Training courses that PSMi can offer to the customers Courses.pdf · Training courses that PSMi can offer to the ... ANSI/ASME Tool Life Testing with Single-Point Turning Tools (B94.55M-1985)

Training courses that PSMi can offer to the

customers:

Trainer: Viktor P. Astakhov is the Tool Research and Application Manager of PSMi

PSMi Courses

This has been gradually changing in manufacturing since the beginning of the 21st century. To

address these issues, leading tool and machine manufacturers have developed a number of new

products—new tool materials and coatings, new cutting inserts and tool designs, and other

aspects of machining in order to increase the efficiency of machining operations in industry by

increasing working speeds, feed rates, tool life, and reliability. Today, it is common to use dry

hobbing with high-speed steel hobs at 80 m/min. Modern grades of polycrystalline diamond

(PCD) tool material allow milling, drilling, and reaming of high-silicon aluminum alloys at

speeds of 1,000-8,000 m/min. Modern grades of carbide tools combined with advanced coatings

allow machining of alloyed steels at speeds of 300-600 m/min.

Nowadays, machines with great ranges of speed and feed and high-precision spindles, high-

pressure coolant supplies; high-precision hydraulic and shrink-fit tool holders; tool pre-setting

machines (Zollar and Kelch, for example); advanced machine controllers; and many other

improvements have become common. In tool manufacturing system, CNC tool grinders (for

example, EWAG, Walter, Star, ANKA, etc.) and tool inspection machines (for example, Helicheck,

Zoller/genius 3) were introduced. In the tool design, three-dimensional (3D) solid modeling

software packages were introduced to help tool designers. New tool materials and advanced

grades of the existing tool materials, including nano-coatings, were introduced.

The cutting tool manufacturers were pushed to the forefront to show their capability to produce

new tools to address new challenges in metal machining – high productivity rates, low-cost

parts, great quality, suitable tool reliability, particularly for unattended manufacturing lines and

cells. In light of the trainer’s experience, they, together with all metal cutting-related academics

and researchers, failed miserably to meet this goal. The root cause of the failure of the tool

manufacturers is the lack of specialists capable of understanding the fundamental principles of

metal cutting and tool design as well as tool application aspects.

PSMi offers a unique set of courses on machining because:

1. PSMi has a unique experience managing cutting tools for various industries (e.g.,

automotive, medical, aerospace). Being directly responsible for efficiency, quality and

reliability of machining operations, PSMi gained a unique combination of knowledge on

tool performance, tool design, tool materials, etc.

2. PSMi specialists combine knowledge and experience from academia and industry.

3. PSMi is not a tool manufactures so it acts as an independent tool quality evaluator.

However, PSMi develops its own tool designs correcting drawbacks of cutting tools.

4. PSMi involves in research and development activities on metal cutting and cutting tools.

5. PSMi involves in publishing of great variety of materials including academic books and

monographs, journal papers and articles, reference materials, manuals, industrial

reports, etc.

No one other tool commodity management company or even a tool manufacturing

company possesses such a unique experience.

Turning

Many industrial seminars, promotion materials, industrial

drives and even papers in scientific journals concentrate

attention on advanced techniques, such as high-speed turning,

hard turning, minimum quantity lubricant or near dry turning,

ultra-precision turning of advanced work materials. It may

appear that all the problems within traditional turning

techniques are solved and no further research and development

is needed. Multiple colorful catalogs with high-quality realistic

pictures of leading tool manufacturers enhance this notion even

further creating an impression that one can select the best tool

and machining conditions for a given application just following a

few very simple well-defined steps.

It will be shown in this training course that nothing could be

further from the truth. It is true that the allowable turning

speeds and feeds almost doubled over the last decade. It became

possible due to significant improvements in the tools

manufacturing quality including the quality of their components

(carbides, coatings, etc.), implementation of better turning

machines equipped with advanced controllers as well as their

proper maintenance, application of better coolants, better

training of engineers and operators and many other factors.

However, the actual tool performance and process efficiency

(the cost per part) vary significantly from one application to

another, from one manufacturing plant to the next depending on

an overwhelming number of variables. Optimum performance in

turning is achieved when the combination of the cutting speed

(rpm), feed, tool geometry, carbide grade including its coating,

and coolant parameters is selected properly depending upon the

work material (its hardness, composition and metallurgical

structure), machine conditions, and the quality requirements to

the machined parts. To get the most out of a tuning job, one

must consider the complete machining system, which includes

everything related to the operation. Such a consideration is

known as the system engineering approach according to which

the machining system should be distinguished and analyzed for

coherency of its components.

This course aims to point out the most essential features of

turning in order to help shop engineers and specialists to select

the right tool, adjust machining regime, avoid vibrations, and

improve machining quality. The topics include a tailored

methodology for the selection of indexable cutting inserts and

tool holders (both ISO and ANSI codes are covered), calculating

of the machining regime, and troubleshooting of turning

operations.

2. Drilling

2.1 Basic level

Various studies and surveys indicate that holemaking (drilling)

is one of the most time-consuming metal cutting operations in

the typical shop. It is estimated that 36% of all machine hours

(40% of CNC) are spent performing holemaking operations, as

opposed to 25% for turning and 26% for milling, producing

60% of chips. Therefore, the use of high-performance drills and

reamers could significantly reduce the time required for drilling

operations, and thus reduce holemaking costs.

Over the past decade, the tool materials and coatings used for

drills have improved dramatically. Combined with new

powerful, high-speed-spindles rigid machines, proper tooling

including tool and work holding, and high-pressure high-

concentration coolant supply, these allowed a significant

increase in the cutting speed and penetration rate in drilling

operations. In modern machine shops, as, for example, in the

automotive industry, quality requirement to drilled holes today

are the same as they used to be for reamed holes a decade ago.

Despite all the new developments in drilling, however, there is

still a significant gap in efficiency, quality and reliability of

drilling operation between advanced and common machine

shops. This gap is due to lack of understanding the process and

its surrounding. Therefore, the objective of this course is two-

fold. First, it aims to familiarize application specialists with

properly-defined basic concepts, terminology, and essentials of

drilling. Second, it introduces the concept of the drilling system

formulating the systems rules (laws) and showing the impact of

the first-level system components. The course includes topics on

the selection of application-specific tools, requirements to their

drawings and inspection, tool setting practice, and

troubleshooting of drilling operations.

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2.2 Advanced level

Understanding the drill geometry is a key to improving

efficiency of practically all drilling operations. This general

statement should be extensively elaborated with clear specific

details as no one known to the trainer books, papers, manuals or

any other technical publications/material provides the answer

to an array of simple yet practical questions: Why one needs to

know the drilling tool geometry?”, “What are those parameters

of drilling tool geometry one needs to use in a particular case of

machining”, “To what extent the drilling tool geometry affects

tool life, cutting force, tool wear, integrity of the machined

surface?, “What is effect of the drilling tool geometry on the

accuracy and efficiency of machining operations?” Therefore, a

need is felt to clarify the issues and thus provide practical help

to the practitioners (tool designers, manufacturing/process

engineers) and methodological help to the researches. This is

the main objective of this course.

This course explains classification, geometry and design of

straight flute and twist drills. It argues that the design,

manufacturing and implementation practices of drills are

lagging behind the achievements in the tool materials, powerful,

high-speed-spindles rigid machines and high-pressure MWF

(coolant) supply. Although the wide availability CAD design tool

and CNC precision grinding machines make it possible to

reproduce virtualy any drill geometry, there are not many new

drill designs became available recently. It is stressed that the

prime objective of the drilling system is an increase in the drill

penetration rate, i.e. in drilling productivity as the prime source

for potential cost savings. As the major problem is in

understanding particularities of drill geometry and its

components, this course walks the attenders from simple

concepts starting from the basic terminology in drill design and

geometry to the most complicated concepts in the field keeping

the context to the simplest possible fashion and providing

practical examples. It provides an overview of important results

concerning drill geometry and synthesizes the most relevant

findings in the field with the practice of tool design.

Tool wear

In metal cutting, tool wear is a dominant concern because

process conditions are chosen to give maximum productivity or

economy, often resulting in tool life in minutes. Central to the

problem are: high contact temperatures at the tool–chip and

tool–workpiece interfaces that lead to the softening of tool

material and promote diffusion and chemical (oxidation) wear;

high contact pressures at these interfaces and sliding of freshly

formed (juvenile) surfaces of the work material layers promote

abrasive and adhesion wear; cyclic nature of the chip formation

process which can cause cracking due to thermal fatigue.

Another tool wear mechanism is fretting wear. Fretting is a

small amplitude oscillatory motion, usually tangential, between

two solid surfaces in contact. Fretting wear occurs when

repeated loading and unloading cause cyclic stresses, which

induce surface or subsurface breakup and loss of material.

Vibration is a common cause of fretting wear. The mentioned

wear mechanisms may take place alone or, more frequently, in

combination.

The nature of tool wear, unfortunately, is not yet clear enough in

spite of numerous investigations carried out over the last 50

years. Although various theories have been introduced hitherto

to explain the wear mechanism, the complicity of the processes

in the cutting zone hampers formulation of a sound theory of

cutting tool wear.

The course consists of two parts. The first part aims to

familiarize the attendants with the standard way to

assess/measure/evaluate tool wear in accordance with

ANSI/ASME Tool Life Testing with Single-Point Turning Tools

(B94.55M-1985) Standard. The principal types of tool wear,

classified according to the regions of the tool they affect. Metrics

of too wear and their practical correlation with the work

material type/properties and machining parameters are

discussed with multiple examples carefully tailored for different

types of cutting tools: single-point turning tools, drill and

reamers, milling tools, etc. Wear curves construction and the

concept of tool life are explained.

The second logical part of the course deals with advanced

concepts of cutting tool wear assessment. The concepts of

volumetric/mass tool wear, dimension wear rate, surface wear

rate, etc. will be introduced and explained. The optimal cutting

temperature/cutting speed – the First Metal Cutting Law – will

be introduced and explained with multiple practical examples

related to various machining operations. Practical methods of

determining the optimal cutting temperature/speed are

presented in this part. The concept and practical

implementation of the cutting tool technical resource concludes

the course.

Tool materials

why

Introductio

coating

ongoing activity

th

suggested

titanium alloy, there are more than fifty tool

on the tool market supplied by a

w

Selecting the appropriate cutting tool material for a specific

application is crucial in achieving efficient

operations.

selection of the proper tool material

correlation

this course.

The course discusses various

from high carbon steel to ceramics and diamonds,

today’s metalworking industry. It

differe

differences are, and

of material.

Th

for various application

single material

needed

example increasing hardness generally results in lower

toughness.

The

of the proper

based upon

the

selection governed by material availability and economic

considerations.

50

300 500 700 900 1100

70

90

Temperature, oC

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Carbon Tool Steels

HSS

Carbides

PCD

Ceramics

Tool materials – what, when, how

why

Introduction of newer and better cutting tool materials

coating to cope with the latest high performance materials

ongoing activity in the tool industry. For a given work

there are usually tens or even hundreds choices of tool materials

suggested by various tool suppliers. For instance, in machining

titanium alloy, there are more than fifty tool materials available

on the tool market supplied by a dozen tool manufacturers

worldwide.


application is crucial in achieving efficient

operations. Therefore, machining efficiency is the key in the

selection of the proper tool material. The

correlation between these two notions is the prime

this course.

he course discusses various types of tool material

from high carbon steel to ceramics and diamonds,

today’s metalworking industry. It points out that

differences do exist among tool materials, what these

differences are, and what is the correct application for each type

of material.

The course discusses the properties of the tool materials

for various application. It argues that for a given application, n

single material normally meets all requirements. The properties

needed by cutting tools mean compromise is needed, for


toughness.

The course presents a systematic methodology of the selection

of the proper group of tool materials for a given application

based upon ‘internal’ requirements of this operation in terms of

the required quality and desired process efficiency


considerations.

how, and

newer and better cutting tool materials and

cope with the latest high performance materials is an

work material,

tens or even hundreds choices of tool materials

by various tool suppliers. For instance, in machining

materials available

manufacturers


application is crucial in achieving efficient machining

refore, machining efficiency is the key in the

The establishing

is the prime objective of

tool materials, ranging

from high carbon steel to ceramics and diamonds, used in

points out that significant

, what these

the correct application for each type

materials needed

It argues that for a given application, no

meets all requirements. The properties

by cutting tools mean compromise is needed, for


presents a systematic methodology of the selection

a given application

of this operation in terms of

efficiency. The final


Coolant 1 Basics of application In the current, competitive manufacturing environment, end-users of the coolant are looking to reduce costs and improve productivity. As a result, a closer look at the cost of the coolant was taken. Surprisingly, it was found that the coolant represent a significant part of the manufacturing costs. Just two decades ago, the coolant accounted for less than 3% of the cost of most machining processes. These coolants were so cheap that few machine shops gave them much thought. Times have changed and today the coolant account for up to 15% of a shop production cost, while some European automotive companies reported 17%. The costs of purchase, maintenance and disposal of the coolant are more than two-fold higher than the tool-related costs, although the main attention of researchers, engineers and managers has been focused on the reduction of the cutting tools-related costs. Moreover, coolants, especially those containing oil, have become a huge liability. Not only does the Environmental Protection Agency (EPA) regulate the disposal of such mixtures, but many states and localities also have classified them as hazardous wastes. Therefore, the basic understanding of various aspects of coolant efficiency, rational use, and maintenance is very important to reduce the manufacturing cost and to meet the permissible exposure limit set by the

Occupational Safety and Health Administration (OSHA).

There three equally important pillars of the successful coolant

application: (1) selection of the proper coolant, (2) delivery of

this coolant into point of application, and (3) coolant

maintenance. The proper physical delivery of coolants to the

machining zone is one of the most important aspects of

successful coolant application because, unless coolant is

delivered with the parameters needed and carefully placed, it

cannot perform its functions. Unfortunately, this is still one of

the most neglected aspects of proper coolant application. This is

because the modern books on the subject do not consider this

aspect. This course aims to provide the basic guidelines for the

proper coolant delivery and application.

Two basic aspects of the proper coolant delivery are considered:

1. Delivery of coolant with proper parameters, i.e., velocity,

temperature, etc. This includes the complete hydraulic circuit of

the coolant delivery system with all apparatus (pumps, valves,

filters, control systems, piping, rotating units, internal coolant

channels in spindles and in tool bodies, etc.) 2. Point of application of the coolant which includes the

location and pointing direction of the coolant nozzles and exit

orifices with respect to the tool cutting edge(s) or other

reference components.

Coolant 2 High

a. This aim of the

foundations and detailed explanations of high

application techniques in metal cutting. Covering the external

(single

applications, it

flow rather not its pressure defines the efficiency of high

pre

example, the

considered in the design of hole

high

The costs of maintaining and eventually disposi

combined with the health and safety concerns, have led to a

heightened interest in either eliminating the coolant altogether

or limiting the amount of the coolant applied. The former

process is known as dry machining while the latter is

as near

(MQL) machining. In NDM, an air

fed onto the machining zone. Compared to dry machining, NDM

substantially enhances cutting performance in terms of

incr

parts. Th

NDM methods, discussing their advantages and drawbacks.

Analyzing the available information on the performance of NDM,

a physically

discussed in details. It considers the essential components of the

whole NDM system, arguing that a 360° vision approach is the

key to successful implementation of NDM.

Cryogenic coolants have been used in indus

cold treating applications for quite some time, but their

application in the machining industry as coolants is relatively

new. Cryogenic machining involves the application of a

cryogenic fluid in the machining process, primarily as a co

agent

to perform both conductive and convective cooling of the

machining zone or could be applied indirectly to cool the cutting

tool through conduction alone. The objective of the third pa

the course is to cover the complete area of cryogenic machining

starting from the basics and finishing with application

techniques including the tool designs and cryogenic liquid

delivery systems. Technical and cost efficiency of cryogenic

machining

Coolant 2 - Advanced High-pressure, minimum quantity lubricant (MQL)

.k.a. near dry machining, and cryogenic

This aim of the first part of the course is to presents physic

foundations and detailed explanations of high-pressure


(single-point cutting tools) and internal (drills and reamers)

applications, it explains with multiple examples that

flow rather not its pressure defines the efficiency of high

pressure coolant applications. Using drilling as a simple

example, the first part reveals major issues that should be

considered in the design of hole-making tools with internal

high-pressure coolant supply.

The costs of maintaining and eventually disposing of the coolant,




process is known as dry machining while the latter is

as near-dry machining (NDM) or minimum quantity lubrication

(MQL) machining. In NDM, an air–oil mixture called an aerosol is



increasing tool life and improving the quality of the machined

parts. The second part of the course presents a classification of



a physically attractive explanation of why NDM works is



key to successful implementation of NDM.

Cryogenic coolants have been used in industrial quenching and




cryogenic fluid in the machining process, primarily as a co

agent. This fluid is applied as an external spray through a nozzle



tool through conduction alone. The objective of the third pa





machining are considered with examples.

inimum quantity lubricant (MQL)

ry machining, and cryogenic

part of the course is to presents physic

pressure coolant


point cutting tools) and internal (drills and reamers)

that the coolant

flow rather not its pressure defines the efficiency of high-

drilling as a simple

reveals major issues that should be

making tools with internal

ng of the coolant,




process is known as dry machining while the latter is referred to

dry machining (NDM) or minimum quantity lubrication

oil mixture called an aerosol is



easing tool life and improving the quality of the machined

course presents a classification of



attractive explanation of why NDM works is



trial quenching and




cryogenic fluid in the machining process, primarily as a cooling

. This fluid is applied as an external spray through a nozzle



tool through conduction alone. The objective of the third part of





Design of experiments in metal cutting For centuries, experiments were conducted using OFAT (one-

factor-at-a-time) experimentation method. OFAT

experimentation reached its zenith with the work of Thomas

Edison’s “trial and error” methods. In OFAT, a single variable is

varied at a time, keeping all other variables in the experiment

fixed. The first factor is fixed as a “good” value, the next factor is

examined, and on and on to the last factor. Because each

experimental run considers only one factor, many runs are

needed to obtain sufficient information about the set of

conditions contributing to the problem. This consumes a hefty

amount of time and money, along with running a high risk of

error.

A far more effective method is to apply a systematic approach to

experimentation, one that considers all factors simultaneously.

That approach is called design of experiments (DOE).

A great number of papers, manuals, and books have been

written on the subject in general and as related to

manufacturing in particular. Moreover, a number of special (for

example, Satistica), specialized (for example, Minitab) and

common (for example, MS Excel) computer programs are

available to assist one to carry out DOE with endless examples

available in the Web. Everything seems to be known, the

terminology, procedures, and analyses are well developed.

Therefore, a logical question why this short course is needed

should be answered.

The simple answer is that this course is ‘designed’ from the

experimentalist side of the fence rather than the statistical site

used in vast majority of publication on DOE. As the saying goes

“The grass is always greener on the other side of the fence,” i.e.

“statisticians” often do not see many of real-world problems in

preparing proper tests and collecting relevant data to be

analyzed using DOE.

This course does not cover basic statistics so that a general

knowledge of statistics including probability concept, regression

and correlation analysis, statistical distributions, statistical data

analysis including survey sampling has to be refreshed prior to

attending although it could be covered in the introduction upon

request (two more hours). Rather it presents the overview of

various DOE to be used in manufacturing commenting its

suitability for particular cases. The most common DOE as the

full and fractional factorial including response surface analysis

as well as special DOE as the Taguchi DOE, sieve DOE, split-plot

DOE, and group method of data handling (GMDH) are discussed.

The adequate examples are given.

Finite Element Modeling (FEM) of metal

cutting A number of cutting theories and the FEM models have been

developed to model the metal cutting process in hope to

increase its efficiency and design the proper cutting tools. The

commercial codes MSC.Marc, Deform2D, and Thirdwave

AdvantEdge and others are readily available in the marketplace.

Although many of major manufacturing companies in the

automotive, aerospace, energy, tool industries have one or even

several commercial FEM codes, no one know to the trainer has

made a good use of these codes in the practice of the process

and tool design. The first part of the course aims to explain the

reasons.

The second part of the course explains that to obtain more

information (mechanics, chemistry, etc.) from the FEM an

appropriate about of information should be put in. This is

popularly expressed with the acronym “GIGO,” or “garbage in,

garbage out.” In other words, FEM simulations cannot generate

new knowledge. The results of such simulations are new data

that (provided the data are correct) help in practical operation

and cutting tool design.

The third part of the course answers the most important yet

non-answered question in all FEM simulation of metal cutting,

namely what to do with the result of simulations. Obtaining the

stress, temperature, strain, and other outputs, which are also

often set as the objective of the study or even of simulations,

cannot be considered as the final result because nobody really

knows how to use the data obtained for optimization fo any

practical machining operation and/or design the proper cutting

tool.

This forth part of the course aims to educate the listeners how

to do FEM of metal cutting properly about the concept of

authentication of FEM in metal cutting. This part of the course

concentrates on the fundamental issues with the use of FEM

analysis in metal cutting: the requirement for a physical model,

modeling of the behavior of materials during cutting, and the

verification of the FEM. The discussion of accurate physical

models provides the definition and objective of the metal cutting

system. The discussion of the behavior of materials during

cutting argues that the most common model of behavior, known

as the Johnson and Cook model, is unnecessary

overcomplicated. This forth part emphasizes that the

verification of the FEM is the final and mandatory stage in metal

cutting, with simple physics-based methods of FEM verification

discussed in details.

What does it mean “Metal Cutting”?

Basic equations and correlations used in metal cutting are

known phenomenologically, i.e. from the testing and

implementation practice of various tools. A little is known about

their physical nature. Unfortunately, these experience-based

facts are often incomplete and contradictive as they normally

considered ignoring system properties of the cutting system. As

a result, they cannot provide much guidance in the tool design in

terms of selection the optimal, for a given application, tool

geometry. The theory of metal cutting as taught in student’s

textbooks is of little help as it does not consider correlations

between essential parameters of the cutting tool geometry and

the physics of this process. Only when the physics of the metal

cutting process is understood and the system properties of the

metal cutting system are accounted for, the proper process

parameters and the right cutting tool can be selected. This,

however, can happen if the proper answer a simple question:

What is metal cutting? is known so one can answer to the

following questions:

1. What is the difference between metal cutting and cutting?

2. If a polymer or any other non-metal (wood, stone)

material is cut by means of turning, milling, drilling, etc., what

should this process be called?

3. What kind of cutting is performed by a knife or by a pair

of scissors?

This course aims to provide the answers to these questions

which will surprise many including seasoned professionals in

the field. These answers should help to distinguish metal cutting

among other closely related manufacturing operations revealing

its unique physical features controlled this process. The metal

cutting process is defined as a forming process, which takes

place in the components of the cutting system that are so

arranged that the external energy applied to the cutting system

causes the purposeful fracture of the layer being removed. This

fracture occurs due to the combined stress including the

continuously changing bending stress. The most important

property in metal cutting studies is the system time. The system

time was introduced as a new variable in the analysis of the

metal cutting system and it was conclusively proven that the

relevant properties of the cutting system’s components are time

dependent. The dynamic interactions of these components take

place in the cutting process, causing a cyclic nature of this

process.

The major outcome of the course is that the essence of the metal

cutting process can be understood so the parameters of any

machining operation can then be selected to optimize this

process.

Documents

Training courses that PSMi can offer to the customers Courses.pdf · Training courses that PSMi can offer to the ... ANSI/ASME Tool Life Testing with Single-Point Turning Tools (B94.55M-1985)