Materials and Fastening Devices

Question 1

I. Ferrous metals are metals that:

a) deflect magnetism.
b) do not corrode easily.
c) have an iron base.
d) are extremely hard and brittle.

Answer 1

c) have an iron base.

Question 2

2. Threads for cast iron are usually a coarse thread.
   a) true
   b) false

Answer 2

a) true

Question 3

3. Which of the following has the lowest melting point? a) aluminum
   b) brass
   c) copper
   d) lead

Answer 3

d) lead

Question 4

4. Choose the statement which best describes elasticity. a) Elasticity is the ability of a material to resist deflection. b) Elasticity is the ability of a material to be compressed, yet maintain its shape.
   c) Elasticity is the ability of a material to be stretched and still return to its original shape.
   d) Elasticity is the maximum amount a material can be heated without permanent deformation

Answer 4

c) Elasticity is the ability of a material to be stretched and still return to its original shape.

Question 5

5. When steel is heated to a high temperature and cooled slowly, the metal will be:
   a) in a very hard brittle state.
   b) in a softened state, easy to work.
   c) suitable for use as a chisel.
   d) warped and out of shape.

Answer 5

b) in a softened state, easy to work.

Question 6

6. Vulcanizing rubber refers to:
   a) melting raw rubber and allowing it to cool slowly.
   b) heating raw rubber with sulfur to alter its properties. c) drawing the rubber from the rubber tree.
   d) a treatment to help the rubber become stiffer and stronger.

Answer 6

b) heating raw rubber with sulfur to alter its properties.

Question 7

7. What is the health hazard when working with asbestos and fiberglass?

Answer 7

7. Both are hazardous when inhaled.

Question 8

8. Which of the items listed below would be best to form a gasket?
   a) gasket sealant
   b) fiberglass
   c) thread locker
   d) silicone

Answer 8

d) silicone

Question 9

9. Nylons are being used in industry as a replacement for metal.
   a) true
   b) false

Answer 9

a) true

Question 10

10. A cap screw with a thread pitch of 1/24th inch has:
    a) 12 threads per inch.
    b) 1/24th thread per inch.
    c) 24 threads per inch.
    d) 18 threads per inch.

Answer 10

c) 24 threads per inch.

Question 11

11. Thread series refers to the:
    a) degree of fit of the threads.
    b) markings on the bolt head.
    c) length of a fastener.
    d) type of thread: UNC, UNF, UNEF or NPT.

Answer 11

d) type of thread: UNC, UNF, UNEF or NPT.

Question 12

12. Explain by short answer or sentence form, how tensile strength is indicated on imperial and metric fasteners.

Answer 12

Imperial fasteners have lines. The number of lines plus two is the tensile strength. Metric fasteners have numbers indicating their class: 4.8, 8.8, 10.9.

Question 13

13. What do the numbers 10-24 refer to in regards to machine screws?

Answer 13

10 indicates the diameter or size; 24 indicates the number of threads per inch.

Question 14

14. Lock washers are not suitable for use with which of the following?
    a) stainless steel
    b) aluminum
    c) mild steel
    d) steel

Answer 14

b) aluminum

Question 15

15. A fastener with six (6) radial marks on the head has a tensile strength of:
    a) SIX.
    b) four.
    c) eight.
    d) seven.

Answer 15

c) eight.

Question 16

16. A fastener has resistance going into a threaded hole. This resistance to turning is called: a) torque turn and is added to the full torque.
    b) is not a factor as full torque covers it.
    c) thread locker.
    d) run down torque and must be added on to the full torque.

Answer 16

d) run down torque and must be added on to the full torque.

Question 17

17. What is another name for a Woodruff key?

Answer 17

A half moon key

Question 18

18. Besides securing and driving components, what other function is performed by a helical spline? Explain in one sentence.

Answer 18

A helical spline offsets end or axial thrust.

Question 19

19. Applying a lubricant to the threads of a fastener and using a dry torque specification will:
    a) increase the torque required to tighten it.
    b) decrease the clamp load compared to dry threads.
    c) increase the clamp load compared to dry threads.
    d) not affect the torquing procedure.

Answer 19

c) increase the clamp load compared to dry threads.

Question 20

20. Split and roll pins should be installed with what kind of a tool? Explain in one sentence.

Answer 20

Use a roll pin punch for the size of pin.

Question 21

21. Set screws use the same sizing standard as:
    a) sheet metal screws.
    b) machine screws.
    c) lag screws.
    d) rivets.

Answer 21

b) machine screws.

Question 22

22. Aerobic sealers are those that require air to enable them to cure.
    a) true
    b) false

Answer 22

A true

Question 23

23. Explain the function of a snap ring.

Answer 23

Snap rings are placed within a groove on a shaft or housing and provide a surface against which a component may ride.

Question 24

24. If a fastener with thread locker or locktite is difficult to remove, you should:
    a) use a hammer and chisel to cut it off.
    b) use a cutting torch to cut it off.
    c) use a nut splitter.
    d) apply heat.

Answer 24

d) apply heat.