some

resource intensive materials can have a positive ecological balance during their life-cycle,

whilst others have not. Material availability and recyclability are also important factors to be

considered.

3. Freedom of Design

New developments in casting techniques and design, creating thinner and stronger

structures as well as the development of new materials have opened new fields of

applications for castings. Carbon fiber has far more limits when it comes to shaping and

designing parts.

4. Costs

Today, carbon composites are known to have an up to three times higher cost level than

aluminum and magnesium solutions. Even in 2020, the costs for carbon fiber will exceed

existing serial casting solutions by far.

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Table 2: Part Production Cost in Reference to Steel

Conclusion

Choosing the right material for lightweighting is complex and depends on several factors.

Ever material has its right place. At the end it is not a question of which material but of how to

join all the different material.

72


Energy Balance and CO2 Emissions Study for the Total Life Cycle of

Engine Blocks Produced from Aluminum and Cast Iron

Studie zur Energiebilanz und CO2-Emisionen von

Zylinderkurbelgehäusen aus Aluminium und Gusseisen

Dr.-Ing. A. Sobota*, W. Görtz, Eisenwerk Brühl GmbH, Brühl/Germany

Summary

1. Objective

The purpose of this study is to identify the amount of energy needed and the equivalent CO2-

used the manufacturer of cast iron and aluminum Cylinder block castings and their use in a

passenger car. At first we will determine how much energy and CO2 emissions are used in

the manufacturing phase and then we will determine the break-even point in the utilization

phase of the vehicle in relation to the cast material and casting method.

2. Source

Extensive research has made it possible to calculate the energy input and CO2 equivalent.

The results from this investigation show a global availability of less than 20 % for secondary

(recycled) aluminum [1]. In Germany the content of secondary aluminum is about 30%. Due

to increased global demand it is expected that the total future available quantity of secondary

aluminum in Germany, will not exceed the 30 % [2]. Several sources show only one-tenth of

the energy is needed to prepare secondary aluminum in comparison to primary aluminum [3,

4, 5]. For the energy assessment we have used operating data from iron and aluminum

foundries [6, 7]. The energy demand for transport of rough material (in), and products (out) or

waste (out) was calculated with average numbers.

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3. Calculation criteria

The following assumptions were made to calculate the energy demand and the CO2

equivalent for the manufacturing phase as well as for the utilization phase of a passenger car

application with a cast-iron and aluminum cylinder block

Energy demand to prepare the rough material.

Energy used in the foundry and machining.

Transport of material and products.

The cylinder block is used in a passenger car application with a gasoline engine

For the utilization phase we compared an engine with a cast iron cylinder block (32 kg) to an

aluminum cylinder block (24 kg). Due to different engine structures we assume that from

11 kg weight difference in the parts, about 8 kg weight difference remains for the complete

engine. To calculate the break-even point in the utilization phase we assumed a fuel saving

of 0,25 l per 100 km and 100 kg weight reduction.

4. Results

Based on the sources and calculation criteria we have calculated the break-even points for

engines with cylinder blocks made out of iron sand castings, aluminum HPDC (high pressure

die cast), aluminum LPDC (low pressure die cast), aluminum sand castings CPS (core

package).

Fig 1: Break-even for the CO2-equivalent for cast iron and aluminum cylinder blocks depending on the

manufacturing method

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With a share of 30 % secondary aluminum, the break-even point between a cast iron cylinder

block and an aluminum HPDC block is calculated at a mileage of 480.000 km (Fig. 1). The

break-even point moves to 515.000 km respectively to 600.000 km for aluminum die casting

or aluminum core package sand casting, due to a higher energy demand for manufacturing.

According to investigations of the German “Kraftfahrt-Bundesamt” from 01.01.2014 the

average lifetime of a passenger car is 8.8 years [8]. In 2013 the average mileage in Germany

for a passenger car was 11.800 km [9]. In Germany the total mileage of a (gasoline)

passenger car is 103.840 km in 8.8 years.

5. Summary

The results of the study show a much higher energy demand and CO2 emissions for the

manufacturing of aluminum cylinder blocks compared to cast iron. The benefits in the

utilization phase due to fuel saving have a relatively small influence on the total balance.

Depending on the

amount of secondary aluminum and the manufacturing method, the break-even point moves

up to 600.000 km.

To achieve a break-even for the CO2 equivalent with an aluminum HPDC cylinder block the

foundry would need a min. of 75% of secondary aluminum, for the average mileage of

103.000 km, i.e. the average total mileage of a German passenger car in its full lifetime.

Statistics an forecast on the availability of secondary aluminum show a percentage below 30

% for the manufacturing of engine components in Germany. In all the discussions on CO2

reduction, governments should also consider the manufacturing of products and not only

focus on the utilization phase.

76


Comparing the Foundry Industry in the United States to Europe

D. Trinowski, Hüttenes-Albertus Chemische Werke GmbH,

Düsseldorf/Germany

This presentation compares the EU and US foundry industries as it pertains to molding methods

and materials.

It discusses what drives innovation in the metalcasting industry, particularly as it pertains to

methods and materials and differences between Europe, primarily Germany, and the US.

Other topics covered:

‐ General Metalcasting Comparisons

‐ Molding & Core Making Methods

‐ Molding & Core Making Materials

‐ Binder, Coating, G/S Trends

‐ Environmental & Regulatory Impacts

‐ Emissions TradingSummary

77


Radio Frequency Identification for use in No-Bake Foundries

C. Wilding, Omega Foundry Machinery Ltd. Peterborough/UK

RFI has been used by Omega for many years now but over these years the system has developed

and improved. This paper will explain how RFI works and how it has evolved by demonstrating

what additional benefits can be obtained by the no-bake foundry.

IRIS

The IRIS (Intelligent Radio Identification System) system consists of three main components, the

RFI (Radio Frequency Identification) tag itself, the antenna and the HMI interface with industrial

PC.

The RFI tag is a relatively low cost and durable component that can be re-written many times (fig

1). The small size means that it can be installed into the pattern with relative ease and

convenience. The short range antenna is usually sited at the mixing station close to the

compaction table and protected by a Perspex case (fig 2). Finally, the HMI interface with industrial

PC is the heart of the system that stores the data (recipe) to be used by each tag. The HMI is

usually located in the main plant control panel, away from the immediate moulding area. The HMI

is also the means through which the operator can read or write information to the tag or recipe.

Production data can also be obtained directly through the interface itself.

Fig 1

Each pattern will have an RFI tag fitted, the tag is usually inserted into the wooden pattern plate

via a 6mm hole and sealed with silicone. The pattern, with a new tag installed is then placed on

the compaction table so that the antenna can communicate with the tag and the relevant recipe

can be loaded. The operator will then set the recipe parameters via the touch screen interface,

the typical recipe parameters will be as follows:

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1. Fill Time – The time that the mixer will deliver mixed sand into the pattern. (Usually

determined by trial and error to give exactly the correct amount of sand).

2. Run to Pause – The time at which the mixer will pause to enable the operator to place

chills or loose pieces (optional).

3. Resin Addition as a %

4. Sand Type – New, Reclaim or Blended sand (or other types such as Chromite).

5. Set Time - Catalyst or Hardener Addition as a %

6. Compaction Table Lift Time – Duration of vibration

7. Compaction Table Frequency – Vibrator motor running frequency to determine amplitude.

8. Tag ID – A number or name for the tag that relates to the mould for identification purposes

Fig 2

Once the relevant data has been added, the operator presses the ‘Write’ button and the tag ID and

recipe are connected. This operation need not be carried out again unless any modification is

required for the recipe.

The next time that the pattern comes to the compaction table, the operator presses a start button,

the antenna reads the tag ID and relates that number to the relevant recipe stored in the central

plc. The mixer then starts automatically and together with the compaction table, delivers the exact

sand mix recipe to the pattern at the exact frequency and time of vibration. No sand is wasted and

the operator simply has to strickle the sand to smooth the back of the mould.

IRIS also has the facility to display a job card on the main screen (fig 3), this will show a picture of

how the pattern should look – with chills or loose pieces shown in the correct positions plus any

other specific instructions for producing the mould.

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Fig 3

Each consecutive pattern brought to the mixing station by the moulding line will be automatically

recognised by its unique tag ID, filled to the exact recipe, compacted and logged in the system

with minimal operator involvement.

It is also important to note that the antenna will not read a tag through a metallic flask, so in the

case of metal flasks, a wooden block with the tag inserted can be attached to the edge of the

pattern plate.

Taking RFI Further

There are many possibilities to utilise this technology still further. Not only moulding but core

making can be included. The RFI tag can be inserted into any wooden corebox or wooden backing

plate, the antenna installed into the coreshooter and a unique recipe given to every tag. The

recipe would consist of corebox position within the clamping system for auto clamping, gassing

time/pressure and purging time/pressure. Also the number of cores produced is logged in the

system.

The facility to network the RFI system on each individual mixer and coreshooter to the main

production office server is also possible. The data logging software is loaded onto the server and

onto the production supervisors computer, this enables the supervisor to access real-time

information from his or her personal computer (pc) giving real-time details of the current mould or

core being made, total days production to date and previous days, weeks or months of stored

production data (fig 4). So not only are we logging the numbers of moulds and cores made, but

due to the detailed recipe information we are able to calculate the total volume of raw materials

used on each mould or core, the cost of each individual mould or core and even the cost of each

individual casting (fig 5). Of course, in this case there is a requirement for the foundry to enter into

the system details of raw material costs, manpower and various other overhead costs.

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Fig 4 Fig 5

Conclusion

All production data can be stored on a hard drive or CD in either Excel, Microsoft Word or pdf

format for storage and future access, giving total traceability for each mould and core made.

Patterns with tags fitted can be stored for long periods of time without use, brought back into

production and without any further calculations be put straight back onto the line as the recipe is

stored in the HMI as the antenna will immediately recognise the tag ID.

There are various foundries already using this growing technology throughout the world, reaping

the associated benefits from such a system.

But more foundries should embrace this kind of proven technology to give them the competitive

edge they need in the castings market as well as ease the workload on already overstretched

foundry personnel.

So by using the RFI system the foundry is utilising the latest process technology to meet the

challenging demands of today’s casting buyer.

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Novel Urethane No-Bake Binder For Reduced Smoke and Odor

S. Trikha, Hüttenes Albertus

Phenolic-Urethane No-Bake binders are widely used for molding and core-making to produce

ferrous as well as non-ferrous castings in North America. One of the drawbacks of the process is

the use of petroleum based solvents that carry the polymer in the finished resin. The use of these

solvents works well, but cause odor and smoke during pouring, cooling and shakeout. Foundries

are subject to environmental pressures from various perspectives such as MACT standard, Area

Source Legislation, Permit Issues, Nuisance Odors, and Work Exposures. Therefore, there has

been a demand to make these binders environmentally friendly.

A new generation of solvent is discussed that reduces emissions, odor and smoke during the casting

process. A program of work was undertaken at a university to compare the emission characteristics

of the new binder to the conventional binders. The findings of that work are reviewed in detail. The

performance aspects such as reactivity, strength development, and hot strength of the new binder

are reviewed. The conversion of a ferrous foundry to the new binder is discussed. Their

experience of a reduction in binder level with the new binder is presented.

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RAPID DEVELOPMENT OF EXPORT CASTINGS IN OUR FOUNDRY BY

SIMULATION TECHNIQUES – SOME INDUSTRIAL CASE STUDIES

T. Roy, Texmaco Rail. Kolkata/ India

ABSTRACTS

This study reports an in house experience of the rapid development of new castings in our foundry

by simulation techniques along with some industrial case studies.

This is also a detailed and step by step process of developing the export castings right from the

tooling development to method and process standardisation by using 3D modelling software and

casting simulation software.

To cope up with the stringent quality requirements of international customers, pilot samples are

produced on computer screen to visualise and predict the defects which may occur in practical

situation and taking corrective action and again verify the results. Until the model casting found

defect free.

After that this method or process is implemented in practical situation under close observation of

the process parameters.

Customer will no longer accept high levels of scrap, long lead time and so casting simulation

become an industry standard to develop new casting in a short period of time with lesser number

of trials.

In this paper the rapid development of American bogie castings (side frame and bolster) as per

AAR (Association for American Rail Roads) standards and development of some mining castings

are described thoroughly with the help of simulation results and industrial case studies.

We have seen that in bogie castings which are box type constructions, hot tear defect is very

common and serious defects which impair the soundness of the castings. Another serious defect

is shrinkage at the junctions of ribs.

These two defects are well identified by using simulation and suitable corrective actions taken can

be verified by simulation results.

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Another serious problem in this type of steel casting is sand sticking defects at the bottom and

corners of ribs or junctions.

Apart from that the cold shut at the pedestal leg or air entrapment at the bolster opening or

pedestal leg areas can be easily identified and resolved by taking suitable actions with flow

simulation results.

Apart from that the control of casting weight is another important factor for bogie casting. So, by

designing suitable method to control weight and by proper design of core box and pattern and

ultimately verify the casting weight by modelling software.

In mining castings produced for overseas customer, cold shut, air entrapment and scab defects

can be easily solved by flow simulation and shrinkage defects by solidification simulation results.

With the help of simulation techniques it took only two weeks (only two trials) to make defect free

bogie castings and similar time for each type of mining product.

So, good methoding practice adopted to eliminate potential defects in our steel foundry is well

verified by simulation results.

Key words- Hot tear, Shrinkage, Air Entrapment, Flow simulation, solidification Simulation, Cold

Shut, pedestal leg.

84


Improving Casting Quality and Productivity Through the Application of

a High Efficiency, Engineered Lustrous Carbon Former

N. Richardson, IMERYS MetalCasting Solutions, United Kingdom

V. LaFay, IMERYS MetalCasting Solutions, United States

Copyright 2015 World Foundry Organization

ABSTRACT

A properly designed lustrous carbon former for the foundry industry can be engineered through the

selection and blending of high efficiency coals. A specifically designed blend of coal will result in

improved casting quality whilst offering significant reductions in the consumption of additives, due

to an increase in lustrous carbon content. This paper will demonstrate how the conversion of a

sand system was performed in two stages. During the first phase of product introduction, the focus

was on controlling additions of both bentonite and LCF to maintain a consistent mould atmosphere,

allowing changes in composition to be evaluated for effectiveness. The high efficiency carbon

additions were controlled via the Loss on Ignition test and were reduced in increments of 0.5%

until the level deemed to provide both optimum casting surfaces and good shakeout was reached.

These conversions resulted in improved casting quality that was measured in scrap reduction and

improved productivity.

THOMAS DUDLEY

The company was founded in 1920 and remains a family owned and managed business. Thomas

Dudley operate two UK foundries in the West Midlands equipped with state-of-the-art Disamatic,

Kunkel Wagner and airset moulding lines offering the unique ability to select the most suitable

production platform for each project allowing castings to be produced in the most cost-effective

manner. A commitment to investing in technology and people enables Thomas Dudley to deliver

the complete casting service encompassing full design and development, with in-house

patternmaking in their Advanced Centre for Engineering. Thomas Dudley offer a true single source

solution for castings in grey, ductile, austempered ductile and SiMo irons. The commitment for

investment saw the first Disamatic 2110 vertical moulding line installed in 2010 with a further 131Z

model following in 2012. The machines capability to produce a larger mould size up to 750 mm in

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width was of particular interest for Thomas Dudley; they already produced a range of fire door

castings for the domestic UK market but their appetite was to enter the lucrative European market

due to volumes. To compete in this market, surface quality is of the utmost importance with any

imperfections on the cast surface detrimentally affecting the finished product quality. A necessity

to produce castings for multiple applications on the same moulding lines with a common sand

system meant a compromise had to be made with sand quality to allow the flexibility demanded by

production. As a result of this compromise while other families of castings enjoyed a rejection rate

averaging 1 per cent, surface quality of fire door castings was inconsistent with a high incidence of

inclusion and penetration defects. In order to try and improve surface quality, the silica distribution

was manipulated with the granulometry of the moulding sand made finer, green sand volatiles had

been increased up to 2.5 per cent through additions of coal dust, with loss on ignition levels (L.O.I)

typically running at 7 per cent, in an effort to increase the quantity of lustrous carbon generated.

Despite these measures Thomas Dudley were unable to achieve the necessary quality demanded

with individual castings having a rejection rate of up to 100 per cent. Exasperated by these

problems, in 2013 Thomas Dudley made contact with Imerys Metalcasting solutions, formerly IKO

(S&B Industrial Minerals) for help.

PROCESS EVALUATION

Before any material proposal was made a full analysis of the process, additives used and

moulding sand was undertaken.

CONCLUSIONS

Selected blending of different coal dusts creates superior performance.

Correct sizing and grading of carbonaceous products for each individual application has

significant advantages, i.e. one size does not fit all.

Increasing the formation of lustrous carbon and volatile content of carbonaceous products

enhances surface quality

Enriched coal products allow for reductions in the consumption of materials.

Selective grading of materials is paramount to ensuring optimum performance of carbonaceous

products

The careful selection of green sand additives will allow a foundry to use less moisture in the

foundry’s prepared molding sand that will support the casting reduction initiative.

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REFERENCES:

1. Richardson, N., LaFay, V.; Why Iron Castings Need Sea coal, Foundry Trade Journal,

December 2014.

2. Manual of Casting Defects, S&B Industrial Minerals GMBH, 2009

ACKNOWLEDGMENTS

IMERYS Metalcasting solutions would like to extend their gratitude to Thomas Dudley for their kind

permission in allowing us to write and reproduce this paper and data

87


Proven Odor and VOC Abatement in Foundries

Bewährte Geruchs- und VOC-Abreinigung in Gießereien

C. Mülleder*, M. Klimisch, Dr. M. Krenn, CTP Chemisch Thermische

Prozesstechnik GmbH, Graz/Austria

Abstract

Odor and VOC Emissions seem to be a pending problem for foundries, becoming more

evident where living areas merge with industrial areas. It was 25 years ago when CTP

implemented the first RTO for pouring and cooling gas emission treatment in an Austrian

foundry. The utilization of hot gas for sand reclamation and warm water made it highly

economic. The fact that this system is still in operation and many other foundry projects

followed is pointing out the robustness of the system as well as the low operation costs.

Within the frame of the EU project Odorless casting [1], emission balances have been

performed at seven different European aluminum, steel and iron foundries. Cleaning

efficiency measurements within this project revealed that the RTO has by far the highest

odor and VOC cleaning efficiency of the tested abatement technologies. CTP has developed

a prototype Regenerative Thermal Oxidizer, capable to treat VOC and odor emissions from

all processes in foundries, like melting, pouring, molding but also including core shooting and

curing or sand reclamation. This is made possible with an integrated SCR catalyst, where

any NOx formed during combustion of amines is reduced to elemental nitrogen.

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1. Approach for economic solution

The long history of foundry business is probably the main reason, why the layout of many

foundries looks like it is in many cases. Huge workshops with big height and little separation

for easy access with the roof crane and plenty of air inlets as well as roof ventilators, keeping

the

work place temperature moderate and the work place concentrations below the legal limits.

Because of the regulation of the dust emissions, typically dust filters and in case of cold box

emissions amine scrubbers are employed for waste gas treatment.

For economic odor and VOC treatment it makes sense to think about possibilities for:

separation of production steps (optimum room height and size)

housing of the pouring line and cooling area but maintaining accessibility

heat recovery for sand reclamation, furnace air preheating and warm water

pre-concentration by adsorption

2. Approved solution

Meanwhile many references (Fig. 1) are proving that it is economic to apply an RTO for

treating odor emissions from foundries, when the issues above are considered. The

investment costs for an RTO are justified by the very high VOC cleaning efficiency above

99.5 %, reliability and low operating costs, especially for an organic C range between 50 and

500 mg/Nm³ typical for pouring and cooling gases. Further enrichment and flow reduction is

possible with the measures described above.

Fig. 1: RTO at Riken Castec 74,250 Nm³/h Fig. 2: Prototype RTO-i-SCR for 400 Nm³/h

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3. New Prototype

A Prototype RTO (Fig. 2) with integrated SCR catalyst (RTO-i-SCR) was developed to

remove any NOx formed in side reactions during oxidation from amines.

In this way an additional amine scrubber with all its disadvantages is not necessary and the

energy content in the emissions from core making and curing can be fully utilized in the RTO.

[1] Odour and hazardous emission abatement of foundries, LIFE10 ENV/FI/059,

http://odorlesscasting.com/deliverables/final-reports-1

90


Determination and Assessment of Volume Defects in Aluminium

Castings by Means of Computed Tomography

Bestimmung und Bewertung von Volumendefiziten in Al-Gussstücken

mittels Computertomographie

Dr. B. Oberdorfer*, D. Habe, Dr. E. Kaschnitz, G. Schindelbacher,

Österreichisches Gießerei-Institut (ÖGI), Leoben/Austria

Typical casting defects such as shrinkage cavities and porosities arising from volume

contraction and outgassing during solidification are known to deteriorate the mechanical

properties of castings massively. In contrast to common non-destructive test procedures like

radioscopy or metallography computed tomography (CT) permits three-dimensional defect

detection drawing increasing interest over recent years. However, this technology cannot be

used to its full extent due to missing standards for the assessment of CT data regarding 3D

defect distributions and their correlation with mechanical properties.

In the course of this study samples of different aluminium alloys were produced by high

pressure die casting, analysed for porosities with CT and tested in tensile and fatigue tests.

For a software-independent porosity analysis a reference body with known void volume was

designed permitting the determination of an adequate threshold between the grey scale

value of the material and that of a pore. Accordingly, both the total and the maximum local

volume porosity were obtained. A distinct correlation between the local volume porosity and

certain mechanical properties was observed. Taking into account the porosity shape and

distance to the sample surface this correlation was partially improved.

On the basis of these analyses a quality factor has been defined, with which aluminium

castings can be classified into different porosity classes. With this methodology the present

investigation contributes to a standardized assessment of volume defects by computed

tomography.

91


Simulation-Aided Optimization of Gating and Feeding Systems

for Aluminium Sand Castings

Applying of virtual experimentation with DoE technology

Simulationsgestützte Optimierung der Gießtechnik für Aluminium Sandguss Dr.-Ing. G. W. Dieckhues*, H. Rockmann, Ohm & Häner Metallwerk GmbH & Co. KG, Olpe/Germany Abstract

One of the main topics in aluminium sand casting is the optimisation of gating and feeding

systems to avoid casting defects caused oxide formation during filling. The presentation

shows the systematic approach to optimize a given layout causing a high scrap rate. By

applying a state-of-the-art DoE technology numerous geometrical influence parameters could

be analysed to find a new design for a substantial improvement of the production efficiency.

1. Topic

Development processes in the foundry are subject to growing demands caused by the

international competition. Especially in jobbing foundries the production needs to be

continuously improved to maintain and further develop the current market position. An

ongoing challenge is the efficient design and layout of casting systems both technically and

also with regard to costing.

The utilization of standard layouts based on fixed design rules is a common method to

reduce efforts for repeated sampling in the development process. Sometimes just the

application of standards is not a successful approach and a specific layout is needed to cope

with particular requirements. Beyond the common procedure of simulation the latest tools of

virtual optimisation of casting layouts can successfully be utilised to support the complex

process of a specific optimisation without a need for ineffective and expensive trial- and-error

loops.

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2. Case Study

The main challenge in aluminium sand casting is the formation of oxide layers during filling

and the resulting visible contamination of the casting surface. Common casting defects of

this kind are primarily caused by imperfections in the casting layout. Various geometric

features of the gating and feeding system are potential actuators for turbulent flow and may

cause extensive air contact layers as resources of oxides.

With a currently used standard gating layout, a four-fold pattern of a gearbox cover is

showing distinctive oxide inclusion related defects in visible areas of the component. To

improve the situation, virtual optimization was used and the runner geometry was

automatically varied and analysed based on various quality criteria. The initial examination

allows a quantitative assessment of different influencing design and process parameters.

The results also showed, that a modification of the runner design only did improve the filling

as such but did not result in an optimal solution with respect to inclusions.

Based on the best runner layout, the additional variation of the feeders and the gates using a

systematic virtual experimentation coupled with the statistical methodology of Design of

Experiments (DoE) are showing a much better filling behaviour compared to the original

standard design.

The use of DoE and virtual optimization automate and reduce the simulation efforts

significantly and simplify the evaluation. The influence of particular parameters on the various

improvement criteria can be shown and even be quantified. As a result the complex

correlation of the parameters involved can better be judged and dealt with before the first

casting is made.

93


Simulation in Support of the Development of Innovative Processes

in the Casting Industry

Simulation zur Unterstützung der Entwicklung innovativer Prozesse der

Gießtechnik

Dr.-Ing. M. Todte*, Flow Science Deutschland GmbH,

Rottenburg/Germany; Dr. A Fent, H. Lang, BMW AG, Landshut/Germany

Abstract

The paper illustrates the application of simulation for the development of innovative casting

processes at BMW Light Metal Foundry in Landshut and other foundries.

1. High pressure die casting of complex structural parts

Complex structural parts are very demanding with regard to the HPDC process and the

tooling concept. BMW performs a detailed analysis of the complete process incl. the filling of

the shot chamber, modelling of the piston movement applying PQ² diagrams, solidification,

cooling and the calculation of residual stresses.

2. Inserts in high pressure die casting

The casting simulation software FLOW-3D was used for the analysis of the influence of

inserts on the filling pattern and the infiltration of the inserts.

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Figure 1: Filling pattern of a complex structural part (BMW i3) (left) – Gravity filling process

using a innovate moving ingate system (right)

3. Innovative ingate systems for gravity casting

The newly developed Injector Casting process of BMW combines the advantages of

traditional processes (top pouring, bottom casting) and avoids their disadvantages by

applying a moving ingate system. It greatly reduces casting defects due to turbulence and

oxide generation. Amongst others, advantages are that the risers are filled with hot melt at

the end of the filling process and that the cooling of the bottom plate can be active during the

entire filling process which is beneficial for the control of the properties of the structure.

FLOW-3D was used for the optimization of the design and movement of the ingate system.

4. Core blowing and core drying for sand cores with inorganic binder systems

The Light Metal Foundry of BMW substituted conventional organic binder systems for sand

core production by eco-friendly inorganic binders in 2010. The introduction of this innovative

production method was facilitated by simulations of the shooting and drying process of the

cores with FLOW-3D.

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5. Application of salt cores in high pressure die casting

Hitherto it has not been possible to produce castings with cavities using the HPDC process

because conventional sand cores do not withstand the high pressures and velocities

characteristic for the process. Salt cores are a solution for this dilemma due to their superior

stability. The fluid-structure-interaction option in FLOW-3D allows to simulate the interaction

of melt and salt core, specifically the high forces on the cores during the filling process and

the thermally induced residual stresses during the solidification.

Figure 2: Simulation of a core blowing process (left) – Stresses inside a salt core

(specimen, courtesy Bühler AG) during HPDC filling process (right)

96


Economic and Energy-Related Aspects of Batch Planning and the

Optimization of Melt Operations

Chargenplanung und Optimierung des Schmelzbetriebs unter betriebs-

wirtschaftlichen und energetischen Aspekten

K. Bembenek*, Dr. H. Ortloff, K. Herzog, S. Recktor, RGU GmbH,

Dortmund/Germany

Although the melting shop is by far the most cost-intensive user of materials and energy

when it comes to producing castings, it usually only plays a subordinate role in most

ERP/PPC-systems. Usually the melting shop is considered as an internal supplier that has to

deliver a defined quantity and quality of liquid melt on time. This means that the profitability of

the moulding shop and the pouring process heavily depends on the performance of the

melting shop.

With steadily increasing energy costs, the demands placed on the operators in the melting

shop have also been increasing accordingly. In recent years, RGU has been developing and

delivering solutions to provide even better support for the smelters in the foundries. These

solutions have been successfully implemented in a variety of foundry projects with focuses

on the following:

‐ Batch and furnace-allocation planning – as a component of mould and cast

planning

Various solutions exist to meet the requirements of single unit production, serial

production and also to deal with different groups of materials.

Capacities for melt-related aggregates, energy requirements and technical restrictions

such as material changeovers, ladle use and availabilities all have to be taken into

account here. The provisioning of the liquid melt can be displayed either as a single

step process (melted and ready to pour) or as a multi-step process (basic melt,

melting furnace, ladle or converter treatment, holding furnace, pouring furnace etc.).

97


In serial production the amount of liquid melt needed for each period/hour is

calculated according to the box weight and the cycle time in the moulding plant and is

then compared with the melt capacity. Energy needs are subsequently derived from

the mould plan and contrasted with the load management. Special requirements also

have to be considered when planning mass or composite castings when castings

from several furnaces or ladles have to be synchronised.

‐ Calculating the charge – most cost effective recipe for the materials in use

Optimisation programs can be used to work out standard recipes for the different

target analyses for materials and they can also work out charge-related batch orders

and material reservations. This task cannot be carried out sensibly without computer

support as it involves comprehensive parameter controls and interaction. The

calculations are based on the latest materials prices which are then archived for long

term evaluations.

‐ Comprehensive materials database in this ERP system for foundries

The materials data includes the properties and target values of each material and a

description of how to produce the appropriate melt. The master data regarding the

heat, cycle and swarf for each material, and the material test plans with both standard

and customer specifications relating to analyses, mechanical values, annealing

procedures etc, are all managed in the central database and not just in excel files or

text documents.

‐ Melt process and melt report

For the smelters, the most suitable post charge mix is calculated directly at the

furnace based on the current state analysis, and the whole procedure of the melt is

tracked according to the relevant process data. This is done by taking advantage of

all the possibilities which result from linking the furnace controls with the measuring

devices and by adopting and evaluating SPS data to document and track the melt

process. Any deviations, such as error messages, which occur during the process are

recorded and immediately forwarded by text message or email, for example.

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‐ Seamless materials management

It is absolutely essential to be able to track any incoming goods as well as the

consumption of materials and the material flows for the melt. It is not only the

quantities which play an important role here, but more and more it is about being able

to allocate data about quality more accurately, especially data concerning the

analysis itself but also including the lumpiness, humidity and contamination etc.

‐ Detailed melt and material cost calculation

Using the resources plan’s planning data for melt production (consisting of the

working plan and parts list for the standard recipe) and the consumption figures

booked on the cost collector for each material and/ or material orders, the material

and melt costs can be tracked precisely and are immediately available for cost

calculations.

Advantages and results

Planning and controlling melt operations are of key significance for the quality of casting and

for the cost effectiveness of the foundry itself. Being able to plan all the steps involved in

treatment, and being able to monitor the availability of materials and observe the status of

aggregates and ladles means planning can be much more reliable. Optimizing the use of

materials and the melt procedure reduces post-batching and melt costs and melt times can

be much shorter too. Seamlessly logging all the aspects of the melt process in every step of

the process, means the system guarantees traceability and provides complete

documentation at the touch of a button, for example in case there are any warranty claims by

customers.

Evaluating, recording and booking all the energy, alloy components and additives which are

used makes it possible for the controlling department to carry out reliable target/actual

comparisons for material costs. The potential savings which can be achieved during melt

operations - once IT-supported melt operations have been implemented - can be between 5

and 30% depending on the material. OPTI.melt can be deployed as an integrated MES

solution for

melt operations as a module within the comprehensive foundry ERP solution RGU OPTI or in

other already existing ERP systems.

99


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100


High Effective Linked Cylinder Head and Cylinder Block Production

in Double Castings at Volkswagen

Hocheffektive verkettete Zylinderkopf- und

Zylinderkurbelgehäusefertigung im Doppelkokillen-Kippguss bei

Volkswagen

Dr.-Ing. F. Hansen*, Dr.-Ing. R. Rösch, S. Uhde, K. Wagner, Volkswagen

AG, Leichtmetallgießerei Hannover, Hannover/Germany

The report presents the light metal foundry Hanover and the change to high-volume

production of cylinder heads and engine blocks in fully linked inorganic core production and

tilt casting.

The principle of inorganic core hardening and the inorganic compound forming binder

bridges are described.

A specific advantage of the inorganic binder system is the linked production with sequences:

deburring of cores by robots, optical contour inspection, automatic deposition on trays of a

conveyor belt, picking two complete core packages from the trays and placing them in the

permanent mould of the double casting machines without any core storage.

The two pons of the double casting machine are filled with molten Aluminum alloy from two

ladles, a double casting machine is tilted for 110° until both permanent moulds are filled with

melt. The casting sequence is 30 seconds per cylinder head.

The process and part quality of castings are optimized through inspection with a speedscan

computer tomography system on pores, shrinkages and inclusions. The result of this process

optimization is a reject rate for different product groups of internal 2 % and external 0,8%.

The summary emphasizes the advantage of inorganic core shooting technology combined

with standardized method of tilt casting and computer tomography inspection, which will be

used even in future for all cylinder head and engine block castings in our organization

section:

Komponente Casting of Volkswagen.

101


Graded Sands: Impact of Grain Size Distribution on Molding

Materials

Konfektionierte Sande: Einfluss der Kornverteilung auf

Formstoffparameter

Dr. H. Görke*, Dr. J. U. Zilles, M. Demary, Quarzwerke GmbH,

Frechen/Germany

The developments in foundry industry cause rising demands on the geometry and surface of

castings. Especially a high degree of automation and high production speeds as well as

challenging geometries require an optimized and constant quality of the processed materials.

The silica sand from Haltern is well known in foundry industry for its excellent properties in

grain shape and purity. However, its capability in terms of highly specialized applications is

still underestimated. Additionally to the standard grain sizes, the products can be filtered by

an industrial sieve stack and recombined into an ideal grain size distribution.

In the concrete and construction industry, modulating the packing density is an important

instrument to achieve special strength properties. By applying this context to foundry industry,

the complex interaction of involved parameters has to be considered. The optimization of one

parameter causes a change of several further parameters. For instance, a grain size

distribution to arrange a high packing density results into high bending strengths but exhibits

low gas permeability. Thus, the impact of the grain size distribution on numerous parameters

and its dependencies on each other were monitored by means of a program for statistical

analysis. For a better understanding of the underlying interactions, the amount of used cold-

box binder system was varied between 0.5 and 0.9%. The bending strength, gas

permeability, surface roughness, bulk density and flow behavior of the sand were detected

as responses. Several resulting correlations will be presented here. This dataset and the

possibility to recombine graded sieve fractions with high accuracy offer us an instrument to

produce improved grading curves unerringly.

102


Increase Your Casting Output, With 30% Higher Productivity on

DISA Vertical Machines

Steigern Sie Ihr Ausbringen mit 30 % höherer Produktivität auf vertikalen

DISA-Formanlagen

B. W. Haugbølle, DISA Industries A/S, Taastrup/Denmark

The presentation I make will focus on how to produce castings on DISAMATIC vertical

moulding machines, and will conclude which key parameters are important to focus on in

order to ensure stable high productivity, high quality castings with the improved yield.

Foundries are constantly seeking opportunities to improve casting quality, productivity and

savings at the same time. DISA have today developed a system that makes it possible to

increase casting quality, productivity and improved yield at the same time, compared to other

vertical moulding processes. One of the key points is to increase the available pouring time

on a high production vertical DISA line, DISA have new equipment available to help

customers to obtain more pouring time.

103


The presentation will cover two methods in how to increase the productivity on a vertical line.

A couple of customer cases will be presented, from customers that have been through a

conversion process.

Following points will be presented and explained:

How to increase productivity and available pouring time on a vertical machine.

How to increase casting quality and improve the yield

Case story from a customer who has obtained higher productivity.

Lower your cost per casting with DISA vertical moulding machines

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Climatic – A new and efficient approach for pollution Control of

BETX, Amines, and Tetraethyl Silicate at foundries

Gas phase advanced oxidation cleans industrial pollution

Abgasreinigungssystem zum Abbau von Luftschadstoffen in Abgasen

von Gießereien

Prof. Dr. P. Wiesen*, Bergische Universität Wuppertal,

Wuppertal/Germany; Prof. M. S. Johnson, C. Meusinger, University of

Copenhagen/Denmark; F. Hartung, M. Gallus, Infuser Deutschland

GmbH, Mannheim/Germany; N. Bork, K. Nannerup, T. Rosenørn, Infuser

ApS, Copenhagen, Denmark

Abstract

Gas Phase Advanced Oxidation (GPAO) is a new approach to air purification that is capable

of removing a broad range of pollutants including saturated and unsaturated hydrocarbons,

amines, particles, and ozone. Treatment occurs in the gas phase resulting in high energy

efficiency and low pressure drop. The treatment capacity can be scaled to match the load,

and systems have been designed and built over a broad range of flow rates, from 40 to over

40,000 m3/hour. Here we report on our latest results from test to remove amines, tetraethyl

silicates and benzene from foundry exhaust air.

1. Cleaning air like the atmosphere

GPAO is based on the self-cleaning mechanisms of Earth’s atmosphere: pollutants are first

oxidized into compounds of lower volatility and higher water solubility. In a second step these

compounds form aerosols that can be separated from the airstream using electrostatic

precipitators (Figure 3). GPAO was invented and developed by Professor Matthew S.

Johnson [1] at the Copenhagen Centre for Atmospheric Research, University of Copenhagen,

and is commercially available from INFUSER ApS under brand name CLIMATIC. GPAO has

been

tested in the laboratory and at a number of industrial sites.

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2. GPAO removes air pollution from foundries

Air pollution from foundries is diverse in composition and concentration. Compounds of

concern include carcinogenic benzene from binders used in the sand blocks that liquid metal

is cast in, tetraethyl silicate combustion products that clog downstream HVAC systems, and

amines due to their obnoxious smells. Common ways of pollution abatement include washers,

adsorption wheels, carbon filters and bio filters, which lead to higher costs.

Benzene removal was tested using a mobile installation consisting of a wet scrubber and

GPAO at a large German foundry in the Saar-region for several days. Benzene

concentrations were reduced by up to 90 % and the concentration of other hydrocarbons

were reduced by more than 80 %. The new technology proved to be able to treat benzene in

a controlled manner under the real conditions of a running foundry [2]. The pressure drop

through the system is much smaller compared to charcoal filters of the same benzene

removal efficiency.

Figure 3. Schematic of one design based on GPAO and a wet scrubber. Ozone is added in

the wet scrubber. This setup contains a two UV sections. ‘Growth’ boxes are empty and

provide volume and time for the chemical reaction and particle formation to occur. High

voltage (HV) is used to charge particles before the electrostatic precipitator (ESP). The

control function reads pollution loads at the inlet of the air cleaner and regulates the UV lamp

intensity to the needed amount.

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Recent tests in Mettmann, Germany were performed on exhaust air of a running foundry to

specifically test the performance of GPAO with respect to amine and tetraethyl silicate

removal. We will present preliminary results that show significant removal of tetraethyl silicate

and amines. Typical fluctuations in the flue gas of foundries point out another advantage of

GPAO compared to other, static air cleaners: the ability to adjust cleaning demand according

to pollution load. The operating costs of GPAO are largely driven by the power consumption

of the UV lamps, but these can easily be controlled (i.e. dimmed) according to detected inlet

concentrations. This principle is included in Figure 3. GPAO can also be designed as an up-

stream solution to reduce the running costs of existing filters in foundries.

[1] Johnson, M. S., Nilsson, E. J. K., Svensson, E. A., & Langer, S., Gas Phase Advanced

Oxidation for Effective, Efficient In Situ Control of Pollution, Environmental Science &

Technology (2014).

[2] Meusinger, C., Gasphasen-Emissionskontrolle fu�r Gießereien, Giesserei Praxis 4

(2014) 166.

107


Influence of Silicon Content, Strain Rate and Temperature on

Toughness of High Si Ferritic Ductile Cast Iron

Einfluss von Siliciumgehalt, Dehnrate und Temperatur auf die Zähigkeit

von ferritischem Gusseisen mit Kugelgraphit mit hohem Siliciumgehalt

T. Ikeda*, Dr. Eng. T. Umetani, N. Kai, Hinode, Ltd., Saga/Japan; Emer.

Prof. Dr. Eng. K. Ogi, Kyushu University, Fukuoka/Japan; Prof. Dr. Eng.

N-A. Noda, Dr. Eng. Y. Sano, Kyushu Institute of Technology,

Kitakyushu/Japan

Abstract

The purpose of this study was to elucidate the influence of silicon content (3~4%), strain rate

and temperature on the toughness of ferritic ductile cast iron. Using Charpy V-notch

specimens, three-point bending test was carried out in a range of strain rate, 10-2~103%/s, at

253K~295K. Absorbed energy were calculated by load-stroke curve on three-point bending

test. Ductile-brittle transition behaviors were analyzed in relation with silicon content, strain

rate and temperature.

1. Introduction

High Si ferritic ductile cast iron possesses the higher fatigue strength and a better

combination of strength and ductility compared with a similar strength level of traditional

ferrite-pearlite type ductile cast iron, indicating its potentialities for industrial applications. On

the contrary, Charpy impact test reveals that higher Si content raises the ductile-brittle

transition temperature, which hinders or restricts the application of this iron. However, as the

toughness of iron strongly depends on the strain rate as well as the temperature, we

investigated the influence of these factors on ferritic ductile cast iron containing 3.0~4.0%Si.

108


2. Experimental Procedure

Charpy V-notch specimens were machined from TypeⅡ Y-shaped (EN1563) 3.0~4.0%Si

ductile cast iron samples. And three-point bending tests were conducted in a range of

nominal strain

rate, 10-2~103%/s, at 253K~295K, using an electro-hydraulic servo testing machine. The

nominal strain rate was calculated by the equation, 6WQV/S2[1][2], where W = test

specimen width,

Q = plastic stress intensification factor(=1.94 in the case of V-notch) [1][2], V = stroke speed, S

= span length.

3. Results

As shown in Fig.1, at 295K, the absorbed energy (Et) of 3.7%Si and 4%Si iron started

dropping at the strain rate of 2.5×101%/s and 1.1×10-1%/s, respectively. The brittle fracture

surface appeared above these critical strain rates. At 253K, the ductile to brittle transition

occurred at 2.0×102%/s and 1.1%/s for 3.0%Si and 3.3%Si iron, respectively. The 3.7%Si

and 4.0%Si specimens showed brittle fracture at any strain rate. As the higher strain rate and

the lower temperature gave similar effects on the toughness of iron, the absorbed energy

was expressed in relation to a strain rate-temperature parameter R as shown in Fig.2(a). R =

T ln(A/ ), where T = temperature, A = 108 [2],[3], = nominal strain rate. The critical R value for

ductile to brittle transition (Rs) decreased linearly with decreasing the Si content as depicted

in Fig.2 (b).

Fig.1: Influence of strain rate on the

absorbed energy of 3.0~4.0%Si ductile

cast iron at 295K and 253K.

109


Fig.2: Ductile-brittle transition behavior

illustrated in relation to strain

rate-temperature parameter.

REFERENCES

[1] R.Sandstrom, Y.Bergstrom: "Rerationship between Charpy V transition temperature in

mild steel and various material parameters", Met. Sci., 18(1984),177-186

[2] H. Yamamoto, T. Kobayashi, H. Fujita: "Strain Rate Dependency of Ductile-Brittle

Transition Behavior in Ductile Cast Iron ", JOURNAL OF JAPAN FOUNDRY

ENGINEERING SOCIETY 72(2000), 107-112

[3] P.E.Bennett, G.M.Snclair: "Parameter Representation of Low-Temperature Yield

Behavior of Body-Centered Cubic Transition Metals", ASME paper, 65-MET-11(1966),

518-524

110


Automated Quality Control for Tools, Patterns and Cast Metal Parts

with Optical 3D Metrology Systems

Automatisierte Qualitätssicherung von Werkzeugen, Modellen und

Gussteilen durch optische 3D-Messsysteme

S. Adolf, GOM Gesellschaft für Optische Messtechnik mbH,

Braunschweig/Germany

3D Shape & Dimension Measurements and Online Tracking

Optical 3D measuring systems such as fringe projection systems and laser scanners have

become firmly established alongside tactile measuring machines as industrial production

measuring technology for complete, full-surface measurement of component geometry.

Optical 3D coordinate measuring acquires the entire component geometry in a dense point

cloud instead of measuring individual points only. The measured data obtained can be used

in areas as inspection, reverse engineering, in pattern, tool and mold making, in engineering

and machining (CAD/CAM), during first article inspection, in production related quality

assurance (CAQ) and in process control (PCS).

Worldwide, optical 3D measurement technology is used as a precise, fast and robust

measuring solution in pressure die, gravity die and sand casting as well as in lost foam and

investment casting processes. Due to its high quality measurement data and flexibility,

optical measuring technology is implemented in measuring rooms as well as in production

related quality control. Enhanced functions enable online part tracking for core assembly and

for alignment on CNC machine pallets including allowance control. In addition, the back

projection function of lines and points by the 3D sensor makes the use of conventional

marking plates for cast blanks no longer necessary.

111


Automated 3D Measuring Technology

This presentation describes the functions and practical applications for full-field optical 3D

metrology: geometrical 3D measurements for shape & dimension measurement and

inspection on wax patterns, pattern plates, ceramic cores, sand cores, moulds, dies and cast

parts with a focus on automated quality control. In industrial production, automated

measurement cells achieve higher throughput rates (higher unit volumes in a shorter time

and with improved predictability), plus improved reproducibility (process reliability). The key

to automated measuring processes is a parametric measurement software approach, which

enables exact planning of measuring cells with all their components and kinematics (virtual

measuring room). The parametric software opens the way for standardized and centralized

component inspection with traceable quality control processes.

Optical metrology produces absolute measurement results, thus guaranteeing reliable

analyses that are available in a very short time. The visualization of the measurement results

is supported by the geometry data (CAD) which allows an easy and quick understanding of

the measurement reports.

ATOS Triple Scan for quality control of complex cast parts, automated in the ATOS ScanBox

112


Defective Castings Detection in Large Ductile Iron Production Using

a Machine Learning Approach

Ausschussdetektion bei Großguss aus Gusseisen mit Kugelgraphit mit

selbstlernenden Algorithmen

Dr.-Ing. G. Bertuzzi, SACMI Imola S.C., Imola (BO), Italy

Abstract

The FD-kNN method has been applied to large ductile iron production to support the

standard quality control in finding defective castings. In the verification case, using data from

standard production, the method accuracy reached 90%.

1. Introduction

The foundry process is usually controlled using statistical methods. Although they detect

excessive process variations, some defective items might be misclassified as sound, due to

the strongly non linearity and great amount of interacting process variables [1]. To overcome

this issue, some foundries introduced Machine Learning methods to support process control

[2-3]. The main limitation is they need both sound and defective items as samples to train the

method. In heavy section ductile iron production, due to the casting’s dimensions, only critical

area are checked and defects in other area can be found out only if there would be a

catastrophic failure. In other industries similar problems have been solved using a new

machine learning approach called Fault Detection k-Nearest Neighbour (FD-kNN) [4-5]. This

method can detect defective item during the production step comparing the process

parameters with a training set made only of sound items. In this study the same method has

been applied to three batches from different suppliers of large ductile iron castings (more

than 30 tons) with sound (S) and defective (D) items.

113


2. Method

The FD-kNN method has been applied to large ductile iron castings. The dataset is made of

142 items (127 S and 15 D) from 3 different suppliers. For each item the process parameters

regarding chemistry, sand and pouring have been recorded. The data have been processed

with the method described in [4] and represented in Picture 1. The training dataset was set

using 12 items (the first 4 items from each suppliers’ batch). These items were fully

acceptable to the standard quality control and haven’t shown any issue during several

working years. The remaining 130 items (115 S and 15 D) have been used in the Fault

Detection Part (b) to validate the model.

3. Discussion

Picture 2 shows the results of the validation where the method accuracy have been

evaluated by measuring False Negative Rate, FNR = FN/(FN+TP) where TP is the number of

defective castings correctly classified (True Positive) and FN the number of faulty castings

misclassified as valid (False Negative), and False Positive Rate,FPR= FP/(FP+TN), where

FP is the number of valid casting incorrectly detected as defective (False Positive) and TN

the number of sound castings correctly classified (True Negative). For this case study we got

FN=1, TP=14, FP=12 and TN=103, so the FNR and FPR are respectively 6.7% and 10.5%.

The Accuracy, A= (TP+TN)/(TP+FP+TN+FN) is 90%.

Picture 1: Flow Diagram showing the Model

Building and the Fault Detection from [4].

114


Picture 2: Chart showing the results

of the validation step

4. Conclusion

It has been shown that it’s possible to apply FD-kNN method to large ductile iron production

achieving accuracy of 90%. This method can support the standard quality control to be more

effective and efficient,and suppliers can understand better which process parameters are

more relevant and how they interact between them in a defective castings. In the future tools

to weight the importance of each parameters should be introduced in the method to mark

better the distance between sound and defective items.

[1] Zabala A., Suárez R., Maguregi J.: “Advanced prediction tools, foundry process control

and knowledge management for iron castings”, in Proceedings of 68th WFC, 2008;

[2] Santos I., Nieves J., Penya Y.K., Bringas P.G.: “Optimising machine-learning based

fault prediction in foundry production”, in Proceedings of the 2nd International

Symposium on Distributed Computing and Artificial Intelligence (DCAI), 2009;

[3] Nieves J., Santos I., Penya Y.K., Brezo F., Bringas P.G.: “Enhanced foundry production

control” in Proceedings of the 21st International Conference on Database and Expert

Systems Applications (DEXA), 2010;

[4] He Q.P., Wang J.: “Fault detection using the k-nearest neighbor rule for semiconductor

manufacturing processes” in Semiconductor manufacturing, IEEE transactions, 2007;

[5] He Q.P., Wang J.: "Principal component based k-nearest-neighbor rule for

semiconductor process fault detection" in American Control Conference, 2008.

115


Thread New Paths in Automated Defect Recognition (ADR) for

Castings

Faster – More Accurate – Reduced Set-Up Time – Less Costs

Neue Wege in der automatischen Fehlererkennung an Gußteilen.

Schneller – Genauer – Kaum Rüstzeit – Geringere Kosten

H. Schulenburg, VisiConsult GmbH, Stockelsdorf/Germany

Nowadays, a great number of safety-relevant parts in the automotive and aviation industry

are casted. In general, all these parts must be X-rayed. Normally, X-raying is done in fully

automatic X-ray cells. Fully automatic means that no operator intervention is required from

loading, testing and unloading. In each testing position, the integrated intelligent image

interpretation is searching for cavities and/or inclusions and compares them with the relevant

quality standard.

So far so good -> that’s state-of-the-art

What does automatic image interpretation need for providing exact results and yet

minimising erroneous rejects?

‐ Source of radiation

‐ Image sensor (flat panel detector)

‐ Part manipulator and/or manipulator for imaging

Automatic image interpretation is always well functioning if the parts are always positioned in

the same way in the course of beam so that a reference image can be taken. During the

running testing process the new part is inserted such that the taken image looks like the

reference image.

Unfortunately, this is quite a theoretical situation.

116


There are several variances affecting the positioning accuracy:

E.g.: - Part is modified (burr, modified form)

- Part is not well positioned on the holder

- Part holder is worn out or shifted

Great effort is needed to reach and to maintain this machine status, e.g. grippers or part

holders must be replaced regularly. If different pallets are used, these must be aligned to

each other which is very complex.

We contemplated how to improve this situation.

The idea is quite simple and works in principle as follows:

‐ Parts are lying on simple holders, e.g. radiation-permeable plastic boards

‐ A 3D measuring system identifies the position of the part

‐ The position is transmitted to a supervisory system

‐ The supervisory system controls a robot carrying the imaging system

‐ The position of the imaging system is then always approached referred to the virtual

zero of the part, thus reaching high-precision positioning of the part

The benefits of the system are clear:

‐ No costs for complex part holders or grippers

‐ Wear is always automatically compensated for

‐ Easy part change – no changeover time

‐ New parts can be adapted quickly – thus suitable for small batches series

‐ System can be rented as it is suitable for any kind of parts

This patented system is called XRH RobotStar. Get more information at our booth 11H08 or

under visiconsult.com

118

Dienstag/Tuesday, 16.06.2015 Bis/Till Freitag/Friday, 19.06.2015

List of Speakers in Alphabetical Order

Referentenliste in alphabetischer Reihenfolge

Adolf, S. GOM, Braunschweig, Germany

Archibald, J., ASK-Chemicals, Dublin Ohio, USA

Bembenek, K., RGU GmbH, Dortmund, Germany

Bertuzzi, G., Dr.-Ing., SACMI, Imola, Italia

Bramann, H., Dr.-Ing., MAGMA Gießereitechnologie GmbH, Aachen, Germany

Brieger, G., Chemex GmbH, Delligsen, Germany

Child, N., Foseco International Limited, Tamwort, /United Kingdom

Decking, K., Georg Fischer Automotive AG, Schaffhausen, Switzerland

Dieckhues, G.W., Dr.-Ing., Ohm & Häner Metallwerk GmbH & Co. KG, Olpe,

Germany

Dinglreiter, U. Dr., R- Scheuchl G,bH, Ortenburg, Germany

Doppler, H., Managementberatung Doppler, Freiberg am Neckar, Germany

Feikus, F. J., Dr.-Ing., Nemak Europe GmbH, Frankfurt am Main, Germany

Fesch, J., Sakthi Portugal Group SA

Görke, H., Dr., Quarzwerke GmbH, Frechen, Germany

Greven, K., Dr. rer. Nat., KSM Castings Group GmbH, Hildesheim, Germany

Gundlach, J., Dr., Grunewald GmbH & Co KG, Bocholt, Germany

Hansen, F., Dr.-Ing., Volkswagen AG, Leichtmetallgießerei, Hannover, Germany

Haugbølle, B.W., DISA Industries A/S, Taastrup, Denmark

Ikeda, T., HINODE Ltd., Tokio, Japan

Joachim, C., Hüttenes-Albertus Chem. Werke GmbH, Düsseldorf, Germany

Kohlmeyer, P., G.A. Röders GmbH & Co. KG, Soltau, Germany

Löken, I., Spaleck Oberflächentechnik GmbH & Co. KG, Bocholt, Germany

Mülleder, C., CTP Chemisch-Thermische Prozesstechnik GmbH, Graz, Austria

Mueller, T., Voxeljet of America Inc., Canton, USA

Murrel, P., Dr., Cast Metals Federation, Birminham, United Kingdom

119


List of Speakers in Alphabetical Order

Referentenliste in alphabetischer Reihenfolge

Oberdorfer, B., Dr., ÖGI, Leoben, Austria

Officer, B., Amcol Metalcasting

Pirovano, R., Flow Science Inc., Santa Fe, USA

Prat, J., ASK Chemicals España, Castro Urdiales, Spain

Reichen, P., Dr., Bühler AG, Uzwil/Switzerland

Richardson, N., S & B, United Kingdom

Rische, M., Dr.-Ing., ABP Induction Sysetms GmbH, Dortmund/Germany

Sakai, T., SINTOKOGIO Ltd., Toyokawa/Japan

Schrey, A., Dr.-Ing., Foseco Europe Marketing & Techology, Borken, Germany

Schulenburg, H., VisiConsult GmbH, Stockelsdorf, Germany

Sobota, A., Dr.-Ing., Eisenwerk Brühl GmbH, Brühl, Germany

Tagg, A., John Winter, Geopola

Tappan, R., Texmaco Rail, Kolkata, India

Todte, M., Dr.-Ing., Flow Science Deutschland GmbH, Rottenburg, Germany

Tomazic, D, Chem-Trend (Deutschland) GmbH, Gernlinden, Germany

Trikha, S., Hüttenes Albertus

Trinowski, D., Hüttenes-Albertus Chem. Werke GmbH

Wiesen, P., Prof. Dr., Bergische Universität Wuppertal, Wuppertal, Germany

Wilding, C., Omega Foundry Machinery Ltd., Peterborough, United Kingdom

120


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