8. FRAME
• The frame is the main part of a chassis. It is
the backbone of the vehicle. All other parts of
the chassis are mounted on the frame. It is a
rigid structure which forms a skeleton to hold
all major parts together.
13. Loads on chassis frame
1. Loads of short duration
2. Combined loads of momentary duration
3. Inertia loads
4. Impact loads
5. Load due to road camber
6. Load due to wheel impact
7. Static loads
8. overloads
14. DEFECTS IN FRAME
1. Misalignment in horizontal and vertical plane
2. Twisting of main frame and sub-frames
3. Buckled main frame and sub-frames
4. Bent side members and dumb iron
5. Broken or loose gusset plates and rivets
16. Body construction and its components
a). Structure: All load carrying elements are
defined as structure.
b). Finish: This group includes all unstressed
units such as bonnet, boot, lid, bumper etc.
c). Equipment: This group includes various parts
such as rim, seats, doors, window etc.
18. RESISTANCES TO VEHICLE MOTION
1. Air resistance:
a. Size of vehicle b. Shape
c. Speed d. Wind velocity
2.Gradient resistances:
The component of the vehicle’s weight which is
parallel to the plane of the road. This component
remains constant but independent of the vehicle
speed.
3. Miscellaneous resistance:
a. Road characteristics b. Tyre characteristics
c. Vehicle weight d. Vehicle speed
20. Drag force(Fx)
FX = CX ρv2A/2
Where
CX= drag coefficient
ρ= density of air
V= velocity of air
A = projected area of the vehicle viewed
from front
21. Lift force(Fz)
Fz = Cz ρv2A/2
Where
Cz= lift coefficient
ρ= density of air
V= velocity of air
A = projected area of the vehicle viewed
from front
22. Cross wind force(Fy)
• Pitching moment(MY): Is caused by the drag
force or lift force about y axis. This moment
makes the rear wheels lift off from the ground
and further it reduces the available traction.
• Yawing moment(Mz): Is caused by the cross
wind force (Fy) about Z.
• Rolling moment(My): is caused by the cross
wind force (Fy) about Z.
28. PISTON RINGS
Cast iron, alloy cast iron containing silicon and manganese, alloy
steels etc.
•piston rings are generally coated with chromium or cadmium.
29. CRANK SHAFT
carbon steel, nickel-chromium and other heat treated alloy
steels.