BENDIX SR-5 TRAILER SPRING BRK VALVE - User Manual

1
®
SD-03-4516
Bendix
®
SR-5
™
Trailer Spring Brake Valve
FIGURE 1 SR-5
™
TRAILER SPRING BRAKE VALVE
*SHOWN WITH OPTIONAL ANTI-COMPOUNDING COVER
SR-5
™
VALVE
IDENTIFICATION
HOLE
1/4” NPT TRAILER
SERVICE
1/4” NPT
TRAILER SUPPLY
EXHAUST
COVER*
1/4” NPT
SERVICE
RESERVOIR
(2)
3/8” NPT
DELIVERY (4)
1/2” OR 3/4” NPT
SPRING BRAKE
RESERVOIR
PRESSURE
PROTECTION
VALVE
DESCRIPTION
The SR-5
™
valve is a reservoir-mounted trailer valve that can
control up to four spring brake actuators during parking or
emergency applications. It has the following capabilities:
• Automatically applies trailer spring brakes in the event of
a breakaway or trailer supply line failure.
• Protects trailer reservoir(s) air pressure in the event of a
breakaway or trailer supply line failure.
• Allows no automatic trailer spring brake application with
air pressure loss in trailer reservoir(s).
• Allows the trailer spring brakes to be applied and released
repeatedly with a failed trailer reservoir(s):
• Optional anti-compounding-prevents an overriding service
brake signal while the trailer supply line is at atmospheric
pressure.
• Does not allow service system charging if a failure occurs
in the parking brake circuit.
PORTS
1 - 1/2" or 3/4" NPT Spring Brake Reservoir Mounting
(SPR BK RES)
1 - 1/4"-18 NPT Trailer Supply (TRL SUP)
1 - 1/4"-18 NPT Trailer Service (TRL SER)
4 - 3/8"-18 NPT Delivery (DEL)
2 - 1/4"-18 Service Reservoir (SERV RES)
1 - Exhaust (EXH)
The SR-5
™
valve appears very similar to the SR-2
™
valve.
Both valves consist of a die-cast aluminum body and cover,
pressure protection valve, and reservoir-mounting nipple.
However, Figure 1 notes the distinguishing characteristic of
the SR-5
™
valve–a hole drilled into the flat surface between
the pressure protection valve and the body.

BENDIX SR-5 TRAILER SPRING BRK VALVE Specifications

General

Type	Trailer Spring Brake Valve
Model	SR-5
Manufacturer	Bendix
Control Port	1/4" NPT
Supply Port	1/2 inch NPT
Delivery Ports	3/8 inch NPT
Function	Controls the application and release of trailer spring brakes

Summary

Ports

Operation

Charging Below 70 PSI

Explains air flow and piston movement during charging below 70 PSI.

Charging Above 85 PSI

Explains air flow and reservoir charging above 85 PSI.

Park Application

Park Release with Trailer Charged

Optional Anti-Compounding Feature

Anti-Compounding Explanation

Explains how the SR-5T™ valve prevents brake compounding.

Failed Trailer Reservoir

General Safety Guidelines

Vehicle Parking and Wheel Blocking

Instructions on parking, applying brakes, and blocking wheels.

Engine Shutdown and Key Removal

Procedures for engine shutdown and ignition key removal.

Component Handling and Procedure Understanding

Guidelines for handling components and following procedures.

Air Pressure Release and Reservoir Draining

Procedures for draining air pressure from reservoirs.

Electrical System Deactivation

Instructions for safely deactivating the electrical system.

Adhering to Recommended Pressures

Warning against exceeding specified pressure limits.

Hose;Line Connection and Pressure Depletion

Precautions for connecting/disconnecting lines with pressure.

Operational and Leakage Tests

Reservoir Pressure Build-up Test

Exhaust Port Leak Test

Spring Brake Application and Supply Line Leak Test

System Stabilization and Drain Cock Leak Test

Valve Functionality and Leakage Assessment

Disassembly

Piston and Spring Assembly Disassembly

Control Piston and Related Parts Removal

Cleaning and Inspection

Parts Wear and Housing Bore Inspection

Assembly

Check Valve and Reservoir Fitting Assembly

Control Piston and Cover Assembly

Piston, Spring Retainer, and Exhaust Port Assembly