Reasons for Malfunction in the Speed Control System of a 1000-ton Hydraulic Press
Reasons for Malfunction in the Speed Control System of a 1000-ton Hydraulic Press:
- 1.The throttle valve has a blocked throttle port, leading to either insufficient flow or unstable flow.
- 2.The speed control valve, especially the speed setting valve, has a spring that is too soft, resulting in a small pressure difference before and after the throttle valve, causing unstable flow in the speed control valve.
- 3.The pressure reducing valve in the speed control valve is stuck, causing the pressure difference before and after the throttle valve to vary with external load.
- 4.The pressure reducing valve in the speed control valve is stuck in the open position, causing a decrease in flow through the throttle valve when the load increases.
The hydraulic speed control valve has the advantage of good flow stability but has the drawback of significant pressure loss. It is often used in fixed pump throttle speed control systems, providing substantial load variation and high speed control precision. Sometimes, it is utilized in volume-adjustable speed control hydraulic systems with variable pump oil supply. In fixed pump supply throttle control hydraulic systems, it can be combined with a pressure reducing valve to form a series of throttle valves and parallel throttle valve speed control circuits.