1. CALIBRATION OF VERNIER CALIPER

AIM:

To calculate the given vernier caliper and to measure the given dimension of the specimen.

APPARATUS REQUIRED:

1. Vernier Caliper2. Surface Table3. Slip Gauges

VERNIER CALIPER:

The principle of vernier caliper is that when two scales or division size are used. The difference between them can be utilized to enhance the accuracy of measurement.. The vernier caliper essentially consists of two steel rules and these can be slide along each other.

TABULAR COLUMN: L.C=0.02 mm

Sl.No

Slip Gauge Reading (mm)

Observed Reading

MSR VSC*LC

Measured Reading

(mm)

Error(mm)

1

Calculation Of Least Count:

Least Count =1MSD-1VSD

1MSD =1mm

50 VSD =49 mm

1VSD =0.98 mm

Least Count =1-0.98

= 0.02mm

PROCEDURE:

1. Calculate the least count of instrument.2. Check the zero error.3. Measure the specimen note down the main scale reading or the head scale

reading.4. Note down the vernier or head scale coincidence with main or pitch scale

division.5. A graph is drawn using slip gauge value in X-axis and measured value in Y-

axis.

RESULT:

Thus the accuracy and error of the vernier caliper is found.

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2. CALIBRATION OF MICROMETER

AIM:

To calculate the given micrometer and to measure the given dimension of the specimen.

APPARATUS REQUIRED:

1. Micrometer2. Surface Table3. Slip Gauges

TABULAR COLUMN: L.C=0.01 mm

Sl.No

Slip Gauge Reading (mm)

Observed Reading

MSR HSC*LC

Measured Reading

(mm)

Error(mm)

3

Calculation Of Least Count:

Least Count (L.C) =Pitch Scale/ No.of division on the head scale

= 0.5/50

= 0.01mm

PARTS OF MICROMETER:

1. Frame2. Anvil3. Spindle4. Spindle Lock5. Barrel6. Thimble7. Ratchet Stop

PROCEDURE:

1. Calculate the least count of instrument.2. Check the zero error.3. Measure the specimen note down the main scale reading or the head scale

reading.4. Note down the head scale coincidence with main or pitch scale division.5. A graph is drawn using slip gauge value in X-axis and measured value in

Y- axis

RESULT:

Thus the accuracy and error of the micrometer is found.

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3. CALIBRATION OF DIAL GAUGE

AIM:

To find the accuracy and standard error of the given dial gauge.

APPARATUS REQUIRED:

1. Dial Gauge2. Surface Table3. Slip Gauges

TABULAR COLUMN: L.C=0.01 mm

Sl.No

Slip Gauge Reading (mm) X

Dial Gauge Reading (mm) X

Error (mm)(X-X) (X-X)2

5

PROCEDURE:

1. The dial gauge is fixed to the stand rigidly and placed on the surface plate.2. The plunger of the dial gauge is set to first touch the upper surface of the

standard slip gauges and indicator is set to zero.3. Then the plunger is raised by pulling the screw above the dial scale.4. Another slip gauge is placed on the standard slip gauge.5. The plunger touches the standard slip gauge.6. The reading on the dial scale is noted.

The standard error of the dial gauge = ∑(X-X)2 1/2

(n-1)

X -Slip Gauge ReadingX - Dial Gauge ReadingN - No. of Reading

RESULT:

Thus the accuracy and standard error of the dial gauge is found.

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4.MECHANICAL COMPARATOR

AIM:

To check the dimension of the given specimen using mechanical comparator.

APPARATUS REQUIRED:

1. Comparator Stand2. Dial Gauge3. Slip Gauge4. Surface Table

TABULAR COLUMN: L.C=0.01 mm

Sl.No

DialGauge Reading (mm)

Work Piece Size

(mm)

Average Size(mm)

Status

7

PROCEDURE:

1. The comparator stand is placed on the surface.2. The comparator stand is set by datum.3. The basic dimension of the specimen is set below the datum and

mechanical comparator should be load.4. Now the comparator is calculated by checking the given dimension.5. The specimen is placed one by one and find five readings.6. Finally the status of the specimen is calculated.

Actual Size of Specimen =30mm

Tolerance =30± 0.05mm

RESULT:

The dimensions of the given specimen using Mechanical comparator is calculated.

Basic Dimension

Tolerance

Actual Size of Specimen

5.DETERMINATION OF TAPER ANGLE BY SINEBAR METHOD8

AIM:

To measure the taper angle of the given specimen using sinebar method.

APPARATUS REQUIRED:

1. Sinebar2. Slip Gauges3. Dial Gauge4. Surface Plate

DESCRIPTION:

The sinebar principle uses the ratio of the length of two sides of a right triangle. It may be noted that device operating on sine principle are capable of ‘self generation’. The measurement is restricted to 45⁰ from accuracy point of view. Sinebar itself is not a measuring instrument.

TABULAR COLUMN: L.C=0.01 mm

Sl.No

Slip Gauge Combination (mm)

Dial Gauge Value(mm)

Final Reading(mm)

Difference

9

PROCEDURE:

1. The dial gauge is fixed on the magnetic stand and placed on the surface plate and the parallelity of the sinebar is checked.

2. The given specimen is placed above the sinebar and dial gauge is placed on top of the specimen and adjusted for zero deflection.

3. Then the front end of sinebar is raised with slip gauge until the work surface is parallel to the datum surface.

4. The parallelity is checked using dial gauge.5. Then the distance between the centers of the sinebar rollers is

measured as ‘L’.6. The height of the slip gauge is noted as ‘H’.7. The included angle of the specimen is noted.

FORMULA: Sinθ = X/L

X = Final height of slip gaugeL = Length of sinebar

RESULT:

Thus the taper angle in given bar is found.

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5.TREAD PARAMETERS MEASUREMENT USING PROFILE PROJECTOR.

AIM:

To find the parameter of the given thread of screw.

APPARATUS REQUIRED:

1. Profile Projector2. Trace Paper3. Screw

TABULAR COLUMN: L.C=0.01 mm

Sl.No

Parameters Initial Reading Final Reading(mm)

Correct Reading

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PROCEDURE:

1. The specimen is placed on the work table centre and the projector is switched on.

2. The magnification lens is placed on the lens slot.3. The thread is focused clearly by adjusting focusing knob to view the shadow

on the screen clearly.4. Trace paper is placed on the shadow profile is traced then the error in pitch

is determined.5. The major diameter and minor diameter of pitch of the tread are measured

from the tracing sheet.

RESULT:

Thus the parameter of the given screw are determine using profile projector.

1. Major Diameter2. Minor Diameter3. Pitch

6. GEAR TOOTH MEASUREMENT USING PROFILE PROJECTOR.

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AIM:

To draw the profile of the given gear and to measure the tooth thickness of the gear.

APPARATUS REQUIRED:

1. Profile Projector2. Trace Paper3. Gear4. Vernier Caliper

TABULAR COLUMN: L.C=0.01 mm

Sl.No MSR (mm) VSC*LC (mm) Total reading

(mm)

13

FORMULA:

1. Module (M) =Outer Dia/ Z+2 Z = No. of tooth

2. Theoretical tooth thickness (T) = m.z. sin(90/Z)

3. Height (H) = M[1+Z/2(1-cos(90/Z)]

PROCEDURE:

1. The specimen is placed on the work table centre and the projector is switched on.

2. The magnification lens is placed on the lens slot.3. The gear is focused clearly by adjusting focusing knob to trace the shadow

on the gear clearly.4. Trace paper is placed on the shadow profile is traced.

RESULT:

Thus the profile of the given gear are drawn and the thickness of the tooth is measured using profile projector.

8. PRONY BRAKE DYNAMOMETE.

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AIM:

To calculate the torque, break power efficiency of the motor using prony brake dynamometer.

APPARATUS REQUIRED:

1. Prony brake dynamometer2. Tachometer3. Stop watch4. Digital ammeter5. Weight

TABULAR COLUMN:

Sl.No

Load on

hanger (w)

Speed

(m)

Time for n=1

revolution (t)

Torque (T)

Output

Input

Efficiencyη%

Current (I)

Voltage

(V)

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FORMULA:

1. Input power = (n*3600*1000)/(Emc*t) Watts

Where Emc = Energy meter constant in rev/kw hr

T = Time taken for one revolution of energy meter disc

N = no of revolution

2. Torque (T) =(S1~S2)*9.81*R (N-m)

R = 0.5m radius of brake drum mm(S1~S2) = Load applied in kg

3. Output Power = 2Πnt/60 Watts

N = Speed of the motorT = Torque in mm

4. Efficiency (η) = (Output)/(Input)*100

PROCEDURE:

1. It is confirmed that there is no weight on pulley and motor in ON position.2. The speed of motor / voltmeter and ammeter reading and time revolution

of energy meter disc are noted.3. Load is applied on pulley by switching hand screw the spring balance

reading is noted along with other reading on the control panel.4. The load is raised for each and setting the same procedure is followed.5. The input power, output power, torque and efficiency are calculated.

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RESULT:

The torque, output power of the motor is calculated using prony brake dynamometer.

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9.CALIBRATION OF THERMO COUPLE AND MEASUREMENT OF THERMOCOUPLE.

AIM:

To calibrate the given chromium/ aluminum iron thermocouple of platinum resistance thermocouple.

APPARATUS REQUIRED:

1. Thermometer2. Thermocouple3. ICC water

TABULAR COLUMN:

Calibration of standard: ICC

Actual temperature : 0⁰c

Sl.No Measured Device Indicated Temperature0⁰c

Error

18

TABULAR COLUMN:

Calibration of standard: Boiling water

Actual temperature :100⁰c

Sl.No Measured Device Indicated Temperature

0⁰c

Error

PROCEDURE:

1. Initially all circuit are kept at iron temperature.2. Thermometer and resistance thermometer are connected for the regulated

power supply.3. After being allowed to they are powered in the ice and indicator

temperature is noted.4. A graph is plotted between indicated temperature and actual temperature.

RESULT:

Thus the given thermocouple has calibrated and the non-temperature was found.

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DEPARTMENT OF MECHANICAL ENGINEERING

ME 1322 – METROLOGY AND MEASUREMENT LAB MANUAL

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