1. When the pressure reducing valve, the outlet pressure is controlled to ensure that the outlet pressure is stable. The pressure reducing valve of the hydraulic press is connected in series with the load. The pressure regulating spring chamber has an external drain port, which adopts negative feedback of the outlet pressure. The valve port is normally open when not working. The overflow valve is controlled by the inlet pressure to ensure that the inlet pressure is a fixed value.
2、400 ton hydraulic pressThe valve port of the pressure reducing valve is normally open, and the oil inlet and outlet ports are normally connected; the valve port of the overflow valve is normally closed, and the oil inlet and outlet ports are not normally open.
3. The pilot stage of the pressure reducing valve has a separate drain port (leakage); the leakage oil of the overflow valve spring chamber can be discharged to the outlet through the inner flow passage of the valve body.
4、400 ton hydraulic pressThe outlet of the overflow valve is connected to the oil tank, and the leaked oil in the spring cavity of the pilot valve is discharged to the outlet through the flow passage in the valve body; the pressure oil at the outlet of the pressure reducing valve goes to the actuator for work, the pressure is not zero, and the leaked oil of the pilot valve spring is separated The oil is led back to the oil tank. The pressure reducing valve is used in the hydraulic system to obtain the secondary oil path where the branch pressure p2 is lower than the system pressure p1, such as the clamping circuit, the lubrication circuit and the control circuit.