Pilot operated relief valve Mining machinery relief valve RSDC-LAN

Pilot relief valves are available in a variety of configurations. A typical three-section concentric structure pilot relief valve, which is composed of two parts: pilot valve and main valve.

The taper pilot valve, the damping hole (fixed throttle hole) on the main valve spool and the pressure regulating spring together constitute the pilot half-bridge partial pressure negative feedback control, which is responsible for providing the main stage command pressure after the pilot valve pressure regulation to the upper chamber of the main valve spool. The main spool is the comparator of the main control loop. The upper end face acts as the command force of the main spool, while the lower end face acts as the pressure measuring surface of the main loop and acts as the feedback force. The resultant force can drive the spool, adjust the size of the overflow port, and finally achieve the purpose of regulating and regulating the pressure of the inlet pressure P1.

YF type three-section concentric pilot relief valve structure Figure 1-(- taper valve (pilot valve); 2 - Cone seat 3 - valve cover; 4 - Valve body; 5 - damping hole; 6 - main valve core; 7 - Main seat; 8 - main valve spring; 9 - pressure regulation (pilot valve) spring; 10 - adjusting screws; 11 - Adjust the handwheel.

Hydraulic system cartridge valve advantages:

①No high-speed reversing impact:

    this is the most prone to headache in high-power hydraulic systems. Because the cartridge valve is a compact conical valve structure, the control volume is small when switching, and there is no "positive cover" concept of the slide valve, so it can be switched at high speed. By taking some measures for the components of the pilot part and adapting to the transition state control during the switching process, the reversing impact can be greatly reduced during the switching.

② With high switching reliability:

    the general cone valve is difficult to cause bad action due to dirt, small pressure loss, small heat, and the spool has a long guide part, which is not easy to produce skew stuck phenomenon, so the action is reliable.

③Because the cartridge logic valve has been standardized at home and abroad, whether it is the international standard ISO7368, Germany DIN 24342 and China (GB 2877 standard) have stipulated the world's common installation size, which can make the cartridge parts of different manufacturers interchangeable, and does not involve the internal structure of the valve. This also gives the hydraulic valve design work to leave a broad scope for development.