MCQ - Unit 1 Metrology PDF

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P. Srinivasa Rao...

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Tolerances 1. What are the functional dimensions? a) Have to be machined and fit with other mating components b) Which have no effect on the performance of quality c) Need not to be machined to an accuracy of the high degree d) Function is more important than accuracy 2. Why tolerances are given to the parts? a) Because it’s impossible to make perfect settings b) To reduce weight of the component c) To reduce cost of the assembly d) To reduce amount of material used 3. What is bilateral tolerance? a) Total tolerance is in 1 direction only b) Total tolerance is in both the directions c) May or may not be in one direction d) Tolerance provided all over the component body 4. Which type of tolerance provided in drilling mostly? a) Bilateral b) Unilateral c) Trilateral d) Compound 5. What is mean clearance? a) Maximum size of hole minus maximum size of shaft b) Minimum size of hole minus minimum size of shaft c) Mean size of hole minus mean size of shaft d) Average of both size of shaft and hole 6. Which of the following is incorrect about tolerances? a) Too loose tolerance results in less cost b) Tolerance is a compromise between accuracy and ability c) Too tight tolerance may result in excessive cost d) Fit between mating components is decided by functional requirements 7. Quality control charts doesn’t depend on which factor? a) Normal distribution b) Random sampling c) Independence between samples d) Binomial distribution 8. Which of the following option is true for given statements? Statement 1: Bilateral tolerances are used in mass production techniques. Statement 2: The basic size should be equal to upper and lower limits. a) T, T b) F, F c) T, F d) F, T

9. If a clearance fit is present between shaft and hole, what is the tolerance on shaft or hole for a complete interchangeable approach? a) ½ of maximum clearance – ½ of minimum clearance b) ¼ of maximum clearance – ¼ of minimum clearance c) Maximum clearance – minimum clearance d) ¾ of maximum clearance – ¾ of minimum clearance

Interchangeability 1. Which of the following option is incorrect about interchangeability? a) Increase output b) Increase cost of production c) Useful in mass production d) Assembly time increases 2. What are the main considerations for deciding the limits of a particular part? a) Functional requirement b) Economics and interchangeability c) Interchangeability and functional requirement d) Interchangeability, functional requirement and economics 3. For full interchangeability, what is the relation between the process capability of a machine and manufacturing tolerance of the part? a) Process capability = Manufacturing tolerance b) Process capability ≥ Manufacturing tolerance c) Process capability > Manufacturing tolerance d) Process capability ≤ Manufacturing tolerance 4. Which of the following option is correct in given statements about interchangeability? Statement 1: Standardisation is not so much of importance for interchangeability. Statement 2: Interchangeability follows ‘normal distribution’. a) F, T b) T, T c) F, F d) T, F 5. Which of the following option is not correct for ‘full interchangeability’? a) This type of interchangeability is not feasible sometimes b) Requires machine which can maintain low process capability c) Machines with very high accuracy are necessary d) For interchangeable production, this type of interchangeability is not must 6. What is the main use of automatic gauge in selective assembly? a) Check accuracy of parts b) Check parallelism of parts c) Divide group of parts with some tolerance in smaller groups d) Use to check errors in parts 7. What is the correct formula to find no. of groups in selective assembly? a) Process capability / Tolerance desired b) Tolerance desired / Process capability

c) Tolerance desired * Process capability d) Tolerance desired + Process capability 8. What is a limit system? a) Series of tolerances b) Series of fits c) Series of clearances d) Series of limits 9. Which of the following is correct for selective assembly? a) Not suitable for industrial purposes b) Cost increases due to automatic gauging c) Wastage is high due to selective selection d) This method is followed in ball and roller bearing units ---------------------------------------------------------------------------------------------------------------------------------------------------

Terminology 1. What does ‘50’ represents in 50H8/g7? a) Basic size b) Actual size c) Maximum limit of size d) Minimum limit of size 2. Which of the following is incorrect regarding terminology? a) Grades of tolerances decides manufacture’s accuracy b) For any basic size there are 20 different shafts c) Line of zero deviation is known as zero line d) Tolerance has no sign 3. What is the actual deviation? a) Algebraic sum between actual size and corresponding basic size b) Algebraic difference between actual and corresponding basic size c) Average of actual and basic size d) Algebraic difference between upper and lower deviation 4. What is the condition for a positive upper deviation? a) Maximum limit of size > basic size b) Maximum limit of size is < basic size c) Minimum limit of size > basic size d) Maximum limi t of size < basic size 5. How many holes are there for any basic size? a) 22 b) 24 c) 26 d) 28 6. What does ES represent in terminology as per IS: 919? a) Lower deviation of hole b) Upper deviation of shaft c) Lower deviation of shaft d) Upper deviation of hole

7. What is ‘IT01’? a) Basic size of hole b) Basic size of shaft c) Tolerance grade d) Standard tolerance factor 8. For tolerance grades 5 to 16, what is the formula for standard tolerance factor? (D=mean diameter in mm) a) 0.45 (D)1/3 + 0.001D b) 10*D c) 0.45 (D)3 + 0.001 D d) 20*D 9. What is the hole size which is covered by IT05? a) 500 mm b) 600 mm c) 700 mm d) 800 mm

Guide for Selection of Fits 1. Which of the following is not true for hole and shaft basis systems? a) Hole basis system is generally preferred over shaft basis system b) Shaft basis system can be used when products are made from bright drawn bars c) Choice of the system depends upon nature of the product d) In hole basis system, allowances are applied to the hole 2. Which of the following grade of a hole is mostly used for non-circular fits? a) H5 b) H6 c) H7 d) H9 3. Which of the following option is incorrect for clearance fits? a) Shaft ‘a’ gives a large clearance b) Shaft ‘n’ is used for clearance fits c) Shaft ‘d’ can be used for loose pulleys d) Shaft ‘g’ is expensive to manufacture 4. What is the range of shafts which produce transition fits? a) Shaft ‘a’ to ‘h’ b) Shaft ‘e’ to ‘n’ c) Shaft ‘d’ to ‘h’ d) Shaft ‘j’ to ‘n’ 5. Which grades are available in shaft ’j’ assembly? a) 1 to 5 b) 2 to 6 c) 3 to 7 d) 5 to 11

6. Which of the following grade is never used for fits? a) H10 b) H11 c) H8 d) H9 7. Which of the option is correct about the preference of shaft and holes in machine tool industries? a) ‘A11’ is of first preference in shafts b) ‘B9’ is of first preference in holes c) ‘c2’ is of first preference in shafts d) ‘b11’ is of second preference in holes 8. Which of the following option is correct for given statements regarding the selection of fits? Statement 1: Shaft ‘h’ is an interference fit and used only for running parts. Statement 2: Shaft ‘k’ is the true transition fit. a) T, F b) F, F c) T, T d) F, T 9. Which shaft is used in valve shaftings? a) Shaft ‘s’ b) Shaft ‘f’ c) Shaft ‘b’ d) Shaft ‘t’ 10. Which of the following gives interference fit? a) Shaft ‘n’ b) Shaft ‘p’ c) Shaft ‘m’ d) Shaft ‘g’ ---------------------------------------------------------------------------------------------------------------------------------------------------

Metrology-1 1. Maximum deviation in size of shaft or hole is known as a) Tolerance b) Fundamental deviation c) Clearance d) Interference 2. Nearest deviation between hole and shaft from the basic value is known as a) Tolerance b) Fundamental deviation c) Clearance d) Interference 3. When size of the smallest hole is more than size of biggest shaft then it is a) Clearance fit b) Interference fit c) Transition fit d) None of the mentioned

4. Value of minimum clearance is given by a) Size of smallest hole – size of biggest shaft b) Size of smallest hole + size of biggest hole c) Size of smallest shaft – size of biggest shaft d) None of the mentioned 5. Value of maximum clearance is given by a) Size of smallest hole – size of biggest hole b) Size of smallest shaft + size of biggest hole c) Size of smallest shaft – size of biggest shaft d) None of the mentioned 6. When size of smallest shaft is more than size of biggest hole then it is a) Clearance fit b) Interference fit c) Transition fit d) None of the mentioned 7. Value of maximum Interference is given by a) Size of smallest hole – size of biggest shaft b) Largest of shaft size hole – smallest hole size c) Size of smallest shaft – size of biggest shaft d) None of the mentioned 8. Value of minimum interference is given by a) Size of smallest hole – size of biggest hole b) Size of smallest shaft + size of biggest hole c) Size of smallest shaft – size of biggest hole d) None of the mentioned 9. For manufacturing of a certain amount of hole, maximum hole size was found to be 50.14 mm and minimum hole size was found to be 49.98. Tolerance in mm will be a) 0.12 b) 0.13 c) 0.16 d) 0.20 10. In manufacturing of hole and shaft, maximum shaft diameter was 49.88 mm and minimum hole diameter was found to be 49.94 mm. It is a a) Clearance fit b) Interference fit c) Transition fit d) None of the mentioned -------------------------------------------------------------------------------------------------------------------------------------------------

Metrology-2 1. In an assembly of hole and shaft, smallest hole was having diameter of 49.98 mm and largest shaft was having diameter of 49.94 mm. Minimum clearance in mm will be a) .08 b) .03

c) .001 d) .04 2. In an assembly of hole and shaft, smallest shaft was having diameter of 49.98 mm and largest hole was having diameter of 50.14 mm. Maximum clearance in mm will be a) 0.23 b) 0.26 c) 0.32 d) 0.12 3. In an assembly of hole and shaft, largest shaft was having diameter of 50.18 mm and smallest hole was having diameter of 49.98 mm. Maximum interference in mm will be a) 0.2 b) 0.3 c) 0.3 d) 0.1 4. In an assembly of hole and shaft, minimum shaft diameter is 49.36 mm and maximum shaft diameter is 48.20 mm. It is an example of a) Clearance fit b) Interference fit c) Transition fit d) None of the mentioned 5. In an assembly of hole and shaft, smallest shaft was having diameter of 50.16 mm and largest hole was having diameter of 50.14 mm. Minimum interference in mm will be a) 0.2 b) 0.3 c) 0.3 d) 0.1 6. Maximum material limit of shaft is a) Maximum diameter of hole b) Maximum diameter of shaft c) Smallest diameter of hole d) Minimum diameter of shaft 7. Maximum material limit of hole is a) Maximum diameter of hole b) Maximum diameter of shaft c) Smallest diameter of hole d) Minimum diameter of shaft 8. Minimum material limit of shaft is a) Maximum diameter of hole b) Maximum diameter of shaft c) Smallest diameter of hole d) Minimum diameter of shaft 9. Minimum material limit of hole is a) Maximum diameter of hole b) Maximum diameter of shaft

c) Smallest diameter of hole d) Minimum diameter of shaft 10. Allowance of hole and shaft assembly is equal to a) Sum of maximum metal limit b) Product of Maximum limit c) Difference of maximum metal limit d) None of the mentioned -------------------------------------------------------------------------------------------------------------------------------------------------

GATE MCQ’s 1) Newall system is a type of a. maximum hole size b. minimum hole size c. upper deviation which is zero d. none of the above 2) Which type of tolerance does a slip gauge have? a. Unilateral tolerance b. Bilateral tolerance c. Both a. and b. d. None of the above 3) Which type of deviation is observed while calculating hole dimensions? a. Positive b. Negative c. Zero d. All of the above 4) Which ISO standard is used in international automobile companies to set automotive quality system standards ? a. ISO 14000 b. TS 16949 c. ISO 9000 d. none of the above 5) ISO 14000 quality standard is related with a. Environmental management systems b. Automotive quality standards c. Eliminating poor quality d. Customer satisfaction 6) How is interference between shaft and hole calculated? a. Interference = maximum shaft – minimum hole b. Interference = minimum shaft – maximum hole c. Interference = minimum shaft + maximum hole d. None of the above 7) Which of the following is true for interference fit? a. Shaft is always smaller than the hole b. Shaft is always bigger than the hole c. Interference fits have shaft and hole of same dimension d. None of the above

8) Which among the following is a type of clearance fit? a. Force fit b. Push fit c. Slide fit d. Tight fit 9) What is a loose running fit? a. Loose running fit has minimum clearance b. They can be used in textile machinery c. Used in high precision task d. All the above 10) Which of the following statements is/are false? a. Interference is observed in tight fit b. Allowance represents minimum interference for interference fits c. Clearance is observed in push fit d. All of the above 11) What does allowance represent in clearance fits? a. It represents minimum clearance and is positive b. It represents maximum clearance and is positive c. It represents minimum clearance and is negative d. It represents maximum clearance and is negative 12) The study of scientific metrology deals with a. accuracy and methods of measurement b. standard specifications c. theories related to nature d. all of the above 13. In a bilateral system of tolerance, the tolerance is allowed on A.

one side of the actual size

B.

one side of the nominal size

C.

both sides of the actual size

D.

both sides of the nominal size

14. The algebraic difference between the minimum limit and the basic size is called A.

actual deviation

B.

upper deviation

C.

lower deviation

D.

fundamental deviation

15. Allowance in limits and fits refers to (a) maximum clearance between shaft and hole (b) minimum clearance between shaft and hole (c) difference between maximum and minimum size of hole (d) difference between maximum and minimum size of shaft

[GATE 2001]

16. Two shafts A and B have their diameters specified as 100 + 0.1 mm and 0.1 + 0.0001 mm respectively. Which of the following statements is/are true ? [GATE 1992]

(a) Tolerance in the dimension is greater in shaft A (b) The relative error in the dimension is greater in shaft A (c) Tolerance in the dimension is greater in shaft B (d) The relative error in the dimension is same for shaft A and shaft B +0.05 +0.20 17. A shaft diameter ( 20−0.15 mm) and a hole ( diameter 20+0.1 mm) when assembled would yield

[GATE 1993] (a) transition fit

(b) interference fit

(c) clearance fit

(d) none of these

18. The fit on a hole-shaft system is specified as H7-s6. The type of fit is [GATE 1995] a) clearance fit

b) running fit (sliding fit)

c) push fit (transition fit)

d) force fit (interference fit)

19. In the specification of dimensions of fits, [GATE 1998] a) allowance is equal to bilateral tolerance b) allowance is equal to unilateral tolerance c) allowance is independent of tolerance d) allowance is equal to the difference between maximum and minimum dimension specified by the

tolerance. 20. A hole is specified as 40 +0.05. The mating shaft has a clearance fit with minimum clearance of 0.01 mm. The tolerance on the shaft is 0.04 mm. The maximum clearance in mm between the hole and the shaft is [GATE 2007] a) 0.04

b) 0.05

c) 0.10

d) 0.11

21. For the given assembly: 25 H7/g8, match Group A with Group B

[GATE 2014]

Group A Group B P. H (I) Shaft Type Q. IT8 (II) Hole Type R. IT7 (III) Hole Tolerance Grade S. g (IV) Shaft Tolerance Grade (A) P-I, Q-III, R-IV, S-II (B) P-I, Q-IV, R-III, S-II (C) P-II, Q-III, R-IV, S-I (D) P-II, Q-IV, R-III, S-I +0.040 +0.005 22. Holes of diameter 25.0+0.020 mm are assembled interchangeably with the pins of diameter 25.0−0.008 mm. The minimum clearance in the assembly is [GATE 2015]

(A) 0.048 mm (B) 0.015 mm (C) 0.005 mm (D) 0.008 mm...