When the open or longitudinal center valve is used for the loop transmission valve requiring test pressure, there must be a method to maintain the pressure when the valve is in the middle position. One way is to install a back pressure check valve in the oil tank pipeline. The check valve maintains a back pressure of 50 psi.

Low pressure contraction

The electrification of the electromagnetic telescopic cylinder corresponds to the maximum pressure set by the main system pressure relief valve. The frustrated solenoid valve retracts the cylinder and keeps it retracted under the revised air pressure setting of the test relief valve. During the extension of the hydraulic cylinder, the check valve prevents the test pressure reducing valve from working.

Two pressure reducing valves

Use two to give two working pressures at the pressure reducing valve of the circuit. During the cylinder stroke, the low pressure relief valve limits the system pressure. Maximum news tonnage limit of finished high-pressure valve during downstroke. Use low-pressure peace of mind in the stroke, and save power by supporting the cylinder with low-pressure fluid. Corrected air pressure

In the system with pump, the corrected air pressure of the loop branch can only be obtained through the pressure reducing valve. This loop is a typical welding machine, and the required clamping force will be set by the pressure reducing valve, and the reduced force will flow upstream.