303.02.0068 KNORR-BREMSE 4-circuit protection valve

This heavy-duty grade component serves as a critical element in the pneumatic brake system, managing air distribution across multiple circuits to ensure safety and stability. The part is engineered to maintain precise pressure regulation, providing reliable protection during heavy commercial vehicle operations.

303.02.0068 is the OE-equivalent of the KNORR-BREMSE AE 4183 4-circuit protection valve used in heavy commercial vehicle brake systems. This component ensures seamless integration within the pneumatic circuit by managing various opening and closing pressures across its ports to maintain system integrity.

The technical configuration includes a main port (Port 1) with an M22x1,5 thread and several secondary ports (Ports 11, 12, 21, 22, 23, and 24) featuring M16x1,5 threads. It is designed to operate with a maximum pressure of up to 10 BAR, with specific opening pressures for ports 21 and 22 set at 7 BAR and closing pressures for ports 23 and 24 at 4,9 BAR.

Workshop technicians should ensure that all connections are secure and that the threading matches the specified M-sizes to prevent air leaks. Regular inspections of the port seals and pressure thresholds are recommended to maintain optimal braking performance in heavy commercial vehicle fleets.