Mechanical measurements and metrology Question Papers


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Mechanical measurements and metrology Question Papers

  1. 1. O6ME42B Fourth Semester B.E. Degree Examination, May/June 2010 MechanicalMeasurementsandMetrology Time: 3 hrs. Max. Marks:100 Note: Answer any FIVE full questions, selecting at least TWO questions from each part qi 1 a. What is metrology? State its obj.",rffi o (06 Marks) o c, d b. Define the following: (09 Marks) a i) Line standard ii)-End standard iii) Waveleneth s]an{1{t ^ € o c. What is wringing? Buitd the following dimensions usirg M-112 set: st c) i)33.4s65 ii) 87.102s. (05 Marks)3R9p= 2a. Distinguish between tolerance and allowance. 04 Marks); b. Explai-ntheprincip1esofinterchangeabilityandselectiveassemblyHoJh c. Orirr-i"" tire a"toat dimensions for a hole-shaft pair designated -x Z8,Hilfy. Dimension 28 falls in the range of 18 to 30 mm. Fundamental deviationior f shaft is -5.5D0al,ITt= l6iao" c0p.HN drf *a n* :2li.folerance unit i:0.45(D)r/3 + 0.001D (microns). (10 Marks)9ilotr€gtri 3a. Sketch and explain the following comparators:o> i) Zeiss optimeter ii) Solex comparators (12 Marks) 3e b. With a neat figure, explain the principle of sine bar (04 Marks) 4(d c. Build the following angles: bu 48 i) 49 36, ii) 35 32, 36" (04 Marks) (6O Explain how the straightness can be measured by using an autocollimator boe (08 Mar*s) cd(6!b 4 a. expUin the 3 wire method of measuring the effective diameter of a screw thread (0E Marks) ao 9s b.t(d c. Briifly explain the working of a tool-makers miuoscope. (04 Marks) PART _ B a& (05 Marks) oj 5a. With a suitable example, explain the generalized measurement slstem. b. Define the following terms: i) Accgracy ii) Precision iii) Calibration iv) Hysteresis. OE (08 Marks) te =9 !!j) c. Witf, u blotk diagram, distinguish betrveen primary and secondary transducers. (06 Marks) 3E o.i >.! the inherent bDv cb0 6a. what is the requirement of an intermediate modiffing device? Explain problems, with a mechanical system. (08 Marks) a8 tr> (06 Marks) b. With a neat figure, explain the ballast circuit. o (06 Marks) ch c. Explain the working of a CRO. oe -: e.i 7a. Sketch and explain the working of a platfolm balance, (06 Marks) 6) (08 Marks) Z o b. With a neat figure, explain the prony brake dynamometer. (06 Marks) cl c. Discuss the working of Mcleod gauge- r E 8a. What is a thermocouple? State and explain the laws of thermocouple. (08 Marks) (08 Marks) b. Discuss the construction and working of an optical pyrometer. (04 Marks) c. What is a strain gauge? ***+*
  2. 2. 5 TP42B t1 FourthSemesterB.E.DegreeExamination,Dec.0TlJan.08 Metrology and Measurements Max Marks:100Time:3 hrs. Noteztr.AnsweranyF|VEfuttquestionschoosingutleastTWo questions from each Part 2. Draw nnit ,kut"hes wherever required (05 Marks) of metrologyla. Define Metrology Listout the objectives r ---r ^+^.^r^*re standard? (05 Marks) b What are the advantaglt *rt.iength standard over line and end "f gauges c A M - 112 slip gu.rg. set consists of the following Range ln mm Steps in mm Number of Pieces 0.001 9 1.001 1.009- 49 0.010 1.010 1.490 - 49 0.50 0.50 24.50- 4 25 100 - 25 i 1.0005 Total 1 12 pieces - up the follorving dimensions rvith least Using the above set of siip gauges buiid (04 Marks) n.,.ni., of siip gauges if 29975 mm ii) 101005 mm d. Define the follJriirig : i; Tolerance ii) Fits iii) Limits (06 Marks) |o Lq. (04 Marks) b. rhat are limit gaugestHo* they are classified? t^-:--^r1:*;r *ftXtitrrur, . L- design of limit State minimrr.r, una *uximum material condition with respect to C. calculate the limits of tolerance and allowance for a shaft and hole pair designated by 30 d. Hz hs Given i) 30 mm lies in steps of 18mm and 30mm Standard tolerance I:045 (ry5) -i- 0001D" ii) iii)IT7 : 16r, and IT8 :25i (06 Marks) zones and allowance Use conect units. Also sketch the tolerance (05 Marks) a. What are Comparators? How they are classified? r ,-1 :.^ ^1^^-r,, method of the b. Describe *itf, u n.ui sketch a mechanical comparator and explain clearly -c (07Marks) magnificationadoptedinit i ., of working of a LVDT --..t-:^*^r^r/r-r (04 Marks) c. Briefly explain ,riit, u neat sketch the principle d.Explainhowarir.Uurmaybeemployedtodeterminetheangleofataperedbar104Marks) the same (06 Marks) a. What is meant by "Best Size Wire"? Derive an expression for b.Whatismeantbyeffectivediameterofascrewthread?Explainwithaneatsketchhowthe (08 Marks) same can be measured using three wire method ^ ^-,-- ^ -r a spur gear tooth using of c. Explain with a neat sketch ih. -.ur*ement of chordal thickness (06 Marks) a vemier caliPer. I of Z
  3. 3. =1 TP4ZB PART B . MEASUREMENTS 5a. Define measurement and measurement system with an example for each. (04 Marks) b. With the help of a block diagram, show the three stages of a generalized measurement systern. Atrso explain the function of each stage. (06 Marks) c. What is a tansducer? Explain with an example the meaning of primary and secondary transducer. (07 Marks) d. What are the disadvantages of a mechanical transducer? (03 Marks) a. How are intermediate modifuing devices classified? What are the inherent problems associated with mechanical modifuing devices. (05 Marks) b. What is meant by an input circuitry? Explain with a block diagram the concept of Telemetry. (07 Marks) a. Explain with aneat diagram a light beam oscillograph (construction and working). (08 Marks) 7a. What is a Thersrocouple? State and explain the lav;s of Thermocouple. (06 Marks) b. Define the following : i) Static pressure ii) Dynamic pressure iii) Absolute pressure iv) Gauge pressure v) Vacuum vi) Atmospheric pressure. Also sketch the relation amcrlg (iii), (iv), (v), and (vi). (08 Marks) c. Explain with a neat sketch, the working of a Mcleod gauge. (06 Marks) Write short notes on four of the following : a. Mounting of Strain gauges. b. Gauge factor. c. Wheat stone bridge. d. Autocollimator. e. HydraulicDynamometer. f. Analytical balance. (20 Marks) ****rr 2 ofZ
  4. 4. Page No...1 IP42B @ USN NEW SCHEME Fourth Semester B.E. Degree Examination, July 2007 AU/IP/tM/ME/MA Metrology and Measurements Time: 3 hrs.l [Max. Marks:100 lYote z Answer any FIYE full questions choosing at leust TWO fall questions from each Part. PART A L a. Discuss the advantages of using wave length standard as basic unit to define primary standard of length. (04 Marks) b. Explain with an illustration. how end standards can be derived from trine standards. (10 Marks) c. Three 100 mm end bars are measured using a Brookes level comparator by first wringing thein together and comparing with a 300 mm bar and then inter comparing them. The 300 mm bar has a known eror of + 42ptm and the three bars together measure 64prrn iess than the 300mm bar. Bar A is 18ptm longer than bar B and 23 ytm longer than bar C. Find the actual length of the bar. (06 Marks) a. of limit gauges. State and explain Taylors principle for the design (04 Marks) b. A fit is designated by 60 H8/C8. 60mm basic size lies in the diameter range 50mm to 80mm. Upper deviation of the shaft C = -(95 + 0.8D) pm, IT8 : 25i, where i:0.45i/5-+0.001D. Sketch the and showthese uponthe actual dimensions of fit hole and shaft. (Io Marks) c. With an example each, briefly explain the three tlpes of fit. (06 Marks) 3 a. What is a comparator? How does it differ from a rneasuring device? (06 Marks) b. Sketch and explain any two devices (using eiastic members) for amplifting linear movement in mechanical comparators that do not require bearings. (06 Marks) c. With a neat diagram, explain the principle of working of tr VDT. (08 Marks) a. With the help of a neat sketch, explain the use of a sine center. (08 Marks) b. Define effective diameter of a screw thread. Explain how the 2-wire method could be used for measuring the effective diameter of a screw. (08 Marks) c. Write a note on interferometry. (04 Marks) PART B 5 a. Define the following : i) accuracy, ii) precision, iii) sensitivity, and iv) speed of response. Give examples for each. (08 Marks) b. Define error in measurement. Give a classification of errors. (04 Marks) c. With the help of a block diagram, explain the three stages of a generalized rneastlrefllent system. (08 Marks) Contd...2
  5. 5. Page No...2 IP42B What is a transducer? List the advantages of electrical transducers over mechanical transducers , (08 Marks) b. Explain with a neat sketch, the construction and working of a cathode ray oscilloscope. (oE Marks) c. Write a note on X-Y plotters. (04 Marks) a. With a neat sketch, explain how strain in a machine element subjected to tensile load can be measured using electrical resistance strain gauges. Use a compensation gauge also. (10 Marks) b. What is a thermo couple? With a schematic diagram, explain how a thermo couple can be used to measure the metal cutting temperature on a lathe. (10 Marks) Write short notes on the following : a. Optical pyrometer. b. Pronybrake. c. Bridgeman gauge. d. Preparation and mounting of strain gauges. (20 Marks) ,r*rtrr*
  6. 6. Page No... 1 IP42B NEW SCHEME USN Fourth semester B.E. Degree Examination, july/August 2004 Common to ME/IP/IM/MA/AU Metrology and MeasurementsTime: 3 hrs.I lMax.Marks : 1OO Note: L. Ansuter FIVE full questions choosing at least two questions from each part. 2. Drazn neat sketches zuith pencil wheneoer required. PART - A 1. (a) Distinguish between line standard and end standards. Give examples of these two types of standard (5 Marks) (b) Discuss the need of har.,ing light wave as standard of measurement. (4 Marks) (c) Write a brief note on the manufacture of slip gauges. (5 Marks) (d) Build up a dimension of 78.3667 mm using M1,12 set slip gauges. (5 Marks) 2. (a) Explain brieflv the difference between the interchangeable manufacture and selective assembly. (4 Marks) (b) Determine the tolerances on the hole and the shaft for a precision running fit designated by 50H7 /96. You may use the following aid for solving the problem. i) 50 mm lies betiveen 30-50mm ii) i : 0.46(D)1/, + O.0A7D(rni,uon,s) iii) Fundamental deviation for 4 hole = 0 iv) Fundamental deviation for g shaft =-2.5 D0.s4 microns. v) ITT :16i, vi) ITG :7Ai. (10 Marks) (c) Give the detailed classification of plain gauges. (6 Marks) 3. (a) Mention a few basic requirements of a comparation for general workshop work. (4 Marks) (b) Describe any one of the available mechanical comparators. How will you distin- guish between mechanical and optical-mechanical comparators. (10 Marks) (c) Explain the working principle of solex pneumatic gauge with sketch. (5 Marks) 4. (u) Explain with neat diagram the working principle of N.P.L flatness interferometer. (8 Marks) (b) Describe the working of a vernier bevel protractor with a neat sketch. (6 Marks) (c) How effective diameter of screw thread is measured using 3-wire method. Give set up for the above one. (G Marks) Contd.... 2
  7. 7. IP42BPage PART - B {5 Mrrks} (al Explain the generalised measurement system. Give examPles 5. resPect to instrument (b) Explain the following with i) Sen-sitivitir ii) threshold iii) hysteresis iv) loading ef{ect (2x4=6 Marks) in measuiement& also state the factors of errors (c) Give the detailiciassification (7 Maiks) iesponsible for the above errors (4 Marks) examples 6. (a) Differentiate betrveen active and passive transducers "tith (4 Marks) over other transducers (b) State the advantages of electrical transducers (6 Marks) devir ces in instrumentation (c) State few intermediate modifying (6 Marks) (d) Write a note on telemetrY CRO & give its aPPlication N{arks) (8 (a) Expiain the working principle of give the working urinciple with sketch (6 Marks) (b) where Pirani gauge is used and which -working principie of hydraulic dynamometers t il:i] (c) Explain in detail the foi torque nreasurement (6 Marks) 8. (a) thernrocouPle opticai pyrometer (6 Marks) (b) T;lit: r,:XJ Explain the working principle or of Poissons factor of the strain gauges in terms (c) Derive the expression for the gauge (5 ]r{arks) ratio. (2 Marks) (d) State different tlpes of strain gauges ;t* * **
  8. 8. IIIrIr Page.S/o... I ME4OI USNY Fourth Semester B.E. Degree Examination, JanuarylF ebruary 2004 Mechanical Engineering MetroloEy and Instruneentation Time: 3 hrs.l lMax.Marks : lOO Note: 7. Answer a,ny FwE fall q.uestions. 2. All questions cclrry equal ma.rhs. 3. Shetches showld be drawm. whereaer neeessa,ry. 1. (a) Differentiate clearly between line and end stan<iards of measurement and give exampies in each. (b) Describe with a neat sketch, the constructional features of an "International Prototype Meter" and explain what are Bessels points? (c) A set of slip gauges with 87 pieces is available as given below : Range Step No. of pieces 1.0005 1 1.001-1.009 0.CIO1 I 1.01 - 1.49 0.01 49 0.5 - 9.5 0.5 19 10.0 - 90.0 10 CT Buiid the following dimensions by buiiding block procedure to choose exact number of slip gauges i) 29.758mm ii) 46.535mm. (4+8+8=20Marks) 2. (a) Define the following terms : i) Limits ii) Tolerances iii) Fit and iv) Deviation. (b) Name and explain briefly the different t;,pes of frt as per BIS and show them by neat schematic diagrams. (c) What are the systems of lirnits and fits? Explain briefly, which system is followed in India and why? (4+8+8=20 Marks) 3. (a) A fit is indicated as 20H78. Determine all tire dimensions for the fit and name the type of fit. Given that, the tolerance unit i:0.45 -l-0.001, " 1T (microns), upper derivation for shaft t5pe f : -5.5D041, tolerance IT7=16i, IT8=25i, 20mm diameter lie in the diarneter step of 18 and 30. Represent the dimensions graphically. (b) What are inspection gauges? Draw neat sketches with all features of i) Double ended plain plug gauge and ii) Double ended plain snap gauge. (12+8=20 Marks) 4. (a) What is a comparator? How does a comparator differ f?orrr ihu measuring instrument? ft,) Give a iist of various tlpes of cornparators. Contd.... 2
  9. 9. Page No... 2 ME404 (c) With the heip of a neat sketch, explain the construction and working principle of a Johansion Microkator. (5+3+12=20 Marks) 5. (a) Illustrate with neat sketches, all the nomenclature of external and internal paraliel screw threads. (b) Draw a neat sketch of a tool makers microscope and explain briefly the I construction and uses.Lr{ I (c) With a neat sketch show all the gear terminologies of a spur *?u*r=r, Marks)t 1 6. (a) What is measurement? What are the methods of, measurement? Mention the two conditions that a measuring standard should satisfy.I (b) With the help of a neat block diagram, explain trriefly atrl the three stages of aI generalised measuring system. (c) Define an error. How are errors classified? Give reasons for each type of error during measurement. (6+8+6=20 Marks) 7. (a) Define a transducer. Mention an;4 five mechanical and five electrical trans-(i,1 ducers.E (b) What are the advantages of electrical transducer elements over mechanieal transducer elements? I (c) With a neat sketch, explain the construction and working of an ionisation transducer. (U+E+10=20 Marks) OR (a) What is a dynomometer? List all the types of dynamometers. (b) With a neat sketch, explain the working of a rope brake hydraulic dynomometer. (c) What do you mean by low pressure measurement? Explain with a neat sketch the measurement of low pressure by Mc. load gauge. 4+6+10=2o Marks) ( 8. (a) What is a thermocouple? State the laws of thermocouple. (b) tist various thermocouple materials used. (c) What is a strain gauge? Give a list of gauge configuration, grid material and backing materials used. (6+4+10=20 Marks)
  10. 10. (-) at-- TPage No... 1 ME4OY USNFourth Semester B.E. Degree Examination, July/August 20OB Mechanical Engineering Metrology and InstrumentationTime: 3 hrs.I [MaxMarks : IOO Note: L. Ansuter any FwE full questions. 2. Att questions carry equal marh* B. Neat shetches should be drawn whereoer necessary. 1. (a) With suitable examples explain line standard and end standard measurements. (4 Marks) (b) What are airy points? How do they differ from the points of minimum defection. (6 Marks) (c) Differentiate between i) Tolerance and allowance ii) HoIe basis system and shaft basis system. (6 Marks) (d) Explain Taylors principle for the design of limit gauges. (4 Marks) 2. b) Illustrate with examples i) Geometrical tolerance ii) Dimensionaltolerance iii) Positional tolerance. (6 Marks) ft) A shaft-hoie pair is designated as H7d8. The standard toierance is given by ,- i :0.45 i/D + 0.001r, where D = Diameter (mm) falling in the step 18-30mm. The fundamental deviation for frt d is given by -tODoaa. Take wear allowance as llVo of the gauge tolerance. Determine the shaft and hole dimensions, their toierances clearance, interfer- ence and the class of fit. Sketch the fit and mark the dimensions clearly. (14 Marks) 3. (a) What is the difference between a comparator and a measuring instrument? (4 Marks) (b) Sketch and label the parts ofa vernier bevel protractor. (6 Marks) (c) Distinguish between i) Sine bar and sine centre ii) Angle gauges and slip gauges. (6 Marks) (d) Select the sizes ofangle gauges required to build the following angles i) 37o2g24tr ii! 1g2ogt 42t . (4 Marks) Contd.... 2
  11. 11. Page I{o... 2 ME404 4. (a) What are the various types of pitch errors on threads and explain the reasons for the same. (6 Marks) (b) How do you find effective diameter of a srrew thread using trn o-wire method? (6 Marks) (c) How do you measure the following in case of a spur gear i) Runout ii) Tooth thickness iii) Back lash. (8 Marks) 5. (a) Distinguish between : i) Active and Passive Transducers ii) Digital and Analog measurement iii) Direct reading and nulI baiancing. (6 Marks) (b) Explain with an exarnple the various stages of a generalised measurement system. (8 Marks) (c) Expiain with sketches : i) Hysteresis ii) Threshold iii) Repeatability iv) Sensitivity clrift. (6 Marks) 6. (a) Explain with neat sketches the following i) Prezo electric transducer ii) Ionisationtransducer (10 Marks) (b) Explain with a neat sketch, the method of torque measurement of rotating shafts using strain gauges. (10 Marks) 7. (a) Discuss briefly with sketches two types of elastic pressure transducers. (4 Marks) (b) With neat sketches, explain the working principle of i) Mcleod gauge ii) Knuolsm gauge. (10 Marks) (c) With a neat sketch expiain bi-metal strip thermorneter. (6 Marks) 8. (a) With a neat sketch, explain resistance thermometer. (4 Marks) ft) How do you calibrate the given strain gauge? (4 Marks) (c) Enumerate the necessary precautions to be taken while mounting a strain gauge on a test piece. (6 Marks) (d) What is temperature sensitivity? Explain how is it compensated. (6 Marks) *****
  12. 12. Pege No... 1 ME40 Reg. No.Fourth Semester B.m. Degree Exarnination, JanuarylFebruary 2003 Mechanical Engineering Metrolory and Instrumentation Time: 3 hrs.l lMax.Marks : 1OO Note: ,nswer a,ny FIVE futt questions. I". (a) What are protoctor gauges ? Explain. (4 Marks) (b) The slip gauge set M38 consists of the following : Range Steps Piece 1.005 1 1.01 - 1.09 0,01 I 1.1 1q 0.1" I 1.0 - 9.0 1.0 I 10.0 - 100.0 10.0 10 List the slip gauges to be wrung together to produce following dimensions: i) 29.975 ii) 101.345 (6 Marks) (c) Describe the steps in wringing of slip gauges. (4 Marks) (d) List and explain the different classes of fits as per BIS. (6 Marks) 2. (a) What are the allowances to be considered in the manufacturing of a gaugei (4 Marks) (b) Determine the actual dimensions to be provided for a shaft and hole of 90 mm size for Ilsee type clearance fit. size 90 mm falls in diameter steps of 80 and 100. Value of tolerance unit, i:0.45tW) * 0.001 DVdlue of.tolerances for i. 1T8 and IT9 grades are 25i and 40 Value of fundamental deviation for e type shaft it -11P0+1. Also design the GO and NO GO gauges as per the present British system in which the sarne workshop and in.spection gauges are used. (16 Marks) 3. (a) With neat sketches descrihe the construction and working of .a) Sigma comparameter b) Terminology irr gear tooth measurement and gear tooth vernier. (20 Marks) 4. (a) Describe the S-wire method of measuring effective diameter of threads. (5 Marks) (b) What is best wire size ? Derive an expression fer the same. (5 Marks) (c) With a schematic diagram explain the working of photo-electric auto collimater. Ust its applications. (10 Marks) Contd.... 2
  13. 13. Page No... 2 ME/X04 5. (a) Explain the terms : i) Precision ii) Hysterisis iii) RepeatabilitY iv) Iaading effect (8 Marks) (b) Describe the errors mentioned below and suggest methods to avoid them. i) Parallax error ii) Baek lash error (6 Marke) (c) Describe the three stages of measurement with a suitable example. (6 Marks) 6. (a) With a neat sketch explain the working of a LVDT. (5 Marks) (b) compare mechanical and electrical transducers. (6 Marke) (c) Explain the working of proving ring. (5 Merks) (d) What is the working principle of platform scale ? Explain. (5 Marke) 7. Describe the eonstruction, working and applications of the following (a) Mcleod gauge (1O Marks) (10 Marks) (b) Radiation $rrometer 8. Write notes on any FOUR. 14yg=20 Marks) (a) Interchangeability and selective assembly (b) Tool makeys microscoPe (c) Gear tooth micrometer (d) Gauge factor (e) Null balance method of strain measurement *{< * **
  14. 14. (Pages : 2) ME-404 FOIJRTH SEMESTER B.E. (MECHANICAL) DEGREE EXAMINATION[. METROLOGY AIYD INSTRI.]MENTATION Tirne : Three Hours Maximum : 100 Marks Answer any five full questions. Answers must be to the Point onlY. Suitable assumptions may be made for missing data stating the same clearly. 1. (a) State at ieast three important characteristics of line standard and end standard instruments. (3+3=6marks) (b) dnd hence build the following dimensions Give details of M-87 set : (i) 49.3825. (ii) 87.32t5. Q+2+2=6marks) (c) Discuss in brief "hole based and "shaft based" system of fits. Which is preferred. whv ? (6+1+1=Smarks) Z. (a) Calculate all the relevant dimensions of 35}Jrlf, frt dim 35 falls in the step of g0 - b0 mm. Fundamental deviation for "fshaft is s $.$ po { So= 0.45 tE + 000 D. IT = 16 s IT8 = 25 so (10 marks) (b) Design a suitable workshop standard plug gauge to check 35H2. Give complete specification of gauge. (10 marks) 3" (a) Give details of classification of comparators. (6 marks) (b) Sketch and explain in detail working of back pressure type pneumatic comparator. (10 marks) (c) Explain the working principle of auto collimator. (4 marks) 4. (a) Derive the expression for calculating chordal thickness and addendirm height of spur gear. (6 marks) (b) the expression for best site wire for 3 wire method. (6 marks) aDerive (c) State the different types of errors in the gears. (4 marks) (d) Sketch the block diagram of optical system of microscope. (4 marks) E. (a) Define and state the signifrcance of following terms in measurement : (i) Accuracy. (ii) Precision. (iii) SensitivitY. (iv) Repeatability. (4x2=Smarks) (b) Discuss with block diagram generalised measurement system with examples for each stage elements. (3 + 3 + 3 + 3 = L2 marks) Trrn over
  15. 15. "6. (a) Give the detail classification of mechanical transducers with their applications. (10 marks) (b) Expiain in detail the working principle of LVDT. Draw the relevant characteristic vs. gurye. (10 marks)7. (a) Explain the working principle of prooving ring. (4 marks) (b) With the help of neat sketch explain the working principle of prony brake dynamometer. (6 marks) (c) Explain the working and application of Mcleod gauge. (6 marks) (d) List the instruments used for high pressure measurement. (4 marks)8. (a) State and explain the laws of thermocouple. (6 marks) (b) Explain the working of resistance thermometer. (4 marks) (c) Write a brief note on total radiation p5rrometer. (10 marks)
  16. 16. Page --o.-" J ME404 @ Reg. No. Four:th Semester B.E. Degree Examination, July/August zooz Mechanical Engineering Metrology and fnstrumentationTime: 3 hrs.l [Max.Marks : l0O Note: 7. Answer crny FIVE fall questions. 2, Draw neat shetehes whereaer necessary. 3. All questions ca,rry equal marhs. 4. Answers must be brief a,nd to the point. 1. (a) Distinguish clearly between "Line Standards" and "End Standards". Give examples of the standards. (6 Marks) (b) Build up a dimension of 35.4875mm using M112 slip gauge set. Provide a pair of protector slips of 2.5mm thickness each at both ends in addition to the gauges given beiow : Size Increment No. of pieces L.005 NIL one 1.001 to 1".009 0.001 Nine I 1.010 to 1.490 0.01 Forty rune I 0.5 to 24.5 0.5 Fortv nine I 25 to 100 25 Four TOTAL 112 pieces (6 Marks) (c) Explain TAYLORs principle of limit gauging and explain the variations from TAYLORs principle. (E Marks) (d) List out any three disadvantages of material standards. (3 Marks) 2. (a) Determine the tolerances on the hole and the shaft for a precision running fit designated by SAH7ga; given i) 50mm lies between 30-50mm ii) i : a.45(D)tls + 0.0otDpr iii) for H hole, f.d=0 iv) F.D for g shaft * -2.5p0s+ State the actual maximum and minimum size of the hole and shaft and maximum and minimum clearances. $zMarks) (b) What is ointerchangeability"? List out the advantages of interchangeabiiity. (4 Marks) (c) Explain what you understand by "seiective Assembly". what are the characteristics of "Selective Assembly"? (4 Marks) Contd..,, 2
  17. 17. Page I{a... 2 n/tr8404 S. (a) Explain, with a neat sketch, the working of a "Solex Pneumatic Compar.ator". (10 Marks) (b) rith a neat sketch, explain how an optical level protractor works. (5 Marks) (c) Define precisely the following terms rnith respect to screw threads. i) Axis of the thread ii) Crest of the thread iii) Root of the thread iv) Pitch and v) Lead. tE Nrarks) 4. (a) Explain, t.ith a schematic diagram, the method of measuring the major diameter of a screw thread using bench micrometer. (6 Marks) (b) With a neat sketch, explain the construction of a tool makers microscope. What are its applications? (9 Marhs) (c) With the help of a neat sketch, explain the method of determining the chordai thickness of a gear tooth using vernier gear tooth caliper. (E Marks) 5" (a) Strhat is measurement? What are the requirements of an ideal measurement sYstem? (2+3 lvlarks) (b) What are the fundamental methods of measurement? Explain with examples. (l+2+2 Marks) (c) How are errors ciassified? Explain each type with examples. Indicate the remedial actions to be taken. (2+4+4warks) (a) Dr:fineTransfer Efficiencv (1 Marks) (b) List the advantages of electricai transducers over mechanical transducers. (3 Marks) (c) List out six mechanical transducing elements and mention the transducing action they perfbrm. (6 Marks) (cl) With a neat sketch, explain the working of LVDT. (10 Marks) "7 (a) trxplain the working of a prony brake dynamometers, rvith the help of a neat sketch" (8 Marks) (b) Explain horv a tsridgernan gauge is used to measure ilressures. Whai, are its linritations? ---i* Marksi (c) Expiain the working of a device used to measure high temperatures. (4 Marks) (a) Wtrat are the steps to be taken in the preparation of the specimen and mountirig of strain gauges. (6 Marks) (b) Discuss the problems associated with strain gauge instaliaiions. (6 Marks) (c) Draw a neat diagram of a simple resistance bridge arrangement for strain measurenrent. (4 Marks) (d) Differentiate between Null l:alance and deflection method of operation of bridge circuit" (4 Marks) ** * :h*
  18. 18. PrW: No... I ME404 0 Reg. No. Fonrth semester B.E. Degree Examination, February 2oa? Meehanical Engineering Metrology and InstrumentationTime: 3 hrs.] : IOO [Max.Marks Note: Ansuer any FIVE full questions. Ansuers must be to the point only. Suitable assumptions may be mide for missing data stating the same clearly. 1. (a) What do you understand by line and end standards? Discuss their relative characteristics. (6 Marks) (b) Enumerate the advantages of using wavelengtJr standard as a basic unit to define primary standards (B Marks) (c) E:<plain the NPL method of deriving end standards from line standards. (8 Marks) (d) What are Airy points? (3 Marks) 2. (a) E>plain what is meant by i) Interchangeable part. ii) Universal interchangeability. iii) Iocal interchangeability. (6 Marks) (b) What is the difference between unilateral and bilateral tolerances? why unilateral tolerance is preferred over bilateral tolerance? (6 Marks) (c) Determine the type of fit, after decidlng the fundamental deviations and tolerances in the following. (9 Marks) Fit $70Hs.e7, Diameter step (SO - gO) Fundamental deviation for e shaft = - 11 pl,a IT7 : t6d ITs :49; i:0.45 l/D +0.001D 3 (a) Calculate the dimensions of pl_ygand ring gauges to control the production of 5o mm shaft and hole pair of Hida. te rii-towilng assumptions may be made. 5O mm falls in the diameter step of 30 - 5O mm. "upp.r airriatiooldr .,d,, shaft i" -16p0.44. IT7 : !9,i, ITs - )gi, i :0.45}D +0.001D. (1O Marks) (b) What are the required characteristics of comparators? (4 Marks) (c) Explain with a neat sketch the principle of working of Johansson Mikrokator. (6 Marks) 4. (a) Dqplain why it is preferred not to use a sine bar for generating angles larger than 450 if high accuracy is desired. (5 Marks) (b) Select the sizes of angle gauges required to build the following angle. Show the arrangement of gauges. i) 57og4rgtr ii) 12o21t36r (5 Marks) Contd..". 2
  19. 19. 2 ME4O4, (c) What are the two corrections applied in the measurernent of effectiie diameter by the method of wires? (5 Mcrks) (d) Descrlbe a gear tooth-vernier caliper and show how thLis is used for checking gears. ($ Marks)5. (a) What do you mean by static calibration? Sketch the calibration curve ,ri"?tlt instrument and oqplaln how it is obtained (6 Marks) (b) E>rplain the following: i) Zero drift and sensitivity drift. ii) Threshold, Resolution and Hysteresis (8 Marks) (c) What are the sources of errors in instruments? Explain {6 Mar.ks}6. (a) Define the word Transducer lNhat elo you understand by active and pa"ssi;: transducers? Give examples. (S Ivtarks) (b) Explain the following with neat skr:tches. i) Mutual inductance transducer., ii) Piezo electric transducer. {10 Marksi (q) E4plain any one type of elastic tfansducer with a neat sketch. (Fr Mark*7. (a) E4plain the working and application of a Bridgeman gauge. i6 *Iarks} (b) Explain with a neat sketch the analylical balance {5 Maris) (c) with the heip of a neat sketch explain the working of a plony brake Jynairlo- meter. (6 Marksl (d) Write a note on h5ldraulic dynamometers. {3 Marhs)8. (a) E>qplain with respect to strain gauges i) Cross sensitivitY. ii) Temperature compensation iii) strain. Positioning of gauges to measure torsional (e trla:rhsi (b) Write a note on bonding materials of strain gauges (5 Mar:hs! (c) Write a note on thermocouple materials and some forms of therrnoco;lple (6 Markst construction. *****
  20. 20. EL.-.--- ,,, -Try NO,,. 1 n4E 404 0 Reg. No" Fourth Semester B.E. Degree Examination, August ZOOI Meehanical Engineering Metrology and Instrumer*tation Time: B hrs.l Note: j. lMax.Marks : 100 .1ry FInE full questions. answe, 2. All questions caruy ,q;{;;;kr:. J. rflear sketches tnoLla=i" iiu*"*hrr"u* I necessary. --:lr 1. (a) Describe with neat sketches : (i) imperial stanclard yard J (ii) International prototype (b) Describ. t.L. procedure metre (ro Marks) M-87. build rip trr. rrri"ving dimensions ^ ;;;":;::^"^^,. gauge set for wringing of slio gauges using a shp i) 29.758mm and (ii) 46.635mm z. (a) Illustrate the principle of Go_No,Go gauge" ,ro Merks) trr)oe".U*HE,#r%;?"?ffi f"r]filr€i*T.i"checkeomponen."n";:#;: 25 mm falls in the diameter step of 18 and 30 upper deviation shaft = and i(microns) = O.4S for,f the rr"""""i#c?jcutation {/D + 0.001r, where D is in mm, show all,q..5Dr.r, 3 () (lS Marks) ( "#;fS,".Hf.,.3, Jffi#ff.t"n the construction and working or I [b) Describe the procedure to verifu thc *a^^* i, (ro traarks) ^- - sin e c e ntr. uLo ;i,p;ffi .":ifl"lm jT,iif,itdI 4 n i 3,1,111ffi pl u g ga u ge *:n5 #"#,:i%["]J{ a screw thread measured and what are the different types (b) Iilustrate the use of gearI tooth vernier calriper to measur:e tooth ,"[lH::] 5 (a) ,what do you understand bv the fnllnrr"i-^ +^___ tro ni"r-i") (i) ii;p e;;urutv lil "i;;"y{,,1}. "#tfl frf Ti,if;., (iv) Hys tb) Expiain with an example the three ",, stages of a generalized t e ri si s measurement 6 n (1O Marks) #;fl1ffi#:i"i"ffi?: sketch the construction and working of a erectronic [b) what is a pneumatic load ceit? (lo Marks) Explain 7. (a) Describe with a neat sketch {t0 Marks) Mclpnrt ro^,rr,* r -;m*,n"*principre"r,n.X""T;XI:HTfil?;;tethe.ppri"utl[-; 8 (a) Describe the process of preparation a,d mounting (1O Marks) of strain guages. (b) Exptain (i) Calibration of strain gauges (ii) Temperature ** t ** ""*O.r,Jl,H_, (lo Marks)