1. The quality of the rubber o-ring is unqualified.

2. The rubber o-ring is seriously aging.

3. The installation of the rubber o-ring is unqualified.

4. The formula of the rubber o-ring is unqualified.

5. The sealing design of mechanical equipment is unqualified.

6. There are problems with the groove size and quality of mechanical equipment.

7. The oil temperature is too high, causing the rubber o-ring to be worn, aged or even failed.

8. The pressure is too high, causing the o-ring to be squeezed out.

9. Inadequate lubrication, or use of solid lubrication, causes the rubber o-ring to be worn.

10. The medium and oil have impurities and are contaminated, causing the rubber o-ring to wear or be corroded.