Truck/trailer Air Brake System Components

Front 1

When an air brake compressor piston is on its compression stroke, the inlet valve

Back 1

Is closed and the discharge valve is open

Front 2

When the compressor is in it’s unloaded cycle

Back 2

The inlet valves are held open

Front 3

The governor controls maximum air system pressure by

Back 3

Putting the compressor in the loaded cycle

Front 4

The automatic drain valve drains moisture and contamination from the reservoir

Back 4

Any drop in reservoir pressure

Front 5

Air brake antifreeze is used in the air brake system to

Back 5

Prevent moisture in the system from freezing

Front 6

Desiccant type air dryers rely on

Back 6

Beads that absorb moisture vapour from the air stream

Front 7

Single check valves are installed in the inlet line both the primary and the secondary service reservoirs brocade they

Back 7

Prevent air loss in the event of a failure in the other reservoirs

Front 8

The function of the safety valve is to

Back 8

Limit air pressure buildup in the event of a governor failure

Front 9

CMVSS 121 states the minimum pressure at which the low pressure warning devices must warn the operator is

Back 9

60psi

Front 10

Nylon air brake tubing should not be used where it may be exposed to

Back 10

High temperatures

Abrasion and wear

Excessive movement

Front 11

In the released position, the inlet/exhaust valves of the dual-circuit brake valve are in the following condition

Back 11

Inlets are closed and the exhausts are open

Front 12

The dual-circuit brake valve holds its inlet and exhaust valves closed

Back 12

When the valve is in its balanced position

Front 13

The function of the relay valve in the primary brake circuit is to speed up the

Back 13

Application and release of the primary service brakes

Front 14

When the dual-circuit brake valve delivers 20psi of primary service application pressure, a relay valve with a cracking pressure of 2.5psi reacts by sending

Back 14

17.5psi to the primary brake chambers

Front 15

A type 24 brake chamber has a

Back 15

Area of 24in squared

Front 16

During normal brake applications, the secondary piston of the dual-circuit brake valve is applied by

Back 16

Primary service air pressure

Front 17

The function of the quick release valve in the secondary brake circuit is to

Back 17

Speed up the release of the secondary service brake

Front 18

What is the purpose of the primary circuit

Back 18

To allow the operator to control the application and release of the drive axle brakes

Front 19

3 components of the primary circuit

Back 19

Dual circuit brake valve

Service relay valve

Drive axle brake chambers

ABS modulators

Primary reservoir

Limes and hoses

Front 20

What circuit is closest to the pedal assembly

Back 20

Primary circuit

Front 21

What controls the secondary piston during a normal stop

Back 21

Primary air through the orifice

Front 22

Relay valve

Back 22

Quick application and release of the service brakes

Front 23

Cracking pressure

Back 23

The amount of air to get the piston to move downward and open up the inlet in a relay

Front 24

Function of a service brake chamber

Back 24

Converts compressed air to mechanical force

Front 25

Secondary circuit

Back 25

To allow the operator to control the application and release of the steer axle brakes

Front 26

3 components of the secondary circuit

Back 26

Duel circuit brake valve

Quick release valve

Front service chamber

Lines and hoses

ABS modulators

Front 27

Quick release valve

Back 27

Quick release of air from the service chamber