Hydraulic press speed control system failure reasons

Hydraulic press is a machine with liquid as the working medium, mainly composed of the main engine, power system and hydraulic control system three parts, it is widely used in the production and manufacturing industry, then the best machine if long-term use will be a problem. The speed regulation of the hydraulic system is an important part of the hydraulic pump station, the speed of the actuator is not normal, the hydraulic machinery can not work. So what are the main failures of the speed control system and their causes? Follow Zhengzhou Jinxi hydraulic system manufacturers to have a look:

1. The actuator (hydraulic cylinder, hydraulic motor) has no small feed factor

1) The saving port of the saving valve is blocked, resulting in no small flow or small flow instability;

2) The spring of the regulating valve is too soft, so that the pressure difference before and after the saving valve is too low, resulting in the small flow through the regulating valve is unstable;

3) The pressure reducing valve in the speed control valve is stuck, and the pressure difference before and after the saving valve changes with the external load, which is often seen because the load is small when the small feed, resulting in the increase of the small feed.

2. Factors that significantly reduce the feed speed when the load is added

1) The leakage of one or several components in the hydraulic cylinder piston or system increases significantly with the increase of load and pressure;

2) The pressure reducing valve in the speed control valve is stuck in the open position, and the flow rate through the saving valve is reduced when the load is added.

3. The creeping factor of the executive mechanism

1) Air enters the hydraulic press system;

2) Due to the poor smoothness, the guide rail is not parallel to the axis of the hydraulic cylinder, the piston rod seal pressure is too tight, the piston rod bending deformation and other factors, resulting in the hydraulic cylinder working stroke friction changes greatly and resulting in crawling;

3) In the oil-saving speed regulation system, the hydraulic cylinder has no back pressure or lack of back pressure, and the external load changes, resulting in the cylinder speed change;

4) hydraulic pump; The flow pulsation is large, and the pressure pulsation of the system is formed by the oscillation of the relief valve, which is caused by the shaking of the input pressure oil of the hydraulic cylinder.

5) The valve port of the saving valve is blocked, the system leakage is unstable, and the pressure reducing valve in the speed control valve is not sensitive, resulting in unstable flow and creeping.