The phenomenon that the hydraulic cylinder cannot move normally often happens on the hydraulic cylinder that has just been installed. When troubleshooting this fault, first look for the reason from the outside of the hydraulic cylinder: whether the resistance of the moving parts of the hydraulic cylinder is too large, whether there is stuck, wedged or against other parts; Whether the oil inlet pressure reaches the specified value. After the exclusion of external factors, further check the internal cause of the hydraulic cylinder, and take the corresponding elimination method. The reasons why the hydraulic cylinder cannot operate and the elimination methods are analyzed as follows:

The resistance of moving parts is too big

Solution:

1) eliminate problems such as clamping and wedge tightness in the actuator.

2) improve the conduction and lubrication of moving parts.

2. The oil inlet pressure is too low to reach the specified value

Solution:

1) check the leakage of the oil pipeline system and eliminate the leakage.

2) check whether the sealing ring at the piston and piston rod is damaged, aged or loose.

3) check whether the hydraulic pump and pressure valve are in trouble.

Three, the oil did not enter the hydraulic cylinder

Solution:

1) check whether the oil pipe, oil line and especially the hose joint have been blocked.

2) check whether the seal between the cone valve and the seat of the overflow valve is good.

3) check whether the solenoid valve spring is damaged or the solenoid coil is burnt out; Whether the oil switch is not sensitive.

Four, the hydraulic cylinder itself sliding parts fit too tight, sealing friction force is too large

Solution:

1) H8 / f8 coordination shall be selected between piston rod and guide sleeve.

2) check whether the size of the sealing ring is processed strictly according to the standard.

3) if v-shaped sealing ring is used, the friction force of sealing should be adjusted to a moderate degree.

5. Due to the improper design and manufacturing, the effective working area of the piston under the action of pressure oil is too small when the piston travels to the end point and then returns

Solution:

Improve design and remanufacture.

Six, piston rod to bear the transverse load is too large, especially do not force or cylinder, bite dead

Solution:

1) when installing the hydraulic cylinder, the axis position of the cylinder should be consistent with the movement direction.

2) make the load borne by the hydraulic cylinder pass through the cylinder axis as far as possible to avoid eccentricity.

3) level of long hydraulic cylinder rotates, the piston rod because of the weight of the deflection, the guide sleeve and the piston to produce partial load, lead to damage of cylinder head seal, oil spills, sleep disorder within the cylinder piston, which can take the following measures: to increase piston planning adjustment live round convex processed into drum, beyond the Great Wall can make piston self-aligning, improve the stress state, in order to reduce and avoid the cylinder; The connection of piston and piston rod adopts spherical joint.

The back pressure of the hydraulic cylinder is too big

Solution: reduce back pressure.

One of the hydraulic cylinder can not move the important reason is that the oil inlet pressure is too low, that is, the work pressure is insufficient. Causes of insufficient working pressure of the hydraulic system, mainly hydraulic pump, drive motor and pressure regulating valve fault, other reasons include: filter plug, oil path diameter is too small, oil viscosity is too high or too low; Excess air entering the oil; Serious pollution; Wrong connection of pipeline; The pressure gauge is damaged.