Function Of The Four-circuit Protection Valve

The brake system is divided into four interconnected and independent circuits. After the circuits are completely independent, it can ensure that when a circuit fails (breaks or leaks), it will not affect the normal operation and inflation of other circuits. At the same time, the air pressure of the failed circuit can be properly supplemented or even closed to play a protective role.
In other words, even if a certain air circuit fails and leaks, the four-circuit protection valve can still allow the remaining circuits to retain about 6.5 brake air pressures and provide braking effects.