Air Brakes

Question 1

What is the primary function of the service brake chamber?

Answer 1

To actuate the brake shoes through slack adjuster and S-cam

The service brake chamber is essential in the braking system for controlling the vehicle’s speed and stopping power.

Question 2

What determines the braking force in a brake chamber?

Answer 2

The chamber diaphragm surface area

A larger diaphragm surface area increases the braking force applied.

Question 3

How is the braking force (BF) calculated?

Answer 3

BF = P x A

Where P is pressure and A is area.

Question 4

What are the two types of brake shoes?

Answer 4

• P-type
• Q-type

P-type shoes have a closed end, while Q-type shoes have an open-ended saddle.

Question 5

What is a characteristic of the P-type brake shoe?

Answer 5

End is closed

This design is the most common type of brake shoe.

Question 6

What is the function of the S-cam in the braking system?

Answer 6

To expand brake shoes

The S-cam rotates to push the brake shoes outward against the brake drum.

Question 7

What are the two types of cams mentioned?

Answer 7

• S-cam
• Flat camshaft

Each type of cam functions differently in the brake system.

Question 8

True or False: The flat camshaft provides a significant delay in brake application.

Answer 8

True

The flat camshaft has a design that allows for a slight delay in the application of the brakes.

Question 9

Fill in the blank: The leading shoe develops _______ while departing.

Answer 9

[self-energizing force]

This force helps in enhancing the braking efficiency.

Question 10

What is the role of the slack adjuster in the braking system?

Answer 10

To maintain proper adjustment of the brake shoes

This ensures that the brake shoes engage properly with the brake drum.

Question 11

Where is the Air Brake Pot located on a vehicle?

Answer 11

Mounted to bracket, melded to axle

Proper mounting is crucial for the functionality and safety of the braking system.

Question 12

What happens when the S-cam rotates?

Answer 12

It expands the brake shoes

This action is essential for effective braking.

Question 13

How does the brake drum interact with the brake shoes?

Answer 13

The brake shoes press against the drum to create friction

This friction is what slows down or stops the vehicle.

Question 14

What is the function of rollers in the braking system?

Answer 14

To retract the brake shoes

Rollers assist in the movement of the brake shoes back into position when the brakes are released.