Hydraulic reversing valve return spring force not only insufficient, but the existence of skew phenomenon, resulting in spool valve failed to return to the original position after the power is off, then open the spool amount is too small, the valve of the oil liquid throttling effect.
  The initial action of the cylinder is slow, the viscosity of the hydraulic fluid is large and the activity is poor when the temperature is low, which results in the slow motion of the hydraulic cylinder. If the outside temperature is indeed too low, it is possible to use the heater or the corresponding insulation measures to promote the oil temperature at startup.
  Should check the contamination of oil; check dirt or colloid sediment whether stuck spool or valve hole, and check the wear of the valve body. In the control pipeline, the throttling resistance may be too large, the flow valve is improperly adjusted, the control pressure is different, and the pressure source is disturbed.
  The hydraulic pressure of hydraulic press is too low.
  Hydraulic pressure machine, piston rod and cylinder blocked or hydraulic cylinder blocked. The method of covering is to replace the hydraulic oil with good viscosity and temperature resistance in time. If the outside temperature is indeed too low, it is possible to use the heater or the corresponding insulation measures to promote the oil temperature at startup. When the flow valve or the direction valve core is jammed or the valve hole is blocked, the hydraulic cylinder is very prone to malfunction or malfunction at this time. The method of covering is to replace the hydraulic oil with good viscosity and temperature resistance in time. At this point, check whether the piston and piston rod seal is too tight, whether to enter the dirt and glial sediment; whether the piston rod and cylinder axis line is in, and whether the damaged parts and seals are invalid. At this point, no matter how to operate, the hydraulic cylinder does not move or move what is micro.
  When the temperature of hydraulic press is low, the viscosity of hydraulic fluid is large and the activity is poor, which leads to the slow action of hydraulic cylinder. The pressure source should be checked to ensure that the pressure is adjusted to the system value.