Analyze that the cylinder is unable to work and want to repair it?

When the cylinder is weak, you should first operate the walking and slewing mechanism to observe whether these two actions are powerful. If the movement of the walking or slewing mechanism is normal and the oil cylinder is weak, it can be analyzed and checked in the following order.

　　 Maintenance steps

　　 (1) Check whether the pilot pressure of the reversing valve of the control cylinder is normal. If the pilot pressure is low, there are three reasons: 1. The spring of the pilot valve is broken, and the spring should be replaced; 2. The valve core is stuck or jammed, and the valve core should be grinded or foreign matter removed; 3. The oil port should be cleared. Drop foreign objects.

　　 (2) If the pilot control oil pressure is normal, check whether the gap between the stem and the valve hole of the multi-way reversing valve meets the requirements. If the matching clearance between the valve stem of the multi-way reversing valve and the pottery hole is too large, the internal leakage is large, part of the oil flow flows back to the tank from the clearance, the flow to the cylinder is reduced, and there is some pressure loss, the valve stem and Valve body.

　　 (3) If the clearance between the valve stem and the valve hole meets the requirements, the pressure value can be measured at the oil cylinder inlet. If the oil cylinder reaches a certain position, the overflow pressure value of the secondary overflow valve is very low, you can increase the overflow pressure value of the secondary overflow valve: if the overflow pressure value of the secondary overflow valve cannot be adjusted to the rated value, you should Repair or replace the secondary relief valve.

At this time, everyone should pay attention, if the pressure of the secondary relief valve is increased to the specified value, the pressure of the oil cylinder inlet is still very low, it may be caused by the high pressure cavity and the low pressure cavity of the multi-way directional valve body. Damaged valve body. If the oil cylinder inlet pressure reaches the specified value of the overflow pressure of the overflow valve, and the moving speed of the oil cylinder is still slow, the fault may occur in the oil cylinder.

　　 (4) Failure in the cylinder will cause the cylinder to move slowly.

　　 In general, there are many failure points that can cause the cylinder to work weakly, and it involves pressure testing, adjustment, and replacement of related parts. This is also the root cause of many owners who have tried to repair by themselves but failed.