COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

1. Design factors based on yield strength are typically around 1.5 for
smooth, steady loads and range between 2.0 to 2.5 for minor shock. What is
the upper limit of the design factor recommended for conditions involving
severe shock loading, particularly when load reversal occurs during
operation?

A. 3.25 C. 3.5
B. 4.5 D. 4.0

2. Which type of tolerance is typically used for dimensions involved in

engineered fits, such as a pin fitting into a hole, where variation is
allowed in only one direction to control clearance or interference?

A. Bilateral C. Unilateral
B. Lateral D. Symmetrical

3. A single threaded trapezoidal metric thread has a pitch of 4mm, and a mean
diameter of 18mm. It is used as a translation screw in conjunction with a
collar having an outside diameter of 37mm and an inside diameter of 27mm. Find
the required torque in N-m to raise a load of 400kg if the coefficient of
friction is 0.4 for both thread and collar.

A. 32.6 C. 43.2
B. 35.8 D. 41.4

4. Within which temperature range does the oil film typically operate to
ensure proper lubrication without significant risk of thermal degradation?

A. 140° to 150° F C. 130° to 160°

B. 120° to 190° F D. 140° to 160° F

5. Above which approximate pitch line velocity should straight and Zerol
bevel gears be avoided due to performance concerns such as noise and wear,
making spiral bevel gears a more suitable choice?

A. 800 rpm C. 875 rpm

B. 850 rpm D. 900 rpm

6. A double thread Acme screw driven by a motor at 400 rpm raises the attached
load of 900 kg at a speed of 10 meters per minute. The screw has a pitch
diameter of 36 mm. the coefficient of friction on threads is 0.15. The friction
torque on the thrust bearing of the motor is taken as 20% of the total torque
input. Determine the motor power required to operate the screw.

A. 4.24 HP C. 3.24 HP

B. 5.33 HP D. 6.55 HP

7. What phenomenon occurs when the frequency of an external excitation matches

the natural frequency of a system, potentially leading to large amplitude
vibrations?

A. Unity C. Resonance
B. Obliquity D. Sinusoidal

8. D What is the term for a plane that touches contacting surfaces at a point
or along a line, without intersecting them?

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COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

A. Tangent plane C. Normal plane

B. Control plane D. None of these

9. What is the working strength in lbs of a 2’’ bolt which is screwed up

tightly in a packed joint when the allowable working stress is 1259.54 kg/cm2?

A. 20,500 lbs C. 20,400 lbs

B. 30,500 lbs D. 30,400 lbs

10. What term describes the slow chemical reaction of a metal with
environmental substances, resulting in its conversion to oxides or other
compounds?
A. Corrosion C. Cheaping
B. Rusting D. Weathering
11. Compute how many 3/8 inch diameter set screws required to transmit 3Hp at
a shaft speed of 1000rpm. The shaft diameter is 1 inch.

A. 1 C. 3

B. 2 D. 4

12. The follower reciprocates or oscillates in a plane parallel to the axis

of rotation of the cam:

A. radial cam C. cylindrical cam

B. cam curve D. tangential curve

13. Which of the following is part of a lathe machine:

A. fan C. cylinder
B. headstock D. Ropes
14. Kinematic pairs are those pairs that have:

A. Point or line contact between the two elements when in motion

B. Surface contact between the two elements when in motion
C. Elements of pairs not held together mechanically
D. Two elements that allow relative motion

15. It increases the fatigue strength

A. medium working C. quenching

B. cold working D. none of these

16. A single american thread power screw is to raise a load of 70kN. The screw
has a major diameter of 36 mm and a pitch of 6 mm. The coefficient of thread
friction and collar friction are 0.13 and 0.10 respectively. If the collar
mean diameter is 90 mm and the screw turns at 60 rpm, find the power input to
the screw in kW.

A. 4.1 C. 3.36

B. 3.5 D. 2.45

17. Which one is different from the remaining:

A. Cyaniding C. Nitriding
B. Flame hardening D. Electroplating

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COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

18. Couple is called:

A. Same directional force equal in magnitude and perpendicular

B. Opposite directional force equal in magnitude and perpendicular

C. Same directional force equal in magnitude and parallel

D. Opposite directional force equal in magnitude and parallel

19. When a metal is cold worked all of the following generally occur:

A. Re-crystallization temperature decreases

B. Ductility increases

C. Grains not become equi-axed

D. Tensile strength increases
20. The cylinder head of a steam engine with 250 mm bore is fastened by eight
stud bolts made of 30C8 steel. Maximum pressure inside the cylinder is 1 MPa.
What is the best specification of bolt to be used. Assume � �𝑦=300 MPa for
bolt material.

A. M16 C. M12

B. M14 D. M10

21. Unit of Power

A. N-m C. N-m/s
B. kg-m/s D. N/m^2

22. A 100 Kpa is equivalent to

A. 1 MN/m^2 C. 710 torr
B. 12.7 psi D. 103.2 kg/cm^2
23. Individual rigidity values

A. have no significance.
B. indicate how much stronger one member is than another

C. are significant only for ductile materials.

D. are significant only for brittle materials.

24. A steam engine cylinder has an effective diameter of 37.05 cm and the
maximum steam pressure acting on the cylinder cover is 181.35 psi. Calculate
the number of bolts required to fix the cylinder cover, assuming the diameter
is 2cm and permissible stress in the studs is 336.432 cmH2O.

A. 12 bolts C. 13 bolts

B. 10 bolts D. 9 bolts

25. The manhole cover of an ammonia storage tank is to be held by 36 stud

bolts. If the pressure inside the storage tank will remain constant at 12.5
kg per sq. cm and the manhole diameter is 508 mm. What would be the stress
area in sq. in if the load will be proportionally carried by the bolts?
Disregard elastic limit of material.

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COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

A. 0.22 C. 0.92

B. 0.43 D. 0.58

26. Cutting form the base of a work piece is:

A. New Cutting C. Undercutting

B. Overcutting D. Exact Cutting

27. There are 8 cutters in the series for each diametral pitch to cover the
full range from ______ pinion to a crown gear.

A. 18-tooth C. 16-tooth
B. 14-tooth D. 12-tooth

28. For heavy loads in aircraft bearings the materials used with lead to
reduce the risk of seizure is:

A. tin C. silver

B. zinc D. iron

29. Factor of safety for machine columns is 2 to _____ for steady loads.

A. square root of 25/4 C. square root of 9/4

B. square root of 49/4 D. square root of 81/4

30. What weight can be lifted by a screw that has an efficiency of 53.7% if
it is operated by a 50lb force at the end of a 30 in lever? The pitch of the
screw is ½ in.

A. 15,079 lbs C. 10,123 lbs

B. 12,221 lbs D. 16,245 lbs

31. A single bolt is used to lap join two steel bars together. Tensile force
on the bars is 20kN. Determine the diameter of the bolt in mm required if the
allowable shearing stress on it is 445755.18 torr.

A. 15.4 mm C. 19.2 mm

B. 20.7 mm D.30.6 mm

32. Surface treatment of high speed steel is by ______.

A. Carbon coating C. Second coating

B. Zinc coating D. Oxide coating

33. Which of the following statements is correct for the “brazed joint”?

A. STRONGER THAN A SOLDERED JOINT

B. WEAKER THAN A SOLDERED JOINT

C. THE SAME STRENGTH AS A SOLDERED JOINT

D. 3 TIMES AS STRONG AS A SOLDERED JOINT

34. Cast Iron is:

A. Best with aluminum for brake drums

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COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

B. The best materials for brake drums

C. Same as aluminum for brake drums
D. Not the best materials for brake drums

35. What is the use of flux in soldering?

A. KEEP THE SOLDER FROM RUNNING OFF THE METAL

B. KEEP THE METAL FROM GETTING TOO HOT

C. KEEP THE TIP OF THE SOLDERING IRON CLEAN

D. REMOVE AND PREVENT OXIDATION OF THE METALS

36. Which of the following would cause hot bearings?

A. IMPROPER OIL B. PROPER ALIGNMENT

B. DIRT IN WATER D. ALL OF THE ABOVE

37. Continuous stretching under load even if the stress is less than the yield
point

A. PLASTICITY C. CREEP
B. ELASTICITY D. DUCTILITY

38. A tool bit for cutting an American National thread should be ground with
what angle?

A. 45 DEGREES C. 60 DEGREES

B. 90 DEGREES D. 30 DEGREES

39. Percent of the heat developed in cutting is due to friction between the
tool and the workpiece is

A. APPROXIMATELY 50% C. APPROXIMATELY 10%

B. APPROXIMATELY 25% D. APPROXIMATELY 75%

40. Which of the following tools would be most useful when taking leads on
bearings?

A. DIVIDERS C. MICROMETER

B. OUTSIDE CALIPER D. CENTER GAGE

41. A single american thread power screw is to raise a load of 70kN. The screw
has a major diameter of 36mm and a pitch of 6mm. The coefficient of thread
friction and collar friction are 0.13 and 0.10 respectively. If the collar
mean diameter is 90mm and the screw turns at 60rpm, find the combined
efficiency of screw and collar.

A. 12.5% C. 12.01%

B. 13.1% D. 8.21%

42. The cylinder head of a 10 x 16in Freon compressor is attached by 10 stud

bolts made of SAE grade 5. The cylinder pressure is 878.137 cmHg. What is the
force on each bolt?

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COMPRE 2: WEEKLY EXAM (WEEK 4) THREADS, BOLTS, NUTS & MASTERY OF ELEMENTS.

A. 1571 lbs C. 1334 lbs

B. 1272 lbs D. 1400 lbs

43. What is the primary purpose of knurling?

A. SMOOTH MATERIAL C. ROUGHEN MATERIAL

B. POLISH MATERIAL D. SHARPEN MATERIAL

44. At what speed that carbon steel drill should be operated?

A. SPEED GREATER THAN THAT WHEN USING A HIGHSPEED DRILL

B. SPEED LESS THAN THAT WHEN USING HIGHSPEED DRILL

C. SAME SPEED AS THAT WHEN USING A HIGHSPEED DRILL

D. NONE OF THE ABOVE

45. Which of the following is a “must” for all hard hacksaw blades?

A. HAS A HARD BACK AND FLEXIBLE TEETH C.IT HAS A FLEXIBLE BACK AND HARD TEETH

B. IT HAS THE ENTIRE BLADE HARDENED D.IT WILL ONLY FIT A SOLID FRAME HACKSAW

46. Act of cutting out a piece of metal at a desired shape and size.

A. Blanking C. Dinking
B. Broaching D. Slitting

47. A line drawn through all the points at which teeth touch each other.

A. Angle of contact C. Path of contact

B. Arc of contact D. Arc of contact

48. What is the frictional kw acting on a collar loaded with 100 kg weight?
The collar has an outside diameter of 100 mm and an internal diameter of 40
mm. The collar rotates at 1000 rpm and the coefficient of friction between
the collar and the pivot surface is 0.15.

A. 0.723 C. 0.423

B. 0.523 D. 0.923

49. The cylinder head of a 10 x 16in Freon compressor is attached by 10 stud

bolts made of SAE grade 5. The cylinder pressure is 200psi. What size of stud
bolt should be used if SAE grade 5( ¼’’ – ¾’’) has the following stresses:
𝑆𝑝=85ksi, 𝑆𝑦=88 ksi

A. 0.1135 dm2 C. 0.344 dm2

B. 0.2921 dm2 D. 0.2255 dm2

50. What is the safe static tensile load for a M-32 x 2 – 6g bolt of mild
steel having yield stress of 466.3 Mpa and a safety factor of 1.5?

A. 190 kN C. 150 kN

B. 250 kN D. 205 kN

“Guidance can lead the way, but only you can unlock your full potential. Trust in your preparation.”