8/12/2019 ME2308 Lab

1/39

ALAMEEN ENGINEERING COLLEGEKarundevanpalayam, Erode - 63810

!epar"men" o# Me$%an&$al En'&neer&n'

ME2308- Metrology and Measurements Lab

Prepared by :N. Rajkumar AP/Mech

M. Veerakumar AP/Mech

Name ( )))))))))))))))

Re' No ( )))))))))))))))

*ran$% ( )))))))))))))))

+ear eme."er ( )))))))))))))))

8/12/2019 ME2308 Lab

2/39

Mechanical Comparator

1. CALIBRATION O PR!CI"ION M!A"#RIN$ IN"TR#M!NT"

8/12/2019 ME2308 Lab

3/39

Aim%

To study and calibrate the precision measuring instruments like Vernier caliper,Micrometer, and Dial gauge.

Apparatu& Re'uire(%Surface plate, Vernier caliper, Micrometer, Dial gauge, and Slip gauges.

"peci)ication%Vernier caliper Range: . !:Micrometer Range: . !:Dial gauge Range: . !:

"tu(*%1.+ Vernier caliper%

The Vernier caliper has one " # shaped frame $ith a fi%ed &a$ on $hich Vernier scale isattached. The principle of Vernier is that $hen t$o scale di'isions slightly different in si(es can beused to measure the length 'ery accurately.

east !ount is the smallest length that can be measured accurately and is e)ual to thedifference bet$een a main scale di'ision and a Vernier scale di'ision.

*+ST ! - T / 0 Main scale di'ision 1 0 Vernier scale di'ision

#&e&%2t is used to measure the e%ternal diameter, the internal diameter and the length of the

gi'en specimen.

,.+ Micrometer%The micrometer has an accurate scre$ ha'ing about 03 to 43 threads5cm and re'ol'es in a

fi%ed nut. The end of the scre$ is one tip and the other is constructed by a stationary an'il.

*+ST ! - T / Pitch scale di'ision 5 umber of threadsPitch scale di'ision / Distance mo'ed 5 number of rotation

#&e&%utside micrometer is used to measure the diameter of solid cylinder.

2nside micrometer is used to measure the internal diameters of hollo$ cylinders andspheres.

-.+ ial au e%

The dial gauge has got 4 hands. The short hand reads in mm. ne complete re'olution of

long hand reads one mm. The plunger of the dial gauge has to be placed on the surface $hosedimension has to be read.

east !ount / ne di'ision of the circular scale $ith long hand.

#&e&%2t is used as a mechanical comparator.

0.+ "lip au e&%

8/12/2019 ME2308 Lab

4/39

They are rectangular blocks hardened and carefully stabili(ed. The surfaces are highly polished to enhance $ringing. 2t is used as a reference standard for transferring the dimensions ofunit of length from primary standard. 2t is generally made up of high carbon, high chromiumhardened steel.#&e&%

These are accurate and used as comparator.

.+ "ur)ace plate%The foundation of all geometric accuracy and indeed of all dimensional measurement in

$orkshop is surface plate. 2t is a flat smooth surface sometimes $ith le'eling scre$s at the bottom.

#&e&%2t is used as a base in all measurements.

Proce(ure or Cali2ration%0.6 The range of the instruments is noted do$n.4.6 7ithin that range, slip gauges are selected.8.6 The measuring instrument is placed on the surface plate and set for (ero and the slip

gauges are placed one by one bet$een the measuring points 9&a$s of the instruments.6.6 The slip gauge 9actual6 readings and the corresponding 9obser'ed6 readings in the

measuring instruments are noted do$n and tabulated.

S. o

Slip;auge

Reading 1 9+ctual62n mm

Precision Measuring 2nstruments Reading 9 bser'edl6 in mm

Vernier !aliper Micro Meter Dial ;auge

MSR 9mm6

VSR 9di'6

TR 9mm6

*rror 9mm6

PSR 9mm6

8/12/2019 ME2308 Lab

5/39

Re&ult%

The precision measuring instruments are studied and calibrated.!alibration graphs are then dra$n for all measuring instruments bet$een

0.6 +ctual 'alue and bser'ed 'alue.4.6 +ctual 'alue and +bsolute error.

8/12/2019 ME2308 Lab

6/39

,. M!A"#R!M!NT O IM!N"ION" O A $IV!N "P!CIM!N #"IN$ "LIP $A#$!

8/12/2019 ME2308 Lab

7/39

Aim%

To !heck the Various Dimensions of a Part -sing Slip ;auge

Apparatu& Re'uire(% . Surface Plate, Dial ;auge 7ith Stand, Slip ;auge, Part9Specimen6"peci)ication% Dial ;auge : Range:======= .!. :========mm

Proce(ure%

0. The part $hose dimensions are to be measured is placed on the surface plate.

4. The spindle of the dial gauge is placed o'er the part and dial gauge is fi%ed on the standsuch that the short and long handoff the dial gauge so$s (ero readings.

8. Then the part is remo'ed and the slip gauges are placed one o'er another on the

surface plate belo$ the spindle of the dial gauge until the hands of the dial gaugedeflect from (ero reading.

. This ensures that the dimensions achie'ed by slip gauges and the part is same.

>. The re)uired dimensions of the part is measured by finding out the total

8/12/2019 ME2308 Lab

8/39

$ear Tooth Vernier

-. M!A"#R!M!NT O $!AR PARAM!T!R" #"IN$ $!AR TOOT3 V!RNI!R

8/12/2019 ME2308 Lab

9/39

Aim%To measure gear parameter by gear tooth Vernier.

Apparatu& re'uire(%

;ear tooth Vernier, ;ear specimen.

"peci)ication%

;ear tooth Vernier: Range /

8/12/2019 ME2308 Lab

10/39

TR2+ -T S2D* D2+M*T*R "D# mm

0

4

8

>

Measurement of +ddendum and !hordal 7idth

Trial !hordal addendum# d# mm !hordal $idth "$# mm+ctual . Theoretical +ctual Theoretical

0

4

8

>

?

Re&ult%Thus the chordal thickness and addendum of gear are measured using gear tooth Vernier.

The actual 'alues are 7 /

D /

8/12/2019 ME2308 Lab

11/39

04a+. !T!RMINATION O TAP!R AN$L! B5 #"IN$ "IN! BAR

8/12/2019 ME2308 Lab

12/39

+2M:

To measure the taper angle of the gi'en specimen using sine bar method.

+PP+R+T-S R*E-2R*D:

0. Sine bar . micrometer

4. Slip gauge set >. surface plate

8. Dial gauge $ith ?.Vernier caliper stand

F RM- +:

Sin G / h 5

7here,

< A

8/12/2019 ME2308 Lab

13/39

ength of the sine

8/12/2019 ME2308 Lab

14/39

0 42+.TOOL MA6!R7" MICRO"COP!

+2M:

8/12/2019 ME2308 Lab

15/39

To determine the ma&or and flank angle for the particular scre$.

+PP+R+T-S R*E-2R*D:

Tool maker#s microscope 7ork piece

PR !*D-R*:

0. S$itch on the main.

4. S$itch on the micros scope lights.

8. Select the capacity of the lens for precision operation.

. Place the ob&ect on the class table to get the clear image rotate the $heel pro'ided at

the light side.

>. +fter getting the clear image, locate the cross$ire at the initial point on the image.

o$ note do$n the micrometer reading.

?. Mo'e the cross $ire from initial point to the finial point on the image, $hich is to be

measured. ote do$n the micrometer reading, this operation is done by using

micrometer.

. o$ the different but $hen the initial and the finial reading i.e. distance tra'eled

gi'es the si(e of the ob&ect.

J. ;raph can be plotted actual micrometer reading 's. K of error.

T+@- +T2 :

8/12/2019 ME2308 Lab

16/39

Profile pro&ector micrometer reading *rror Sl. +ctual micrometer

9+AD6 K error 2nitial9@6Final 9c6 Difference o reading in mm 9+6

mm mm b5$ @L ! 9D6 2n mm

F2 D T

8/12/2019 ME2308 Lab

17/39

2 STR-M* T @+S*D +S*R:

80. *%plain ho$ the thickness of an ob&ect is measured using a laser distancemeasuring instrument.

84. *%plain ho$ profiles are checked using laser 'ie$ers.

88. *%plain the interferometic measurement of angle.

M+!

8/12/2019 ME2308 Lab

18/39. A#TOCOLLIMATOR

8/12/2019 ME2308 Lab

19/39

+2M:

To test the flatness of the gi'en surface.

M+2 P+RTS:

0. !ollimator -nit4. @ase

8. Plain Reflector. ptical Source

+PP 2!+T2 :

Measurement in glass shop, checking the straightness and flatness, checking s)uare andVAblock, checking deflection of the structure under the load measuring tapes, checking the angleof small castings.

SP*!2F2!+T2 :

b&ecti'e focal length /833mmb&ecti'e clear aperture /4>mm

@arrel diameter /8Jmm

@arrel length /433mm

*yepiece magnification /03O

Measuring range /4> minutes

Read out /direct gratitude +TP

Dimensions of base /Solid lagged !.2 base 9 >mmO4>3mm6

Flatness of base /+s per 2S2 stander#s

8/12/2019 ME2308 Lab

20/39

PR !*D-R*:

0. S$itch on the light and obser'e the measuring gratitude through eyepiece.4. The smallest di'ision of liner scale is 0 minute.8. @ring the plain reflector in front of autocollimator to get a reflected.

. Depending upon 'ariation in surface position of target $ill change on measuring scale.>. There upon the position of intersection point of cross bar line $ill measuring gratitude

is the de'iation in minute.?. -sing micrometer pro'ided for eyepiece $e can measure the function upto 03 seconds.

T+@- +T2 :

Sl. o Test surface length9mm6 +utocollimator reading9mm6

8/12/2019 ME2308 Lab

21/39

M+!

8/12/2019 ME2308 Lab

22/39

8/12/2019 ME2308 Lab

23/39

8. LOATIN$ CARRIA$! MICROM!T!R

4B!NC3 MICROM!T!R+

+2M:

To measure the ma&or diameter of scre$ thread using floating carriage micrometer.

PR !*D-R*:

!lear all the parts $ith tissue paper or soft cloth. Put the base 9+6 on the form ele'ationtable on surface plate le'el the machine $ith the help of scre$ 9*6 in such a $ay that the floatingtop remains steady at any position $ith out gra'itational motion.

Put floating top 9 6 on the carriage $ith t$o balls bet$een the t$o stopper fins on oneside V groo'e of carriage 9@6 and floating top 9!6. Put one ball on other V groo'e on other sideof floating top bet$een the stopper pins.

2nsert the micrometer9F6 pro'ided $ith machine in one side of the floating top nearer toobser'er and tight le'er9N6 and scre$ pro'ided on floating top 9!6. 2nsert the " # indicator 9!6 onthe other side of the V groo'e on floating and tight the le'er and scre$.

o$ the machine is ready to take the readings.

M*+S-R*M* T + D !+ !- +T2 :

Ma&or diameter measurement

The dia of the setting master on a cylinder should be nearly same as the dia of the threadgauge. The ad'antage of using setting master is it gi'es similarly of contact of an'ils and radiuserror in measurement the setting is held bet$een the centers. The master cylinder is then replaced

by the threaded $ork piece on threaded gauge and then second reading is taken.

DADiameter of setting master.R 0AMicrometer reading o'er setting master.

R 4AMicrometer reading of threaded $ork piece or gauge.

Then,

Ma&or diameter DC different bet$een R 0 and R 4 the Cor 1is determined by relati'e si(eof master and $ork piece.

8/12/2019 ME2308 Lab

24/39

T+@- +T2 :

StandardF!M reading F!M reading Difference +ctual reading

S . o for standard for the scre$dimension

piece 9+6 thread9@6 9+A@6 SD 9+A@6

F R!*:

*%plain $ith a diagram a pendulum scale of multile'er type.*%plain the method of measuring force using a strain gauge load cell.

*%plain the method of measuring force using a hydraulic, pneumatic load cell.

T RE-*:

*%plain the measurement of tor)ue by

9i6 ptical torsion meter 9ii6 slotted discs 9iii6 rotating shafts.

P 7*R:

*%plain the measurement of po$er by

9i6 Prony brake 9ii6 fluid friction dynamometers 9iii6 *ddy currentdynamometer

R*S- T:

Thus the ma&or diameter of the scre$ thread is measured by usingfloating carriage micrometer .

8/12/2019 ME2308 Lab

25/39

9. T!MP!RAT#R! M!A"#R!M!NT

Aim% To measure the temperature using copper constantan thermo couple.

Apparatu& Re'uire(%

0. Thermo couple4. Temperature measuring setup.8. 2ce cubes.

Proce(ure%

0. !onnect the thermocouple supplied at the impute terminal if copper constantanThermocouple is used. !opper $ire must be connected to the terminal and constantan $ire to 1'e terminal.

4. 2mmerse the &unction of thermocouple in ice and ad&ust the meter reading at 3Q !using potentiometer.

8. 2mmerse the &unction of thermocouple in boiling at BJQ ! by using potentiometer marked ma%. . Repeat the procedure for 4 to 8 times.

Tabulation:

Sl.no +ctual temperature !Q 2ndicated temperature !Q0

4

8

>

?

J

8/12/2019 ME2308 Lab

26/39

B

03

Re&ult% Thus the temperature is measured using thermocouple.;raph:

2ndicated Temperature Vs +ctual Temperature

8/12/2019 ME2308 Lab

27/39

:. M!A"#R!M!NT O I"PLAC!M!NT #"IN$ LV T

Aim% To measure the displacement using VDT.

Apparatu& Re'uire(%

0. VDT4. Micrometer

Proce(ure%

0. Plug the po$er chard to +! main 483'5>3. +d&ust the calibration point by rotating !+ knob so display should read03.33 9i.e.6 ma%imum ranges.

?. +gain keep the R*D5!+ s$itch at read position and connect the VDTcable to instruments.

. Mechanical (ero by rotating the micrometer. Display $ill read (ero this isfull balancing.

J. ;i'e displacement $ith micrometer and obser'e the digital reading.B. Plot the graph of micrometer reading.

Sl.noPush side Pull Side

Micrometer Reading 9mm6

2ndicated Reading9mm6

Micrometer Reading 9mm6

2ndicatedReading 9mm6

0

4

8

>

Re&ult%

Thus displacement has been measured using VDT.;raph:

2ndicated reading Vs Micrometer reading

1;. ORC! M!A"#R!M!NT Aim%

8/12/2019 ME2308 Lab

28/39

To measure the force using load cell.

Apparatu& Re'uire(%

0. Pro'ing Ring4. oad cell8. Force indicator

. scre$ &ack >. Dial gauge.

!apacity of pro'ing Ring /4.> .

e&cription :

Force is one of the ma&or deri'ed parameter ha'ing fundamental dimension ofmass length and time. 2t is a 'ector )uantity $hich, $hen applied result in a change ofmomentum in a body. @asically mechanical force is created due to 'ariation of started

potential energy.

This is different types of load cell like column type, shear type, sAtype, andcompression type. 2n this setup, sAtype load cell is pro'ided.

Proce(ure%

< *nsure that pro'ing ring along $ith load all is perfectly in 'ertical position. O !heck and ensure that the a%is of scre$ &acks perfectly aligned $ith load cell. O *nsure that load cell $ith socket is connected to the rear side of the loadindicator. O +pply a small load $ithout any slip in the system. O ote do$n the reading of dial gauge of force indicator.

Ta2ulation %

Sl.no +ctual load applied 9kg6 Deflection 9di'6

0

4

8

>

?

8/12/2019 ME2308 Lab

29/39

J

B

03

0 di'ision / 3.334mm

Re&ult% Thus the force measurement has been measured using load cell.;raph: Deflection Vs +pplied load

11. TOR=#! M!A"#R!M!NT Aim%

To measure the tor)ue using shear type load cell.

8/12/2019 ME2308 Lab

30/39

Apparatu& Re'uire(%

0. Tor)ue measurement e)uipment4. Stand8. le'er

. stain gauge>. 7eight.

ormula #&e(%

!alculated Tor)ue / oad % Distance 9kgAm6

e&cription%

Tor)ue is the tangential force to set a body in rotation. 2t is represented as a'ector of a force for a rigged body undergoing force rotation about a single a%is. Tor)ue / D , D / Moment of inertia of body about the a%is. / +ngular acceleration.

Thus tor)ue is the essential tensional t$isting about its a%is of rotation. 2n this

setup shear type load is used to measure the tor)ue a in'erse method of measuring theload $ith the output immune to side load and bending moment is based on measurementof shear components. The load cell is balancing a beam supported on both ends.

Proce(ure%

0. Fi% the main frame of transducers rigidity.4. !onnect the cantile'er beam $ith $eight pan.8. !onnect transducer $ire socket to rear side of indicator.

. !onnect digital indicator at 483V, +! supply.>. Set (ero on indicator, by (ero ad&ust pan pro'ides indicator.?. o$ apply the load gradually and note do$n reading in up$ard L

do$n$ard trend.

i&tance% 1 meter

Sl.no 7eight added 9 g6 bser'ed tor)ue9 gAm6!alculated Tor)ue

9 gAm604

8

>?

JB

03

8/12/2019 ME2308 Lab

31/39

i&tance% ;. meter

Sl.no 7eight added 9 g6 bser'ed tor)ue9 gAm6!alculated Tor)ue

9 gAm6048

>?

JB

03

Mo(el Calculation%

!alculated Tor)ue / oad % Distance 9kgAm6

Re&ult% Thus measurement of tor)ue using shear type load cell has been carried out.;raph:

bser'ed tor)ue Vs !alculated tor)ue

1,. M!A"#R!M!NT O VIBRATION PARAM!T!R" #"IN$VIBRATION "!T #P

Aim%

8/12/2019 ME2308 Lab

32/39

To study the 'arious parameters in'ol'ed in the 'ibrations of a gi'en system.To plot the characteristic cur'es of the gi'en specimen

Apparatu& Re'uire(%

Vibration e%citer Vibration pickAupVibration analy(er Po$er amplifier

scillator

e&cription%

The mechanical 'ibration, if not $ithin limits may cause damage to the materials,structures associated $ith it.

Vibration e%citer is an electrodynamic de'ice. 2t consists of a po$erful magnet placed centrally surrounding $hich is suspended the e%citer coil. This assembly is

enclosed by a high permeability magnetic circuit.

7hen an electrical current is passed through the e%citer coil, a magnetic field iscreated around the coil resulting in the up$ard or do$n$ard mo'ement of the suspendedcoil depending upon the direction of the current flo$ in the coil. Thus controlling thefre)uency of the coil current, the fre)uency of 'ibration is controlled.

Po$er amplifier is the control unit for the e%citer.

Pie(o 1 electric crystals produce an emf $hen they are deformed. This output emf may be measured to kno$ the 'alue of applied force and hence the pressure.

+ pie(o 1 electric material is one in $hich an electric potential appears acrosscertain surfaces of a crystal of the dimensions of the crystal are charged by theapplication of a mechanical force. The effect is re'ersible.

!ommon pie(o 1 electric materials include )uart(, Rochelle salt, lithium sulphateetc.,

Caution%

Do not remo'e the fuse cap $hile po$er chord is connected to 483V +! mains

Proce(ure%1. !onnect po$er amplifier output to 'ibration e%citer.,. Place the 'ibration pick up on 'ibration e%citer spindle.-. !onnect 'ibration pick up cable to 'ibration analy(er sensor socket.0. select the range 3A033 by t$o $ay s$itch.

8/12/2019 ME2308 Lab

33/39

. ote do$n the displacement, 'elocity and acceleration from 'ibrationanaly(er.

8. Similarly noted abo'e parameters in fre)uency range of 3A0333

8/12/2019 ME2308 Lab

34/39

Thermocouple

*)ui'alent circuit

Solution circuit

8/12/2019 ME2308 Lab

35/39

Time constant

>. Thermocouple Temperature Mea&urement

Aim%To study the current flo$ and 'oltage de'eloped is directly proportional to the

temperature in the thermocouple of a gi'en system.

Apparatu& Re'uire(%

Thermocouple transducer Digital multiAmeterThermocouple $ith metallic sheath.

ettle and t$o mugs.

Proce(ure%

i. Thermocouple cali2ration%06 !onnect the thermocouple terminals to the digital multimeter.46 *nsure you connect the positi'e terminal and negati'e terminal to the

corresponding terminals on the multimeter.86 Set the multiAmeter to the 433 mV range.

6 Prepare a mug of cold $ater from the tap.>6 @oil the $ater in the kettle pro'ided. Make sure it is boiling before you

s$itch it off.?6 Place thermometer in the $ater.

6 Place the thermocouple in the $ater as $ell.J6 Take a reading of the thermometer and the multimeter 'oltage and record it in the

table belo$. Nou need to take as many pairs of readings a possible, co'ering thetemperature range from J3 Q! to 43 Q!

ote: To speed up change in temperature, you can pour some of the cold $aterinto the hot $ater mug. 7ait for > seconds for the temperature to settle and takereading.

B6 Repeat the last step a number of times until the temperature of the $ater are near room temperature or until the thermocouple 'oltage is (ero.

036 Plot the temperature against the 'oltage on a scatter diagram. Dra$ the bestline fit and find the relationship bet$een the t$o readings.

ii. T*pe thermocouple cali2ration%Repeat the Procedure again using Atype thermocouple

8/12/2019 ME2308 Lab

36/39

Re&ult& )or Thermocouple

".No Temperature 4?C+ Volta e rea(in 4mV+

Mea&urin time con&tant&

i. Time con&tant )or thermocouple in @ater%06 Place the thermocouple in the cold $ater. Record the final 'oltage 'alue at $hich

it settles.46 Remo'e the thermocouple and place it in the hot $ater mug and keep it.

Record the 'oltage that it sho$s.86 The difference bet$een the t$o 'oltages $ill be the step function it is e%posed

to $hen mo'ing from one to the other. The time constant $ill be the time takesit to drop to the 8 K of the difference bet$een the t$o 'alues.

6 Prepare a stop$atch to measure the time.>6 +t the same time, start the stop$atch and mo'e the thermocouple from the hot

$ater to the cold $ater.?6 ote $hen the 'oltage drops to 8 K of the difference and check the time.

6 This is the time constant for the thermocouple in $ater.

ii. Time con&tant )or thermocouple in air%06 Place the thermocouple in air. 7ait long enough for it to settle.46 Record the final 'oltage 'alue at $hich it settles.86 Remo'e the thermocouple and place it in the hot $ater mug and keep it.

Record the 'oltage that it sho$s.6 The difference bet$een the t$o 'oltages $ill be the step function it is e%posed

to $hen mo'ing from one to the other. The time constant $ill be the time takesit to drop to the 8 K of the difference bet$een the t$o 'alues.

>6 Prepare a stop$atch to measure the time.?6 +t the same time, start the stop$atch and mo'e the thermocouple from the hot

$ater to the air. ote $hen the 'oltage drops to 8 K of the difference andcheck the time. This is the time constant for the thermocouple in air.

8/12/2019 ME2308 Lab

37/39

Re&ult%

Mechanical comparators:-

Dial ;auge

8/12/2019 ME2308 Lab

38/39

1-. ! P!RIM!NT ON M!C3ANICAL COMPARATOR

Aim%

To setting the mechanical comparator and compare the reading in gi'enspecimen.

Apparatu&%

Dial indicator, slip gauges, specimen, surface plate etc.

Proce(ure%0. First decide the dimension of specimen to be compared against the standard.

4. ;et the std.9desired6 'alue of that dimension from design manual.

8. @uild up a slip gauge bar of standard 'alue by $ringing.

. Place the slip gauge bar, specimen and dial indicator on the surface plate assho$n in figure.9a6.

>. The pointer of dial indicator is made to touch the top surface of slip gauge bar.?. +d&ust the dial indicator to (ero reading.

. Then pointer is made to touch the top surface of specimen as sho$n in figure.9a6.

J. ote the dial reading, it gi'es the de'iation of specimen dimension fromstandard 'alue.

B. Take minimum 8 reading for one dimension at different position as sho$n infigure.9b6.

03. Repeat the same procedure for different $orkpieces.

8/12/2019 ME2308 Lab

39/39

O2&er ation Ta2le%

Standard !omparator Reading +'g.@ 75P Dimension 9De'iation6

0 4 8

0

4

8

Re&ult%

Thus the inspection of mechanical comparator $as studied and compared thei' i