metrology and measurements lab.pdf
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` KONGU ENGINEERING COLLEGE
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LAB MANUAL
Degree : B.E
Year / Sem : II / IV
Course : Mechanical Engineering
Subject Code : 11ME508
Subject : METROLOGY AND MEASUREMENTS
LABORATORY
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11ME508 METROLOGY AND MEASUREMENTS LABORATORY
L T P C
0 0 3 1
Objective:
To familiarize the calibration and measurement process.
To study the characteristics of instruments.
To carry out the measurement of the length, angle, physical and thermal parameters of the
given object.
LIST OF EXPERIMENTS (Any 12 experiments) (Use slip gauges for calibration of length
measuring instruments)
LIST OF EXPERIMENTS /EXERCISES
1. Calibration of Vernier / Micrometer; static characteristic study. Measurement of
Components like V block etc.,.
2. Calibration of Internal micrometer and bore gauge; static characteristic study. Measurement
of components.
3. Calibration of Dial Gauge; static characteristic study; Use of dial gauge as measuring device
and comparator.
4. Calibration of Gear Tooth Vernier; static characteristics study; Measurement of gear tooth
thickness.
5. Calibration of LVDT and characteristic study; Use of LVDT as electronic comparator
6. Measurement/checking of Taper Angle using Bevel Protractor / Sine bar / Tool Makers
Microscope.
7. Measurement of straightness and flatness using autocollimator.
8. Measurement/checking of thread parameters using tool makers microscope/thread gauges
9. Checking the limits of dimensional tolerances using comparators (Mechanical / Pneumatic /
Electrical).
10. Calibration and characteristics study of dead weight pressure gauge
11. Dynamic characteristics study of glass thermometer- a first order instrument;
12. Use of CMM in metrology- Tracing the profile of a component and measurement of
dimensions
13. Machine alignment test (Lathe and special machines) like parallel and perpendicularity test.
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14. Use of Sampling Inspection & Control charts for Quality control.
15. Measurement of Force and torque(study experiment)
16. Measurement of Vibration / Shock(Demonstration experiment)
17. Study on measurement of light, sound, humidity, DBT, WBT, etc.
18. Temperature measurement using thermo couples, RTD etc.
TOTAL: 45
REFERENCES / MANUALS/SOFTWARE:
1. Jain, R. K., Engineering Metrology, Khanna Publishers, New Delhi, 2007.
2. Tayal, A. K, Instrumentation and Mechanical Measurements, Galgotia Publications, New
Delhi, 2006.
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PROGRAMME OUTCOMES
Definition and Validation of Course Outcomes and Programme outcomes
List the Course Outcomes (COs) and Programme Outcomes (POs)
The course outcomes and programme outcomes of Mechanical Engineering are listed as
below:
List of Course Outcomes (COs)
On completion of each course, the student will be able to
11ME508 Metrology and
Measurements Laboratory (MML)
i. demonstrate the knowledge/skill on standards,
calibration process and analyze the characteristics of
instruments
ii. demonstrate the knowledge/skill on measurement of
length, angle and form surface measurement.
Programme Outcomes:
A total of 13 program outcomes have been formulated for the Mechanical
Engineering program. These outcomes are defined as the skills and competencies students are
expected to have at the time of graduation. The Program Outcomes are:
Graduates will demonstrate
a. An ability to apply knowledge of mathematics, science and engineering.
b. An ability to design and conduct experiments, as well as to analyze and interpret data.
c. An ability to design a system, component, or process to meet desired needs within realistic
constraints.
d. An ability to function in multidisciplinary teams.
e. An ability to identify, formulate and solve engineering problems.
f. An understanding of professional and ethical responsibility.
g. An ability to communicate effectively.
h. The broad education necessary to understand the impact of engineering solutions in a
global and societal context.
i. Recognition of the need for and an ability to engage in continuous learning.
j. Knowledge on contemporary issues.
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k. An ability to use the techniques, skills and modern engineering tools necessary for
engineering practice.
l. An ability to work professionally in thermal, manufacturing and mechanical systems areas
including the design and realization of such systems with the use of computational tools.
m. An ability to demonstrate knowledge and understanding of economics/financial
management, project management and entrepreneurship skills.
Course: 11ME508 Metrology and Measurements Laboratory (MML)
PO /CO a b c D E f g h i j k l m
i)
ii)
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INDEX
S.No Date Content Page
No
Marks Awarded
Sign CoE
(10) Obs
(10) Rec
(10) Viva
(10) Total
40
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TOTAL
CoE - Conduct of Experiment
Obs - Observation
Rec - Record
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INSTRUMENTS LIST
S.NO NAME OF EQUIPMENT/INSTRUMENT
1 PORTABLE SURFACE ROUGHNESS TESTER
2 UNIVERSAL BEVEL PROTRACTOR
3 DIAL INDICATOR WITH MAGNETIC STAND
4 GEAR TOOTH VERNIER CALIPER
5 VERNIER DEPTH GAUGE
6 SCREW THREAD MICROMETERS
7 CO-ORDINATE MEASURING MACHINE
8 AUTOCOLLIMAETOR
9 FLOATING CARRIAGE MICROMETER
10 GEAR TOOTH VERNIER
11 TOOLMAKERS MICROSCOPE
12 TORQUE TRANSDUCER
13 LOAD CELL
14 GRANITE SURFACE PLATE
15 INSPECTION BENCH CENTER
16 ELEVTRONIC COMPARATOR (LVDT)
17 PITOT TUBE & PITOT CYLINDER
18 THERMOCOUPLES & THEROMETER
19 PROFILE PROJECTOR
20 AIR GUAGING EQUIPMENT
21 STRAIN GUAGE APPARATUS
22 VERNIER CALLIPER
23 VERNIER HEIGHT GAUGE
24 OUTSIDE MICROMETER
25 INSIDE MICROMETER
26 DEPTH MICROMETER
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S.no Name of equipment/Instrument
27 CYLINDER BORE GUAGE
29 VERNIER BEVEL PROTRACTOR
30 SINE BAR
31 SLIP GUAGE
32 FEELER GUAGE,SCREW PITCH GUAGE , RADIUS GUAGE
33 DIAL TEST INDICATOR
34 MAGNETIC BASE
35 V-BLOCK
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EXERCISE LIST
S.NO NAME OF EXPERIMENT Page
No
1. Calibration of dial gauge and measurement of component 11
2. Calibration of bore gauge, inside micrometer and measurement of the component 14
3. Calibration of depth gauge, vernier height gauge and measurement of the component 19
4. Calibration of LVDT and compare and check the dimensional tolerance using LVDT or ELECTRICAL COMPARATOR
23
5. Calibration of vernier caliper and micrometer and measurement of the given component 27
6. Measurement of taper angle by using sine bar 32
7. Calibration of gear tooth vernier and measurement of gear tooth thickness by gear tooth vernier caliper
35
8. Flatness and straightness checking using autocollimator
39
9. Measurement of the various dimensions by using Electronic comparator
42
10. Characteristics of first order instrument thermometer
45
11. Measurement of force using a proving ring 49
12. Power measurement using rope brake dynamometer 52
13. Calibration and draw the profile by using Profile projector 54
14. Angle measurement using bevel protractor 57
15. Hysterisis curve of a cantilever beam 61
16. Measuring cylinder and cone dimensions coordinate measuring machine 63
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Ex.No : Date:
CALIBRATION OF DIAL GAUGE AND MEASUREMENT OF COMPONENT
AIM
To calibrate the dial gauge using slip gauge and to measure the given components
using dial gauge.
APPARATUS REQUIRED
V - Block, Dial gauge with stand, Work piece, Slip gauges.
PROCEDURE
Calibration
1. The dial gauge is fitted to the stand to match the range of calibration of the dial
gauge.
2. Adjust the dial gauge reading to zero with respect to reference plane.
3. Insert the selected length standard (slip gauge) between the reference surface and the
dial gauge plunger .
4. Repeat step 3 for the incremental increaser standard input.
5. Note down output values for the each of standard inputs.
6. Calculate error in Dial Gauge.
7. Plot a graph of (i). Standard input vs Output and (ii). Standard input vs Error
8. Calculate sensitivity of the instrument.
Measurement
1. Without disturbing the calibration setup insert the work piece to be measured between
the reference surface and the Dial Gauge plunger.
2. Set a datum point or line.
3. Observe the Dial Gauge reading by moving the work piece to the edges for
measurement.
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4. Note down the reading of all the measurement.
5. Calculate compensating factor based on the error in the instrument.
6. Give a report of the work piece.
CALIBRATION OF DIAL GAUGE
S.No STD Dimension
in
mm
Reading From Dial Gauge Average
Error in
mm
R1 in mm R2 in mm R3 in mm mm deg
1
2
3
4
5
6
7
8
9
10
CHARACTERISTICS OF DIAL GAUGE
Range = mm
Span = mm
Least Count = mm
Linearity =
Output / Input =
% Linearity = %
Error/Bias = mm
Compensation Factor = mm
Sensitivity =
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MEASUREMENT OF SPECIMEN
S.No Parameter
measured
Observed Readings in mm
Compensating
factor in mm
Actual Readings in
mm
1
2
3
4
5
6
7
8
9
10
MODEL GRAPH
Output Error
Standard Input Standard Input
RESULT
Error of the instrument :
Sensitivity :
Lest count :
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Ex.No : Date:
CALIBRATION OF BORE GAUGE, INSIDE MICROMETER AND
MEASUREMENT OF THE COMPONENT
AIM
To calibrate the Bore Gauge and Inside Micrometer and also to measure the given
component.
APPARATUS REQUIRED
Vernier Calliper, Inside Micrometer, Bore gauge, Slip gauges, Component.
PROCEDURE
Calibration
1. Note down the range of instrument and the plunger displacement of the Bore Gauge.
2. Use a standard venier calliper as standard length and calibrate the gauges.
3. Note down the readings and plot the calibration graph.
4. Find the Least count, Error, Sensitivity of the instrument etc.,
Measurement
1. Insert the gauge into the given cylindrical work piece and carry out measurement at
different plane and at different position.
2. Draw a circularity graph and give a report of the circularity and taper of work pieces.
3. Give a report of the measurement.
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CALIBRATION OF THE BORE GAUGE & INSIDE MICROMETER
S.
No
Name of the
instrument Standard Input
values
in mm
Output values in mm Error in
mm I. II. III.
Average
values
1
BO
RE
GA
UG
E
2
3
4
6
7
8
9
10
11
INS
IDE
MIC
RO
ME
TE
R
12
13
14
15
16
17
18
19
20
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CHARACTERISTICS OF BORE GAUGE
Range :
Span :
Error : % Error
Compensation factor :
Least count =
CHARACTERISTICS OF INSIDE MICROMETER:
Range :
Span :
Error of the instrument :
Compensation factor :
Least count :
Sensitivity :
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MEASUREMENT OF THE COMPONENT:
S.no Instrument
used Plane Position
Observed
Reading in mm
Compensation
Factor
Actual Reading
in mm
1
2
3
4
5
6
7
8
9
10
MODEL CALCULATION FOR BORE GAUGE:
Measured value = MSR + (VSC*LC)
Correct value = measured value + zero correction
MODEL CALCULATION FOR INSIDE MICROMETER:
Measure value = MSR + (PSR*LC)
Correct value = measured value + zero correction
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BORE GAUGE SENSITIVITY ANALYSIS:
RESULT:
Least count of the Instrument:
Error :
Sensitivity :
Attach the analysis report :
S.no
Input
value
In mm
Output value
Average value
Error in
mm
I II
Div Rad Div Rad Div Rad
1
2
3
4
5
6
7
8
9
10
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Ex.No : Date:
CALIBRATION OF DEPTH GAUGE, VERNIER HEIGHT GAUGE AND
MEASUREMENT OF THE COMPONENT
AIM
To calibrate the venire height gauge and depth gauge and to measure the given
component.
APPARATUS REQUIRED
Venire Height Gauge, Depth Gauge, Slip Gauge.
Calibration
1. With the help of slip gauges as standard, calibrate the gauges .
2. Plot a graph of (i) Standard Input vs Output and
(ii) Standard Input vs Error
3. Observe the characteristics like error, least count, sensitivity, etc.,
Measurement
1. Place the work piece and the gauge appropriately and carry out the measurement of
the job.
2. Prepare a report of the measurement and indicate the characteristics of the work
pieces.
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CALIBRATION OF DEPTH GAUGE
S.
No
Name of
instrument
Input value
in mm
Output value in mm Error in
mm I II III Average value
1
DE
PT
H G
AU
GE
2
3
4
5
6
7
8
9
10
CALIBRATION OF VERNIER CALIPER
S.
No
Input value
in mm
Output value in mm Error in
mm I II III Average value
11
VE
RN
IER
HE
IGH
T G
AU
GE
12
13
14
15
16
17
18
19
20
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CHARACTERISTICS OF DEPTH GAUGE:
Range :
Span :
Least count :
Sensitivity :
Error :
CHARACTERISTICS OF VERNIER HEIGHT GAUGE:
Range :
Span :
Least count :
Sensitivity :
Error :
MEASUREMENT OF THE COMPONENT:
Position MSR in mm PSR in Div OR=MSR+(PSR*LC) in mm CR=OR+ZC in mm
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MEASUREMENT OF THE COMPONENT:
Parameter
measured
MSR
in mm
VSR
in DIV
OR=MSR+(PSR*LC)
in mm
CR=OR+ZC
in mm
RESULT
Depth gauge
Least count of the Instrument :
Error :
Sensitivity :
Vernier Height gauge
Least count of the Instrument :
Error :
Sensitivity :
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Ex.No : Date:
CALIBRATION OF LVDT AND COMPARE AND CHECK THE DIMENSIONAL
TOLERANCE USING LVDT OR ELECTRICAL COMPARATOR
AIM
To calibrate the LVDT and to measure the incremental input.
APPARATUS REQUIRED
LVDT, Micrometer, Slip gauge.
PROCEDURE
Calibration
1. Note down the range and span of LVDT .
2. Chose suitable slip gauges to make enough number of readings for calibration.
3. Set the LVDT such that when the plunger is at the middle, indicating zero output.
4. Calibrate the LVDT on both side of plunger movement from its mean position.
5. Plot a graph of (i) Standard Input vs Output and
(ii) Standard Input vs Error
6. Calculate the error, least count, sensitivity, etc.,
Measurement
1. Insert the work piece to be measured, between the reference plane and LVDT plunger
with out disturbing the calibration setup.
2. Note down the indicated readings or the difference between the standard value and the
indicated reading if used as a comparator.
3. Make enough number of readings if used as a comparator and classify the items
indicated as accepted or rejected and produced a statistical report.
4. If its a measurement of a job, then produce a report of measurement.
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CALIBRATION OF LVDT
Basic size: Increment/Decrement =
S.NO STD Input Output
micron
Output
value in mm
Error
(m) mm m
1
2
3
4
5
6
7
8
9
10
Average error = m
Compensation factor = m
CHARATERISTICS OF ELECTRICAL COMPARATOR:
Range =
L.C =
Compensation factor =
Sensitivity = Change in output signal
Change in input signal
Accuracy = output-input
Input
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CHECKING OF COMPONENT: Compensation factor = m
Piece Readings Displayed/ Attribute outcome
in micron
Compensation
Factor
Actual Value
in micron
MODEL CALCULATION:
Error =
Compensation factor =
L.C =
Sensitivity = Change in output signal
Change in input signal
Accuracy = output-input
Input
Error =
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MODEL GRAPH:
Output Error
Standard Input Standard Input
RESULT:
Error of the instrument :
Least count :
Sensitivity :
Accuracy :
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Ex.No : Date:
CALIBRATION OF VERNIER CALIPER AND MICROMETER AND
MEASUREMENT OF THE GIVEN COMPONENT
AIM
To calibrate and measure the given component by using vernier calliper and
micrometre.
APPARATUS REQUIRED
Slip gauges, Micrometer and Vernier Calliper.
PROCEDURE
Calibration
1. With the help of slip gauges as standard, calibrate the gauges.
2. Plot a graph of (i) STD Input vs Output and
(ii) Standard Input vs Error .
3. Observe the characteristics like error, least count, sensitivity etc.,
Measurement
1. Place the work piece and the gauge appropriately and carry out the measurement of
the job.
2. Prepare a report of the measurement and indicate the characteristics of the work
pieces.
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CALIBRATION OF VERNIER CALIPER:
CHARACTERISTICS OF VERNIER CALIPER:
Parameter Formula used Result
Range -
Span -
Error -
Compensation factor -
Least count
value of 1MSD
no of VSD
Sensitivity
change in O/P
change in I/P
S.NO Slip gauge in
mm
MSD VSD Output value
in mm
Actual value in
mm
Error in
mm
1
2
3
4
5
6
7
8
9
10
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MEASUREMENT OF THE COMPONENT:
CALIBRATION OF MICROMETER:
S.No Slip Gauge MSD in mm PSD in mm Out put value in mm Error in mm
1
2
3
4
5
6
7
8
9
10
S.no Position of component MSR in mm VSD in DIV VSR in
mm
Output
value in
mm
Actual
vlaue in
mm
1
2
3
4
5
6
7
8
9
10
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CHARACTERISTICS OF MICROMETER:
Parameter Formula used Result
Range
-
Span
-
Error
-
Compensation factor -
Least count Value of 1 PSR
Number of PSD
Sensitivity
Change in O/P
Change in I/P
MEASUREMENTS OF COMPONENT:
Position of
component HSD in mm PSD in mm PSD*LC
Out put
value Actual value mm
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RESULT:
Vernier calliper
Error of the instrument :
Least count :
Sensitivity :
Accuracy :
Micrometer
Error of the instrument :
Least count :
Sensitivity :
Accuracy :
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Ex.No : Date:
MEASUREMENT OF TAPER ANGLE BY USING SINE BAR
AIM
To measure taper angle of given work piece by sine bar.
To set the given sine bar to the given angle.
APPARATUS REQUIRED
1. Sine Bar 2.Slip gauge 3.Workpiece
PROCEDURE
Measurements of Taper Angle
1. Set the work piece to measure the taper angle using sine bar and dial gauge.
2. Transverse the dial gauge plunger over the ramp of work piece.
3. Note down the initial reading, final reading and the length of the traverse.
4. Alternately, try to king the inclined surface of the work piece ,whose taper angle is to
be measure ,to the horizontal plane by placing suitable combination of slip gauge
under the lower end of the work piece.
5. Note down the length of the slip gauge.
6. Calculate the taper angle through the formula given.
Setting the given sine bar to the given angle
Take note of the given angle for which the top surface of the sine bar is to be set.
1. Theoretically calculate the height of the slip gauge required to lift one end of sine bar
Such that top surface of the sine bar make the required slope.
2. Insert the selected combination of slip gauge under one end of the sine bar.
3. Use dial gauge with stand and traverse the plunger of the dial gauge over a know length
and check the slope of the sine bar.
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SINE BAR DIGRAM
MEASUREMENT OF GIVEN TAPER ANGLE USING SINE BAR:
MODEL CALCULATION:
=
S.No Length of sine bar
(mm)
Height of Slip Gauge
(mm)
Difference in
Height
(mm)
Angle
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USING DIAL GAUGE:
S.NO Length of bar
(mm)
Height obtained (mm)
(mm)
Angle in deg
RESULT:
1. The angle measurement is.........
2. Also sensitivity of sine bar .............................degree have been carried out
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Ex.No : Date:
CALIBRATION OF GEAR TOOTH VERNIER AND MEASUREMENT OF GEAR
TOOTH THICKNESS BY GEAR TOOTH VERNIER CALIPER
AIM
To calibrate the gear tooth vernier and to measure the thickness of gear tooth.
APPRATUS REQUIRED
Gear tooth vernier and slip gauge.
PROCEDURE
Calibration
1. Note down the range of the vernier scale in X and Y axis.
2. Select suitable slip gauges and calibrate X and Y axis independently.
3. Produce a calibration report and draw necessary graph.
4. Note down the error in the instrument if any.
Measurement
1. Calibrate the instrument using slip gauge.
2. Find outside diameter of given gear using vernier calliper and count number of tooth in
gear.
3. Calculate pitch scale circle diameter of given gear using formula
Pitch diameter = N*OD/ (N+2) mm
Where,
OD = outer diameter of gear.
N = number of teeth
Module (m) = D/N mm
Addendum = (Nm/2) [1+ (2/N)-cos (90/N)]
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4. Find out tooth thickness in mm
Tooth thickness = N*m *sin (90/N)mm
5. Set variable side of calculated addendum of job place side on top gear tooth to be
measured.
6. Repeat it for variable tooth and find average tooth thickness of given gear.
7. Thickness of the tooth = 2.70mm
CALIBRATION OF THE GEAR TOOTH VERNIER :
Sno
Axis
STD
Input
in mm
Output value in mm Average
output in
mm
Error in
mm I II II
1
X
2
3
4
5
Y
6
7
8
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CHARATERISCTICS OF GEAR TOOTH VERNIER:
Parameter Formula Result
Range -
Span -
Least count Distance moved
(no. of PSD)
Sensitivity Change in output
Change in input
Model Graph:
MEASUREMENT OF THE COMPONENT:
Tooth No MSR in mm VSR in mm OR in mm CR in mm
E
R
R
O
R
INPUT
O
U
P
U
T
INPUT
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OBSERVATION:
Number of teeth on gear=
Outer diameter=
CALCULATION:
RESULT:
Thus the thickness of tooth was found out and compared with practical value.
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` KONGU ENGINEERING COLLEGE
(Autonomous)
PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No : Date:
FLATNESS AND STRAIGHTNESS CHECKING USING AUTOCOLLIMATOR
AIM
To check the flatness and straightness of the given component using autocollimator.
APPARATUS REQUIRED
1) Auto collimator
2) Work piece /object to be tested
DESCRIPTION
An optical system of an auto collimator consists of a light source, condensers, semi-
reflectors, target wire, collimating lens and reflector apart from microscope eyepiece. A
target wire takes place of the light source into the focal plane of the collimator lenses. Both
the target wire and the reflected image are seen through a microscope eyepiece.
The eyepiece incorporates a scale graduated in 0.05mm interval and a pair of parallel
setting wires which can be adjusted. Movements of wires are effected through a micrometer,
one rotation of the drum equals to one scale division movement of the wires.
The instrument is designed to be rotated through 90 degrees about its longitudinal axis
so that the angles in both horizontal & vertical planes are measured.
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PROCEDURE:
1) Keep the auto collimator on the reference surface.
2) Place the reflector on the surface to be tested, such that the reflected beam of light
goes back to the collimating lens.
3) The position of auto collimator is adjusted until the two target wires set in focal plane
of instrument are each covered.
4) Any horizontal tilt in the surface under test leads to vertical target wire to move to the
right.
5) The angular tilt 20 of the reflector is obtained by taking into account the distance (d)
between wires.
d=2Fd
Where, F=Focal length of collimating lens.
TABULATION:
Mirror distance
(mm)
Micrometer reading(mm) Average(mm)
Angle
Tan=y/x A B C
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RESULT:
The values are analyzed and necessary modification of the surface may be
recommended based on the accuracy required on flatness. If the values observed from the
micrometer are varying linearly then straightness/flatness can be judged.
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` KONGU ENGINEERING COLLEGE
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Ex.No : Date:
MEASUREMENT OF THE VARIOUS DIMENSIONS BY USING
ELECTRONIC COMPARATOR
AIM
To compare the dimensions of given work pieces with length standards using an
Electronic comparator.
APPARATUS REQUIRED
Electronic comparator, slip gauge set and work pieces
DESCRIPTION
The Electronic comparator consists of LVDT (Linear Variable Differential
Transformer) as transducer fitted on a stand. The position of the LVDT can be changed. The
LVDT provides an a.c. voltage output proportional to relative displacement of transformer
core to the windings. The LVDT has three coils; the center or primary coil(P1) is energized
from the external a.c. source. The two secondary identical coils(S1,S2) which are connected
together in phase opposite as shown in fig.
The output amplitude and phase depends on the relative coupling between the two pick
up coils and power coils. There should be a core position for which the voltage induced in
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` KONGU ENGINEERING COLLEGE
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each pickup coil will be of same magnitude, and the resulting output will be zero. The linear
range of LVDT is primarily dependent on the length of the secondary coils.
PROCEDURE:
1. First the system is switched on and the slip gauge (size equal to the design
dimension of the parameter being checked) is placed between the worktable and
the sensor of LVDT. The table height is adjusted so that the display unit shows
zero.
2. Then the slip gauge is removed and the work-pieces manufactured for the set
design dimensions are inserted between the table and the sensor of LVDT one by
one.
3. The display unit displays the deviation(microns) of the work piece dimension from
the standard value.
4. The jobs whose deviations are within the specification limits (customer specified)
are accepted and the rest are rejected (scrap or rework).
TABULATION
Setting.no Slip gauge
size(mm)
Indicated diff in microns Remarks
lot 1
a)
b)
c)
d)
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Setting.no Slip gauge
size(mm)
Indicated diff in microns Remarks
lot 2 a)
b)
c)
d)
Result:
The scrap and reworks are identified and separated. Only the work-pieces confirming to
the specifications are accepted. This type of separating defectives has found acceptability in
mass production of components
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` KONGU ENGINEERING COLLEGE
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PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No: Date:
CHARACTERISTICS OF FIRST ORDER INSTRUMENT THERMOMETER
AIM
To find the following using thermometers
1) Range of thermometer.
2) The steady state response time.
3) Time constant of the instrument and to draw the time Vs response curves.
APPARATUS REQUIRED
1) Alcohol filled thermometer
2) Mercury filled thermometer
3) Stop watch
DESCRIPTION
Glass thermometer is one of the common type of temperature measuring device .The
envelope comprises of thick walled glass capillary tube ,a spherical wall bulb filled with the
liquid at the bottom and a small bulb at its top end act as safety reservoir. A change in
temperature will cause the liquid to expand or contract in the stem. The raise and fall of liquid
in the capillary against the calibrated scale indicates the temperature of the source.
PROCEDURE:
1) The thermometer bulb is dipped in the water at high temperature (temperature source).
2) Thermometer readings are noted for every equal interval of time until we get steady state
reading.
3) Then the above procedure is repeated with ice water as the temperature source and
thermometer readings are noted.
4) Graphs are plotted between time and response.
5) Time to get 63.3% response is found out.
6) The horizontal line in the plot indicates the steady state condition.
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VERIFICATION OF THE THEORETICAL RESPONSE WITH THE EXPERIMENTAL
VALUES:
HOT WATER SOURCE:
O = i (-t/)
Theoretical Response after 10 sec =
Experimental value after 10 sec =
COLD WATER SOURCE:
O =i (-t/)
Theoretical Response after 10 sec =
Experimental value after 10 sec =
TABULATION:
ALCOHOL THERMOMETER
(A) COLD WATER
S.NO TEMPERATURE(C) TIME
(SEC)
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(B) HOT WATER
S.NO TEMPERATURE(C) TIME
(SEC)
1) MERCURY THERMOMETER
(A) COLD WATER
S.NO TEMPERATURE(C) TIME
(SEC)
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(B) HOT WATER
S.NO TEMPERATURE(C) TIME
(SEC)
Model Graph
RESULT:
Thus the experiment is conducted in liquid thermometer, the variation of time with
temperature is noted and graph is plotted and time constant was found.
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Ex.No: Date:
MEASUREMENT OF FORCE USING A PROVING RING
AIM:
To understand the elastic transducers and measure the force applied on a proven ring.
APPARATUS REQUIRED:
1) Proving ring
2) Displacement measuring and indicating device-dial gauge
DESCRIPTION:
A proving ring is a ring of known physical dimensions and mechanical properties.
When an external compressive or tensile load is applied to lugs or external bosses, the ring
change its diameter, the change being proportional to the applied force. The amount of ring
deflection is measured by means of a highly sensitive displacement measuring device. A dial
gauge/electrical strain gauge system may be used as a secondary transducer.
PROCEDURE:
1) Clamp the proving ring rigidly.
2) Ensure the secondary displacement transducer is properly aligned.
3) The axis of the dial gauge plunger and the line of forces should coincide.
4) Apply a known force at the top most point of the proving ring.
5) Increase the input force in steps and note down the corresponding reading in the dial
gauge.
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TABULATION
Load in
Kg
Load in g(Defelction in div) Unload in g(Defelction in div) Deflection
for Loading
in mm
Deflection
for
unloading
in mm
I II III I II III
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MODEL GRAPH:
Range:
Least Count :
Sensitivty : Change in O/P/ Change in I/P
Proving ring sensitvity :
Dial Gauge sensitvity:
Overal Sensityvity :
RESULT:
Thus the instrument behaves linearly and the linearity range depends upon the
material property of the proving ring.
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` KONGU ENGINEERING COLLEGE
(Autonomous)
PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No: Date:
POWER MEASUREMENT USING ROPE BRAKE DYNAMOMETER
AIM
To measure the power and torque by conducting a load test on engine and to draw the
characteristic curves
a) Torque vs. load
b) Power vs. load
APPARATUS REQUIRED
1) Tachometer
2) Measuring tape
3) Spring balance
DESCRIPTION
A rope brake dynamometer consists of one or more rope wrapped around the flywheel
of engine and brake drum whose power is to be measured. The ropes are placed evenly across
the width of the drum. The upward rings of ropes are connected to the spring balance on each
side. The rotation of flywheel produces frictional force and ropes are tightened and
consecutively a force is exerted on the drum. Due to this enormous amount of heat is
produced. The heat is removed using water as coolant.
PROCEDURE:
1) Check the fuel supply to engine, lubrication oil level in the oil pump, water circulation
in the cooling system, etc.
2) Start the engine and ensure no load condition on the brake drum.
3) Allow the engine to stabilize before loading.
4) Now the load is applied gradually on the rope brake dynamometer.
5) For every increase in load, the speed is measured using tachometer.
6) Repeat the procedure for various load and power is measured.
7) Calculate the torque and power using the given formulae.
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SAMPLE DATA:
1) Speed, N = 1500 rpm
2) Radius of the brake drum, R = 0.2 m
3) Theoretical power applied = 1.5 kW
4) Theoretical torque = P*60/(2*pi*N) N-m
5) Actual Torque= W * 9.81 * R N-m
RESULT:
Thus the torque and power measurement is done using rope brake dynamometer.
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` KONGU ENGINEERING COLLEGE
(Autonomous)
PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No: Date:
CALIBRATION AND DRAW THE PROFILE BY USING PROFILE PROJECTOR
AIM
1) To calibrate profile projector.
2) To check the dimensions of small size components using a profile projector.
3) To draw the profile of the given job.
APPARATUS REQUIRED
1) Profile Projector
2) Small Screws/Small Gears
DESCRIPTION
The profile projector is basically an optical instrument/comparator which makes use
of the enlarged image principle. The purpose of optical projector is to compare the shape or
profile of a relatively small engineering component with an accurate standard or drawing. It
throws an enlarged image of the component onto a screen. The magnification of the system
will be equal to the size of the object image in screen divided by size of the component. The
available magnified are 10x, 20x & 50x.
CALIBRATION PROCEDURE:
1) The least count of the micrometer in the profile projector is noted down.
2) A standard input (slip gauge) is projected onto the screen and the screen reading is
noted.
3) The error is calculated from the standard input & the output readings are calculated.
4) Then while taking the reading of job, the error is suitably compensated.
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CALIBRATION:
S.NO. Std Input
(mm)
Micrometer Readings Template Reading
Remarks Initial
(mm)
Final
(mm)
Net
(mm)
Screen
Reading
Actual
reading(S.R/
M.F)
CALIBRATION REPORT OF PROFILE PROJECTOR:
Characteristics Quality
Sensitivity
Least count at template
Error
Magnification factor
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MEASUREMENT PROCEDURE:
1) Initially clean the work piece and the table.
2) The fan is switched on and the episcope is turned on.
3) The height of the table is adjustable, so that the clear image of the work piece is seen
on the screen.
4) Then using the micrometer provided for X-direction & other one for Y-direction,
image of the object could be positioned & matched with a template location on the
screen. The worktable is moved with a template location on the screen. The worktable
is moved with the help of micrometer. The readings of the micrometer & that of the
screen are noted.
5) Then by imposing a graph sheet on the screen the profile is plotted for further
reference.
TABULATION:
S.NO.
Parameter
under Test
Micrometer
Readings(mm) Template Reading(mm)
Remarks Initial
Final
Net
Screen
Reading M.F
Actual
reading(S.R/
M.F)
RESULT
Thus, the profile projector is calibrated & the various parameters of a given watch
stud are measured.
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` KONGU ENGINEERING COLLEGE
(Autonomous)
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Ex.No: Date:
ANGLE MEASUREMENT USING BEVEL PROTRACTOR
AIM:
To measure the angle of the given work-piece using Bevel protractor.
.APPARATUS REQUIRED:
Bevel protractor work-piece. Rollers and pins shafts
DESCRIPTION:
The equipment consists of a vernier protractor with a movable measuring blade and a
reference blade. The blades are adjustable for both angle and length and are readily applied to
a variety of measuring applications.
The main scale is graduated in degrees of arc. The vernier scale has 12 divisions
each side of the centre zero. These are marked 0-60 minutes of arc, so that each division
equals 1/12 of 60,that is 5 minutes of arc. These 12 divisions occupy the same space as 23
degrees on the main scale. Therefore each division of the vernier is equal to 1/12 of 23 or 1
11/12. Since 2 divisions on the main scale equals 2 degrees of arc, the difference between 2
divisions on the main scale and one division on the vernier scale is 2- 1 11/12 = 1/12= 5
minutes of arc. The accuracy of measurement will largely depend upon the skill of the user.
PROCEDURE:
ANGLE MEASUREMENT USING BEVEL PROTRACTOR:
1. The given work piece is cleaned before taking measurement.
2. The fixed blade of the bevel protractor is made to coincide with the reference
surface of work piece.
3. Move the movable blade of protractor to coincide with outer surface.
4. The angle between the blade is taken from protractor main scale and vernier scale
reading.
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Checking of angle between centre lines of holes:
1. A pin, which must be of good fit, is inserted in each hole (for which the angular
spacing is to checked) and rollers are placed in positions as shown.
2. The dimension M over the rollers is measured and from this, together with the
diameters of the pins ,rollers and shaft,the angle can be measured.
Referring to fig.
M d
Sin = ---------------
D + d
P + d
Sin = ---------------
D+ d
= 2(-)
Where,
M- Distance between the outer edges of the Rollers
P- Diameter of the Pins
d- Diameter of the Rollers
D- Diameter of the Shaft
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TABULATION:
ANGLE MEASUREMENT USING BEVEL PROTRACTOR:
WORKPIECE NAME OF
ANGLE
DESIGN VALUE
IN DEGREES
OBTAINED
VALUE IN DEGREES
DIFFERENCE IN
DEGREES
I a)
b)
c)
d)
II a)
b)
c)
d)
III a)
b)
c)
d)
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CHECKING OF ANGLE BETWEEN CENTRE LINES OF HOLES:
S.NO Diameter of the
Pins (P)
Diameter of the
Rollers(d)
Diameter of the
Shaft(D)
Distance between the outer edges
of the Rollers(M)
RESULT:
Thus using the bevel protractor, all the angles of the given-machined plate are found out
and compared with design values and errors are noted.
And the angle between the centre lines of holes is measured.
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PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No: Date:
HYSTERISIS CURVE OF A CANTILEVER BEAM
AIM
To draw the hysteresis curve of a wooden cantilever beam using a dial gauge setup.
PPARATUS REQUIRED
1. wooden cantilever beam
2. dial gauge
3. weights
DESCRIPTION:
The arrangement consists of a wooden beam of length 1metres with a loading
arrangement at its free end. The cantilever beam setup is kept on a reference surface. A dial
gauge with stands is used to measure the deflection of the beam.
PROCEDURE:
1. A wooden cantilever beam is loaded at its free end and a dial gauge which is also kept
on a reference surface measure the deflection of length of beam
2. The indicated readings of the dial gauge are noted down
3. After noting down the deflection for the applied load the load is increased in steps of
50 grams.
4. The Load is decereased in step of 50gms and the reading are noted down
5. The above procedure is repeated by keeping the dial gauge at different sections of the
beam
6. From the readings, a graph between load and deflection is ploted.
Least count = 1/100 = 0.01mm
Cantilever sensitivity =
Dial gauge sensitivity =
Overall sensitivity =
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` KONGU ENGINEERING COLLEGE
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Load in
gms
Deflection for loading in mm Deflection for unloading in mm
Section-I Section-II Section-I Section-II
1 2 1 2 1 2 1 2
Model Graph:
Result :
From the graph the hysteresis of the give wooden cantilever beam
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` KONGU ENGINEERING COLLEGE
(Autonomous)
PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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Ex.No: Date:
MEASURING CYLINDER AND CONE DIMENSIONS COORDINATE
MEASURING MACHINE
AIM:
To study the functions of different parts of CMM.
To study the conventions used for Machine Coordinate System and Work piece
Coordinate System.
To calibrate the probe tip at three different angles.
To check different dimensional attributes like circularity, cylindricity, flatness, run out,
etc and the corresponding tolerance values
APPARATUS REQUIRED
1.CMM unit
2.Job
DESCRIPTION & PRINCIPLE OF MEASUREMENT:
Co-ordinate Measuring Machine with its parts
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PERUNDURAI, ERODE - 638 052 DEPARTMENT OF MECHANICAL ENGINEERING
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It is used for geometrical feature measurement. The typical "bridge" CMM is
composed of three axes, X, Y and Z. These axes are orthogonal to each other in a typical
three dimensional coordinate system. Each axis has a scale system or encoder that indicates
the translation of the axes. The machine will read the input points from the touch probe by
touching the required location, as directed by the operator or programmer. The machine then
uses the X,Y,Z coordinates of each of these points to determine size and position of the job.
Then the measurands (e.g. length, diameter, angle, flatness, straightness etc.) can be
determined by those points. A coordinate measuring machine (CMM) is also a device used in
manufacturing and assembly processes to test a part or assembly against the design intent. By
precisely recording the X, Y, and Z coordinates of the target, points are generated which can
then be analyzed via regression algorithms for the construction of features. These points are
collected by using a probe that is positioned manually by an operator CMMs can be
programmed to repeatedly measure identical parts; thus a CMM is a specialized form of
industrial robot. In CMM there are mainly two major parts. There are structural system and
probing system. Machine structure, bridge, bearings for moving the bridge, granit table to
support the work piece, vibration isolation system and are included in the structural systems.
Air bearings are the chosen method for ensuring friction free travel. Compressed air is forced
through a series of very small holes in a flat bearing surface to provide a smooth but
controlled air cushion on which the CMM can move in a frictionless manner. In probing
system one touch trigger probe is attached to the Z-axis quill of the bridge. When probe is
rotated about X-axis it is then called as angle A, and when the probe is rotated about Z-axis, then
it is called as angle B.
PROCEDURE:
Job : Artefact supplied by TESA
1. Define plane, line and origin in manual mode.
2. Measure:
(a)Hole diameter, circularity of the Hole and Height,
(b) Cone angle and Diameter of the Cone
(c)Round slot
(d) Measurement of all the holes in polar array in manual mode
(e) Probe calibration is important while creating a new Part Program
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` KONGU ENGINEERING COLLEGE
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FEATURE DIMENSION 1 2 3 AVG VALUE
mm
Cylinder Diameter
Circularity
Cone
Height
Diameter
Cone angle
Sphere Diameter
REPORT SHOULD CONTAIN:
a. A neat sketch of CMM with proper mentioning of the machine and probe axes.
b. Calibration procedure of probe tip at angles: A__B__, A__B__ and A__B__ and show results.
c. Comment on variation of the standard deviation errors (if any) in previous results.
d. Check dimensional attributes and tolerances for the job provided.
e. Comment on why a sphere has been chosen for the tip.
f. What is the material for probe tip and why is it chosen?
g. Why is it better to use a bigger diameter tip for measurement?
h. What is the principle of slide-guide mechanism for all the three machine axes?
PRECAUTIONS:
! Never touch the granite base on the machine for accuracy issues.
! Do not touch the Axis slides, probe head/tip, and the guides.
top related