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Fault diagnosis and treatment of hydraulic cylinder

Fault diagnosis and treatment of hydraulic cylinder

1, malfunction or malfunction

The reasons and treatment methods are as follows:

(1) the valve core is jammed or the valve hole is blocked. When the flow valve or the direction valve spool is jammed or the valve hole is blocked, the hydraulic cylinder is prone to malfunction or malfunction. You should check the pollution of oil or dirt; check whether the spool stuck gum deposit or blockage of the valve hole; wear check valve, filter cleaning and replacement system, cleaning the tank, replacing the hydraulic medium.

(2) the piston rod is stuck with the cylinder or the hydraulic cylinder is blocked. At any rate, the hydraulic cylinder does not move or act very little. You should check the piston and piston rod seal is too tight, whether to enter the dirt and colloid sediment: axis of the piston rod and the cylinder is right, wearing parts and seal failure, the load is too big.

(3) the hydraulic system controls the pressure too low. In the control pipeline, the throttling resistance may be too large, the flow valve is improperly adjusted, the control pressure is not appropriate, and the pressure source is disturbed. The pressure source shall be checked to ensure that the pressure is adjusted to the specified value of the system.

(4) air enters into the hydraulic system. This is mainly because of leaks in the system. At this point, you should check the hydraulic tank level, hydraulic pump suction side seals and pipe connections, oil filter is too dirty. In this case, the hydraulic fluid shall be added to handle the seal and pipe connections, cleaning or replacing the coarse filter.

(5) the initial movement of hydraulic cylinder is slow. When the temperature is low, the viscosity of hydraulic oil is large and the flow is poor, which makes the hydraulic cylinder move slowly. The method of improvement is to replace the hydraulic oil with good viscosity and temperature. At low temperature, the heater can be heated by means of a heater or by heating the machine itself, and the normal operating temperature of the system should be kept at about 40 degrees centigrade.

2, the work can not drive the load

The main reasons are the stop of piston rod, the lack of thrust, the decrease of speed and the instability of the work:

(1) internal leakage of hydraulic cylinder. Hydraulic cylinder leakage includes hydraulic cylinder seal, piston rod and sealing cap seal and piston seal are excessive wear and tear caused by leakage.

The sealing leakage of the piston rod and the sealing cap is caused by wrinkles, extrusion, tear, wear, aging, deterioration, deformation, etc., and new seals should be replaced at this time.

The main reason for excessive wear of piston seal is improper adjustment of speed control valve, resulting in excessive back pressure and improper installation of seal or hydraulic oil pollution. Followed by the assembly of foreign materials access and sealing materials of poor quality. The consequences are slow, weak, can also cause serious damage to the piston and cylinder, "cylinder" phenomenon. The method is to adjust the speed control valve, and shall do necessary operation and improvement in comparison with the installation instructions.

(2) leakage of hydraulic circuit. Leakage of valves and hydraulic lines is included. The method of inspection is to check and eliminate the leakage of the hydraulic connection pipe by operating the reversing valve.

(3) hydraulic oil flows back to the tank through the overflow valve. If the overflow valve into the dirt, stuck valve core, so that overflow valve often open, hydraulic oil will flow through the overflow valve bypass directly into the tank, resulting in no oil into the hydraulic cylinder. If the load is too large, the regulating pressure of the relief valve has reached the maximum rating, but the hydraulic cylinder still can not get the thrust needed for the continuous action without action. If the adjustment pressure is low, but because the pressure is insufficient, still does not carry the needed vertebra force, displays the thrust to be insufficient. The relief valve shall be checked and adjusted at this time

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American Torque Wrench, Inc 803 Summer Park Drive Suit 

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