Undercarriage Systems Fundamentals and Service Part A

Question 1

1. An undercarriage system must provide a balance between adequate traction, machine stability and satisfactory load carrying capacity.
   a) true
   b) false

Answer 1

1.

a) true

Question 2

2. The load carrying capacity of an undercarriage is determined mostly by the:
   a) height of the grouser.
   b) weight of the machine.
   c) width of each track shoe.
   d) number of carrier rollers.

Answer 2

2. c) width of each track shoe.

Question 3

3. The stability of the machine is more important when the machine is an excavator rather than a crawler tractor equipped with a dozer.
   a) true
   b) false

Answer 3

3.

a) true

Question 4

4. A tracked crane is more suitable for:
   a) lifting heavy loads which are quite a distance from the machine.
   b) digging into the side of a dirt pile.
   c) lifting heavy loads that are very near to the machine.
   d) pulling heavy loads of material that are located some distance from the machine.

Answer 4

4. c) lifting heavy loads that are very near to the machine.

Question 5

5.   Identify six (6) major components that comprise a typical undercarriage system.
(
a)
b)
d)
e)
f)

Answer 5

5. Any six (6) of the following are correct.
   a) track frames
   b) pivot shaft and equalizer bar
   c) track chain
   d) track and carrier rollers
   e) drive sprocket
   f) idlers
   g) track tension and recoil mechanisms
   h) protective devices (guards)

Question 6

6. Explain the main function of the track frame.

Answer 6

6. The heavy track frame provides a solid support for the remaining undercarriage components. The track frame also absorbs shock loads caused by collisions between the track assembly and immobile objects.

Question 7

7. The following type(s) of track links are available for use as required by a specific
   track chain application:
   a) split master links.
   b) flush mount
   c) one-piece links.
   d) interlocking links.
   e) any of the above links could be used in track

Answer 7

7. e) any of the above links could be used in track chains.

Question 8

8. A master pin and a split master link have one function in common with each other.
   Explain that function.

Answer 8

8. The master pin and the split master link are both used to hold the track chain together. The master pin must be removed to split the track chain while the split link must be disconnected in order to split the track chain.

Question 9

9. A machine is operating on soil that could cause soil packing in and around the track chain. Identify the type of track shoe you would recommend for this type of operating condition.

Answer 9

9. When soil packing is a problem the machine should be equipped with open center track shoes.

Question 10

10. A low mount final drive and drive sprocket system could be used on:
    a) a crawler tractor.
    b) an excavator.
    c) a front end loader.
    d) a shovel
    e) any of the above machines are correct.

Answer 10

10. e) any of the above machines are correct.

Question 11

11. Explain the major difference between pedestal (carrier) rollers and track rollers.

Answer 11

11. Carrier rollers are mounted on pedestal members on top of the track frame and support the weight of the top track. Track rollers are mounted on the bottom of the track frame and help support the weight of the machine.