There are many injuries caused by hydraulic cylinder leakage, which is one of the reasons that hydraulic cylinders cause various common failures, and is also a key element that endangers safety and environmental pollution. Therefore, sufficient attention should be paid.
The leakage of hydraulic cylinder includes two types of external leakage and external leakage. External leakage refers to the leakage of oil from the outside of the hydraulic cylinder barrel and cylinder head, cylinder bottom, oil hole, automatic exhaust valve, buffer adjustment valve, cylinder head and piston, etc., which is very easy to see from the outside world immediately. Internal leakage means that the working pressure oil in the high pressure cavity inside the hydraulic cylinder seeps into the bottom pressure cavity, which occurs at the connection between the piston rod and the cylinder cavity, and the internal thread of the piston rod and the piston. Internal leakage cannot be observed immediately. Whether it is internal leakage or external leakage, the key to the leakage is poor sealing and loose connections.
Poor sealing
Poor sealing can cause external and internal leakage. The reasons for poor sealing are:
1. Poor assembly line and damage to seals;
2. The assembly line has poor precision, large gaps, and the seals are squeezed and destroyed;
3. The seal is greatly damaged and the sealing effect is lost;
4. The direction of the sealing ring is reversed (the lip of the sealing ring faces the working pressure oil side), the sealing effect is invalid;
5. The sealing structure is unscientific, the working pressure exceeds the rated current, and the sealing effect is lost.
Poor fusion of joints
The key to poor fusion at the joint causes external leakage, and the reasons for poor fusion are:
1. When the cylinder barrel and the bearing end cover are connected with screws, the anchor bolts are not tightly tightened, part of the burrs and the assembly line are broken, resulting in poor fusion; the inner hole O-ring seal has a mutual matching gap;
2. When the cylinder barrel and the bearing end cover are connected by bolts, the rated torque is not achieved when the bearing end cover is tightened, or the sealing characteristics of the sealing ring are not good;
3. The pipe is loosened due to the pipe vibration at the oil inlet and outlet of the hydraulic cylinder.
Other reasons for hydraulic cylinder leakage
1. The cylinder tube is stressed, causing internal leakage;
2. Choose hydraulic cylinder with electric welding structure, because electric welding is not good enough to cause external leakage;
3. If the horizontal load is too large, every effort should be made to reduce the load.
