Himanshu choudhary report

JAIPUR ENGINEERING COLLEGE AND RESEARCH CENTRE
JECRC Campus, Shri Ram Ki Nangal, Via-Vatika, Jaipur
LAB MANUAL
Lab Name : PRODUCTIONENGINEERING LAB
Lab Code : 5ME4-23
Branch : MECHANICAL ENGINEERING
Year : III YR (V SEM)
Department of Mechanical Engineering
Jaipur Engineering College and Research Centre, Jaipur
(Affiliated to RTU, Kota)

INDEX
S. No. Contents Page
No.
1 Vision and Mission of the Institute iv
2 Vision and Mission of the Department v
3 Program Educational Objectives (PEOs) vi
4 Program Outcomes (POs) vii
5 PSO of the Department (PSOs) viii
6 RTU Syllabus with List of Experiments ix-x
7 Course Outcomes (COs) xi-xii
8 CO/PO-PSO mapping xiii
9 Introduction about Lab &its Applications xiv
10 Instructions Sheet xv
Experiment List (As per RTU, Kota Syllabus)
Experiment 1
Study of various measuring tools like dial gauge, micrometer, vernier
caliper and telescopic gauges.
Experiment 2 Measurement of angle and width of a V-groove by using bevel
protector.
Experiment 3 (a) To measure a gap by using slip gauges
(b) To compare & access the method of small-bore measurement
with the aid of spheres.
Experiment 4
Measurement of angle by using sine bar.
Experiment 5
(a) Measurement of gear tooth thickness by using gear tooth vernier
caliper.
(b) To check accuracy of gear profile with the help of profile projector.
Experiment 6 To determine the effective diameter of external thread by using three-
wire method.
Experiment 7
To measure flatness and surface defects in the given test piece with the
help of monochromatic check light and optical flat.
Experiment 8
To check the accuracy of a ground, machined and lapped surface - (a)
Flat surface (b) Cylindrical surface.
Experiment 9
Find out Chip reduction co-efficient (reciprocal of chip thickness ratio)
during single point turning.
Experiment
10
Forces measurements during orthogonal turning.

Experiment
11
Torque and Thrust measurement during drilling.
Experiment
12
Forces measurement during plain milling operation.
Experiment
13
Measurement of Chip tool Interface temperature during turning using
thermocouple technique.
Important
Note:
It is mandatory for every student to undertake a Mini project.
Mini project shall be a group activity. A group shall consist of
maximum five students. Final evaluation shall include 30%
weight age to mini project.
Fabrication of an assembly in which parts shall be machined and
standard parts shall be procured.
Content Beyond Syllabus
Experiment 16 Construction & study of tool geometry of single point.
Experiment 17
To measure the surface roughness parameters such as Rz , Ra , Rq and
Rt are measure using Surface roughness tester.

iv
Vision of the Institute
To become a renowned centre of outcome based learning, and work towards academic,
professional, cultural and social enrichment of the lives of individuals and communities.
Mission of the Institute

v
M1: Focus on evaluation of learning outcomes and motivate students to inculcate research
aptitude by project based learning.
M2: Identify, based on informed perception of Indian, regional and global needs, areas of
focus and provide platform to gain knowledge and solutions.
M3: Offer opportunities for interaction between academia and industry.
M4: Develop human potential to its fullest extent so that intellectually capable and
imaginatively gifted leaders can emerge in a range of professions.
Vision of the Department
The Mechanical Engineering Department strives to be recognized globally for outcome based
technical knowledge and to produce quality human resource, who can manage the advance
technologies and contribute to society.
Mission of the Department

vi
M1:To impart quality technical knowledge to the learners to make them globally competitive
mechanical engineers.
M2:To provide the learners ethical guidelines along with excellent academic environment for
a long productive career.
M3: To promote industry-institute relationship.
PROGRAM EDUCATIONAL OBJECTIVES (PEOs)
1. To provide students with the fundamentals of Engineering Sciences with more
emphasis in Mechanical Engineering by way of analyzing and exploiting engineering
challenges.
2. To train students with good scientific and engineering knowledge so as to
comprehend, analyze, design, and create novel products and solutions for the real life
problems.

vii
3. To inculcate professional and ethical attitude, effective communication skills,
teamwork skills, multidisciplinary approach, entrepreneurial thinking and an ability to
relate engineering issues with social issues.
4. To provide students with an academic environment aware of excellence, leadership,
written ethical codes and guidelines, and the self-motivated life-long learning needed
for a successful professional career.
5. To prepare students to excel in Industry and Higher education by Educating Students
along with High moral values and Knowledge.
PROGRAM OUTCOMES (POs)
1. Engineering knowledge: Apply the knowledge of mathematics, science, engineering
fundamentals, and an engineering specialization to the solution of complex engineering
problems.
2. Problem analysis: Identify, formulate, research literature, and analyze complex engineering
problems reaching substantiated conclusions using first principles of mathematics, natural
sciences, and engineering sciences.

viii
3. Design/development of solutions: Design solutions for complex engineering problems and
design system components or processes that meet the specified needs with appropriate
consideration for the public health and safety, and the cultural, societal, and environmental
considerations.
4. Conduct investigations of complex problems: Use research-based knowledge and research
methods including design of experiments, analysis and interpretation of data, and synthesis of
the information to provide valid conclusions.
5. Modern tool usage: Create, select, and apply appropriate techniques, resources, and modern
engineering and IT tools including prediction and modelling to complex engineering activities
with an understanding of the limitations.
6. The engineer and society: Apply reasoning informed by the contextual knowledge to assess
societal, health, safety, legal and cultural issues and the consequent responsibilities relevant to
the professional engineering practice.
7. Environment and sustainability: Understand the impact of the professional engineering
solutions in societal and environmental contexts, and demonstrate the knowledge of, and need
for sustainable development.
8. Ethics: Apply ethical principles and commit to professional ethics and responsibilities and
norms of the engineering practice.
9. Individual and team work: Function effectively as an individual, and as a member or leader
in diverse teams, and in multidisciplinary settings.
10.Communication: Communicate effectively on complex engineering activities with the
engineering community and with society at large, such as, being able to comprehend and write
effective reports and design documentation, make effective presentations, and give and receive
clear instructions.
11. Project management and finance: Demonstrate knowledge and understanding of the
engineering and management principles and apply these to one’s own work, as a member and
leader in a team, to manage projects and in multidisciplinary environments.
12. Life-long learning: Recognize the need for, and have the preparation and ability to engage
in independent and life-long learning in the broadest context of technological change.
PROGRAM SPECIFIC OUTCOMES (PSOs)
PSO1. Apply the knowledge of material science, manufacturing and design to
implement the various concepts of vehicle mechanism.

ix
PSO2. Apply the knowledge of 3D-prininting technology in design and development of
prototypes.
RTU Syllabus with List of Experiments
5ME4-23 : PRODUCTION ENGINEERING LAB
Class:6th
Sem. B. Tech. 3rd
year Evaluation

x
Branch: ME
Credits: 1
Schedule per week: 2 Hrs (Practical)
Examination Time=Three (2) Hours
Maximum Marks = 50
[Internal Assessment/ Sessional(30)& End-
term Exam(20 )]
SN NAME OF EXPERIMENT
1 Study of various measuring tools like dial gauge, micrometer, vernier caliper
and telescopic gauges.
2 Measurement of angle and width of a V-groove by using bevel protector..
3
(c) To measure a gap by using slip gauges
(d) To compare & access the method of small-bore measurement with the aid of
spheres.
4 Measurement of angle by using sine bar.
5
(c) Measurement of gear tooth thickness by using gear tooth vernier caliper.
(d) To check accuracy of gear profile with the help of profile projector.
6 To determine the effective diameter of external thread by using three- wire
method.
7 To measure flatness and surface defects in the given test piece with the help of
monochromatic check light and optical flat.
8 To check the accuracy of a ground, machined and lapped surface - (a) Flat
surface (b) Cylindrical surface.
9 Find out Chip reduction co-efficient (reciprocal of chip thickness ratio) during
single point turning.
10 Forces measurements during orthogonal turning.
11 Torque and Thrust measurement during drilling.
12 Forces measurement during plain milling operation.
13 Measurement of Chip tool Interface temperature during turning using
thermocouple technique.
Important Note:
It is mandatory for every student to undertake a Mini project. Mini project shall
be a group activity. A group shall consist of maximum five students. Final
evaluation shall include 30% weight age to mini project.
 Fabrication of an assembly in which parts shall be machined and
standard parts shall be procured.

xi
Course Outcomes
CO 1: To recognize measuring technique using measuring instruments.
CO 2:To calculate various gear terminology & thread terminology.
CO 3: To determine error and correction factors of different surfaces.
CO 4: To investigate various forces during machining processes.

xii
Mapping of Experimentswith Cos & BT Level
S.
No.
NAME OF EXPERIMENT COs BT*
1. Study of various measuring tools like Dial gauge, Micrometer, Vernier
Caliper and Telescopic Gauges.
CO 1
2. Measurement of angle and width of a V-groove by using Bevel Protector. CO 1
3. (a) To measure a gap by using Slip Gauges
(b) To compare & access the method of small-bore measurement with the aid
of spheres.
CO 1
4. Measurement of angle by using Sine Bar. CO 1
5. (a) Measurement of gear tooth thickness by using Gear Tooth Vernier Caliper.
(b) To check accuracy of gear profile with the help of Profile Projector.
CO 2
6. To determine the effective diameter of external thread by using Three- Wire
method.
CO 2
7. To measure flatness and surface defects in the given test piece with the help of
Monochromatic Check Light and Optical Flat.
CO 3
8. To check the accuracy of a ground, machined and lapped surface.
(a) Flat surface (b) Cylindrical surface.
CO 3
9. Find out Chip reduction co-efficient (Reciprocal of chip thickness ratio)
during single point turning.
CO 4
10. Forces measurements during orthogonal turning. CO 4
11. Torque and Thrust measurement during drilling. CO 4
12. Forces measurement during plain milling operation. CO 4
13. Measurement of Chip Tool Interface temperature during turning using
Thermocouple Technique.
CO 3
* BT - Bloom's Taxonomy
Mapping of Course Outcomes & POs/PSOs

xiii
Engineering
Knowledge
Problem
analysis
Design/Development
of
Solution
Conduct
Invest.
of
complex
problems
Modern
Tool
Usage
The
engineer
and
society
Environment
and
Sustainability
Ethics
Individual
and
Team
Work
Communication
Project
Management
and
Finance
Life-long
Learning
Concepts
of
Vehicle
Mechanism
3-D
printing
Technology
PO
1
PO
2
PO
3
PO
4
PO
5
PO
6
PO
7
PO
8
PO
9
PO
10
PO
11
PO
12
PSO
1
PSO
2
CO-1 3 0 0 0 0 2 0 2 3 2 2 3 0 0
CO-2 3 2 0 1 0 2 0 2 3 2 2 3 0 0
CO-3 3 2 1 0 0 2 0 2 3 2 2 3 0 0
CO-4 3 2 1 2 0 2 1 2 3 2 2 3 0 0
INTRODUCTION ABOUT LABORATORY& APPLICATIONS
Production Engineering is a combination of manufacturing technology with management
science. A production engineer typically has a wide knowledge of engineering practices
and is aware of the management challenges related to production.

xiv
The goal is to accomplish the production process in the smoothest, most-judicious and
most-economic way. Production engineering encompasses the application of castings,
machining processing, joining processes, metal cutting & tool design, metrology, machine
tools, machining systems, automation, jigs and fixtures, die and mould design, material
science, design of automobile parts, and machine designing and manufacturing. In
production Engineering the focus is given on the precision & measurement of instruments
& the minute calculations that are most important part of manufacturing.
Production engineering also overlaps substantially with manufacturing engineering and
industrial engineering.
INSTRUCTIONS SHEET
We need your full support and cooperation for smooth functioning of the lab.
DO’s
 Perform the experimental work precisely as directed by the faculty member/instructor.
 Maintain lab cleanliness.
 Report any damage to equipment or furniture immediately to your faculty
member/instructor.
 Be sure to follow safety protocols while performing experiments with machine tools.
 Shut off equipment after performing the experiment.
 Switch off fan and lights when not in use.
DON’Ts
 Do not enter the laboratory without wearing shoes.
 Do not touch any equipment without prior permission.
 Do not engage in unruly behaviour or boisterous conduct in the laboratory.
 Use of personal audio or video equipment is prohibited in the laboratory.
 Use of cell phones is strictly prohibited.
 Do not change the equipment setting without permission.
BEFORE ENTERINGIN THE LAB
1. All the students are supposed to prepare the theory regarding the next experiment.
2. Students are supposed to bring the practical file and the lab copy.
3. Previous practical should be written in the practical file.
4. Any student not following these instructions will be denied entry in the lab.

xv
WHILE WORKING IN THE LAB
1. Adhere to experimental schedule as instructed by the lab in-charge.
2. Get the previously executed experiment signed by the instructor.
3. Get the output of the current experiment checked by the instructor in the lab copy.
4. Take responsibility of valuable accessories.
5. If anyone is caught carrying any equipment of the lab outside without permission,
they will face strict disciplinary action.

@DEPT. OF MECH. ENGG.,
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Page 25
Experiment No. 1
AIM - Study of various measuring tools like Dial gauge, Micrometer, Vernier Caliper and Telescopic
Gauges
Apparatus required: Dial gauge, Micrometer, Vernier Caliper and Telescopic gauges.
Telescopic feelergauges
These are a range of gauges that are used to measure a bore's size, by transferring the internal dimension
to a remote measuring tool. They are a direct equivalent of inside calipers and require the operator to
develop the correct feel to obtain repeatable results.
The gauges are locked by twisting the knurled end of the handle, this action is performed to exert a
small amount of friction on the telescopic portions of the gauge (the smaller diameter rods found at
the T head of the gauge). Once gently locked to a size slightly larger than the bore, the gauges are
inserted at an angle to the bore and slowly brought to align themselves radially, across the hole. This
action compresses the two anvils where they remain locked at the bores dimension after being
withdrawn.
The gauge is then removed and measured with the aid of a micrometer or caliper.
Small hole gauges
Small hole gauges require a slightly different technique to the telescopic gauges, the small hole gauge is
initially set smaller than the bore to be measured. It is then inserted into the bore and adjusted by
rotating the knurled knob at the base, until light pressure is felt when the gauge is slightly moved in the
bore. The gauge is then removed and measured with a caliper or micrometer

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Page 26
Small hole gauge set. Sizes from top to bottom:
3 to 5 mm (0.118 to 0.197 in)
5 to 7.5 mm (0.197 to 0.295 in)
7.5 to 10 mm (0.295 to 0.394 in)
10 to 13 mm (0.394 to 0.512 in)

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1. Vernier scales
Most common measuring instruments have a simple scale. For example in using a ruler, the ruler is
placed next to the item being measured and the mark closest to the end of the item is recorded. If we
want increased precision, we use a ruler with finer divisions on the scale, that is a smaller instrument
least count. This is suggested in Figure 1.
The ability to use high precision scales is limited by the spacing between the marks. Thus it is easy to
have a least count of 1 mm, more difficult to have a least count of 0.2 mm, and virtually impossible to
have a least count of 0.002 mm (a human hair has a diameter of about 0.050 mm.) In order to increase
precision we need an auxiliary scale called a vernier scale. The vernier scale subdivides the least count
from the main scale into 10, 50 or 100 subdivisions. Vernier scales are found on a wide range of
instruments. In Section 2 we will discuss the vernier caliper.
Any instrument that uses a vernier will have two scales, a main scale and a vernier scale as is seen in
Figure 2. A measurement is made by combining the readings from the two scales.
The main scale works just like a ruler: the 0-mark on the vernier is compared to a main scale and the
result is written down. Use the mark next to the zero, not the mark next to the edge of the vernier. Be
sure to record the value of the main scale mark that is just to the left of the vernier zero mark as is
shown in the above diagram. That is, record the value of 3.3 cm rather than 3.4 cm, even though the
answer is closer to 3.4 cm.

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Page 28
Now look closely at the vernier scale in Figure 2. Notice that 10 divisions on the vernier match 9
divisions on the main scale. This guarantees that one of the vernier markings will line up exactly with a
mark on the main scale. Decide which vernier mark comes closest to matching a main scale mark, in our
example this is vernier mark 8. Combine the two readings to give the final length of 3.38 cm.
Common mistakes:
 Do not try to read the main scale at the point where the lines match best. This has no meaning.
Read from the location of the 0 on the vernier scale instead.
 Sometimes it is difficult to tell whether the best match of lines is for vernier marks 9, 0, or 1.
Make your best estimate, but realize that the final result including the vernier must round off to
the result you would choose if there was no vernier. If the mark is close to 3.20 on the main
scale, but the vernier reading is 9, the length is 3.19 cm. If the mark is close to 3.2 on the main
scale and the vernier is 1, the length is 3.21 cm.
A good way to learn about reading verniers is to use Fu-Kwun Hwang's Java Applet . When you go to
this site, click in the check box next to "show". Then drag the movable scale with the mouse. A red
arrows will show the reading on the main scale and the reading on the vernier, and the final reading is
shown on the arrow separating the jaws of the caliper. Once you get the hang of reading the vernier
caliper, try unchecking the "show" box, moving the jaw, making a reading, and checking your reading
by checking the "show" box.
Figure shows a common use for a vernier called a vernier caliper. This caliper can measure the outside
diameter of an object (outside vernier), the inside diameter of a hole (inside caliper), or the depth of a
hole (depth probe). The figure includes directions on the use of the vernier caliper.
We will most often measure outside diameters. One jaw of the caliper is fixed, and the other jaw moves
and is connected to the vernier.
1. Check that the vernier caliper correctly reads zero when the jaws are closed. (if not, check with
the lab instructor.)
2. Close the jaws around the object but do not over tighten. The jaws should exert a firm pressure
on the object.

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Page 29
3. When both locking screws are tightened the caliper can be removed from the object and read
without worrying if the jaws will shift position.
a. You can read the main scale to the nearest tenth of a centimeter.
b. The vernier consists of 50 divisions, meaning that 0.1 cm is divided into 50 parts and the
final least count is 0.1 cm/50 = 0.002 cm = 1/50 mm. Read the vernier as described in the
previous section, with a result like 1.4 or 1.6 or 2.0. A reading of 1.6 from the vernier
really means 0.016 cm which is added to the main scale reading to give the final
diameter
Micrometer
The micrometer is a precision measuring instrument, used by engineers. Each revolution of the rachet
moves the spindle face 0.5mm towards the anvil face. The object to be measured is placed between the
anvil face and the spindle face. The rachet is turned clockwise until the object is ‘trapped’ between these
two surfaces and the rachet makes a ‘clicking’ noise. This means that the rachet cannot be tightened any
more and the measurement can be read.
Basic Principle
Micrometers use the principle of a screw to amplify small distances (that are too small to measure
directly) into large rotations of the screw that are big enough to read from a scale. The accuracy of a
micrometer derives from the accuracy of the thread-forms that are central to the core of its design. In
some cases it is a differential screw. The basic operating principles of a micrometer are as follows:
1. The amount of rotation of an accurately made screw can be directly and precisely correlated to a
certain amount of axial movement (and vice versa), through the constant known as the
screw's lead. A screw's lead is the distance it moves forward axially with one complete turn
(360°). (In most threads [that is, in all single-start threads], lead and pitch refer to essentially the
same concept.)
2. With an appropriate lead and major diameter of the screw, a given amount of axial movement
will be amplified in the resulting circumferential movement.

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Page 30
Least count of micrometer
formula: Least Count (L. C) = Pitch/no. of divisions on micrometer barrel(thimble)
where,Pitch = distance travelled by thimble on linear scale in one rotation
How to read a micrometer
1. Read the scale on the sleeve. The example clearly shows12 mm divisions.
2. Still reading the scale on the sleeve, a further ½ mm (0.5) measurement can be seen on the bottom
half of the scale. The measurement now reads 12.5mm.
3. Finally, the thimble scale shows 16 full divisions (these are hundredths of a mm).
The final measurement is 12.5mm + 0.16mm = 12.66

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Page 31
Dial Gauge (Dial Indicator)
An indicatoris any of various instruments used to accurately measure small distances and angles,
and amplify them to make them more obvious.The different component of dial gauge indicator is shown
in fig. It consist of plunger, removable contact pt, stem a transparent glass cover, calibrated dial pointer,
bezel camp or bezel locking nut. Revolution counter in order to counter in order to count the no of
revolution of a pointer, dust proof cap etc.
Least count of Dial Gauge =
= 1/100 = 0.01mm

EGSPEC
Page 32
Reading from Dial gauge
TSR = MSR + SD x LC
Where:- TSR= total scale reading
MSR= main scale reading
SD = Scale division
RESULT: We have made the study of the above measuring tools.
VIVA QUESTIONS
1. What is the least count of vernier calliper?
2. What is the least count of dial gauge?
3. What is telescopic gauge?
4. What is the least count of micrometer?
5. Give applications of dial gauge. ?
6. What is the principle behind the vernier calliper?
7. What are the upper jaws used for?
8. What is the use of ratchet stop in micrometer?

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Page 33

EGSPEC
Page 34
Experiment No. 2
AIM - Measurement of angle and width of a V-groove by using bevel protector.
Apparatus required: Universal bevel protractor with accessories
THEORY: The bevel protractor is used to measure the various angles of both small and large
components with accuracy up to 5 minutes. The design of the universal bevel protractor type had
considerably increased the scope of angular measurement with the adjustable blades and the protractor
can be indexed through 3600. The same basic principle as in the other vernier scales was used in this
instrument.
CONSTRUCTIONAL DETAILS & APPLICATIONS:
LEAST COUNT: The vernier scale of the protractor had 24 equal divisions with 12divisions on each
side of zero. On each side 12 divisions are marked from 0-60 and occupying 23 divisions on the main
scale. Each division on vernier scale measures 23/12o.Therefore least count is the difference between
one main scale division and one vernier scale division [2o – 23/12o= 1/12o = 5’] Once the least count
was known the method of taking the reading is as usual.
PROCEDURE:

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Page 35
1. The appropriate size blade to suit the given job was fixed and locked.
2. The job / component was placed by touching the reference face and the movable blade.
3. The blade was locked after ensuring the proper contact on the two faces of the job.
4. The reading was noted down corresponding to the zero of the vernier scale.
(M.S.R + V.S.C x 1/12)
5. The procedure was repeated to find out all the required angles.
PRECAUTIONS:
1. The blades should be fined tightly without any play.
2. Blade should be clamped only after ensuring the contact of the blade over the entire length of the
component.
3. The instrument should be cleaned before and after use.
4. Vernier coincidence should be taken without parallax error

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Page 36
OBSERVATIONS:
SPECIMEN – 1:
1=
2=
3=
SPECIMEN – 2:
1=
2=
3 =
RESULT:
The angles of the various corners of the given specimen were found to be as follows.
s1=
s2=
RESULT: Angle of V-grove …..and width ….. are measured.
VIVA QUESTIONS
Q1. What is the least count of bevel protector?

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Page 37
Q2. What are the practical applications of bevel protector?
Q3. What is combination set?
Q4. Name the various parts of bevel protector.
Q5. What is the difference betweenbevel protectorandcombinationset?
Q6. What is the range of bevel protractor?
Q7. Upto which value optical bevel protractor can take the readings?
Q8. Which of the following are the types of mechanical bevel protractor?
Q9. What is the parallel limit of blade of optical bevel protractor?
Q10. Which of the following is not true for type D mechanical bevel protractor?

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Page 38
EXPERIMENT NO 3(A)
AIM- To measure a gap by using slip gauges
Apparatus required: Slip Gauge or Gage blocks Measuring Instruments
Slip gauges - gage blocks - Johansson gauges
Slip gauges (also known as Gage blocks, Johansson gauges) are precision ground and lapped
measuring standards. They are used as references for the setting of measuring equipment such as
micrometers, gap gauges, sine bars, dial indicators (when used in an inspection role).
Slip gauges Grades:
They are available in various grades depending on their intended use.
 Calibration (AA) - (tolerance +0.00010 mm to -0.00005 mm)
 Reference (AAA) -high tolerance (± 0.00005 mm or 0.000002 in)

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 Inspection (A) - (tolerance +0.00015 mm to -0.00005 mm)
 workshop (B) - low tolerance (tolerance +0.00025 mm to -0.00015mm
Slip gauges are wrung together to give a stack of the required dimension. In order to achieve the
maximum accuracy the following precautions must be preserved.
- Use the minimum number of blocks.
- Wipe the measuring faces clean using soft clean chamois leather.
- Wring the individual blocks together.
Description:
Each gauge block consists of a block of metal or ceramic with two opposing faces ground precisely flat
and parallel, a precise distance apart. Standard grade blocks are made of a hardened steel alloy, while
calibration grade blocks are often made of tungsten carbide or chromium carbide because it is harder
and wears less. Gauge blocks come in sets of blocks of various lengths, along with two wear blocks, to
allow a wide variety of standard lengths to be made up by stacking them. The length of each block is
actually slightly shorter than the nominal length stamped on it, because the stamped length includes the
length of one wring film, a film of lubricant which separates adjacent block faces in normal use. This
nominal length is known as the interferometry length.
In use, the blocks are removed from the set, cleaned of their protective coating (petroleum jelly or oil)
and wrung together to form a stack of the required dimension, with the minimum number of blocks.
Gauge blocks are calibrated to be accurate at 68 °F (20 °C) and should be kept at this temperature when
taking measurements. This mitigates the effects of thermal expansion. The wear blocks, made of a
harder substance like tungsten carbide, are included at each end of the stack, whenever possible, to
protect the gauge blocks from being damaged in use.
Gauge Block Metric Set
WRINGING

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Page 40
Wringing is the process of sliding two blocks together so that their faces lightly bond. Because of their
ultra flat surfaces, when wrung, gauge blocks adhere to each other tightly. Properly wrung blocks may
withstand a 75 lbf (330 N) pull. While the exact mechanism that causes wringing is unknown, it is
believed to be a combination of
 Air pressure applies pressure between the blocks because the air is squeezed out of the joint.
 Surface tension from oil and water vapor that is present between the blocks.
 Molecular attraction occurs when two very flat surfaces are brought into contact. This force
causes gauge blocks to adhere even without surface lubricants, and in a vacuum.
It is believed that the last two sources are the most significant.
There is no magnetism involved, although to a user the clinging together of the blocks feels a bit like a
weak refrigerator magnet's clinging to another. Unlike with magnets, however, the cling only lasts while
the blocks are completely joined—the blocks do not attract each other across any visible gap, as
magnets would.
The process of wringing involves four steps:
1. Wiping a clean gauge block across an oiled pad (see the accessories section).
2. Wiping any extra oil off the gauge block using a dry pad (see the accessories section).
3. The block is then slid perpendicularly across the other block while applying moderate pressure
until they form cruciform.
4. Finally, the block is rotated until it is in line with the other block.
After use the blocks are re-oiled or greased to protect against corrosion. The ability for a given
gauge block to wring is called wringability; it is officially defined as "the ability of two surfaces to
adhere tightly to each other in the absence of external means." The minimum conditions for
wringability are a surface finish of 1 microinch (0.025 µm) AA or better, and a flatness of at least
5 µin (0.13 µm).
There is a formal test to measure wringability. First, the block is prepared for wringing using the
standard process. The block is then slid across a 2 in (51 mm) reference grade (1 µin (0.025 µm)
flatness) quartz optical flat while applying moderate pressure. Then, the bottom of the gauge block

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is observed (through the optical flat) for oil or color. For Federal Grades 0.5, 1, and 2 and ISO
grades K, 00, and 0 no oil or color should be visible under the gauge block. For Federal Grade 3 and
ISO grades 1 and 2, no more than 20% of the surface area should show oil or color. Note that this
test is hard to perform on gauge blocks thinner than 0.1 in (2.5 mm) because they tend not to be flat
in the relaxed state.
General Usage Guidance
 The measuring faces, gauge body and parts should be free from scratches, chips, burrs, discoloration,
peeling, rust, sward and other debris. Even if this does not affect the measurement it could scratch the
part or gauge and make them unusable.
 After being used the gauge should be wiped clean with a dry cloth removing any oil, cutting fluid,
fingerprints etc. If left for a period of time, these may cause the gauge to corrode.
 Great care should be taken to ensure gauges are not bent or damaged. If measurement equipment is
damaged or worn it must be replaced or sent for calibration immediately.
 Care should be taken to ensure that the gauge is correctly aligned with the feature.
 Figure 7 shows the importance of both position and perpendicularity when measuring a diameter.

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 Gradations can vary greatly between similar gauges and care should be taken not to misread scales.
Even if the scale is correctly interpreted parallax error and Abe error can cause inaccuracies. The scale
should be read from a viewpoint perpendicular to the scale’s axis and the jaws or anvils should never be
over tightened to avoid this.
 Gauges should be handled with care to minimize heat transfer and prevent damage. Heat transferred
from operators’ hands to measurement surfaces can cause measurement errors and touching probes or
automated devices can cause serious damage.
 Gauges and fixtures should be checked for excessive play prior to use.
 Wherever possible, measurement equipment should be cleaned in accordance with the manufacturer’s
recommendations
RESULT: The measured gap of a given work piece is…….
VIVA QUESTION
Q1. What is slip gauge?
Q2. How the wringing is done between slip gauges.
Q3.why wringing is done between slip gauges
Q4. What precautions may be followed during use of slip gauges?
Q5. What do you mean by slip gauge grades?
Q6. What is the value of hardness for slip gauge accessories?
Q7. What is the value of flatness for the surface upon which slip gauges are wrung?
Q8. What are the slip gauge accessories?
Q9. What is the approximate size of slip gauges?
Q10. Define Error.
EXPERIMENT NO 3(B)

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AIM - To compare & access the method of small-bore measurement with the aid of spheres.
Three equal balls are spaced evenly within the bore, and a fourth ball, which need
not be of the same size as the three others, is placed upon them.
The balls rest on a plane surface without having hollows in which one or more balls may
rest. Referring to Fig, height H is measured and from this, with diameter of the balls, the
diameter of the ring is easily determined. Thus, in the triangle ABC shown in Fig.
The size of the balls is so chosen that the angle 9 in Fig is between 30 and 60 degree.
If this angle is large, small errors in measuring H will result in large errors in the diameter
determined, and if it is small, heavy contact force between the balls will reduce the accuracy of the
result. Readings are taken at both ends of the bore and at positions in between by standing the
balls on three equal rollers placed with their axis vertical.
Fig. Measurement of bore diameter.
This method can be applied to obtain the diameter of a recessed hole although in such cases the
diameter may not be required to a very fine degree of accuracy and the simpler method shown in Fig.
2.152 is satisfactory. Referring to this figure, the dimension T is given by

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Viva Questions
Q1. Why we use the balls to measure the dia. of hole?
Q2. How many balls are used to measure the dia. of holes?
Q3. What should be the dia. of balls to measure hole dia.?
Q4. What is the minimum dia. of bore that can be measured using the balls?
Q5. What are the practical applications of this method?
Q6. What is accuracy?
Q7. Give any four methods of measurement
Q8. What is the basic Principle of measurement?
Q9. Define True size.
Q10. How to use the dial bore gauge?

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EXPERIMENT NO-04
Aim: Measurement of angle by using sine bar.
Apparatus required: Sine Bar and slip gauges.
Theory: A sine bar consists of a hardened, precision ground body with two precision ground cylinders
fixed at the ends. The distance between the centers of the cylinders is precisely controlled, and the top
of the bar is parallel to a line through the centers of the two rollers. The dimension between the two
rollers is chosen to be a whole number (for ease of later calculations) and forms the hypotenuse of a
triangle when in use.
When a sine bar is placed on a level surface the top edge will be parallel to that surface. If one roller is
raised by a known distance, usually using gauge blocks, then the top edge of the bar will be tilted by the
same amount forming an angle that may be calculated by the application of the sine rule.
 The hypotenuse is a constant dimension—(100 mm or 10 inches in the examples shown).
 The height is obtained from the dimension between the bottom of one roller and the table's
surface.
 The angle is calculated by using the sine rule. Some engineering and metalworking reference
books contain tables showing the dimension required to obtain an angle from 0-90 degrees,
incremented by 1 minute intervals.
Angles may be measured or set with this tool.

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10-inch and 100-millimetre sine bars. In the U.S., 5-inch sine bars are the most common size.
Angles are measured using a sine bar with the help of gauge blocks and a dial gauge or a spirit level.
The aim of a measurement is to measure the surface on which the dial gauge or spirit level is placed
horizontally. For example, to measure the angle of a wedge, the wedge is placed on a horizontal table.
The sine bar is placed over the inclined surface of the wedge. At this position, the top surface of the sine
bar is inclined the same amount as the wedge. Using gauge blocks, the top surface is made horizontal.
The sine of the angle of inclination of the wedge is the ratio of the height of the gauge blocks used and
the distance between the centers of the cylinders.
NOTE:
 Proof of any angle can be traced to
 dividing the circle
 the sine principle
 Sine principle uses the ratio of two sides of a right triangle in deriving a given angle
 any scale may be employed, as the ratio of the sides is used
 Dividing the circle is based upon the fact that the circle can be divided into any equal number of
parts
 The accuracy of the circular division is proven when the circle is closed.
MEASURING INSTRUMENTS & TOOLS:
1. Sine bar (Specification: )
2. Dial gauge
3. Dial gauge stand
4. Slip gauge set
5. Surface plate
THEORY & PRINCIPLE: The high degree of precision available for linear measurement in the form
of slip gauges can be utilized for the measurement of angles with the aid of a very simple and best
measuring tool known as sine bar. The principle involved in this measurement was that the sine bar, slip
gauges and the datum surface i.e. surface plate on which they lay form a right-angled triangle. The sine

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bar forms as hypotenuse of the right angled triangle and the slip gauges form the side opposite to the
required angle. If θ is the angle to be measured and if H is the height of slip gauge and L is the length of
the sine bar, from the right-angled triangle.
Sinθ = L/H
PROCEDURE:
1. The surface plate was considered as the datum to conduct the experiment.
2. The component whose angle is to be checked was mounted securely on the sine bar and both
are placed on the surface plate.
3. The sine bar along with the component was set at an approximate angle by placing a known
size of slip gauge at one end of the sine bar, so that the tapered side of the component is made
parallel to the surface plate.
4. The dial gauge mounted on a suitable stand was placed adjacent to the sine bar so that the plunger
just slides on the surface of the component. At one end the dial gauge was adjusted to read zero.
5. The same dial gauge was placed at the other end of the component and the reading is noted.
6. The height of slip gauges under the sine bar was adjusted until the dial gauge read zero at both ends
of the component and the corresponding slip gauge size was noted down.
7. The acute angle made by the sine bar with the surface plate is the taper angle of the Component.
PRECAUTIONS:
1. The surface plate, slip gauge set and sine bar should be degreased properly.
2. The dial gauge should be clamped to the stand properly so that the plunger is vertical to the
base.
3. The dial gauge plunger should be handled gently and the gauge was set to zero after giving
slight initial compression to the plunger.
4. The slip gauges should be placed gently under the roller of the sine bar.
Observations and calculations:
Length of the sine bar = L mm

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Height of the slip gauges = H mm
RESULT:
Taper angle of the specimen =
VIVA QUESTION
Q1. What is sine bar?
Q2. Why the holes is provided in sine bar
Q3. What is the standard size of sine bar?
Q4. How the internal tapers are measured using sine bar
Q5. What is the maximum angle that can be measured by sine bar?
Q6. What are the modifications of Sine Bar?
Q7. What is the principle of Sine Bar?
Q8. What is a sine center?
Q9. What are the sources of errors in Sine Bar?
Q10. What are the limitations of Sine Bar?

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Experiment-05(A)
AIM- Measurement of gear tooth thickness by using gear tooth vernier caliper
APPARATUS REQUIRED
1. Gear tooth Vernier,
2. Gear specimen.
SPECIFICATION
Gear tooth Vernier: Range: Horizontal = 0-40 mm Least count = 0.02 mm
Vertical = 0-20 mm
Where,
W = Chordal width of tooth in mm
m = Module of gear in mm
D = Chordal addendum of gear in mm
T = No. of teeth
d = Outside diameter of gear in mm
Theory:
GEAR TOOTH VERNIER
The tooth thickness is defined as the length of the arc of the pitch circle between opposite faces of the
same tooth. Most of the time a gear vernier is used to determine the tooth thickness. As the tooth
thickness varies from top to bottom, any instrument for measuring on a single tooth must
1. Measure the tooth thickness at a specified position on the tooth.
2. Fix that position at which the measurement is taken.

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The gear tooth vernier, therefore, consists of a vernier caliper for making the measurement M, combined
with a vernier depth for setting the dimension h at which the measurement M is to be affected.
Fig. Gear tooth vernier caliper
Fig. Gear tooth thickness at pitch line

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TERMINOLOGY OF SPUR GEAR
Fig. Spur gear
Pitch surface: The surface of the imaginary rolling cylinder (cone, etc.) that the toothed gear may be
considered to replace.
Pitch circle: A right section of the pitch surface.
Addendum circle: A circle bounding the ends of the teeth, in a right section of the gear.
Root (or dedendum) circle: The circle bounding the spaces between the teeth, in a right section of the
gear.
Addendum: The radial distance between the pitch circle and the addendum circle.
Dedendum: The radial distance between the pitch circle and the root circle.
Clearance: The difference between the dedendum of one gear and the addendum of the mating gear.
Face of a tooth: That part of the tooth surface lying outside the pitch surface.
Flank of a tooth: The part of the tooth surface lying inside the pitch surface.
Circular thickness: (also called the tooth thickness) The thickness of the tooth measured on the pitch
circle. It is the length of an arc and not the length of a straight line.
Tooth space: The distance between adjacent teeth measured on the pitch circle.
Backlash: The difference between the circle thickness of one gear and the tooth space of the mating
gear.
Circular pitch,p: The width of a tooth and a space, measured on the pitch circle.

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Diametral pitch P: The number of teeth of a gear per inch of its pitch diameter. A toothed gear must
have an integral number of teeth. The circular pitch, therefore, equals the pitch circumference divided
by the number of teeth. The diametral pitch is, by definition, the number of teeth divided by the pitch
diameter.
Module m: Pitch diameter divided by number of teeth. The pitch diameter is usually
specified in inches or millimeters; in the former case the module is the inverse of diametral pitch.
Fillet : The small radius that connects the profile of a tooth to the root circle.
Pinion: The smaller of any pair of mating gears. The larger of the pair is called simply the gear.
Velocity ratio: The ratio of the number of revolutions of the driving (or input) gear to the
number of revolutions of the driven (or output) gear, in a unit of time.
Pitch point: The point of tangency of the pitch circles of a pair of mating gears.
Common tangent: The line tangent to the pitch circle at the pitch point.
Line of action: A line normal to a pair of mating tooth profiles at their point of contact.
Path of contact: The path traced by the contact point of a pair of tooth profiles.
Pressure angle : The angle between the common normal at the point of tooth contact and the common
tangent to the pitch circles. It is also the angle between the line of action and the common tangent.
Base circle : An imaginary circle used in involute gearing to generate the involutes that form the tooth
profiles.
PROCEDURE
1. The T, d of the given gear block are measured.
2. The module m‘ it then calculated.
3. Theoretical values of ‗W‘ and ‘D‘ are computed.
4. Theoretical values of ‗W‘ are set in horizontal Vernier scale of gear tooth Vernier and corresponding
actual ‗D‘ value scale.
5. Theoretical values of ‗D‘ is set and ‗W‘ is measured along Horizontal scale.
6. This procedure is repeated for 5 teeth and value tabulated.
OBSERVATION:

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1. Least count of caliper= 0.02mm
2. Number of teeth= 40
TABLE FOR SETTING GEAR TOOTH CALLIPER FOR SPUR GEAR
NO. OF
TEETH
30 32 34 36 38 40 42
CHORDAL
THICKNESS
1.5700 1.5701 1.5702 1.5703 1.5703 1.5704 1.5704
HEIGHT OF
TOOTH
1.0206 1.0192 1.0182 1.0171 1.0162 1.0154 1.0146
CHORDAL THICKNESS:
S
NO
M.S.R V.S.R CHORDALTHICKNESS
(M.S.R+V.S.R*L.C)
VERIFICATION
(DIGITAL VERNIER
CALIPER)
1 4 8 4 + 8*0.02 = 4.16 4.49
2 4 9 4 + 9*0.02 = 4.18 4.32
HEIGHT OF THE TOOTH:
S
NO
M.S.R V.S.R CHORDAL
THICKNESS
(M.S.R+V.S.R*L.C)
VERIFICATION
(DIGITAL
VERNIER
CALIPER)
1 4 7 4 + 7*0.02 = 4.14 4.26
2 4 6 4 + 6*0.02 =4.12 4.10
CALCULATIONS:
1. Pitch circle diameter, D=(TxOD)/(T+2)=
2. module, m=D/T mm=

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3. Addendum=m=
4. Dedendum=m+0.157m=
Result:: We have measured gear tooth thickness and various gear parameters of a gear using vernier
gear tooth caliper.
Viva Questions
Q1. Why we use the balls to measure the dia. of hole?
Q2. How many balls are used to measure the dia. of holes?
Q3. What should be the dia. of balls to measure hole dia.?
Q4. What is the minimum dia. of bore that can be measured using the balls?
Q5. What are the practical applications of this method?
Q6. Define – Backlash.
Q7. Define – Module.
Q8. Define – Backlash.
Q9. Define – Pitch Circle diameter
Q10. Define – face width

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Experiment-05(B)
AIM- To check accuracy of gear profile with the help of profile projector.

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APPARATUS REQUIRED
1. Contour projector
2. Work holding centre
SPECIFICATION
Contour projector magnification accuracy = ±0.1%
Micrometer Head = 0-25 mm
Least Count = 0.1 mm
Colour illuminator = 150/250 W Halogen
Magnification = 10x, 20x, 50x lenses
PARTS TO BE MEASURED
PROCEDURE
1. The required Magnification adapter is fixed in the center projector.
2. The flat specimen is placed on the glass plate and perfect ly focused on the screen.
3. The profile of specimen is traced on a tracing paper is fixed on the screen using pencil.
4. Then the angle between the two reference surface and dimension are measured using table
micrometer and the Rota table screen circular scale and are tabulated
PROFILE PROJECTOR
A profile projector is also referred to as an optical comparator, or even known as a shadowgraph, a
profile projector is an optical instrument utilized for measuring. The projector magnifies the profile of
the specimen, and shows this on the built- in projection screen. From this screen there is usually a grid
that could be rotated 360 degrees therefore the X-Y axis of the screen could be aligned correctly using a

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straight edge of the machined part to analyze or measure. This projection screen shows the profile of the
sample and is zoomed for better ease of computing linear dimensions.
An edge of the sample to analyze could be aligned using the grid on the screen. After that, basic
measurements could be obtained for distances along with other points. This is being carried out on a
zoomed profile of the specimen. It could be easier and also lessen mistakes by measuring on the
magnified projection screen of a profile projector.
The conventional way of illumination is by diascopic illumination, and that is illumination from behind.
This kind of illumination is also known as transmitted illumination when the sample is transparent and
light can go through it. When the specimen is solid, then the light won‘t go through it, but can form a
profile of the sample. Measuring of the sample can be achieved on the projection screen. A profile
projector could also have episcopic illumination which happens to be light shining from above. This is
convenient in exhibiting bores or inner areas that needs to be measured.
Fig. Profile Projector
TABULATION
S.No. Major
diameter
D1
(mm)
Minor
diameter
D2
(mm)
Pitch
(mm)
Angle
(deg)
Depth
(mm)

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RESULT
Thus the thread parameter of the given screw thread was found using the pro file projector.
Major diameter = _______________ mm
Minor diameter = _______________ mm
Pitch of screw = ________________ mm
Depth of thread = ________________ mm
Angle of thread = ________________ mm
Questions:
1. What are vernier calipers?
2. What is least count (L.C.)?
3. What is the use of profile projector?
4. What is the Least Count of Profile Projector?
5. What is pitch circle diameter?
6. Name the different types of interferometer?
7. What is the principle of laser.
8. What is meant by alignment test on machine tools?
9. What are the different types of geometrical tests conducted on machine tools?
10. Define machine vision.

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Experiment-06
Aim: To determine the effective diameter of external thread by using three wire method
Apparatus required: Micrometer, three wire setup and bolt
Procedure: Using the Three-Wire Method to Measure Threads The pitch diameter of a threaded object
can’t be measured directly except with specialized thread micrometers. But using three wires of the
same known diameter, the thread pitch can be measured with a standard micrometer.
Making the Measurement
Let’s start by saying that it can be a little tricky handling three wires and a micrometer all at the same
time. There are several tricks of the trade that can make it easier, but learning to make the measurement
without “accessories” can ultimately be faster and more accurate.
Here’s the process for taking a measurement.
1. Put a shop towel under the work area to catch the wires you drop.

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2. Based on the pitch of the thread you are measuring, use the table below to select the proper set of
thread measuring wires.
3. Adjust your micrometer to about 0.010" larger than you expect your measurement to be.
4. Put two wires in adjacent V’s on the bottom of the part. Use the fixed anvil of the micrometer to hold
them in place.
5. Now on the top of the part, slip the third wire into a V under the movable anvil of the micrometer. 6.
Take your micrometer measurement. This process sounds harder than it is. I was successful on my
second try.
Some people use grease on the threads, rubber bands or modeling clay over the ends of the wires. Any
of these tricks will take longer than the method above, and they all can affect the accuracy of the
measurement.
Calculating the Pitch Diameter Now that you have your measurement, it’s a simple process to find the
pitch diameter.
1. Find the Constant for the thread pitch you are measuring from the chart below. (Note that a compact
version of this chart is included with the Pee Dee Thread Measuring Wires.)
2. Subtract the constant from the measured value. Here’s the formula:
E is the pitch diameter you are trying to find M is the measurement you took Const is the Constant value
from the chart.
E = M – Const
The photo above is measuring a piece of ½"–13 threaded rod. The micrometer reads 0.5112".
So the formula is:
E = M – Const
E = 0.5112" – 0.06838
E = 0.4428"
A ½"–13 class 2A thread (commonly used for fasteners) should be between 0.4485" and 0.4435", but it
is not surprising that threaded rod is somewhat small.
Wire Sizes and Constants

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How Does This Work?
In theory, you are measuring with wires of a known diameter that contact the threaded part on the pitch
line. As with most things in life, actual practice involves compromises. There are three formulas for
calculating appropriate wire sizes:
Smallest wire diameter = 0.56 × Pitch Largest wire diameter = 0.90 × Pitch Diameter for pitch-line
contact = 0.57735 × Pitch
If you do the math, you will find that all the suggested wires in the table above are between the smallest
and largest values.
The thread pitch for an American National Standard Unified 60° thread is:

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E = M + 0.86603P – 3W
Notice that if we know the pitch (P) and the wire diameter (W), then for any particular pitch, the
formula reduces to:
E = M – Const
where Const is a constant for a particular pitch and wire size combination. These are the constants given
in the table above. Take a look at the first formula for a moment. The value 0.86603 is a constant
because we are only considering 60° threads. It encapsulates some trigonometry involving the thread
angle. The 3W term is the interesting one. It highlights the fact that your thread measuring wires must
be the correct size. Any error in the wires is magnified three times. There is more to consider than wire
diameter. Bent, distorted, or dirty wires will also affect the measurement. (Rubber bands, anyone?)
Metric Threads Metric threads are also 60° threads so these formulas work just as well with them. The
following table shows the wires and constants for common metric threads. These constants assume you
are working in millimeters, not inches.
Result: Effective diameter of the given thread piece (bolt) is…
Viva Questions:

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1) Why are pitch errors observed in threads?
2) Which thread has a combined strength of square thread and V thread?
3) What is used to measure the major diameter of an external thread?
4) Which of the following statements is true?
5) Which method gives accurate results when effective diameter is measured without considering the
thread angle?
6) Why do we use 3 wire method?
7) Name the various methods of measuring the minor diameter of the thread.
8) Name the various methods for measuring effective diameter.
9) Name the two corrections are to be applied in the measurement of effective diameter.
10) What is best size of wire?
Experiment: 07
Aim: To measure the flatness of a given surface by using monochromatic light source and optical flat.
Apparatus: Optical flat, monochromatic light source, dry soft cloth, cleaning agent.
Theory:
Light band reading through an optical flat, using a monochromatic light source represent the most
accurate method of checking surface flatness. The monochromatic light on which the diagrammatic
interpretations of light wave readings are based comes from a source, which eliminates all colours
except yellowish color. The dark bands viewed under the optical flat are not light waves. They simply
show where interference is produced by reflections from two surfaces. These dark bands are used in
measuring flatness. The band unit indicates the level of the work that has risen or fallen in relation to the
optical flat, between the centre of one dark band and the center of the next dark band.
The basis of comparison is the reflected line tangent to the interference band and parallel to the line of
contact of work and the optical flat. The number of bands intersected by the tangent line indicates the
degree of variation from the true flatness over the area of the piece. Optical flats are used to check
flatness when surface to be tested shine and smooth i.e. Just like a mirror.
Optical flats are cylindrical piece made up of important materials such as quartz. Specification ranges
from 25mm by 38mm (dia x Length) to 300mm by 70 mm. Working surface are finished by lapping and
polishing process where as cylindrical surface are finished by grinding.

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Applications:
1. Optical flats are used for testing the measuring surfaces of instruments like micrometers, measuring
anvils & similar other devices for their flatness & parallelism.
2. These are used to calibrate the standard gauges, like slip gauges, angle gauges & secondary gauges in
the workshops.
3. In measuring the curvatures like convex and concave for surfaces of the standard gauges.
Observations:
1. Monochromatic yellow light source is used for conducting this experiment.
2. Wavelength of Monochromatic source of light.
Tabular Column:

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Calculations:
Procedure:
1. Clean the surface to be tested to become shiny and wipe if with dry clean cloth
2. Place the optical flat in between flatness of work piece to be tested and monochromatic
Sources of light i.e. on the work piece.
3. Both parts and flat must be absolutely clean and dry.
4. After placing optical flat over work piece switch on the monochromatic source of light and
Wait until getting yellowish or orange color.
5. Apply slight pressure over optical and adjust until getting steady band approximately parallel to the
main edges.
6. Count the number of fringes obtained on the flat with the help of naked eye and calculates the flatness
error
Results:
Measured the flatness of a given surface by using the optical flats.
Question:
1. Why is the spherometer so named?
2. What is the principle of a sphreometer?
3. What do you mean by the pitch of the spherometer?
4. What is the value of pitch and least countof spherometer used in your experiment?
5. State the formula for radius of curvature in your experiment?
6. What is meant by monochromatic source of light?
7. What is the function of a colimator?
8. Why do we use sodium vapour lamp in the laboratory as source of light?
9. What is the function of a colimator?

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Experiment .08
AIM: To check the accuracy of a ground of machined and lapped surface- (a) Flat surface (b)
Cylindrical surface.
Apparatus required: Spirit level, Flat & Cylindrical work pieces
a) Flat surface by master spirit level
It does not need to be perfectly level to start with, but must be within the range of the level you are
calibrating. The following steps must then be taken.
1) Clean the bearing surface, and the underside of the level to remove any dirt or dust. Then place the
level onto the bearing surface ready for inspection.
2) Note the position of the bubble after it has settled, (settling time can be up to 15 seconds) and then
turn the level by 180° and place back onto the surface in the same position as before.
3) Note again the position of the bubble after it has settled. If the level and the surface are set level, then
the bubble will be central on both readings. If the level is set level, but the bearing surface is out of
level, then the bubble will move in the same direction off-centre when the level is turned through 180°.
The surface can then be adjusted by this amount. If the bearing surface is set level, and the level is out
of level, then the bubble will move in different direction off-centre when the level is turned through

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180°. The level can then be adjusted to read level. If the readings are different, then both the level and
the surface need to be adjusted. Consider this example:
EXAMPLE 1 If the first bubble reading was 4 divisions to the left hand side, and the second reading
when rotated through 180° was 3 divisions to the right hand side:
The error in the level is half of the total error = (4+3)/2 = 3.5 divisions., The error in the surface is half
of the difference = (4-3)/2 = 0.5 divisions.
EXAMPLE 2 In the next example, the first reading is 3 divisions to the left, and the second reading
when rotated through 180° was 1 division to the left hand side:
The error in the level is half of the total error = (3-1)/2 = 1 divisions., The error in the surface is half of
the difference = (3+1)/2 = 2 division. In order to adjust the level, use the Allen key provided to turn the
adjustment screw accessible from the top cover of the level.

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(b) Cylindrical surface by Sphero meter
Or
To determine the radius of curvature of a spherical surface with a spherometer.
Apparatus Required :A spherometer, a plane glassplate, a metre scale, a piece of white paper and a
given spherical surface.
Description of Apparatus : The labelled diagram of spherometer is shown in Fig. It consists of a
metallic frame-work supported on the three fixed legs X, Y and Z of equal lengths. The legs have
pointed ends and are equidistant from one another. The pointed ends of these
legs form the three vertices of an equilateral triangle. A nut N is provided at
the centre of the frame through which passes a fine screw S. The lower part of
the screw is pointed and it is called the fourth or the central leg of the
spherometer. When it is brought in the plane of the remaining three legs, it
falls at the centre of the equilateral traingle formed by them i.e., all the three
vertices of the triangle are equidistant from it. A round disc of brass B is fixed
rigidly at the upper end of the screw S whose circumference is graduated in 50
or 100 equal divisions. This is called the circular scale of the spherometer.
There is a cap H (milled head) at the middle of the disc. Screw is made to
move up or down by rotating it. A vertical scale L, graduated in millimetre is fixed at one of the leg of
spherometer. It is called the main scale.
The zero mark of this scale lies at its middle. Its upper scale represents positive and lower scale
represents negative values. This scale just touches the disc so that the main scale and circular scale
readings can easily be taken.
Least count of spherometer =
Thus, the least count of spherometer is calculated just like as the least count a screw gauge. With the
help of milled head (or cap), the disc is given a full complete rotation and the distance through which
the edge of the disc moves, is noted. This distance is called the pitch of the screw. Then the total
number of divisions on the circular scale is counted. The pitch divided by the total number of divisions
on the circular scale gives the least count of the spherometer. Let the pitch of the screw be 1 mm and the
total number of divisions on the circular scale be 100,
then the least count of the spherometer =

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= 0.01 mm or 0.001 cm.
To escape from the zero error, while taking measurement, even if the zero is marked in middle of the
scale, it should be used by considering the zero at the lowest point of the scale. In this postion, since the
reading remains always above the zero mark, all the readings are positive. To avoid the backlash error,
the screw should always
be rotated in one direction only while taking the observation. If it is necessary to rotate the screw in
opposite direction, then first it should be rotated in the same direction to some extent and then in the
opposite direction.
Theory :Each spherical surface is a part of sphere whose radius is called
the radius of curvature of that spherical surface. First, the
spherometer is placed upon a plane glass plate and the reading is taken
when screw just touches the plate. Again the spherometer is placed on the
spherical convex surface and reading is taken when screw just touches
the spherical surface. The height of the spherical surface h = AC is obtained
by taking the difference of both the readings (Fig.). Now if the distance
between the fixed leg and the screw is XC = a and the radius of
curvature of spherical surface is R, then it is obvious from Fig.
OX = OA = R
and OC = OA – AC = (R – h)
Therefore, from the right angle triangle OCX,
OX2 = OC2 + CX2
or R2 = (R – h)2 + a2
or R2 = R2 – 2Rh + h2 + a2
or 2Rh = h2 + a2

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In Fig. X, Y, Z represent the positions of three legs ofspherometer and C is the position of its central
leg(or screw). XYZ is an equilateral traingle in whichthe distance between two legs XY = l and CX =
CY= CZ = a. In equilateral traingle XYZ, ZK is theperpendicular bisector as well as the median both.

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By knowing l and h, R can be calculated by usingthe above formula.
Where l= mean distance amongst the external legs of spherometer and h = height of the spherical
surface.
Method :
(1) First, to find the pitch of the spherometer, rotate the disc by four or six complete rounds and note the
distance moved by the disc on the main scale. Now divide this distance by the number of rotations to
calculate the pitch.

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Page 72
(2) Divide the pitch by the total number of divisions on the disc to calculate the least count.
(3) Now place the spherometer on a plane glass plate and rotate the central leg (or the screw) till the
screw just touches the plane surface. At this position, assuming zero at the lowest mark of main scale,
note the main scale reading and circular scale division which touches the edge of the main scale. After
then the circular scale ivision is multiplied by the least count. This reading is added to the main scale
reading to give the total reading.
(4) Now the spherometer is placed on the given convex spherical surface such that its external three legs
lie on this plane. The central leg is then turned down till it just touches the spherical surface. At this
position, assuming zero at the lowest mark, note the main scale reading and the circular scale division
which touches the edgs of the main scale. After then the circular scale division is multiplied by the least
count. This reading is then added to the main scale reading to give the total reading.
(5) The height h of the spherical surface is obtained by subtracting the first reading from the second
reading.
(6) The spherometer is then placed upon the left page of the practical note book and is slightly pressed
Three dots corresponding to the ends of the outer fixed legs of spherometer are imprinted on the paper.
By joining these three dots, an equilateral triangle is formed and by measuring the length of each side
with the help of metre scale, the mean length l between the external legs of spherometer is obtained.
Observations.
(1) For the determination of least count ofspherometer-
(2) Tables for the height h of the spherical surface-

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(i) On plane glass plate :
(ii) On convex spherical surface :
Calculation.
Height h of the spherical surface

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Page 74
= Mean reading on spherical surface– Mean reading on plane glass plate
= 0.394 cm. –0.362 cm. = 0.032 cm.
Radius of curvature of spherical surface
Result. Radius of curvature of the given sphericalsurface = 35.224 cm.
Viva Question:
1. Why is the spherometer so named?
2. What is the principle of a sphreometer?
4. What is the value of pitch and least countof spherometer used in your experiment?
5. State the formula for radius of curvature in your experiment?
6. What is accuracy?
7. What is the basic Principle of measurement?
8. What is Range of measurement?
9. What is Precision?
10. Define: Measurand.
EXPERIMENT NO-09
AIM:-Find out Chip reduction co-efficient (reciprocal of chip thickness ratio) during single point
turning.
Apparatus required: Lathe machine, MS work piece, single point cutting tool and vernier calliper
INTRODUCTION:

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This operation is one of the most basic machining processes. That is, the part is rotated while a single
point cutting tool is moved parallel to the axis of rotation.Turning can be done on the external surface of
the part as well as internally (boring). The starting material is generally a work piece generated by other
processes such as casting, forging, extrusion, or drawing.
In general, turning uses simple single-point cutting tools. Each group of workpiece materials has an
optimum set of tools angles which have been developed through the years.
Shank: The portion of the tool bit which is not ground to form cutting edges and is rectangular in cross
section.
Face: The surface against which the chip slides upward.
Flank: The surface which face the work piece. There are two flank surfaces in a single point cutting
tool. One is principal flank and the other is auxiliary flank.
Heel: The lowest portion of the side cutting edges.
Nose radius: The conjunction of the side cutting edge and end cutting edge. It provides strengthening of
the tool nose and better surface finish.
Base: The underside of the shank.

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ORTHOGONAL CUTTING PROCESS
The cutting edge or face of the tool is 900 to the line of action or path of the tool or to the cutting
velocity vector. This cutting involves only two forces and this makes the analysis simpler.
Figure: Ideal direction of chip flow in turning
Figure: Role of inclination angle, λ on chip flow direction
CHIP FORMATION
Mechanism of chip formation
Machining is a semi-finishing or finishing process essentially done to impart required or
stipulated dimensional and form accuracy and surface finish to enable the product to

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Page 77
 Fulfil its basic functional requirements.
 Provide better or improved performance.
 Render long service life.
 Machining is a process of gradual removal of excess material from the preformed blanks in the
form of chips.
 Nature and behavior of the work material under machining condition.
 Specific energy requirement (amount of energy required to remove unit volume of work
material) in machining work.
 Nature and degree of interaction at the chip-tool interfaces.
The form of machined chips depends mainly upon:
 Work material.
 Material and geometry of the cutting tool.
 Levels of cutting velocity and feed and also to some extent on depth of cut.
 Machining environment or cutting fluid that affects temperature and friction at the chip-
tool andwork-tool interfaces.
CHIP THICKNESS RATIO
Geometry and characteristics of chip forms
The geometry of the chips being formed at the cutting zone follow a particular pattern especially
in machining ductile materials. The major sections of the engineering materials being machined are
ductile in nature; even some semi-ductile or semi-brittle materials behave ductile under the compressive
forces at the cutting zone during machining.
The pattern and degree of deformation during chip formation are quantitatively assessed and
expressed by some factors, the values of which indicate about the forces and energy required for a
particular machining work.
Chip reduction coefficient or cutting ratio
The usual geometrical features of formation of continuous chips are schematically shown in
figure. The chip thickness (a2) usually becomes larger than the uncut chip thickness (a1). The reason
can be attributed to:
Compression of the chip ahead of the tool.
Frictional resistance to chip flow.
Lamellar sliding according to Piispannen.

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Page 78
The significant geometrical parameters involved in chip formation are shown in Figure and
those parameters are defined (in respect of straight turning) as:
t = depth of cut (mm) - perpendicular penetration of the cutting tool tip in work surface.
f = feed (mm/rev) - axial travel of the tool per revolution of the job.
b1 = width (mm) of chip before cut.
b2 = width (mm) of chip after cut.
a1 = thickness (mm) of uncut layer (or chip before cut).
a2 = chip thickness (mm) - thickness of chip after cut.
A1 = cross section (area, mm2) of chip before cut.
The degree of thickening of the chip is expressed by
rc = a2 / a1 > 1.00 (since a2 > a1)
where, rc = chip reduction
coefficient.
a1= f sinφ
where φ = principal cutting edge angle.
Larger value of rc means more thickening i.e., more effort in terms of forces or energy required
to accomplish the machining work. Therefore it is always desirable to reduce a2 or rc without
sacrificing productivity, i.e. metal removal rate (MRR).

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Chip thickening is also often expressed by the reciprocal of rc as,
1 / rc = r = a1 / a2
where r = cutting ratio.
The value of chip reduction coefficient, rc (and hence cutting ratio) depends mainly upon
Tool rake angle, γ
And Chip-tool interaction, mainly friction, μ
Roughly in the following way
and γ are in radians.
The simple but very significant expression 1.4 clearly depicts that the value of rc can be
desirably reduced by
 Using tool having larger positive rake.
 Reducing friction by using lubricant.
Chip reduction coefficient, rc is generally assessed and expressed by the ratio of the chip
thickness, after cut (a2) and before cut (a1) as in equation 1.1. But rc can also be expressed or assessed
by the ratio of:
Total length of the chip before cut (L1) and after cut (L2).
Cutting velocity, VC and chip velocity, Vf.
Considering total volume of chip produced in a given time,
a1b1L1 = a2b2L2
The width of chip, b generally does not change significantly during machining unless there is
side flow for some adverse situation. Therefore assuming, b1=b2 in equation 1.5, rc comes up to be,
rc = a2 / a1 = L1 / L2
Again considering unchanged material flow (volume) ratio, Q
Q = (a1b1)VC = (a2b2)Vf
Taking b1=b2,
rc = a2 / a1 = VC / Vf

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Equation reveals that the chip velocity, Vf will be lesser than the cutting velocity, VC and the
ratio is equal to the cutting ratio, r = 1 / rc
RESULT:
The chip reduction co-efficient is…
VIVA QUESTIONS:
1. What is turning operation?
2. What is orthogonal cutting?
3. What is ingle point cutting tool?
4. What is chip thickness ratio?
5. How chip is formed in turning?
EXPERIMENT NO. -10
AIM:-Forces measurements during orthogonal turning.
Apparatus required: Forces measuring kit and lathe machine setup
INTRODUCTION:
In machining or metal cutting operation the device used for determination of cutting forces is known as
a Tool Dynamometer or Force Dynamometer. Majority of dynamometers used for measuring the tool
forces use the deflections or strains caused in the components, supporting the tool in metal cutting, as
the basis for determining these forces. In order that a dynamometer gives satisfactory results it should
possess the following important characteristics:
1. It should be sufficiently rigid to prevent vibrations.

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2. At the same time it should be sensitive enough to record deflections and strains appreciably.
3. Its design should be such that it can be assembled and disassembled easily.
4. A simpler design is always preferable because it can be used easily.
5. It should possess substantial stability against variations in time, temperature, humidity etc.
6. It should be perfectly reliable.
7. The metal cutting process should not be disturbed by it, i.e. no obstruction should be provided
by it in the path of chip flow or tool travel.
8.
APPARATUS REQUIRED:
Lathe tool Dynamometer and Drill tool dynamometer.
TOOLS & MATERIAL REQUIRED:
HSS tool with tool holder, Φ25mm MS bar, and 10mm thick MS flat and 10mmdrill.
Types of Dynamometers:
Irrespective of their design and the technique used for strain measurement, most of the force
dynamometers used today carry a measuring system which is precalibrated for its stiffness. The cutting
forces are measured by these dynamometers by measuring the strain or deflection caused in this system
due to the force under measurement. The different types of commonly
used dynamometers can be broadly classified as:
9. Mechanical dynamometers
10. Strain Gauge type dynamometers
11. Pneumatic and Hydraulic dynamometers
12. Electrical Dynamometers
13. Piezoelectric dynamometers
PROCEDURE:
Lathe Tool Dynamometer:
Lathe tool dynamometer is used to measure cutting forces acting at the machining zone during turning
with a single point cutting tool. All the three directional forces are measured simultaneously.
Forces on a single point tool in turning:
In case of oblique cutting in which three component forces act
simultaneously on the tool point as shown. The components are:
Ft = The feed force or thrust force acting in horizontal plane parallel to the axis of
the work.
Fr = The radial force, also acting in the horizontal plane but along a radius of

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Work piece i.e. along the axis of the tool.
Fc = The cutting force, acting in vertical plane and is tangential to the work
surface. Also called the tangential force.
Figure: Force in turning operation
The work piece is fixed in a 3-jaw chuck with sufficient overhang.
1. Fix the dynamometer cutting tool in the tool post in such away that the tip of the tool coincides
with the lathe axis.
2. Select proper cutting speed, feed and depth of cut.
3. Perform turning operation on the work.
4. Directly measure the three components of forces acting on the tool using lathe tool
dynamometer.
5. Repeat the procedure for varying the above three parameters (CS, F & DC).
6. The resultant force can be calculated by
7. Observe the effect of cutting speed, feed and depth of cut on force.
Result:
The resultant force in the orthogonal cutting is …………….N
VIVA QUESTIONS:
1. What is orthogonal turning?
2. What is cutting speed
3. What is dynamometer?

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4. What is effect of cutting speed and feed rate on cutting force?
5. What specifications of single point cutting tool?
6. Define transducer?
7. What is the most common torque measuring principle?
8. What are the applications of torque measurement?
9. Mention some of the transducers.
10. Define sensitivity.
EXPERIMENT- 11
AIM: Torque and Thrust measurement during drilling
Apparatus required: Torque and Thrust measuring kit and drilling machine setup
INTRODUCTION:
Drilling is a cutting process that uses a drill bit to cut a hole of circular cross-section in solid materials.
The drill bit is usually a rotary cutting tool, often multipoint. The bit is pressed against the workpiece

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and rotated at rates from hundreds to thousands of revolutions per minute. This forces the cutting edge
against the workpiece, cutting off chips (swarf) from the hole as it is drilled.
In machining or metal cutting operation the device used for determination of cutting forces is known as
a Tool Dynamometer or Force Dynamometer. Majority of dynamometers used for measuring the tool
forces use the deflections or strains caused in the components, supporting the tool in metal cutting, as
the basis for determining these forces. In order that a dynamometer gives satisfactory results it should
possess the following important characteristics:
14. It should be sufficiently rigid to prevent vibrations.
15. At the same time it should be sensitive enough to record deflections and strains appreciably.
16. Its design should be such that it can be assembled and disassembled easily.
17. A simpler design is always preferable because it can be used easily.
18. It should possess substantial stability against variations in time, temperature, humidity etc.
19. It should be perfectly reliable.
20. The metal cutting process should not be disturbed by it, i.e. no obstruction should be provided
by it in the path of chip flow or tool travel.
DRILL TOOL DYNAMOMETER:
This is strain gauge Drill Tool Dynamometer designed to measure thrust and torque during drilling
operation. This dynamometer is suitable for drilling a hole up to 25mm size in Mild Steel. Drilling tool
dynamometer is a Rigid in construction, Compact Unit, Easy in handling and Assessment of cutting
forces by giving due consideration to various parameters like depth of cut, material, speed and feed.
Force systemin drilling:
During the process of drilling a lot of axial pressure (Thrust force) is applied on it in order to make it
penetrate into the material. On account of this pressure all the drill elements are subjected to one or
other type of force.
The principal forces are:
FH – An equal and opposite horizontal force acting on both lips of the drill and thus neutralizing each
other.
Fv - Vertical force acting at the centre of the drill in a direction opposite to that of the applied pressure.
Fv1 - Vertical force acting in the same direction as F , on the lips of the drill it is the main cutting force
in the operation.
Ff1 - Frictional force due to rubbing of upward flowing chips against wall of the hole and flutes of the
drill.

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Ff2 - frictional force due to rubbing between the drill margin and the hole surface.
P – The applied axial pressure or thrust force acting along the axis of drill to press it into the work piece
material.
In order that the drill penetrates into the work piece the applied pressure P, should be able to overcome
all the resistive forces acting against it.
P > (FV + 2FV1 + Ff1 + Ff2)
It is reckoned that as compared to FV and FV1 the magnitudes of the frictional forces Ff1 and Ff2 are
too small to be considered for practical purposes. Hence they are considered negligible. Therefore
P = FV + 2FV1
Thrust force acting on the drill, M = C d1.9 f0.8 N-mm
Where d is the diameter of the drill in mm
f is the feed per revolution, mm/rev
C is a constant depends upon the material to be machined
For Steel, C = 616

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Page 86
Aluminium alloys, C = 180
Magnesium alloys, C = 103
Brasses, C = 359
Torque acting on the drill is given by T = K d f0.7 N
For Steel, K = 84.7
Cast Iron = 60.5
 Fix the drill of a particular diameter in the drill chuck.
 Fix the work piece in vice mounted on the bed of the machine.
 Attach the drill tool dynamometer to the machine.
 Perform drilling operation on the work.
 Note down the values of thrust force and torque acting on the drill directly
 from drill tool dynamometer.
 Repeat the procedure by varying the speed, feed and depth of cut of the
 drill.
 Observe how these parameters will effects the force and torque.
PRECAUTIONS:
 The tool should be rigidly mounted on the lathe tool post.
 Make sure that there should not be any vibrations in the tool.
 Readings should be noted carefully.
 Select the cutting speed, feed and depth of cut properly.
RESULT:
The resultant thrust force and torque are…………..
VIVA QUESTIONS:

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Page 87
1. Define the drilling process.
2. What is tool dynamometer?
3. What type of forces act in drilling process?
4. What is difference between force measurement in turning on lathe and in drilling process?
5. What is cutting speed?
10. Define sensitivity

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EXPERIMENT NO-12
Aim: Forces measurement during plain milling operation
Apparatus required: Milling machine setup and force measuring kit
Introduction:
Milling is the most common form of machining, a material removal process, which can create a variety
of features on a part by cutting away the unwanted material. The milling process requires a milling
machine, work piece, fixture, and cutter. The work piece is a piece of pre-shaped material that is
secured to the fixture, which itself is attached to a platform inside the milling machine. The cutter is a

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cutting tool with sharp teeth that is also secured in the milling machine and rotates at high speeds. By
feeding the work piece into the rotating cutter, material is cut away from this work piece in the form of
small chips to create the desired shape.
Milling is typically used to produce parts that are not axially symmetric and have many features, such as
holes, slots, pockets, and even three dimensional surface contours. Parts that are fabricated completely
through milling often include components that are used in limited quantities, perhaps for prototypes,
such as custom designed fasteners or brackets. Another application of milling is the fabrication of
tooling for other processes.
Plain Milling
Plain Milling, also called Surface Milling or Slab Milling, is milling flat surfaces with the milling
cutter axis parallel to the surface being milled. Generally, plain milling is done with the workpiece
surface mounted parallel to the surface of the milling machine table and the milling cutter mounted on a
standard milling machine arbor. The arbor is well supported in a horizontal plane between the milling
machine spindle and one or more arbor supports.
Figure: Palin milling operation
Milling Cutters
All cutters that are used in milling can be found in a variety of materials, which will determine the
cutter's properties and the workpiece materials for which it is best suited. These properties include the
cutter's hardness, toughness, and resistance to wear. The most common cutter materials that are used
include the following:
 High-speed steel (HSS)
 Carbide
 Carbon steel
 Cobalt high speed steel
Cutting parameters
In milling, the speed and motion of the cutting tool is specified through several parameters. These

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parameters are selected for each operation based upon the work piece material, tool material, tool size,
and more.
 Cutting feed - The distance that the cutting tool or work piece advances during one revolution of
the spindle and tool, measured in inches per revolution (IPR). In some operations the tool feeds into
the workpiece and in others the workpiece feeds into the tool. For a multi-point tool, the cutting feed
is also equal to the feed per tooth, measured in inches per tooth (IPT), multiplied by the number of
teeth on the cutting tool.
 Cutting speed - The speed of the workpiece surface relative to the edge of the cutting tool during
a cut, measured in surface feet per minute (SFM).
 Spindle speed - The rotational speed of the spindle and tool in revolutions per minute (RPM).
The spindle speed is equal to the cutting speed divided by the circumference of the tool.
 Feed rate - The speed of the cutting tool's movement relative to the workpiece as the tool makes
a cut. The feed rate is measured in inches per minute (IPM) and is the product of the cutting feed
(IPR) and the spindle speed (RPM).
 Axial depth of cut - The depth of the tool along its axis in the workpiece as it makes a cut. A
large axial depth of cut will require a low feed rate, or else it will result in a high load on the tool and
reduce the tool life. Therefore, a feature is typically machined in several passes as the tool moves to
the specified axial depth of cut for each pass.
 Radial depth of cut - The depth of the tool along its radius in the workpiece as it makes a cut. If
the radial depth of cut is less than the tool radius, the tool is only partially engaged and is making a
peripheral cut. If the radial depth of cut is equal to the tool diameter, the cutting tool is fully engaged
and is making a slot cut.

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Cutting force =
RESULT :
The cutting force…… N
VIVA QUESTION:
1. What is milling machine?
2. What is cutting speed
3. What type milling cutter is use in milling?
4. What is feed rate?

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5. What is difference between plain milling and face milling?
10. Define sensitivity

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Page 93
EXPERIMENT NO. 13
AIM:-Measurement of Chip tool Interface temperature during turning using thermocouple technique.
Apparatus required: lathe machine setup and temperature measuring device
INTRODUCTION:
During the metal cutting process, a considerable amount of the machine energy is transferred into heat
through plastic deformation of the work piece surface, the friction of the chip on the tool face and the
friction between the tool and the work piece. The 99 per cent of the work done is converted into heat.
This results in an increase in the tool and work piece temperatures. The temperature distribution
depends on the heat conductivity and specific heat capacity of the tool and the work piece and finally
the amount of heat loss based on radiation and convection. The maximum temperatures occur in the
contact zone between the chip and the tool.
There are three main sources of heat generation during the process of cutting metal with a machine tool.
(a) Heat is produced in the primary shear zone as the work piece is subjected to large irreversible plastic
deformation (Shear- zone). (b) Heat produced by friction and shear on the tool rake face, or secondary
shear zone.
The chip material isfurther deformed and some adheres to the tool face. In this region the last layer of
atoms of the chip material are stationary. The velocity of the adjacent layers gradually increases until
the bulk chip velocity is attained. Thus there are both sticking and sliding friction sections. This

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