College of Engineering

Mechanical Engineering Department

Prepared by:

Team Members:

1- Fahad Mohammed Alshahrani

2- Mohammed Abdo Moukley

3- Abdul Rahman Hassan Jed

4- Hayaf Menahi Alshahrani

5- Abdullah Mohammed Abu Alsummah

PROJECT ADVISOR :

Ass. Prof. Dr. Osama Mohamed Hussein Ibrahim

A Senior Project report submitted in partial fulfillment

of the requirement for the degree of BACHELOR OF Science (B.Sc.),

In

Mechanical Engineering

(Completion Date 7 / 1435)

كلية اليندسة

قسن اليندسة الويكانيكية

طريقة عن عوليات السباكة الرهلية

التصوين للنواذج و الوصبات و الدالليك و

نظام هجارى الصب لسبائك هن األلوهنيوم

فيد هحود الشيرانى- 1طالب فريق العول

هحود عثده هٌكلى- 2

عثد الرحون حسن جد - 3

ىياف هناحى الشيرانى- 4

عثد هللا هحود اتٌ الصوو - 5

هشرف الوشرًع

أساهو هحود حسين اتراىين\ استاذ هساعد دكتٌر

ستقرير مشروع التخرج مقذم للحصىل على درجة البكالىريى

فى الهنذسة الميكانيكية

لجنة التحكين

(هشرف) حسين هحود اساهة/د

ناصر سرًر عدلى/ د

عثد الناصر هحود الشعيثى/د

(1435 / رجة )تاريخ التقدم

College of Engineering Jazan University

APPROVAL RECOMMENDED:

Examination Committee :

1- Dr. Osama Mohamed Hussein Ibrahim.

2- Dr. Naser Adly Mostafa Sorour.

3- Dr. Abd Al-Nasr Mohamed Al-Shuaabi.

PROJECT ADVISOR

Ass. Prof. Dr. Osama Mohamed Hussein Ibrahim

Date :13/7/1435H

______________________________

DEPARTMENT HEAD

____________________________

DATE

______________________________

COURSE INSTRUCTOR

______________________________

DATE

APPROVED: ____________________________________________________

DEAN, COLLEGE OF ENGINEERING ____________________________________

DATE

ABSTRACT

Senior project submitted to the department of (Mechanical) Engineering

The art of foundry (casting processes) is one of the earliest metal shaping methods known to

human being. It can be used for very complicated geometrical shape, large size components

(several tones). It is, also, economically visible for one component to several thousand

components. The sand casting is the most widely used type of casting processes.

Through the present project work commercial aluminum alloy with copper, nickel and

magnesium called Y-alloy was cast in sand mold successfully. An aluminum 4 engine piston

of TOYOTA was produced in good quality without any defects. The AutoCAD used in the

present work to produce the 3D model of the casting object, so the different allowance can be

added graphically to this 3D model. As a result the volume of the casting, after adding the

different allowance, can be obtained to complete the design of the gating system. The reverse

engineering design was used to prepare the pattern of casting mold. The pouring sprue, riser,

gating system were designed for sand.

In this project the fitting and machining operations for the final dimensions of making

product have been done. Cost evaluation of selected product was done compared with original

product. However, production of 478 pieces per month gives the breakeven point [costs (fixed

and variable) equal sale value] and then begins the profit by increasing the production.

iv

DEDICATION

To my Father and all member of family, who, through his financial and moral

support was the source of inspiration and the mainstay in my attaining an education, I

dedicate this project.

v

ACKNOWLEDGEMENT

This project was written under the direction and supervision of Dr.\ Osama Mohamed

Hussein Ibrahim, the Assistance Professor at Mechanical Department, Faculty of

Engineering, Jazan University. We would like also to express our sincere appreciation to

him for the interest and assistance given to us. We are indebted for his guidance, frequent

helpful discussion, fruitful advices and assistance during the present work.

TABLE OF CONTENTS

vi

PAGE

ABSTRACT……………………………………………………….. iv

DEDICATION…………………………………………………….. v

ACKNOWLEDGEMENT………………………………………… vi

LIST OF FIGURES ……………………………………………… viii

LISTOFTABLES…………………………………..…………….… ix

NOMENCLATURE (Optional)………………..……………..….. x

CHAPTER 1

INTRODUCTION ………………………………………..………… ……….. 1

CHAPTER 2

LITERATURE REVIEW …………………………….……………………… 4

1.2 Problem Statement Objective ……………….…. 23

1-3 Problem justification and Outcomes …………… 25

1-4 Problem Constraints………………………………… 25

CHAPTER 3

EXPERIMENTAL PROCEDURES ……………………………… 26

3-1 Mathematical models and formulations…………… 31

CHAPTER 4

RESULTS AND DISCUSSION………………………….………… 32

CHAPTER 5

FEASIBIILITY STUDIES AND MARKET NEEDS………………. 34

CHAPTER 6

CONCLUSION AND RECOMMENDATIONS …………………… 36

vii

1. APPENDIXES

1.5”

A: Project Team with assigned responsibilities. ……..…… 37

B: Faculty Advisers and Industry sponsors …………..…… 37

C: Project Budget and Expenses to date ………….. ……. 37

D: Drawing package (if applicable). ……..…………… 37

D-1 : Orginal product ……………………….. 38

D-2: Design of pattern ……………………….. 39

D-3 :1st Sand Mold (Base of Piston) …………… 40

D-4 :2nd

Sand mold (Body of Piston ) …………. 40

D-5 :3rd

Sand Mold (Sprue) …………………………. 41

D-6: Assembly after cleaning…………………… 41

D-7:Making product after casting ………………… 42

E: Manufacturing procedures, Test procedures and

Test reports…………………………………………… 42

F: Technical reports or evaluations ………………….. 43

G: All subjects that have been applied in our project... 43

REFERENCES……………………………………….. 42

BIBLIOGRAPHY……………………………………….. 43

LIST OF FIGURES

vii

FIGURE No DESCRIPTION PAGE

(Fig. 2.1) Phase diagram of aluminum silicon alloy. 4

(Fig. 2.2) Classification of Solidification. 8

(Fig. 2.3) Schematic illustration of a sand mold features. 10

(Fig. 2.4) Flowchart of Steps in Sand Casting. 10

(Fig. 2.5) Typical Gating system . 11

(Fig. 2.6) sprue base well design. 12

(Fig. 2.7) Casting defects. 13

(Fig. 2.8) Hot –Chamber Die Casting 13

(Fig. 2.9) Cold – Chamber Die Casting 13

(Fig. 2.10) Design change to eliminate the need for using a core

(a) Original design , and (b) redesign 21

(Fig. 3.1) Sand mixture of water and clay. 26

(Fig. 3.2) Casting processes. 27

(Fig. 3.3) Melting and pouring process 28

(Fig. 3.4) Product after casting. 28

(Fig. 3.5) Machining Processes 29

(Fig. 4.1) Sprue and gating and system design 33

(Fig. 5.1) The relationship between the cost and revenue values 35

(Break Even Point).

LIST OF TABLES

viii

TABLE No DESCRIPTION PAGE

(Table 1.1) Typical products made from aluminum sand 3

casting alloys.

(Table 2.1) Pattern shrinkage allowance. 8

(Table 2.2) Some grade designation and composition of 16

aluminum casting alloys.

(Table 2.3) Typical (and minimum) tensile properties of 19

aluminum casting alloys.

(Table 2.4) Factors affecting selection of casting process 22

for aluminum alloys

(Table 3.1) Effeciency coffecient for various types of gating

System. 31

NOMENCLATURE

Symbols DESCRIPTION UNITS

a acceleration m2/s

ix

g gravity acceleration m2/s

P Pressure Pa

ΔTo freezing range of alloy (TL - TS) 0C

cm centimeter cm

g, gm gram gm

m meter m

mg milligram mg

ml, ML milliliter ml, ML

TAC treatment of aluminum in crucible 0C

UTSltimate tensile strength(newton\ millimeter squar) N\mm2

v volume mm3

min minimum; minute min

mph miles per hour mph

M metal M

MPa Mega Pascal MPa

OD outside diameter mm

kg kilogramkg

km kilometer km

kPa kilopascal kPa

ksi kips (1000 lb) per square inch ksi

lb pound lb

L liquid; liter L

P pressure; particle Pa

r particle radius; radius of any particle with no irregularities mm

s second s

t time; thickness s

g/cm3 density g/cm3

T temperature; cooling rate

Tf equilibrium temperature; furnace temperature

Tm melting temperature 0C

μ micron μ

μg microgram μg

μm micrometer μm

psia pounds per square inch absolute psia

L length; latent heat per unit volume

STP standard temperature and pressure

LF ladle furnace

Ref reference

S solid

R gas constant; growth rate; radius; gas constant

atm atmosphere

CHAPTER I

INTRODUCTION

x

Sand casting, which in a general sense involves the forming of a casting mold with sand,

includes conventional sand casting and evaporative pattern (lost-foam) casting. This section

focuses on conventional sand casting, which uses bonded sand molds. In conventional sand

casting, the mold is formed around a pattern by ramming sand, mixed with the proper bonding

agent, onto the pattern. Then the pattern is removed, leaving a cavity in the shape of the

casting to be made. If the casting is to have internal cavities or undercuts, sand cores are used

to make them. Molten metal is poured into the mold, and after it has solidified the mold is

broken to remove the casting. In making molds and cores, various agents can be used for

bonding the sand. The agent most often used is a mixture of clay and water. (Sand bonded

with clay and water is called green sand). Sand bonded with oils or resins, which is very

strong after baking, is used mostly for cores. Water glass (sodium silicate) hardened with CO2

is used extensively as a bonding agent for both molds and cores.

The main advantages of sand casting are versatility (a wide variety of alloys, shapes, and

sizes can be sand cast) and low-cost of minimum equipment when a small number of castings

is to be made. Among its disadvantages are low dimensional accuracy and poor surface finish;

basic linear tolerances of ±30 mm/m (±0.030 in./in.) and surface finishes of 7 to 13 μm, or 250

to 500 μm, as well as low strength as a result of slow cooling, are typical for aluminum sand

castings. Use of dry sands bonded with resins or water glass results in better surface finishes

and dimensional accuracy, but with a corresponding decrease in cooling rate.

Casting quality is determined to a large extent by foundry technique. Proper metal-

handling and gating practice is necessary for obtaining sound castings. Complex castings with

varying wall thickness will be sound only if proper techniques are used. A minimum wall

thickness of 4 mm (0.15 in.) normally is required for aluminum sand castings.

Aluminum, the second most plentiful metallic element on earth, became an economic

competitor in engineering applications as recently as the end of the 19th century. It was to

become a metal for its time. The emergence of three important industrial developments

would, by demanding material characteristics consistent with the unique qualities of

aluminum and its alloys, greatly benefit growth in the production and use of the new metal

few decades the Wright brothers gave birth to an entirely new industry which grew in

1

partnership with the aluminum industry development of structurally reliable, strong, and

fracture-resistant parts for airframes, engines, and ultimately, for missile bodies, fuel cells,

and satellite components. The aluminum industry's growth was not limited to these

developments. The first commercial applications of aluminum were novelty items such as

mirror frames, house numbers, and serving trays. Cooking utensils were also a major early

market. In time, aluminum grew in diversity of applications to the extent that virtually every

aspect of modern life would be directly or indirectly affected by its use.

Aluminum has a density of only 2.7 g/cm3, approximately one-third as much as steel (7.83

g/cm3), copper (8.93 g/cm3), or brass (8.53 g/cm3). It can display excellent corrosion

resistance in most environments, including atmosphere, water (including salt water),

petrochemicals, and many chemical systems. The major impurities of smelted aluminum are

iron and silicon, but zinc, gallium, titanium, and vanadium are typically present as minor

contaminants. Internationally, minimum aluminum purity is the primary criterion for defining

composition and value. In the United States, a convention for considering the relative

concentrations of iron and silicon as the more important criteria has evolved. Aluminum alloy

castings are routinely produced by pressure-die, permanent-mold, green- and dry-sand,

investment, and plaster casting.. Process variations include vacuum, low-pressure, centrifugal,

and pattern-related processes such as lost foam. Castings are produced by filling molds with

molten aluminum and are used for products with intricate contours and hollow or cored areas.

The choice of castings over other product forms is often based on net shape considerations.

Reinforcing ribs, internal passageways, and complex design features, which would be costly

to machine in a part made from a wrought product, can often be cast by appropriate pattern

and mold or die design. Premium engineered castings display extreme integrity, close

dimensional tolerances, and consistently controlled mechanical properties in the upper range

of existing high-strength capabilities for selected alloys and tempers.

Generally considered of aluminum alloys to be very cartable and Pouring temperatures

low due to low melting temperature of 660C (1220F). Their properties are light

weight, range of strength properties by heat treatment and easy to machine.

Typical products (cf. table 1.1) made from some common aluminum sand casting alloys

include:

2

Table 1.1 Typical products made from aluminum sand casting alloys.

Other aluminum alloys commonly used for sand castings include 319.0, 355.0, 356.0, 514.0,

and 535.0.

The aim of this project is production by sand casting as a result the volume of the casting,

after adding the different allowance, can be obtained to complete the design of the gating

system. The reverse engineering design was used to prepare the pattern of casting mold.

3

CHAPTER 2

LITERATURE REVIEW

2.1 Overview

A Foundry is a casting factory which equipped for making molds, melting and

handling molten metal, performing the casting process, and cleaning the

finished casting.

2.1.1 Phase Diagram (cf. figure 2.1)

2.1.2 Pouring

It is critically important that the metal be drawn and poured according to the best manual

or automatic procedures. These procedures avoid excessive turbulence, minimize oxide

generation and entrainment, and limit regassing of hydrogen. Frequent skimming of the melt

surface from which metal is drawn may be necessary to minimize oxide contamination in the

ladle. Siphon ladles that fill from below the melt surface are used for these purposes, but most

often, coated and preheated ladles of simple design are employed. The process of repetitive

drawing and skimming inevitably degrades melt quality, and this necessitates reprocessing if

required melt quality limits are exceeded.

4

Pouring should take place at the lowest position possible relative to the pouring basin

Fig. 2.1 Phase diagram of aluminum silicon alloy. Fig. 2.1 Phase diagram of aluminum silicon alloy.

or sprue opening. Once pouring is initiated, the sprue must be continuously filled to minimize

aspiration and to maintain the integrity of flow in gates and runners. Counter-gravity mold

filling methods inherently overcome most of the disadvantages of manual pouring. Proprietary

casting processes based on low pressure, displacement, or pumping mechanisms might be

considered optimum for preserving the processed quality of the melt through mold filling, but

some important and relevant considerations apply. Melt processing by fluxing is more

difficult in some cases because the crucible or metal source may be confined. If, as in the case

of low-pressure casting, the passage for introducing metal into the mold is used repetitively,

its inner surface becomes oxide contaminated and a source of casting inclusions. In other

counter-gravity casting, mold intrusion into the melt and devices employed to displace or

pump metal to the cavity may be the source of turbulence, moisture reactions, and the

possibility of hydrogen regassing. Automated pouring systems are common in the die casting

industry. Robotized ladle transfer, as well as metered pumping, may nevertheless incorporate

features and reflect provisions to protect molten metal quality through sound drawing,

transfer, and pouring techniques. The same techniques have application in die casting

operations in which these operations are performed manually. Hot chamber operation offers

apparent metal transfer advantages over cold chamber operation. Recent developments in the

use of siphons or vacuum legs to the cold chamber in pressure die casting offer new and

interesting opportunities for upgrading the quality of the metal deliverable to the die cavity.

2.1.3 Gating and Riser

It is beyond the scope of this article to discuss comprehensively the subject of gating and

riser for the processes employed in the casting of aluminum. In fact, it is in the practices,

methods, and designs of gating and riser that individual foundries most differentiate their

capabilities. For the most part, the evolution of these systems has been based on experience,

and effective and imaginative solutions incorporating refined fluid and solidification

dynamics have been developed. More recently, technical societies and associations have

fostered and developed sophisticated techniques for the design of gates, runners, and risers in

gravity casting and for the design of gates, runners, models, and analytical control schemes for

pressure die casting. There is general agreement on the principles applicable to this highly

individualistic and vital phase of metal casting.

5

Ultimately, the challenge to the foundryman is the transfer of metal at the desired quality level

to the casting cavity while retaining an acceptable level of metal quality through transfer and

ensuring that solidification occurs in such a way that an acceptable level of surface,

dimensional, and internal quality is attained. Transfer initiates with drawing and/or pouring,

and it concludes with the final compensation of volumetric shrinkage by the riser system.

The methods for introducing metal into the casting cavity, for minimizing degradation in

metal quality, and for minimizing the occurrence of shrinkage porosity in the solidifying

casting differ among the various casting processes, primarily as a function of process

limitations. However, the objectives and principles of gating and riser are universally

applicable:

- Establish no turbulent metal flow.

- Systematically fill the mold cavity with metal of minimally degraded quality.

- In conjunction with the selection of an appropriate pouring temperature, provide conditions

for mold filling consistent with mistune avoidance.

- Establish thermal gradients within the cavity to promote directional solidification and to

enhance riser effectiveness.

- Design riser size and geometry, and locate risers and riser inlets to minimize the ratio of

gross weight to net weight.

- Minimize to the extent possible the vertical distance the metal must travel from the lowest

position of metal entry to the base of the sprue

- Taper the sprue or use sprue geometry other than cylindrical to minimize overtaxing and

aspiration.

- Keep the sprue continuously filled during pouring.

- Avoid abrupt changes in the direction of metal flow; gate and runner passages should be

streamlined for minimum induced turbulence at angles or points of divergence in the system.

- Provide contoured transitions in gate, runner, and infeed cross sections at points of cross-

sectional area changes.

- Employ multiple gates to improve thermal distribution and to reduce metal velocity at entry

points.

- Avoid molten metal impingement on mold surfaces or cores by appropriate gate

location.

- Design runners and gates, if two or more sprues are used, to prevent the turbulence

associated with the collision of flow patterns.

6

- Design risers to be of sufficient size and effectiveness to compensate for volumetric

shrinkage. Riser position, shape, and filling from the gating system relative to the

casting cavity are interrelated and critical considerations. In general, risers should be

placed to achieve the maximum pressure differential and, when possible, should be

open to the mold surface. Blind or enclosed risers must be adequately vented.

- Observe the principles of directional solidification. The use of chills, riser insulation,

and casting design changes may be required. The effects of inadequate gating and riser

design can in some cases be corrected only by complete redesign.

- Provide runner overruns, dross traps, or in-system filtration to avoid the impact of

degraded metal on casting quality.

- Locate the runners in the drag and locate the gates in the cope for horizontal mold

orientation. This rule is subject to intelligent variation by the uniqueness of each part

- Place the riser cavities in the gate path for maximum effectiveness whenever possible.

- Never place filters (if used) between riser and cavity.

- Design the gates so that metal entry occurs near the lowest surface of the casting

cavity.

- Geometrically contour the runners to maintain uniform fluid pressure throughout

formulas applicable to all gravity casting methods have been developed for this

purpose.

- Consider the ease and economics of trimming operations in gate and riser design.

Somewhat different techniques in gating and riser are used for different alloys. In

general, riser size and the need for stronger thermal gradients increase with more

difficult-to-cast alloys. Crack sensitivity or hot shortness forces compromises in the

steps normally taken to achieve directional solidification. Extensive localized chilling

may aggravate crack formation. In these cases, more uniform casting section thickness,

larger fillets, more gradual section thickness changes, larger risers and in some cases

riser insulation, and more graduated chilling offer the best prospects for success. In

alloys that are more difficult to feed but are relatively insensitive to cracking at

elevated temperature, establishing thermal gradients by selective chilling (and heating

as in permanent mold casting) usually provides good casting.

2.1.4 Solidification and Shrinkage

Solidification: It has been shown that fluidity is inversely proportional to freezing range

7

(that is, fluidity is highest for pure metals and eutectics and lowest for solid-solution alloys).

The manner in which solidification occurs may also influence fluidity (cf. figure 2.2).

Shrinkage: For most metals, the transformation from the liquid to the solid state is

accompanied by a decrease in volume. In aluminum alloys, volumetric solidification

shrinkage can range from 3.5 to 8.5%. The tendency for formation of shrinkage porosity is

related to both the liquid/solid volume fraction and the solidification temperature range of the

alloy. Riser requirements relative to the casting weight can be expected to increase with

increasing solidification temperature range (cf. table 2.1).

Table 2.1 Pattern shrinkage allowance.

2.2 Metal Casting Processes

* Two main categories:

8

A. Expendable mold processes –A mold after process must be destroyed in order to

Metal

Volume Contraction

Solidification Thermal Contraction

Aluminum 7% 5.6%

Al alloys 7% 5%

Gray Cast Iron 1.8

3

Gray cast iron with High C

0 3

Low C Cast Steel 3

7.2

Copper 4.5

7.5

Bronze 5.5

6

Fig. 2.2 Classification of Solidification.

remove casting:

– Mold materials: sand, plaster and similar materials +binders

– More intricate geometries

B. Permanent mold processes – A mold can be used many times to produce many

Castings:

– Mold: made of metal and, less commonly, a ceramic refractory material.

– Part shapes are limited

– Permanent mold processes are more economic in high production operations.

2.2.1 Sand Casting

• Most widely used casting process. • Parts ranging in size from small to very large

• Production quantities from one to millions.

• Basic features of Molds (cf. figure 2.3)

– Mold: cope (upper half) & drag (bottom half).

– Flask – containment.

– Parting line.

– Pattern – the mold cavity.

– The gating system – pouring cup, (down) sprue, runner.

– Riser: a source of liquid metal to compensate for shrinkage during solidification.

• Sand Molds

– Typical Sand with mixture: 90% sand, 3% water, and 7% clay.

– To enhance strength and/or permeability.

– Refractory for high temperature.

– Size and shape of sand:– Small grain size -> better surface finish.

– Large grain size -> to allow escape of gases during pouring.

– Irregular grain shapes -> strengthen molds but to reduce permeability.

• Types:

– Green-sand molds - mixture of sand, clay, and water; “Green" means mold

contains moisture at time of pouring.

– Dry-sand mold - organic binders rather than clay are baked to improve strength.

9

2.2.1.1 Steps in Sand Casting (cf. figure 2.4)

The cavity in the sand mold is formed by packing sand around a pattern, separating

the mold into two halves:

– The mold must also contain gating and riser system.

– For internal cavity, a core must be included in mold.

– A new sand mold must be made for each part.

1. Pour molten metal into sand mold.

2. Allow metal to solidify.

3. Break up the mold to remove casting.

4. Clean and inspect casting.

5. Heat treatment is sometimes required to improve metallurgical properties.

2.2.1.2 Casting Processes

• Forming the Mold Cavity:

– Mold cavity is formed by packing sand around a pattern.

– The pattern usually oversized for shrinkage is removed.

10

– Sand for the mold is moist and contains a binder to maintain shape.

Fig. 2.4 Flowchart of Steps in Sand Casting.

Fig. 2.3 Schematic illustration of a sand mold features.

• Cores in the Mold Cavity:

– The mold cavity - the external surfaces of the cast part.

– A core, placed inside the mold cavity to define the interior geometry of part. In sand

casting, cores are made of sand.

• Gating System - Channel through which molten metal flows into cavity a down sprue,

through which metal enters a runner.

– At top of down sprue, a pouring cup to minimize splash and turbulence.

• Riser - Liquid metal reservoir to compensate for shrinkage during solidification.

– The riser must be designed to freeze after the main casting solidifies.

The gating systems refer to the elements which are connected with theflow of molten metal

from the ladle to the mold cavity. These elements are the pouring basin, sprue, sprue base,

runner, runner extension, ingate, and riser, figure 2-5. Any designed gating system should aim

at providing a defect free casting. The gating system should provide;

Fig.2-5 Typical gating system.

1. The mold should be filled in the smallest time possible.

2. The metal should flow smoothly into the mold without turbulence.

3. Slag, dross, and other unwanted materials should be allowed to inter the mold cavity.

4. Preventing the aspiration of the atmospheric air.

5. Provide a proper thermal gradient so the casting is cooling without shrinkage cavities and

distortions.

6. No mold erosion.

7. Enough molten metal should reach the mold cavity.

8. The gating system easy to implement and removed.

The mean function of the pouring basin is to reduce the momentum of the liquid flowing into

11

the mold by settling first into it. To reduce or prevent the turbulence of the metal entering to

the sprue the pouring basin should be deep enough. The deep of the basin is 2.5 times the

entrance diameter of the sprue and the radius of smoothen is 25 mm. The metal should be

poured steadily into the pouring basin keeping the ladle as close as possible.

Sprue is the channel through which the molten metal is brought into the parting plane where it

enters the runners and gates to reach the mold cavity. To eliminate the problem of air

aspiration, due to the increase of Sprue base well is a reservoir for metal at the bottom of the

sprue to reduce the momentum of the molten metal. Figure 2-6 shows the reasonable

proportion design of the sprue base well. The cross section area of the sprue bottom half the

runner area and the area of the sprue base well is 5 times the sprue bottom area, Runner is

connecting the sprue to its in-gates (gates) to allowing the metal enter the mold cavity. Its

cross section is a trapezoidal in shape. The gates have various types such as; top gates, bottom

gate, parting gates, and step gates.

Fig. 2-6 sprue base well design.

2.2.1.2 Casting defects (cf. figure 2.7)

Some common defects in castings:

– General Defects

a) Misruns

b) Cold shut

c) Cold shots

d) Shrinkage cavity

– Sand casting defects

e) Penetration

f) Cope has shifted relatively to drag.

g) Pinholes.

12

2.2.2 Die Casting

• The molten metal is injected into mold cavity (die) under high pressure (7-350 MPa)

and pressure maintained during solidification.

• Hot Chamber (Pressure of 7 to 35MPa) (cf. figure 2.8):

– The injection system is submerged under the molten metals (low melting point

metals such as lead, zinc, tin and magnesium).

• Cold Chamber (Pressure of 14 to 140MPa) (cf. figure 2.8):

13

– External melting container (in addition aluminum, brass and magnesium).

Fig. 2.8 Hot-Chamber Die Casting.

Fig. 2.9 Cold Chamber Die Casting

Fig. 2.7 Casting defects.

• Molds are made of tool steel, mold steel, tungsten and molybdenum.

• Single or multiple cavities.

• Lubricants and Ejector pins to free the parts.

• Venting holes and passageways in die.

• Formation of flash that needs to be trimmed.

• Advantages

– High production, Economical, close tolerance, good surface finish, thin

sections, rapid cooling.

• Disadvantages:

– Generally limited to metals with low metal points.

– Part geometry must allow removal from die cavity.

2.3 Aluminum Production

2.3.1 Casting compositions:

are described by a three-digit system followed by a decimal value. The decimal .0 in all

cases pertains to casting alloy limits. Decimals .1, and .2 concern ingot compositions, which

after melting and processing should result in chemistries conforming to casting specification

requirements. Alloy families for casting compositions are:

1xx.x Controlled unalloyed (pure) compositions, especially for rotor manufacture.

2xx.x Alloys in which copper is the principal alloying element, but other alloying

elements may be specified.

3xx.x Alloys in which silicon is the principal alloying element, but other alloying

elements such as copper and magnesium are specified.

4xx.x Alloys in which silicon is the principal alloying element.

5xx.x Alloys in which magnesium is the principal alloying element.

6xx.x Unused.

7xx.x Alloys in which zinc is the principal alloying element, but other alloying

elements such as copper and magnesium may be specified.

8xx.x Alloys in which tin is the principal alloying element.

9xx.x Unused.

Magnesium: is the basis for strength and hardness development in heat-treated Al-Si

alloys and is commonly used in more complex Al-Si alloys containing copper, nickel, and

14

other elements for the same purpose. The hardening-phase Mg2Si displays a useful solubility

limit corresponding to approximately 0.70% Mg, beyond which either no further

strengthening occurs or matrix softening takes place. Common premium-strength

compositions in the Al-Si family employ magnesium in the range of 0.40 to 0.070%.

Manganese: is normally considered an impurity in casting compositions and is controlled

to low levels in most gravity cast compositions. Manganese is an important alloying element

in wrought compositions through which secondary foundry

compositions may contain higher manganese levels. In the absence of work hardening,

manganese offers no significant benefits in cast aluminum alloys. Some evidence exists,

however, that a high-volume fraction of MnAl6 in alloys containing more than 0.5% Mn may

beneficially influence internal casting soundness. Manganese can also be employed to alter

response in chemical finishing and anodizing.

Silicon: The outstanding effect of silicon in aluminum alloys is the improvement of

casting characteristics. Additions of silicon to pure aluminum dramatically improve fluidity,

hot tear resistance, and feeding characteristics. The most prominently used compositions in all

casting processes are those of the aluminum-silicon family. Commercial alloys span the

hypoeutectic and hypereutectic ranges up to about 25% Si. In general, an optimum range of

silicon content can be assigned to casting processes. For slow cooling-rate processes (such as

plaster, investment, and sand), the range is 5 to 7%, for permanent mold 7 to 9%, and for die

casting 8 to 12%. The bases for these recommendations are the relationship between cooling

rate and fluidity and the effect of percentage of eutectic on feeding. Silicon additions are also

accompanied by a reduction in specific gravity and coefficient of thermal expansion. Some

grade designation for aluminum association and composition can be seen in table 3.2.

2.3.2 Quality Control

The most effective method of determining the combined consequences of chemistry,

material condition, and heat treatment is the determination of tensile strength, yield strength,

and elongation. This is often done by testing separate cast tensile specimens. These values

most conclusively indicate the acceptability of a product relative to specification

requirements. Hardness can be established as an acceptance criterion through negotiation, but

it is less adequate in aluminum alloys than in other metal systems for control purposes.

Hardness in aluminum corresponds only approximately to yield strength, and although

15

hardness can be viewed as an easily measurable indicator of material condition, it is not

normally accurate enough to serve as a guaranteed limit. Electrical conductivity only

approximates material condition in cast or cast and heat treated structures, and it remains

excessively variable for most control purposes.

Table 2.2 Some grade designation and composition of aluminum casting alloys.

16

Typical and minimum mechanical-property values commonly reported for castings.

Mechanical test methods of particular aluminum alloys are determined using separately cast

test bars that are 12 in. diameter (for sand and permanent mold castings) or 14 in. diameter

(for die castings). As such, these values represent properties of sound castings, 13 or 6 mm

(12or 14in.) in section thickness, made using normal casting practice; they do not represent

properties in all sections and locations of full-size production castings. Typical and minimum

properties of test bars, however, are useful in determining relative strengths of the various

alloy/temper combinations. Minimum properties--those values listed in applicable

specifications--apply, except where otherwise noted, only to separate cast test bars. These

values, unlike minimum values based on bars cut from production castings, are not usable as

design limits for production castings.

However, they can be useful in quality assurance. Actual mechanical properties, whether of

separately cast test bars or of full-size castings, are dependent on two main factors:

Alloy composition and heat treatment

Solidification pattern and casting soundness

Some specifications for sand, permanent mold, plaster, and investment castings have

defined the correlation between test results from specimens cut from the casting and

separately cast specimens. A frequent error is the assumption that test values determined from

these sources should agree. Rather, the properties of separately cast specimens should be

expected to be superior to those of specimens machined from the casting. In the absence of

more specific guidelines, one rule of thumb defines the average tensile and yield strengths of

machined specimens as not less than 75% of the minimum requirements for separately cast

specimens, and elongation as not less than 25% of the minimum requirement. These relations

may be useful in establishing the commercial acceptability of parts in dispute. Test

Specimens: Accurate determination of mechanical properties of aluminum alloy castings (or

of castings of any other metal) requires proper selection of test specimens. For most wrought

products, a small piece of the material often is considered typical of the rest, and mechanical

properties determined from that small piece also are considered typical. Properties of castings,

however, vary substantially from one area of a given casting to another, and may vary from

casting to casting in a given heat. If castings are small, one from each batch can be sacrificed

and cut into test bars. If castings are too large to be economically sacrificed, test bars can be

molded as an integral part of each casting, or can be cast in a separate mold. Usually, test bars

are cast in a separate mold. When this is done, care must be taken to ensure that the metal

17

poured into the test-bar mold is representative of the metal in the castings that the test bars are

supposed to represent. in addition, differences in pouring temperature and cooling rate, which

can make the properties of separately cast test bars different from those of production

castings, must be avoided. For highly stressed castings, integrally cast test bars are preferable

to separately cast bars. When integrally cast bars are selected, however, gating and riser must

be designed carefully to ensure that test bars and castings have equivalent microstructure and

integrity. Also, if there are substantial differences between test-bar diameter and wall

thickness in critical areas of the casting, use of integrally cast test panels equal in thickness to

those critical areas, instead of standard test bars, should be considered cf. table 2.3.

ASTM E8 defines the test bars suitable for evaluation of aluminum castings. The use of

test bars cut from die castings is not recommended; simulated service (proof) testing is

considered more appropriate.

2.3.3 Product Classifications

In the United States the aluminum industry has identified its major markets as building

and construction, transportation, consumer durables, electrical, machinery and equipment,

containers and packaging, exports, and other end uses. As described below, each of these

major markets comprises a wide range of end users.

Transportation: Castings are critically important in engine construction; engine blocks,

pistons, cylinder heads, intake manifolds, crankcases, carburetors, transmission housings, and

rocker arms are proven components. Brake valves and brake calipers join innumerable other

components in car design importance. Cast aluminum wheels continue to grow in popularity.

Marine Applications: Aluminum is commonly used for a large variety of marine

applications, including main strength members such as hulls and deckhouses, and other

applications such as stack enclosures, hatch covers, windows, air ports, accommodation

ladders, gangways, bulkheads, deck plate, ventilation equipment, lifesaving equipment,

furniture, hardware, fuel tanks, and bright trim. In addition, ships are making extensive use of

welded aluminum alloy plate in the large tanks used for transportation of liquefied gases.

Casting alloys are used in outboard motor structural parts and housings subject to continuous

or intermittent immersion, motor hoods, shrouds, and miscellaneous parts, including fittings

and hardware. Additional marine applications are in son buoys, navigation markers, rowboats,

canoes, oars, and paddles.

Motors and Generators: Aluminum has long been used for cast rotor windings and

18

structural parts. Rotor rings and cooling fans are pressure cast integrally with bars through

slots of the laminated core in caged motor rotors. Aluminum structural parts, such as stator

Table 2.3 Typical (and minimum) tensile properties of aluminum casting alloys.

Elongation(a)

in 50 mm

(2 in.), %

0.2% offset

yield

strength(a)

Ultimate

tensile

strength(a)

Temper

Alloy

MPa MPa

Sand casting alloys

270

39

270

T6

C355.0

2 172 248

6 124 164 F 356.0

2 138 172 T51

6 83 159 F A356.0

3 124 179 T51

6 207 278 T6

3 138 207 T71

5 90 172 E 357

3 117 179 T51

2 296 345 T6

3 234 278 T7

5 124 179 F

356

2

138

186

T51

5 186 262 T6

3 138 207

6 165 221 T7

10 207 283 T61 A356

5 …. 255

6 103 193 F 357

4 145 200 T51

5 295 360 T6

3 ….. 310

19

frames and end shields, are often economically die cast. Their corrosion resistance may be

necessary in specific environments--in motors for spinning natural and synthetic fiber, and in

aircraft generators when light weight is equally important, for example.

Coal Mine Machinery: The use of aluminum equipment in coal mines has increased in

recent years. Applications include cars, tubs and skips, roof props, nonsparking tools, portable

jacklegs, and shaking conveyors. Aluminum is resistant to the corrosive conditions associated

with surface and deep mining. Aluminum is self cleaning and offers good resistance to

abrasion, vibration, splitting, and tearing.

Jigs, Fixtures, and Patterns: Thick cast or rolled aluminum plates and bar, precisely

machined to high finish and flatness, are used for tools and dies. Plate is suitable for hydro

press form blocks, hydro stretch form dies, jigs, fixtures, and other tooling. Aluminum is used

in the aircraft industry for drill jigs, as formers, stiffeners and stringers for large assembly jigs,

router bases, and layout tables. Used in master tooling, cast aluminum eliminates war page

problems resulting from uneven expansion of the tool due to changes in ambient temperature.

Large aluminum bars have been used to replace zinc alloys as a fixture base on spar mills with

weight savings of two-thirds. Cast aluminum serves as match plate in the foundry industry.

2.3.4 Product Design Considerations

* Geometric simplicity:

- Simplifies mold-marking.

- Reduces the need for cores.

- Improves the strength of the casting.

* Corners on the casting:

- Sharp corners and angles should be avoided, since they are sources of stress

concentrations and may cause hot tearing and cracks.

- Generous fillets should be designed on inside corners and sharp edges should be

blended.

* Draft Guidelines:

- In expendable mold casting, draft facilitates removal of pattern from mold. Draft

= 1 for sand casting.

- In permanent mold casting, purpose is to aid in removal of the part from the

mold. Draft = 2 to 3 for permanent mold processes.

20

- Similar tapers should be allowed if solid cores are used

* Draft (cf. figure 2.8)

- Minor changes in part design can reduce need for coring.

Fig. 2.10 Design change to eliminate the need for using a core:

(a) original design, and (b) redesign.

* Dimensional Tolerances and Surface Finish:

- Significant differences in dimensional accuracies and finishes can

be achieved in castings, depending on process.

- Poor dimensional accuracies and finish for sand casting.

- Good dimensional accuracies and finish for die casting and investment casting

.

* Machining Allowances:

- Almost all sand castings must be machined to achieve the required

dimensions and part features.

- Additional material, called the machining allowance, is left on the casting in

those surfaces where machining is necessary

- Typical machining allowances for sand castings are around 1.5 and 3 mm

(1/16 and 1/4 in)

- Tolerance and Surface Roughness for Various Casting Processes.

2.3.5 Selection of Casting Process

There are many factors that affect selection of a casting process for producing a specific

aluminum alloy part. Some of the important factors in sand, permanent mold,

and the casing affecting selection of casting process for aluminum alloys are discussed in

Table 2.4. The most important factors for all casting processes are:

21

Feasibility and cost factors.

Quality factors.

In terms of feasibility, many aluminum alloy castings can be produced by any of the

available methods. For considerable number of castings, however, dimensions or design

features automatically determine the best casting method. Because metal molds weigh from

10 to 100 times as much as the castings they are used in producing, most very large cast

products are made as sand castings rather than as die or permanent mold castings.

22

Table 2.4 Factors affecting selection of casting process for aluminum alloys.

Small castings usually are made with metal molds to ensure dimensional accuracy. Some parts

can be produced much more easily if cast in two or more separate sections and bolted or

welded together. Complex parts with many undercuts can be made easily by sand, plaster, or

investment casting, but may be practically impossible to cast in metal molds even if sand

cores are used. When two or more casting methods are feasible for a given part, the method

used very often is dictated by costs. As a general rule, the cheaper the tooling (patterns,

molds, and auxiliary equipment), the greater the cost of producing each piece. Therefore,

number of pieces is a major factor in the choice of a casting method. If only a few pieces are

to be made, the method involving the least expensive tooling should be used, even if the cost

of casting each piece is very high. For very large production runs, on the other hand, where

cost of tooling is shared by a large number of castings, use of elaborate tooling usually

decreases cost per piece and thus is justified. In mass production of small parts, for example,

costs often are minimized by use of elaborate tooling that alloys several castings to be poured

simultaneously. Die castings are typical of this category. Quality factors are also important in

the selection of a casting process. When applied to castings, the term quality refers to both

degree of soundness (freedom from porosity, cracking, and surface imperfections) and levels

of mechanical properties (strength and ductility). It is evident that high cooling rate is of

paramount importance in obtaining good casting quality. The tabulation below presents

characteristics ranges of cooling rate for the various casting processes however, it should be

kept in mind that in die casting, although cooling rates are very high, air tends to be trapped in

the casting, which gives rise to appreciable amounts of porosity at the center. Extensive

research has been conducted to find ways of reducing such porosity; however, it is difficult if

not impossible to eliminate completely, and die castings often are lower in strength than low-

pressure or gravity-fed permanent mold castings, which are sounder in spite of slower cooling.

Alloys of aluminum are used in die casting more extensively than alloys of any other base

metal. In the United States alone, about 2.5 billion dollars worth of aluminum alloy die

castings is produced each year. The die casting process consumes almost twice as much

tonnage of aluminum alloys as all other casting processes combined. Die casting is especially

suited to production of large quantities of relatively small parts. Aluminum die castings

weighing up to about 5 kg (10 lb) are common, but castings weighing as much as 50 kg (100

lb) are produced when the high tooling and casting-machine costs are justified.

1.2 Problem Statement Objective

1. Identify the most relevant needs from an open ended problem (Problem

23

description – Comprehension).

2. Discover a solution strategy using a suitable heuristic (Road map planning –

Application).

3. Breakdown an open ended problem into its main elements. (Problem

breakdown – Analysis).

4. Develop alternative solutions by using brainstorming technique (Problem

formulation – Synthesis).

5. Choose the best solution, from those developed, using specified criteria

(Solution Assessment – Evaluation).

6. Implement the solution with an appropriate level of details (Problem solving –

Application).

7. Test the solution and analyze the results to determine if they are sufficient

(Solution - validation – Analysis).

8. Evaluate the solution and argue suitable improvements and changes (Solution

evaluation and improvement- Evaluation).

9. Demonstrate work harmoniously and effectively in a team to solve open ended

problems (Team dynamics – Application).

10. Demonstrate effective communication, resolve team conflicts, apply social

team norms, prepare team rules, organize and delegate work as needed, and

manage available resources (Team Communication/Conflict Management –

Application).

11. Demonstrate time management for team meetings and to ensure that all tasks

are completed and submitted on time (Self-Management –Application).

12. Write high quality engineering journals and prepare professionally the required

graphs and tables. (Written skills - Synthesis).

13. Plan, prepare and deliver clear and correct oral presentations using professional

visual aids (Oral skills- Synthesis).

14. Collect information of a new content by asking key questions and by using a

variety of sources such as internet, textbooks, etc. (Facing new concepts –

Synthesis).

15. Evaluate personal performance and progress as well as that of teammates using

specific criteria (self and peer evaluation – Evaluation).

24

1-3 Problem justification and Outcomes

a. an ability to apply knowledge of mathematics, science, and engineering

fundamentals.

b. an ability to design and conduct experiments, and to critically analyze

and interpret data.

c. an ability to design a system, component or process to meet desired

needs.

d. an ability to function in multi-disciplinary teams.

e. an ability to identify, formulate and solve engineering problems.

f. an understanding of professional and ethical responsibility.

g. an ability for effective oral and written communication.

h. the broad education necessary to understand the impact of engineering

solutions in a global and societal context.

i. a recognition of the need for, and an ability to engage in life-long learning.

j. a knowledge of contemporary issues.

k. an ability to use the techniques, skills, and modern engineering tools

necessary for engineering practice.

1-4 Problem Constraints

Product Design Considerations.

Determined the aluminum alloys.

Design (pattern – core – gate – riser and sprue).

Executive sand casting processes.

Machining and surface finish.

Experimental Tests.

Cost evaluation.

25

CHAPTER 3

EXPERIMENTAL PROCEDURES

3. 1 Materials and Melting

The materials tested were produced in a private foundry at JAZAN. Commercial

aluminum alloy with copper, nickel and magnesium called Y-alloy was melted in a basic

furnace with a melt capacity of 0.5 ton/hr. The melt was then superheated and held at 750 0C

for 60 min. It was then tapped at approximately 700 0C into a preheated ladle before casting.

3. 2 Casting Procedure

The pattern design has been made applying the reverse engineering design from the

original product (4 engine piston TOYOTA). A full-sized model of the part slightly enlarged

to account for shrinkage and machining allowances in the casting. Silica (SiO2) or silica

mixed with other minerals with good refractory properties for capacity to endure high

temperatures of small grain size yields better surface finish on the cast part. Large grain size

is more permeable, allowing gases to escape during pouring. Sand was held together by a

mixture of water and bonding clay typical max: 90% sand, 3% water, and 7% clay as shown

In figure 3.1.

Fig. 3.1 Sand mixture of water and clay.

Casting processes begin by separating the mold into two halves (1st and 2

nd molds) and third

mold by sprue. The cavity in the sand mold was formed by packing sand around the pattern

26

(cut the original piston into symmetrical haves) cf. figure 3.2. The third mold had the sprue

and the mold must also contain riser and gating system. A new sand mold must be made for

each part produced.

Pattern Packing sand around the pattern (1st mold)

(2nd

mold) (3rd

mold)

Cavity by removing the pattern Riser and Gating system

Fig. 3.2 Casting Processes

27

The mold was baked to improve strength Skin-dried mold - drying mold cavity surface of a

green-sand mold to a depth of 10 to 25 mm, using torches or heating lamps c.f. figure 3.3. The

conventional aluminum alloy were poured from a single preheated ladle at pouring

temperature in 680 0C for 5 min cf. figure 3.3. Upon completion of pouring, all castings were

allowed time to cool in the molds and for metal to solidify before shake-out and break up the

mold to remove casting. Clean and inspect casting were done. However, then separate gating

and riser system cf. figure 3.4. Defects are possible in casting, and inspection is needed to

detect their presence.

Fig. 3.3 Melting and pouring process.

Fig 3.4 Product after casting

28

Machining processes have been done in private machining workshop at JAZAN. Lathe

machine, made in India , was used c.f Figure 3.5. Piston with ring has stander diameter of

size: 80.50 mm and hole of radius 12 mm.

Piston size and ring groove had 3 sizes: 1- two rings. 2- Compression ring. 3- Oil ring.

Piston pin and circle ring and drilling using high speed steel tool and carbide bite of twist

drill tool.

Machining conditions were:

- Rotation speed 3000 ( rpm),

- Depth of cut 2.5 (mm).

- Feed rate 1 (mm/ rev)

External machining Internal machining

Drilling Making and Original Piston

Fig 3.5 Machining Processes

29

3-2 Mathematical models and formulations

A. TOTAL HEAT ENERGY REQUIRED:

H=ρV[Cs(Tm-To)+Cl (Tp-Tm)]

Where:

ρ=density, V=volume, Cs=specific heat for solid

Cl=specific heat for liquid, Tm=melting temperature

To=starting temperature, Tp=pouring temperature

B. SOLIDIFICATION TIME:

Chorine’s empirical relationship: solidification as a function of the size and shape:

TST =Cm (V/A)

Where:

V=volume A=surface area n=2

C. VALUE OF THE WEIGHT

Equations 1 and 2 show THAT should be put above the upper surface of

the cope to prevent the flooding of the molten metal at the separating plan

between the cope and drag:

(1) Fm = Ap ρ (h - c)

Where;

Fm Metal static pressure force, N

Ap The projected area of the casting at the parting line.

ρ Density of the molten metal.

(h-c) The height of the head of metal.

(2) W = Ws - P - Fm

Where;

W THE net weight.

Ws The weight of the sand in the cope and the weight of the cope.

P Buoyant force, N

D. GATING SYSTEM DESIGN

Equation shows the relation between the top area (At) and the choke section

Area (Ac) at the bottom of the sprue, as shown in figure. 2-6.

30

(1) A= W \ ρtc (2gH)1\2

Where;

A choke area, mm2

W casting mass, kg

t pouring time, s

ρ density of the molten metal, kg/mm3

g acceleration due to gravity, mm/s2

H effective metal head (eq. 2-6), mm

C efficiency factor, table 3-1, which is a function of gating system used.

Table 3-1 Efficiency coefficients, C for various types of gating systems.

(2) H= h - (P\2c)

Where;

H sprue height, mm

P distance between the parting line and the upper surface of the casting, mm

c height of the casting, mm

D. FEASIBIILITY STUDIES:

𝟏. 𝐐𝐁.𝐄 =𝐅

𝐚−𝐯

Where:

QB.E: break-even quantity. Units

F: fixed cost. SR

a: selling price. SR/unit

v: variable cost. SR/unit

𝟐. 𝐌𝐒 =𝐐𝐏𝐥𝐚𝐧𝐧𝐞𝐝−𝐐𝐁.𝐄

𝐐𝐁.𝐄 × 𝟏𝟎𝟎

Where:

MS: Margin of Safety.

31

CHAPTER 4

RESULTS AND DISCUSSION

Through this chapter some results will be discussed to the routine, procedures

discussed in the previous chapter. The procedure begins with the views of the required

casting, the viewing of the required pattern, and then the calculations of the gating system and

mold dimensions.

4-1 Pattern design:

As mentioned before we used the reverse engineering design for pattern design by cut

the original piston into symmetrical haves. But, according to the shrinkage degree (cf. table

2.1) and machining allowance (cf. section 2.3.4), the dimensions of 4 cavities after takeoff the

patterns for making 4 pistons in the mold must be larger than the original piston.

The final dimensions of the making piston after casting can be seen in the Drawing package

at the appendix “D”.

4-2 Sprue hight .

Equation of sprue :

𝑯 = 𝒉 −ῤ𝟐

𝟐𝒄

ῤ=2.79 g/𝒎𝟑 = 𝟐.𝟕𝟗 ∗ 𝟏𝟎𝟑 𝒈/𝒎𝒎𝟑

C=0.73 mm frome table . h= 80mm

H=80 – (𝟐.𝟕𝟗∗𝟏𝟎−𝟑)𝟐

𝟐∗𝟎.𝟕𝟑= 𝟕𝟗.𝟗𝟗 ≅ 𝟖𝟎 𝒎𝒎

32

4-3 SOLIDIFICATION TIME

𝑻𝑺𝑻 = 𝒄𝒎 ∗ (𝒗

𝑨)𝒏

cm= 240 w/m.𝒄𝟎

𝒗 =𝟑.𝟔𝟎

𝟐.𝟗𝟕∗𝟏𝟎−𝟔 𝒎𝒎𝟑 A=266400 𝒎𝒎𝟐

n = 2

𝑻𝑺𝑻 = 𝟐𝟒%(

𝟑.𝟔𝟎𝟐.𝟗𝟕 ∗ 𝟏𝟎−𝟔

𝟐𝟔𝟔𝟒𝟎𝟎)𝟐 = 𝟒𝟗𝟔𝟖.𝟔𝟏

𝐰

𝐦. 𝒄𝟎 .𝐦𝐦𝟐

4-4 gating system design:

𝑨 =𝒘

𝒅𝒕𝒄 𝟐𝒈𝒉

W=3.60 kg

d = 2.97*𝟏𝟎−𝟔 𝒌𝒈/𝒎𝒎𝟑

t= 20 s c=0.9 g=980 mm/𝒔𝟐 H =19.19 mm

𝑨 =𝟑.𝟔𝟎

𝟐.𝟕𝟗 ∗ 𝟏𝟎−𝟑 ∗ 𝟐𝟎 ∗ 𝟎.𝟗 ∗ 𝟐 ∗ 𝟗𝟖𝟎 ∗ 𝟏𝟗.𝟏𝟗= 𝟑𝟒𝟕.𝟐𝟐 𝒎𝒎𝟐

33

CHAPTER 5

FEASIBIILITY STUDIES AND MARKET NEEDS

3000 SR The rent of foundry

40000 SR LABOR COST

2500 SR The cost of pump

25000 SR FARNACES

4000 SR Molds cost

Total fixed cost (f) =74500 SR

40 SR/unit Material cost

3 SR/unit Sand cost

1 SR/unit Energy cost

Total variable cost (v) =44 SR/unit

Expected :

Selling price of making product (a) = 200 SR/unit

Calculated :

Quantity of break Even (𝑸𝑩.𝑬 ):

𝑸𝑩.𝑬 =𝑭

𝒂 − 𝒗=

𝟕𝟒𝟓𝟎𝟎

𝟐𝟎𝟎 − 𝟒𝟒= 𝟒𝟕𝟕.𝟓𝟔 ≅ 𝟒𝟕𝟖 𝒖𝒏𝒊𝒕

Cost = revenue

Revenue = 𝒂 × 𝑸𝑩.𝑬 = 𝟐𝟎𝟎 × 𝟒𝟕𝟖 = 𝟗𝟓𝟔𝟎𝟎 𝑺𝑹

Cost :

= 𝑭 + 𝑽 × 𝑸𝑩,𝑬 = 𝟕𝟒𝟓𝟎𝟎 + 𝟒𝟒 × 𝟒𝟕𝟖 = 𝟗𝟓𝟓𝟑𝟐 𝑺𝑹

Profit = revenue – cost ≅ 𝟎

Planned :

At Quantity (𝑸𝒑𝒍𝒂𝒏𝒏𝒆𝒅) = 𝟕𝟎𝟎 𝒖𝒏𝒊𝒕

Revenue = 𝒂 × 𝑸𝒑𝒍𝒂𝒏𝒏𝒆𝒅 = 𝟐𝟎𝟎 × 𝟕𝟎𝟎 = 𝟏𝟒𝟎𝟎𝟎𝟎 𝑺𝑹

COST = 𝑭 + 𝑽 × 𝑸𝑷𝒍𝒂𝒏𝒏𝒆𝒅 = 𝟕𝟒𝟓𝟎𝟎 + 𝟒𝟒 × 𝟕𝟎𝟎 = 𝟏𝟎𝟓𝟑𝟎𝟎 𝑺𝑹

Calculate :

Profit = revenue – cost=

At Quantity (𝑸𝒑𝒍𝒂𝒏𝒏𝒆𝒅)𝟕𝟎𝟎 𝒖𝒏𝒊𝒕

Margin of safety (MS) = 𝟕𝟎𝟎−𝟒𝟕𝟖

𝟒𝟕𝟖∗ 𝟏𝟎𝟎 = 𝟒𝟔 %

34

Fig. The relationship between the cost and revenue values (Break Even Point).

35

CHAPTER 6

CONCLUSION AND RECOMMENDATIONS

A. Conclusion

1- Successful production of aluminum 4 engine pistons of Toyota was produced.

2- Reverse engineering design was used to prepare the pattern.

3- Pouring sprue, riser, gating system were designed for sand.

4- AutoCAD used to produce the 3D model of the casting object.

5- Fitting and machining operations for the final dimensions of making product have

been done.

6- Cost evaluation of selected product was calculated.

B- Recommendations

(1) Produce the aluminum 4 engine pistons by sand casting instead of die casting.

(2) Sand casting is cheaper and economically than the die casting.

(3) Using easily the reverse engineering design to make the pattern.

(4) Suitable machining conditions for good surface finishing.

(5) Take care with the design of riser, gates and sprue design to produce good quality

without defects.

(6) Considering the shrinkage rate for the selected materials.

36

1. APPENDIXES

A: Project Team with assigned responsibilities,

1- Fahad Mohammed Alshahrani

2- Mohammed Abdo Moukley

3- Abdul Rahman Hassan Jed

4- Hayaf Menahi Ashahrani

5- Abdullah Mohammed Abu Alsummah

B: Faculty Advisers and Industry sponsors …………..………………..

C: Project Budget and Expenses to date …………..………………….

D: Drawing package :

1-Orgenal Prod

37

(D-1)-Orgenal product

38

(D-2) . Design of Pattern (Reverse Engineering)

39

(D-3)-1st Sand Mould (Base of Piston)

(D-4)-2nd

Sand Mould (Body of Piston)

40

(D-5)-3rd

Sand mold (Sprue )

(D-6)-Assembly after cleaning

41

(D-7)-Making Product After Casting Before Machining

42

E: Manufacturing procedures, Test procedures and Test reports

Reverse engineering has its origins in the analysis of hardware for commercial or military

advantage. The purpose is to deduce design decisions from end products with little or no

additional knowledge about the procedures involved in the original production. The same

techniques are subsequently being researched for application to legacy software systems, not

for industrial or defense ends, but rather to replace incorrect, incomplete, or otherwise

unavailable documentation.

Reasons for reverse engineering: (Re) development of documentation: Reverse engineering

often is done because the documentation of a particular device has been lost (or was never

written), and the person who built it is no longer available. Integrated circuits often seem to

have been designed on obsolete, proprietary systems, which means that the only way to

incorporate the functionality into new technology is to reverse-engineer the existing chip and

then re-design it.

Software Modernization: reverse engineering is generally needed in order to understand the

'as is' state of existing or legacy software in order to properly estimate the effort required to

migrate system knowledge into a 'to be' state. Much of this may be driven by changing

functional, compliance or security requirements.Software Maintenance: reverse engineering of

software can provide the most current documentation necessary for understanding the most

current state of a software system.Product analysis: To examine how a product works, what

components it consists of, estimate costs, and identify potential patent infringement. Digital

update/correction: To update the digital version (e.g. CAD model) of an object to match an

"as-built" condition. Security auditing: Acquiring sensitive data by disassembling and

analysing the design of a system component. Military or commercial espionage: Learning

about an enemy's or competitor's latest research by stealing or capturing a prototype and

dismantling it.

Removal of copy protection, circumvention of access restrictions.

Creation of unlicensed/unapproved duplicates.

Academic/learning purposes.

Curiosity.

Competitive technical intelligence (understand what your competitor is

42

actually doing, versus what they say they are doing).

Learning: learn from others' mistakes. Do not make the same mistakes that

others have already made and subsequently corrected

F: Technical reports or evaluation…………………………

All subjects that have been applied in our project.

Contents

Subject

name

Code No

Basic principles of computer operations and

programmers

Introduction

to Compute

CompG 101 1

Types of drawings:perspectives,

axonometric, isometrics.Obliqueandortho

graphic projections.

Engineering

Drawing (1)

Eng G. 111 2

classification of engineering metals, Mechanical

properties study, their chemical and physical

properties. Study of Instrument Tools used to

measure dimensions. Ready to handwork and

equipment use and hand tools for workshop

Production

and

Workshop

Technology

Eng M. 121 3

an introduction toward materials structure,

composition, processing and mechanical

properties relationships.

Materials

Science (1)

EngM212 4

an introduction to materials science and

engineering.

Materials

Engineering

EngM 218 5

Geometry: conical sections, analytic geometry in

three dimensions including lines, planes and

second order surfaces, cylindrical and spherical

coordinates.

Math. (2)

Math. 219 6

helps in solving some popular engineering

applications by applying their corresponding

algorithm.

Computer

for

Engineers

EngG 221 7

understand how the various mechanical

properties are measured and what these

properties represent; they may be called upon to

design structures/components using

predetermined materials.

Strength of

Material

and

Material

Tests

Eng M222 8

Basic principles of Drawings and Using computer

programmers AutoCad.

Engineering

Drawing 2

224 Eng-2. 9

Energy equation and its applications.

Mechanical

Engineering

(1)

EngM 228 10

It deals with: formatting, guidelines, components

of a report, writing a section, referencing of

sources, and the technical language appropriate

to a quality report.

Technical

report

writing

EngG301 11

using furnaces for heat treatment – heat

treatment for metals and alloys.

Material

Science (2)

EngM316 12

project valuation and analysis of economical

feasibility study, risk analysis, assertion and

responsibility feeling, techniques of cost

estimation, market survey.

Engineering

Economy

Eng G 321 13

machine design. This includes the principles

concepts and the factors affected the design and

construction details.

Mechanical

Engineering

(2)

EngM328 14

using software CAD programs in drawing and

calculations.

Designof

Machine

Elements(1)

EngM 411 15

fundamental knowledge of different types of

manufacturing processes (casting processes).

Production

Engineering

(2)

EngM412 16

Theory of material removal processes (turning

and related operations, drilling and related

operations.

Production

Engineering

(3)

EngM420 17

fundamentals of heat transfer by conduction,

convection, and radiation.

Heat

Transfer

EngM 424 18

44

CHAPTER 6

REFERENCES

1. R.K. Wyss and R.E. Sanders, Jr., "Microstructure-Property Relationship in a 2xxx

Aluminum Alloy with Mg Addition," Metall. Trans. A, Vol. 19A, 1988, p 2523-2530

2. "Registration Record of International Alloy Designations and Chemical Composition

Limits for Wrought Aluminum and Wrought Aluminum Alloys," PP/2M/289/A1,

Aluminum Association, Feb 1989.

3. "Registration Record of Aluminum Association Alloy Designations and Chemical

Composition Limits for Aluminum Alloys in the Form of Casting and Ingot," Aluminum

Association, Jan 1989.

4. R.L. Antona and R. Moschini, Metall. Sci. Technol., Vol 4 (No. 2), Aug 1986, p 49-59 .

5. D.M. Stefanescu and C.S. Kanetkar, "Modeling of Microstructural Evolution of

Cast Iron and Aluminum-Silicon Alloys," Paper 19, presented at the 54th International

boundary Congress, New Delhi, India, 1987.

6. C.S. Kanetkar, Ph.D. dissertation, The University of Alabama, 1988.

7. Kaushish J.P., “Manufacturing Processes”, Asoke K. Ghosh Prentical Hall of India Private

limited, New Delhi, 2nd Edition, 2010.

8. Wong, Yin Ying, Investigation mechanical properties and microstructure of aluminum

silicon alloy using sand casting (2010) Eng. D thesis, University Malaysia.

9. S.P. Nikanorova et al, Structural and mechanical properties of Al–Si alloys obtained by fast

cooling of a levitated melt, Materials Science and Engineering A (2005) 63–69.

10. ASM International, Introduction to Aluminum-Silicon Casting Alloys, 2004. All Rights

Reserved. Aluminum-Silicon Casting Alloys: Atlas of Microfractographs.

11. R. FRANCIS* AND J. SOKOLOWSKI, PREDICTION OF THE ALUMINUM SILICON

MODIFICATION LEVEL IN THE Al Si Cu ALLOYS USING ARTIFICIAL NEURAL

NETWORKS Association of Metallurgical Engineers of Serbia, (2007).

12. W. Cui et al, Automatic reverse engineering of input formats. In Proceedings of the 15th

ACM Conference on Computer and Communications Security, pp. 391–402. ACM, Oct

2008.

13. Michael L. Nelson, “ A Survey of Reverse Engineering and Program Comprehension”,

April 19, 1996.

45

BIBLIOGRAPHY

1. ASM Metals Handbook, Vol. 15 – Casting, 9th Edition Metals Handbook, second printing

(1992).

2. Chakrabarti, A. K., “Casting Technology & Cast Alloys”, Asoke K. Ghosh Prentical Hall of

India Private limited, New Delhi, 2005.

3. Bruce J. Black, C. Eng., MIEE, “Workshop Processes, Practices and Materials”, 3th

Ed.,

2004, Bruce J. Black. All rights reserved.

4. Rajput R.K., “A Text of Manufacturing Technology (Manufacturing Processes)”, Laxmi

Publications (P) LTD, New Delhi, 2007.

5. Roa P.N., “Manufacturing Technology Volume 1”, Tata McGraw-Hill Publishing Company

Limited, New Delhi, 3rd Edition, 2009.

6. Eilam, Eldad & Chikofsky, “Reversing: secrets of reverse engineering.”Elliot J. (2007).

John Wiley & Sons. p. 3.

7. Wolfgang Rankl, Wolfgang Effing, Smart Card Handbook (2004).

46

CAPSTONE DESIGN PROJECT

Project Submission and

ABET Criterion 3 a-k Assessment Report

Project Title

DATE: 13 / 7 / 1435

PROJECT ADVISOR Ass. Prof. Dr. Osama Mohamed Hussein Ibrahim

Team Leader: Fahad Mohammed Alshahrani

Team Members- Mohammed Abdo Moukley

Abdul Rahman Hassan Jed

Hayaf Menahi Ashahrani

Abdullah Mohammed Abu Alsummah

Design Project Information

Percentage of project Content- Engineering Science % 30%

Percentage of project Content- Engineering Design % 30%

Other content % All fields must be added to 100% 40% Please indicate if this is your initial project declaration □ Project Initial Start Version or final project form X Final Project Submission Version

Do you plan to use this project as your capstone design project? yes

Mechanism for Design Credit □ Projects in Engineering Design

□ Independent studies in Engineering X Engineering Special Topics

Fill in how you fulfill the ABET Engineering Criteria Program Educational

Outcomes listed below

Outcome (a), An ability to apply knowledge of mathematics,

science, and engineering fundamentals.

Please list here all subjects (math, science, and engineering)

that have been applied in your project. Material Science (Commercial Aluminum Alloys Metallurgical

parameters, Mechanical Properties, Microstructural Analysis, Melting

Furnaces). Casting Processes (Sand and Die castings, Pattern Design,

Core Print, Gates, Pouring Sprue, Riser Feeder, and Runner). Product

Design Considerations (Machining Processes, Cutting Tools, Tolerance

and Fit)

Outcome (b). An ability to design and conduct experiments,

and to critically analyze and interpret data.

In this part, if the project included experimental work for

validation and/or verification purposes, please indicate that.

Practical Tests (Tensile, Hardness, Impact Toughness, Microstructure

Observations, Y-block Cast Specimens). Chemical Compositions Analysis

(Optical Microscope, Photos). Machining Processes (Lathe, Shaper,

Grinding, Hand Tools for Filling). Quality Contort (Temperatures

Measurements, Dimensions Accuracy).

Outcome (c). An ability to design a system, component or

process to meet desired needs within realistic

constraints such as economic, Environmental,

Social, political, ethical, health and safety,

manufacturability, and sustainability

All projects should include a design component. By design we

mean both physical and non physical systems. Reverse Engineering Design was used for Pattern Design.

Sand Mold Design (Core Print, Pouring Sprue, Riser, Runner and Gates)

Outcome (d). An ability to function in multi-disciplinary

teams.

This outcome is achieved 5 students.

However, if the project involved students from other

departments, that would be a plus that is worth to be

highlighted.

Outcome (e). An ability to identify, formulate and solve

engineering problems.

Product design consideration.

Determined the aluminum alloy.

Design (pattern-core-gate-riser and sprue).

Executive sand casting process.

Machine and surface finish.

Outcome (f). An understanding of professional and ethical

responsibility.

Here professional and ethical responsibility depends on the

project context.

Outcome (g). An ability for effective oral and written

communication.

Good report and good presentation will fulfill this outcome.

Outcome (h). The broad education necessary to understand

the impact of engineering solutions in a global

economics, environmental and societal context

.

This outcome is usually fulfilled by highlighting the economic

feasibility of the project, and emphasizing that the project

would not harm the environment and does not negatively affect

human subjects.

Outcome (i). A recognition of the need for, and an ability to

engage in life-long learning.

This outcome is fulfilled by suggesting a plan for future studies

and what else could be done based on the outcome of the

current project.

Outcome (j). A knowledge of contemporary issues.

Extensive literature review by the “students” for the current

state of the art will fulfill this outcome.

Outcome (k). An ability to use the techniques, skills, and

modern engineering tools necessary for

engineering practice.

List all technologies included in the project (hardware and

software)

Sand Casting Processes, Practical Experimental Tests, Microscopic

Examinations, Machine Tools, Quality Control Methods.

By signing below certify that this work is your own and fulfills the criteria

described above

Student Team Signatures _________________________ __________________________

_________________________ __________________________

_________________________ __________________________

Project Advisor Signature _________________________ Date

College Coordinator of Capstone Projects _________________________

Approved By _________________________