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Trailer regulate

Valve The live independence trailer manage valve (fig. 7-48) offers the operator with regulate of the trailing load at all times. This valve features in the very same manner together the pedal valve other than that the manage is turned, rather than depressed, to run the valve.

Quick-Release Valve

The quick-release valve (fig. 7-49) exhausts brake room air press and increases brake release by reduce the distance the air would need to travel ago to the brake valve exhaust port.

When the brakes are engaged, air from the brake valve enters right into the quick-release valve, forcing the diaphragm down and closing off the exhaust port. This action allows air push to rush through the quick-release valve outlet ports come the wheel brake chambers. Once the brakes room released, the wait pressure above the quick-release diaphragm is


Figure 7-48. - Trailer control valve.


Figure 7-49. - Quick-release valve.

exhausted in ~ the brake valve. As air pressure above the diaphragm is released, the air pressure listed below the diaphragm raises turn off the exhaust port. This activity allows the air in the brake chambers to exhaust in ~ the quick-release valve.

When waiting is leaking indigenous the system, a leakage test can determine if there is waiting leaking at the quick-release valve. The leakage test is performed with the brakes applied and also coating the exhaust port v soapsuds. If air bubbles form, this is a sign of a defective valve, which deserve to be corrected by one of two people cleaning and also replacing worn parts or by instead of the unit. Dirt, worn diaphragm, or a worn seat reasons leakage.

Combined-Limiting and Quick-Release Valve

The combined-limiting and also quick-release valve (fig. 7-50) is provided in combination with a two-way examine valve in the waiting brake mechanism of trucks and also tractors. The combined-limiting and quick-release valve is interchangeable interchangeable in mounting with the quick-release valve and serves the same objective with the additional function of offering an automatically reduction that front-wheel brake pressure, at the choice of the operator, ~ above slippery roads.

Tractor security Valve

The major purpose of the tractor protection valve (fig.

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7-51) is to defend the tractor air brake device under trailer breakaway conditions and under problems where serious leakage develops in the tractor or trailer.