1. Frame And Suspension Fund.

Question 1

what is the main function of a frame in a heavy on-highway vehicle?

Answer 1

provide a platform to which all of the vehicle components are attached.

Question 2

the frame must be able to carry all of the loads placed on it without:

Answer 2

distorting, bending, cracking

Question 3

what is the Maximum Bending Moment?

Answer 3

the point on the frame at which the maximum force is concentrated

Question 4

most heavy vehicle frames consist of what?

Answer 4

two rails that run parallel to each other the entire length of the vehicle

Question 5

how are the two frame rails connected?

Answer 5

by cross-members that are welded, riveted or bolted in place

Question 6

the two rails with cross-members is called what type of frame?

Answer 6

ladder type frame

Question 7

frame rails are commonly shaped into what configurations?

Answer 7

channel
box
I-beam

Question 8

Channel frame rails consist of an upper and lower _____. the surface between these is known as the ____?

Answer 8

Flange

Web

Question 9

what frame is commonly used on trailers?

Answer 9

box

I-beam

Question 10

what frame commonly used on trucks?

Answer 10

Channel

Question 11

cross-members are connected to what part of the frame rails?

Answer 11

the web

Question 12

what is the purpose of the gussets?

Answer 12

provide resistance to frame weaving

Question 13

what is frame weaving?

Answer 13

the tendency for the frame to go out-of-square

Question 14

the strength of a vehicle frame depends upon?

Answer 14

the type of material used in its construction

the size and shape of the frame rails and cross-members

Question 15

the strength of frame material is expressed as the material __________

Answer 15

yield strength

Question 16

yield strength refers to the maximum:

Answer 16

amount of stress that the material can withstand without being permanently deformed

Question 17

the higher the yield strength the:

Answer 17

stronger the material

Question 18

heavy truck/tractor frames have a yield strength of around

Answer 18

110000 PSI

Question 19

what is resisting bending moment?

Answer 19

term used to express the overall strength of the frame.

Question 20

the suspension system must be able to preform the what functions?

Answer 20

1. secure the axles the to frame while maintaining alignment
2. support the weight of the vehicle and its cargo
3. cushion shock loads
4. allow the axle to move up and down relative to the frame

Question 21

what is sprung weight?

Answer 21

the weight of the vehicle and load above the point where the springs are attached.

Question 22

what is un-sprung weight?

Answer 22

weight of components located below the suspension

Question 23

what are 3 most common energy absorbing devices used truck/tractor/trailer

Answer 23

1. leaf springs
2. rubber cushion
3. air spring

Question 24

what are 4 common devices used to limit the amount of suspension movement?

Answer 24

1. axle stops
2. torque rods
3. rubber bushings
4. shock absorbers

Question 25

a suspension system with properly functioning shock absorbers provides:

Answer 25

1. Resistance to road impacts and wheel hop 2. Slower transfer of weight from one axle to another during accel. and braking 3. reduced suspension, steering and tire wear

Question 26

solid mount suspension system are best suited for vehicles that:

Answer 26

1. have a high centre of gravity 2. operate in an off-road environment 3. require long suspension travel

Question 27

what is another name for a equalizer beam?

Answer 27

walking beam

Question 28

what is spring rate in leaf springs?

Answer 28

refers to the load required deflect the springs a certain distance

Question 29

what is spring load range in leaf springs?

Answer 29

the maximum load carrying capacity of a spring

Question 30

what are two types of leaf springs available in heavy duty applications?

Answer 30

1. constant rate | 2. progressive rate

Question 31

what are two most frequently used are:

Answer 31

1. rolling lobe | 2. double convoluted

Question 32

what are 3 positions of ride height control valve?

Answer 32

1. Supply 2. Closed 3. Exhaust

Question 33

what is used to reduce effective spring length in progressive rate springs

Answer 33

cam bracket

Question 34

a pressure protection valve usually limits air from entering suspension till pressure reaches what pressure?

Answer 34

85 PSI

Question 35

the function of frame crossmembers is to:

Answer 35

provide rigidity and strength to a frame