How to deal with oil leakage failure of seals

When oil leakage is found in the seal, check whether there are abnormal phenomena in the seal area first. Usually, there are two situations to judge.

Class: when the seal is not abnormal

1. Oil leakage at low pressure and no leakage at high pressure is caused by poor surface roughness of assembly. ----- improves the surface roughness to 3.2~6.3umry with a lower hardness seal

2. The oil ring of the piston rod becomes larger, and every stroke will drop a few drops of oil, which causes the lip of the dust ring to scrape off the oil film and replace the type of the dust ring.

3. There are two reasons for oil leakage at low temperature and no oil leakage at high temperature. One is that the eccentricity is too large and the material selection of the seal is inappropriate.

The second type: seals have abnormal conditions

1. The surface of the main oil seal is hardened and the sliding surface is broken; Cause ----- Abnormal high speed working pressure.

2. The surface of the main oil seal is hardened, and the whole sealing oil seal is broken and broken; The reason is ---- hydraulic oil deterioration. The abnormal rise of oil temperature causes ozone damage to the seal and oil leakage.

3. The wear of the main oil seal surface is as smooth as mirror; The reason ---- fretting time pressure is too high stroke small.

4. Uneven wear of the mirror on the surface of the main oil seal has dissolution and swelling image; The reason ---- side pressure is too large and eccentric, and improper oil and cleaning fluid are used.

5. The sliding surface of the main oil seal has damage and abrasion marks; The reason ---- plating is poor, there is rust point matching surface rough piston rod selection of improper materials, containing impurities.

6. Rupture scar indentation at the top of the main oil seal lip; Reason ---- Improper assembly chamfering, installation, storage methods.

7. The sliding surface of the main oil seal has indentation; Reason ---- contains foreign debris.

8. There are cracks in the lip of the main oil seal; The reason is ---- improper oil, high or low working temperature, high back pressure, high speed, and too high pulse pressure frequency.

9. The main oil seal has carbonization and scorching deterioration; The reason ---- is that the residual air is compressed adiabatically.

10. The main oil seal has cracks in the heel extrusion; The reason ---- pressure is too large, extrusion clearance is too large, the supporting ring is used when, the installation groove design is not reasonable.