HYDRAULIC PROPORTIONAL TRACTOR BRAKE VALVE - OIL SYSTEM

Description:

The hydraulic proportional tractor brake valve is a component, through which the trailer can brake synchronously with the tractor.The valve is mounted on a tractor, that is connected to the hydraulic system, directional valves and existing braking system. The brake vavle is operated directly via the tractor brake pressure. Without pressure in the hydraulic system Y (tractor braking system) B is connected to T (tank) and P is connected to N (exceeding flow). As the flow in Y increases, the flow force activates the return spring (pilot), which closes the connection between B and T and establishes a connection between B and P. If is necessary, the flow is reduced between P and N, to create pressure on B. Max pressure on B port is 140 ± 10 bar. Load Sensing valve (LS) in mounted on B. 

In the first phase of braking, the valve can redirect the entire flow from the pump to the trailer brakes. So the oil on port N can be without oil a short time.

Caution when mounting:

The proportional valve is the safety element, that requires the most attention when inspecting and servicing the valve. Do not install the valve in front of other safety components (eg. controls). Usually, the valve is installed between the pump (constant flow or Load Sensing valve) and the control valve, in which there are no other safety components on this hydraulic circuit.