study of the effect of cutting parameters on thread profile

7/28/2019 Study of the Effect of Cutting Parameters on Thread Profile

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SELF DECERATION

We hereby declare that

1. The project entitled Study of the Effect of Cutting Parameters on External andInternal Thread Profile submitted by us is an authentic work of our efforts

carried out for the partial fulfillment of the requirements for the award of B.E.

(Mechanical) Degree.

2. The matter embodied in this project work has not been submitted earlier.

3. We will be solely responsible for any form of plagiarism committed out of theproject.

4. The success of information used in our project report have been dulyacknowledged and referenced in our project.

S.NO. Name of Student Roll No. Signature

1 Bal Chand 08 BM 108

2 Masihuzzaman 09 BM 124

3 Utpal Chaterji 07 BM 162

4 Pankaj Kumar 08 BM 129

5 Bikash Chandra Naik 07 BM 110


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ACKNOWLEDGEMENT

We would like to gratefully and sincerely thank Mr. Arshad Noor Siddiquee for his

guidance, understanding, patience, supervision and encouragement throughout the project

work. His mentorship was paramount in providing us a well rounded knowledge and

experience in field of production engineering. He had been very kind and patient while

suggesting us the outlines of this project and correcting our doubts.

We are especially grateful to Prof. Z. A. Khan, Department of Mechanical Engineering,

Jamia Millia Islamia, New Delhi for guiding us in different matters regarding the topic. Inspite of his busy schedule, he helped us a lot in gathering different information, collecting data

and guided us from time to time in completing this project work.

We are thankful to Pump Machine Shop, BHEL, Hyderabad for providing us the facility to

conduct the experiment. The experiment would not have been possible without the facility.

We would like to thankProf. M. Islam, HOD, Department of Mechanical Engineering, Jamia

Millia Islamia for his valuable time and providing facilities in completion of the project work.

Finally, we would like to thank the Jamia Millia Islamia, New Delhi and BHEL, Hyderabad in

particular for providing us with all the facilities needed for our thesis work.

Mr. BAL CHAND

Mr. MASIHUZZAMAN

Mr. UTPAL CHATERJI

Mr. PANKAJ KUMAR

Mr. BIKASH CHANDRA NAIK


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Table of Contents Page No.

2.9 Measuring Instrument 25

2.9.1 Vernier Caliper 25

2.9.2 Dial Test Indicator 262.9.3 Screw Gauge (Micrometer) 262.9.4 Thread Gauges 272.9.5 Optical Comparator 292.9.6 Profilometer 30

Problem Statement 31

Chapter 3: Experimental Setup 32

3.1 Job Material 32

3.2 CNC Lathe 33

3.3 Tools and Tooling 35

3.4 Cutting Fluid 40

3.5 Measurement of Surface Roughness 40

Chapter 4: Experimental Data 42

4.1 CNC Programming for External and Internal Thread Cutting 42

4.2 Experimental Data for External Thread Cutting 46

4.2.1 Data obtained by Changing Spindle Speed. 464.2.2 Data obtained by Changing Cutting Speed 474.2.3 Data obtained by Changing Feed 48

4.3 Experimental Data for Internal Thread Cutting 49

4.3.1 Data obtained by Changing Spindle Speed. 494.3.2 Data obtained by Changing Cutting Speed 50


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5 Table of Contents Page No.4.3.3 Data obtained by Changing Feed 51

Chapter 5: Result and Conclusions 52

Scope for future work 53

References 54


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List of Figures Page No.

Fig. 3.5 Dimensions of Carbide Insert for Thread Cutting 36

Fig. 3.6 Tools for External and Internal Thread Cutting 39

Fig. 3.7 Thread to be cut radially 41

Fig. 3.8 Job moved by 60 clockwise to facilitate stylus movement 41

Fig. 4.1 Graph b/w Spindle Speed & Surface Roughness

for External Thread 46

Fig. 4.2 Graph b/w Cutting Speed & Surface Roughness


Fig. 4.3 Graph b/w Feed Rate & Surface Roughness


Fig. 4.4 Graph b/w Spindle Speed & Surface Roughness

for Internal Thread 49

Fig. 4.5 Graph b/w Cutting Speed & Surface Roughness


Fig. 4.6 Graph b/w Feed Rate & Surface Roughness



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Chapter 2

Literature Review

2.2 Screw Threads

A screw thread, as shown in Fig. 2.2, may be defined as a ridge of uniform cross-

section that follows a helical or spiral path on the outside or inside of a cylindrical

(straight thread) or tapered (conical) surface (tapered thread).

A thread is called a right-hand thread if a nut when turned in clockwise direction screws

on a bolt. Similarly if the nut screws off the bolt when turned in the clockwise

direction, then thread is called left-hand thread.

2.2.1 Nomenclature

Fig. 2.1 Screw Thread


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External Threads: The threads on the outside surface of the bolt, stud and screw etc.,

are called external threads as shown in Fig. 2.2.

Fig. 2.2 External Thread

Internal Threads: The threads on the inside surface of the hole or a nut are called

internal threads as shown in Fig. 2.3.

Fig. 2.3 Internal Thread


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2.2.2 Types of Threads

(i) British Standard Whitworth (B.S.W.) Thread: As shown in Fig. 2.4, it is a

symmetrical Vthread in which the angle between flanks is 55. These threads are

generally used on bolts, nuts and studs etc.

Fig. 2.4 Standard Whitworth (B.S.W.) Thread

(ii) British Association (B.A.) Thread: As shown in Fig. 2.5, it is a symmetrical V

thread in which angle between flanks is 47. These threads are used on screws for

precision work.

Fig. 2.5 British Association (B.A.) thread


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(v) Metric Thread: As shown in Fig. 2.8, these are the threads based on metric system

and the Bureau of Indian Standard has recommended to adopt the unified threads on

metric system.

Fig. 2.8 Metric Thread

(vi) Square Threads: As shown in Fig. 2.9, the sides of the flanks of square threads are

normal to the axis and hence parallel to each other. The pitch of the threads is often

taken as twice that of B.S.W. threads of the same diameter. These are used for power

transmission.

Fig. 2.9 Square Threads


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(vii) Acme Threads: As shown in Fig. 2.10, these are modified form of square threads

and are much stronger than square threads. The threads angle is 29. These are used for

the process of engagement and disengagement of threads e.g., lead screw of lathe,

cocks and bench vices etc.

Fig. 2.10 Acme Threads

(viii) Knuckle Threads: Knuckle threads are the modified form of square threads, as

shown in Fig. 2.11. These are semicircular at the crest and root. The radius of thesemicircle is 0.25 P and working depth is 0.5 P. These threads are used in electric bulb

and bottles etc.

Fig. 2.11 Knuckle Threads


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(ix) Buttress Threads: As shown in Fig. 2.12, these threads are combined form of

square and Vthreads. One side of the thread is perpendicular to the axis of the thread

and other is inclined at 45. These are used for power transmission.

Theoretical Depth, D = P

Actual Depth, d D = 0.75 P

Fig. 2.12 Buttress Threads


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2.2.3 Metric Thread Specifications

A thread specification provides necessary information about the thread for manufacture

or purchase. Threads may be specified in basic or detailed form.

Fig. 2.13(a) shows a basic specification of a Metric thread while Fig. 2.13(b) shows a

detailed specification and the interpretation is given in Table 2.1.

(a) Basic specification ( b) Detail specification

Fig. 2.13 Metric Thread Specifications

Table 2.1 Interpreting Metric Thread Specification

Item Description

1 Metric Thread Identifier

2 Major Diameter (mm)

3 Separator

4 Pitch (mm)5 Major Diameter Tolerance Specification

6 Minor Diameter Tolerance Specification


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2.3 Stainless Steel:

Stainless steel is a generic term for a family of corrosion resistant alloy steels

containing 10.5% or more chromium. All stainless steels have a high resistance to

corrosion. This resistance to attack is due to the naturally occurring chromium-rich

oxide film formed on the surface of the steel. Although extremely thin, this invisible,

inert film is tightly adherent to the metal and extremely protective in a wide range of

corrosive media. The film is rapidly self repairing in the presence of oxygen, and

damage by abrasion, cutting or machining is quickly repaired.

Benefits of Stainless Steel:

Corrosion resistance

All stainless steels have a high resistance to corrosion. Low alloyed grades resist

corrosion in atmospheric conditions; highly alloyed grades can resist corrosion in most

acids, alkaline solutions, and chloride bearing environments, even at elevated

temperatures and pressures.

High and low temperature resistanceSome grades will resist scaling and maintain high strength at very high temperatures,

while others show exceptional toughness at cryogenic temperatures.

Ease of fabrication

The majority of stainless steels can be cut, welded, formed, machined and fabricated

readily.

Strength

The cold work hardening properties of many stainless steels can be used in design to

reduce material thickness and reduce weight and costs. Other stainless steels may be

heat treated to make very high strength components.


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Aesthetic appeal

Stainless steel is available in many surface finishes. It is easily and simply maintained

resulting in a high quality, pleasing appearance.

Hygienic properties

The cleanability of stainless steel makes it the first choice in hospitals, kitchens, food

and pharmaceutical processing facilities.

Life cycle characteristics

Stainless steel is a durable, low maintenance material and is often the least expensive

choice in a life cycle cost comparison.

Types of Stainless Steels:

In addition to chromium, nickel, molybdenum, titanium, niobium and other elements

may also be added to stainless steels in varying quantities to produce a range of

stainless steel grades, each with different properties. There are a number of grades to

chose from, but all stainless steels can be divided into five basic categories:

1. Austenitic2. Ferritic3. Martensitic4. Duplex5. Precipitation hardening

These are named according to the microstructure inherent in each steel group (a

function of the primary alloying elements). Austenitic and ferritic grades account for

approximately 95% of stainless steel applications.


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2.6 Cutting Tool

The tool is wedge shape object of hard material. It is usually made from H.S.S. Beside

H.S.S. machine tool is also made from High Carbon Steel, Satellite, Ceramics,

Diamond, Abrasive, etc. The main requirement of tool material is hardness. It must be

hard enough to resist cutting forces applied on work piece. Hot hardness, wear

resistance, Toughness, Thermal conductivity, & specific heat, coefficient of friction, are

other requirement of tool material. All these properties should be high.

2.6.1 Classification of Cutting Tools

(A) According to number of cutting edge:

1. Single point cutting tool: It is simplest form of cutting tool & it have

only one cutting edge. Examplesshear tools, lathe tools, planer tools, boring tolls etc.

2. Multi point cutting tool: In this two or more single point cutting tools

arranged together as a unit. The rate of machining is more & surface finish is also better

in this case. Example- milling cutter, drills, brooches, grinding wheels, abrasive sticks

etc.

(B) According to motion:

1. Linear motion toolslathe tools, brooches

2. Rotary motion toolsmilling cutters, grinding wheels

3. Linear & rotary motion toolsdrills, taps, etc.


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2.6.2 Single Point Cutting Tool Geometry

Geometry of a single point cutting tool is shown in Fig. 2.16.

Fig. 2.16 Single Point Cutting Tool Geometry

1.6.3 Terminology of Single Point Cutting Tool

1. ShankIt is main body of tool. The shank used to grip in tool holder.

2. FlankThe surface or surface below the adjacent of the cutting edge is called

flank of the tool.

3. FaceIt is top surface of the tool along which the chips slides.

4. BaseIt is actually a bearing surface of the tool when it is held in tool holder or

clamped directly in a tool post.


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5. HeelIt is the intersection of the flank & base of the tool. It is curved portion at

the bottom of the tool.

6. NoseIt is the point where side cutting edge & base cutting edge intersect.

7. Cutting edgeIt is the edge on face of the tool which removes the material

from workpiece. The cutting edges are side cutting edge (major cutting edge) & end

cutting edge ( minor cutting edge).

8. Noise radiusIt provide long life & good surface finish sharp point on nose is

highly stressed, & leaves grooves in the path of cut. Longer nose radius produce

chatter.

9. Tool angles-Tool angles have great importance. The tool with proper angle,

reduce breaking of tool, cut metal more efficiently, generate less heat.

Different angles of a single point cutting tool are as follows:

I. Side cutting edge angle (Cs) (lead angle )

It is the angle between side cutting edge & side of tool flank.

The complementary angle of the side cutting edge is called Approach angle.

With lager side cutting edge angle the chips produced will be thinner & wider which

will distribute the cutting forces & heat produced more over cutting edge.

On other hand greater the component for force tending to separate the work & tool.

This causes chatter.

II. End cutting edge angle (Ce)

This is the angle between end cutting edge & line normal to tool shank.

It satisfactory value is 80 to 150. This is denoted by Ce. Its function is to provide

clearance or relief to trailing end of cutting edge. It prevent rubbing or drag between

machined surface & the trailing port of cutting edge.


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2.7 Cutting Fluids

Cutting fluids, also called lubricants and coolants, are used extensively in machining

processes to achieve the following results:

Reduce friction and wear, thus improving tool life and surface finish.

Reduce forces and energy consumption.

Cool the cutting zone, thus reducing workpiece temperature and thermal

distortion.

Wash away the chips

Protect the machines surface from environmental corrosion.

A cutting fluid may be basically may be a coolant or a lubricant. Its effectiveness in

cutting operation depends on a number factors, such as the method of application,

temperature, cutting speed, and type of machining operation.

The temperature increases as cutting speed increases. Therefore, cooling of the cutting

zone is of major importance at high cutting speeds

Following are the four types of cutting fluids used in machining operations:

(1)Oils(2)Emulsions(3)Semisynthetics(4)synthetics


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(3) Ten-point mean roughness (Rz)

A section of standard length is sampled from the mean line on the roughness chart. The

distance between the peaks and valleys of the sampled line is measured in the y

direction. Then, the average peak is obtained among 5 tallest peaks (Yp), as is the

average valley between 5 lowest valleys(Yv). The sum of these two values is expressed

in micrometer(m).


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2.9 Measuring Instrument

2.9.1 Vernier Caliper

The vernier caliper, as shown in Fig. 2.17, gives a direct reading of the distance

measured with high accuracy and precision. It comprises a calibrated scale with a fixed

jaw, and another jaw, with a pointer, that slides along the scale. The distance between

the jaws is then read in different ways for the three types.

Fig. 2.17 Vernier Caliper

Parts of a vernier caliper:

1. Outside jaws: It is used to measure external diameter or width of an object.2. Inside jaws: It is used to measure internal diameter of an object.3. Depth probe: It is used to measure depths of an object or a hole.4. Main scale: It is the scale marked every mm.5. Main scale: It is the scale marked in inches and fractions.6. Vernier scale: It gives interpolated measurements to 0.1 mm or better.7. Vernier scale: It gives interpolated measurements in fractions of an inch.8. Retainer:It is used to block movable part to allow the easy transferring.
http://en.wikipedia.org/wiki/Accuracy_and_precisionhttp://en.wikipedia.org/wiki/Accuracy_and_precision


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Fig. 2.19 Screw Gauge (Micrometer)

2.9.3 Thread Gauges

A thread pitch gauge, as shown in Fig. 2.20,is used to measure the pitch or lead of

a screw thread. Thread pitch gauges are used as a reference tool in determining the

pitch of a thread that is on a screw or in a tapped hole. This tool is not used as a

precision measuring instrument. This device allows the user to determine the profile of

the given thread and quickly categorize the thread by shape and pitch. This device also

saves time, in that it removes the need for the user to measure and calculate the thread

pitch of the threaded item.

Fig. 2.20 Thread Pitch Gauge


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A Go/NoGo thread gauge refers to an inspection tool used to check thread profile

against its allowed tolerances. Its name derives from its use: the gauge has two tests; the

check involves the threads having to pass one test (Go) and fail the other (No Go).

It is an integral part of the quality process that is used in the manufacturing industry to

ensure interchangeability of parts between processes, or even between different

manufacturers.

A Go/NoGo gauge is a measuring tool that does not return a size in the conventional

sense, but instead returns a state. The state is either acceptable (the part is within

tolerance and may be used) or it is unacceptable (and must be rejected).

Fig. 2.21 shows a Outside Thread Go/NoGo Gauge and Fig. 2.22 shows Inside

Thread Go/NoGo Gauge.

They are well suited for use in the production area of the factory as they require little

skill or interpretation to use effectively and have few, if any, moving parts to be

damaged in the often hostile production environment.

Fig. 2.21 Outside Thread Go/NoGo Gauge

Fig. 2.22 Inside Thread Go/NoGo Gauge


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2.9.5 Optical Comparator

An optical comparator, as shown in Fig. 2.23, is a device that applies the principles of

optics to the inspection of manufactured parts. In a comparator, the magnified silhouette

of a part is projected upon the screen, and the dimensions and geometry of the part are

measured against prescribed limits. The measuring happens in any of several ways. The

simplest way is that graduations on the screen, being superimposed over the silhouette,

allow the viewer to measure, as if a clear ruler were laid over the image. Another way is

that various points on the silhouette are lined up with the retical at the centerpoint of the

screen, one after another, by moving the stage on which the part sits, and a digital read

out reports how far the stage moved to reach those points. Finally, the most

technologically advanced methods involve software that analyzes the image and reports

measurements. The first two methods are the most common; the third is newer and not

as widespread, but its adoption is ongoing in the digital era.

Fig. 2.23 Optical Comparator


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Problem Statement

The main deliverable of our study is the knowledge of the effect of cutting parameters

on thread profile i.e., the effect of the cutting speed and feed on the dimensions of

thread profile. As a part of the project, we have studied the effect of the cutting

parameters by recording different dimensions of thread profile under different values of

cutting speed and feed on stainless steel. Thread cutting on stainless steel using carbide

is the common machining operations in manufacturing industry. When the effect of

cutting parameters is investigated, they can be optimized for efficient cutting.


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Chapter 3

Experimental Setup

3.1 Job Material

The material used for the experiment was Stainless Steel of grade 304 (SAE

designation) or S30400 (UNS designation).

The composition of the material is shown in Table 3.1.

Table 3.1 Composition (by Weight) of Stainless Steel Grade SAE 304

% Cr % Ni % C % Mn % Si % P % S % N

18-20 8-10.5 0.08 2.0 0.75 0.045 0.03 0.1

The geometry of the job is shown in Fig. 3.1.

Fig. 3.1 Drawing of Job


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3.2 CNC Lathe

The HMT L-45 CNC lathe machine was used to perform the thread cutting. The

specifications of the machine are tabulated in Table 3.2 and image of the machine is

given in Fig. 3.2. Turret and control panel are shown in Fig. 3.3.

Fig. 3.2 HMT L-45 CNC Horizontal Lathe

Fig. 3.3 Turret and Control Panel of HMT L-45 CNC Lathe


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Table 3.2 HMT L-45 CNC Horizontal Lathe Specifications

1. Height of centers 450 mm

2. Swing over bed 900 mm

3. Swing over cross slide 470 mm

4. Distance between centers 5000 mm

5. Turret 8 stations

6. Bar passage/Spindle bore 110 mm

7. Spindle power 22 kW

8. Speed Range 4.5 - 450 rpm

9. Rapid traverse 5000 mm/min

10. Tailstock sleeve stroke 300 mm

11. Control system Siemens 840 D


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3.3 Tools and Tooling

FACING & TURNING TOOL

For facing and turning the job to required size, Sandvik carbide insert was used which

are shown in Fig. 3.4. The ISO code of the tool is DCGT070208. The full specification

is given in Table 3.3.

MATERIAL: CARBIDE

ORDERING CODE: SANDVIK DCGT070208

SPECIFICATION: (DCGTO7O2O8)

Table 3.3 Detail of Code for DCGT070208 Carbide Insert

ITEM DESCRIPTION

D Insert shape

C Insert clearance angle (7 Degree)

G Tolerance +/- on class G

T Inser type

07 Insert size or cutting edge length

02 Insert thickness (mm)

08 Nose radius (0.8 mm)

Fig. 3.4 Carbide Inserts for Turning and Facing


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THREADING TOOL

For external thread cutting a single point, SANDVIK R166.0G-16MM01-300,

cutting tool was used. The dimensions of the carbide insert are given in Fig. 3.4.

The full specification of the carbide insert is given below.

MATERIAL: Carbide

TOOL GEOMETRY: Single Point Cutting Tool

PITCH: 3.0 mm

SPECIFICATION: R166.0G-16MM01-300, HA=2.25 & HB=0.42

The details of the carbide insert are as follows:

Fig. 3.5 Dimensions of Carbide Insert for Thread Cutting


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3.4 Cutting Fluid

Machine shops require the use of a coolant which is capable of working in many

applications on a wide variety of metals. Hocut 795-H is a versatile product that can be

used with many machines and metals. It is suitable when machining 300 and 400 series

stainless steel.

Hocut 795-H is compatible with hard water, is clean running and bio-stable, which

assures long, odor-free sump life. It provides corrosion protection without staining and

affords good lubrication for machine ways and indexing mechanisms. Low foaming

characteristics make Hocut 795-H a good choice for high pressure applications.

Under normal conditions, the shelf life for Hocut 795-H is one year.

5 to 10% concentration is used for machining.

The main features of Hocut 795-H is as follows:

Clean running/low foam

Good corrosion protection

Excellent machining capabilities

3.5 Measurement of Surface Roughness

Measurement of surface roughness on thread is done by cutting the job in pieces along

radial direction (i.e., perpendicular to the axis of the longitudinal axis of the job), here

about X-X axis, as shown in Fig. 3.7. Then the parted job is rotated through 60

clockwise, in order to facilitate the movement of stylus as shown in Fig. 3.8.


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Fig. 3.7 Thread to be cut radially

Fig. 3.8 Job moved by 60 clockwise to facilitate stylus movement


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Chapter 4Experimental Data

4.1 CNC Programming for External and Internal Thread Cutting

N05 MSG (TURNING & CHAMFERING)

N10 G0G90G95G18G53D0X1400;

N15 M43

N20 S200 M03;

N22 G96 S350;

N25 T06 D1;

N30 G0G90G54X50Z5M08;

N35 G01X41Z0.2F0.3;

N40 Z-40.0;

N45 X50Z0.2;

N50 X40.0;

N55 Z-40.0;

N60 X50.0 Z0.2;

N65 X36.0 Z0.0;

N70 X39.7 Z-2.0;

N75 Z-40.0;

N80 X50.0;

N85 G0G90G53D0X1400Z5000M09;

N90 M00;


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N95 MSG (FACING)

N100 T02D0;

N115 G0G90G54X50Z2.0;

N120 G0X45.0;

N125 Z-1.0;

N130 X-2.0;

N135 X50.0 Z5.0;

N140 G0G90G53X1400Z5000;

N145 M00;

N150 MSG(EXTERNAL THREADING)

N155 T07D0;

N160 G0G90G54X40Z5.0

N165 G01X40 Z2.0;

N170 CYCLE 97 (3,2,-20,39.7,39.7,2,2,1.3,0.05,30,0,12,3,1,1,0);

N175 G0G90G53X1400Z5000;

N180 M00;

N185 M30;

The detail of the cycle program for external thread cutting is given in Table 4.1.


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Table 4.1 Cycle Programme (External Threads):

TABLE METRIC

As Thread Si MPIT ------------

As Value PIT 3.0

Start Point SPL 2.0

End Point EPL -20.0

Diameter 1 DM1 39.7

Diameter 2 DM2 39.7

Run in Path APP 2.0

Run out Path ROP 2.0

Thread Depth TDEP 1.30

Fin. allow FAL 0.05

Infeed Angle IANG 30.0

Start Pt. offs NSP 0.0

Cuts NRC 12.0

Non cuts NID 3.0

Selection OUTSIDE -----

selection CONST. INFEED -----

No. of Threads NUMT 1.0

Retract VRT 0.0


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4.2 Experimental Data for External Thread Cutting

4.2.1 Data obtained by Changing Spindle Speed at Feed Rate = 0.10 mm/rev

and Cutting Speed = 300 rev/min:

Table 4.3 Data Obtained By Changing Spindle Speed

S.NO SPINDLE

SPEED

(rpm)

THREAD

ANGLE

(degree)

THREAD

DEPTH

(mm)

THREAD

PITCH

(mm)

EXT.

DIA.

(mm)

SURFACE

ROUGHNESS

(m)

1 400 60.0 1.30 3.0 39.7 1.8 Rmax

2 800 59.98 1.30 3.01 39.71 1.2

3 1200 59.96 1.31 2.99 39.71 1.0

4 1500 60.02 1.29 3.02 39.70 0.85

From Table 4.3, it is clear that there are no considerable effects of Spindle Speed on

any other parameter other than surface roughness. Now plotting the graph between

Spindle Speed and surface roughness:

Fig. 4.1 Graph b/w Spindle Speed & Surface Roughness for Ext. Thread

Fig. 4.1 shows the effect of change of Spindle Speed. It shows that as the spindle speed

increases, the surface roughness decreases. It means improved surface finish is

obtained.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.61.8

2

0 500 1000 1500 2000

SurfaceRoughness(Rma

x)

Spindle Speed (rpm)

Graph b/w Spindle Speed & Surface Roughness

SURFACE

ROUGHNESS(Rmax)


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4.2.2 Data obtained by Changing Cutting Speed at Feed Rate = 0.10 mm/rev

and Spindle Speed = 500 rpm:

Table 4.4 Data Obtained By Changing Cutting Speed

S.NO

CUTTINGSPEED

(rev/min)

THREADANGLE

(degree)

THREADDEPTH

(mm)

THREADPITCH

(mm)

EXTERNALDIAMETER

(mm)

SURFACEROUGHNESS

(m)

1 300 60.05 1.30 3.0 39.70 1.95 Rmax

2 400 60.02 1.31 3.01 39.71 1.55

3 500 60.0 1.31 3.01 39.70 1.35

4 600 59.98 1.30 3.00 39.70 0.95

From Table 4.4, it is clear that there are no considerable effects of cutting speed on any

other parameter other than surface roughness. Now plotting the graph between cutting

speed and surface roughness:

Fig. 4.2 Graph b/w Cutting Speed & Surface Roughness for Ext. Thread

Fig. 4.2 shows the effect of cutting speed on surface roughness. It shows that as the

cutting speed increases, the surface roughness decreases. It means improved surface

finish is obtained.

0

0.5

1

1.5

2

2.5

0 200 400 600 800

SurfaceRoughness

(Rmax)

Cutting Speed (m/min)

Graph b/w Cutting Speed & Surface Roughness (Rmax)

SURFACE

ROUGHNESS(Rmax)


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4.2.3 Data obtained by Changing Feed Rate at Cutting Speed = 350 rev/min


Table 4.5 Data Obtained By Changing Feed Rate

S.NO FEEDRATE

(mm/rev)

THREADANGLE

(degree)

THREADDEPTH

(mm)

THREADPITCH

(mm)

EXTERNALDIAMETER

(mm)

SURFACEROUGHNESS

(m)

1 0.10 60.05 1.30 3.01 39.70 1.75Rmax

2 0.15 60.02 1.31 3.01 39.70 1.85

3 0.20 60.05 1.29 3.02 39.7 2.20

4 0.25 60.0 1.29 3.00 38.69 2.80

From Table 4.5, it is clear that there are no considerable effects of feed on any other

parameter other than surface roughness. Now plotting the graph between feed and

surface roughness:

Fig. 4.3 Graph b/w Feed Rate & Surface Roughness for Ext. Thread

Fig. 4.3 shows the effect of feed on surface roughness. It shows that as the feed

increases, the surface roughness increases. It means poor surface finish is obtained.

0

0.5

1

1.5

2

2.5

3

0 0.05 0.1 0.15 0.2 0.25 0.3

SurfaceRoughness(

Rmax)

Feed Rate (rev/min)

Graph b/w Feed Rate & Surface Roughness

SURFACE ROUGHNESS


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4.3 Experimental Data for Internal Thread Cutting

4.3.1 Data obtained by Changing Spindle Speed at Feed Rate = 0.10 mm/rev

and Cutting Speed = 300 rev/min:

Table 4.6 Data Obtained By Changing Spindle SpeedS.NO. SPINDLE

SPEED

(rpm)

THRED

ANGLE

(degree)

THREAD

DEPTH

(mm)

THREAD

PITCH

(mm)

INTERNAL

DIAMETER

(mm)

SURFACE

ROUGHNESS

(m)

1 400 59.97 1.31 2.01 22.7 1.75 Rmax

2 800 59.96 1.30 2.01 22.72 1.35

3 1200 59.97 1.31 1.99 22.70 1.12

4 1500 60.02 1.29 2.02 22.68 0.95

From Table 4.6, it is clear that there are no considerable effects of spindle speed on any

other parameter other than surface roughness. Now plotting the graph between spindle


Fig. 4.4 Graph b/w Spindle Speed & Surface Roughness for Int. Thread

Fig. 4.4 shows the effect of spindle speed on surface roughness. It shows that as the

spindle speed increases, the surface roughness decreases. It means improved surface

finish is obtained.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.61.8

2

0 500 1000 1500 2000

SurfaceRoughness(Rmax

)

Spindle Speed (rpm)

Graph b/w Spindle Speed & Surface Roughness

SURFACE

ROUGHNESS(Rmax)


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4.3.2 Data obtained by Changing Cutting Speed at Feed Rate = 0.10 mm/rev


Table 4.7 Data Obtained By Changing Cutting Speed

S.NO. CUTTINGSPEED

(rev/mm)

THREADANGLE

(degree)

THREADDEPTH

(mm)

THREADPITCH

(mm)

INTERNALDIAMETER

(mm)

SURFACEROUGHNESS

(m)

1 300 60.0 1.30 2.01 22.70 1.85 Rmax

2 400 59.97 1.29 2.00 22.71 1.45

3 500 60.01 1.31 1.99 22.69 1.25

4 600 59.98 1.30 2.00 22.70 1.05

From Table 4.7, it is clear that there are no considerable effects of cutting speed on any

other parameter other than surface roughness. Now plotting the graph between cutting


Fig. 4.5 Graph b/w Cutting Speed & Surface Roughness for Int. Thread

Fig. 4.5 shows the effect of cutting speed on surface roughness. It shows that as the

cutting speed increases, the surface roughness decreases. It means improved surface

finish is obtained.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0 100 200 300 400 500 600 700

SurfaceRoughness(R

max)

Cutting Speed (rev/min)

Graph b/w Cutting Speed & Surface Roughness

SURFACE

ROUGHNESS(Rmax)


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4.2.3 Data obtained by Changing Feed Rate at Cutting Speed = 350 rev/min


Table 4.8 Data Obtained By Changing Feed RateS.NO. FEED

RATE(mm/rev)

THREAD

ANGLE(degree)

THREAD

DEPTH(mm)

THREAD

PITCH(mm)

INTERNAL

DIAMETER(mm)

SURFACE

ROUGHNESS(m)

1 0.10 60.00 1.29 2.00 22.71 1.50 Rmax

2 0.15 60.02 1.30 2.00 22.70 1.85

3 0.20 59.98 1.29 1.99 22.70 2.05

4 0.25 60.0 1.31 1.99 22.69 2.96

From Table 4.8, it is clear that there are no considerable effects of feed on any other

parameter other than surface roughness. Now plotting the graph between feed andsurface roughness:

Fig. 4.6 Graph b/w Feed Rate & Surface Roughness for Int. Thread

Fig. 4.6 shows the effect of feed on surface roughness. It shows that as the feed

increases, the surface roughness increases. It means poor surface finish is obtained.

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1 0.15 0.2 0.25 0.3

SurfaceRoughness(Rmax)

Feed Rate(mm/rev)

Graph b/w Feed Rate & Surface Roughness

SURFACE ROUGHNESS(Rmax)


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Chapter 5: Result and Conclusions

Results for External Thread Cutting:

1) As the spindle speed increases, the surface roughness decreases. It means improvedsurface finish is obtained.

2) As the cutting speed increases, the surface roughness decreases. It means improvedsurface finish is obtained.

3) As the feed increases, the surface roughness increases. It means poor surface finish isobtained.

Results for Internal Thread Cutting:

1) As the spindle speed increases, the surface roughness decreases. It means improvedsurface finish is obtained.

2) As the cutting speed increases, the surface roughness decreases. It means improvedsurface finish is obtained.

3) As the feed increases, the surface roughness increases. It means poor surface finish isobtained.

There are no major effects of cutting parameters on thread pitch, depth, angle and diameter of

external and internal thread. The noticeable effect of thread cutting parameter is on thread

surface roughness of external and internal thread.

When spindle speed and cutting speed are increased separately; keeping other two parameters

constant, the surface roughness is lowered i.e., improved surface finish is achieved for external

and internal thread.

When feed rate is increased keeping other two parameters, the surface roughness also increases

i.e., surface finish gets poorer.


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Scope for future work

Thread cutting on stainless steel using carbide is one among the common and important

machining operations in manufacturing industry. This report concluded that surface

roughness of thread profile is the only parameter which is affected by cutting

parameters. But in our study optimization of cutting parameters is not studied, therefore

in future the optimization of cutting parameters for the optimum value of surface finish

in thread cutting can be investigated. Also, the higher values of cutting speed and feed

can be taken to investigate the surface roughness of threads.


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References

Manufacturing Engineering and Technology

By Serope Kalpakjian and Steven R. Schmid

PRODUCT DATA

HOCUT 795-H

Houghton International Inc.

Single Point Cutting Tool

http://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/

Geometry of Single Point Turning Tools and Drills,

Fundamental and Practical Applications

Astakhov, V.P.

Basic Nomenclature and Definitions for Single - Point

Cutting Tools

ANSI B94.501975

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS

Metric Screw Threads: M Profile

ASME B1.13M-2005

(Revision of ASME B1.13M-2001)

Cutting Tool Geometries

http://mfg.eng.rpi.edu/gmp/pdf/toolgeo.pdf

society of manufacturing engineers

Small part machining,Cutting tools from Sandvik Coromant
http://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/http://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/http://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/http://mfg.eng.rpi.edu/gmp/pdf/toolgeo.pdfhttp://mfg.eng.rpi.edu/gmp/pdf/toolgeo.pdfhttp://mfg.eng.rpi.edu/gmp/pdf/toolgeo.pdfhttp://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/http://www.crazyengineers.com/community/threads/introduction-to-machine-tool-single-point-cutting-tool.46209/


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THREADING

Choosing inserts and tools

Sandvik

Turning Inserts

Korloy Turning Insert Selection

Surface Finish

Abdullah-Al-Mamun

Lecturer, Dept. of IPE

http://teacher.buet.ac.bd/aamamun/Surface%20Finish.pdf

Surface Measurement

http://www.mfg.mtu.edu/cyberman/quality/metrology/surface.html#para2

Basic Structure of a stylus profilometer

By Taylor Hobson Precision

Fitting Identification

Measuring Threads and Seat Angles

By Alfagomma

Stainless Steels

http://www.sudeshnapaul.com/material.science/stainless.html

Surface Finish
http://teacher.buet.ac.bd/aamamun/Surface%20Finish.pdfhttp://teacher.buet.ac.bd/aamamun/Surface%20Finish.pdfhttp://www.mfg.mtu.edu/cyberman/quality/metrology/surface.html#para2http://www.mfg.mtu.edu/cyberman/quality/metrology/surface.html#para2http://www.sudeshnapaul.com/material.science/stainless.htmlhttp://www.sudeshnapaul.com/material.science/stainless.htmlhttp://www.sudeshnapaul.com/material.science/stainless.htmlhttp://www.mfg.mtu.edu/cyberman/quality/metrology/surface.html#para2http://teacher.buet.ac.bd/aamamun/Surface%20Finish.pdf

study of the effect of cutting parameters on thread profile

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