Fail

                           Reason

         Precaution

      Remarks

Normal performance, but oil leaks at   low pressure

When sealing, if the shaft diameter is   small, the interference between the lip of the Y-shaped sealing ring and the   shaft is too small

When the hole is sealed, its lip and   the hole match the interference is too small

There is dust or foreign matter   between the sealing lip and the mating sealing surface

Maintain sufficient surplus;

Carefully wash, remove dust and   foreign matter, and keep it clean

Serious damage to the lips

Too much interference between the lip   and the contacting sealing surface

Relative speed is too high

The roughness of the sealing surface   in contact with the lip is too large

The surface of the hole or shaft is   scratched or the coating is peeling off

There is foreign matter or dust or   particles between the lips and the contact surface

Choose the appropriate amount of   interference

Adapt to the right speed

Choose the right roughness

Repair scratches

Carefully wash and keep clean

Cracked or scratched lips

Scratched or cracked or chipped lips

Check carefully during installation,   and fill in qualified parts if inappropriate

Gap bite

Too much gap

Low material hardness

Fluid working pressure is too high

Choose the right gap

Choose a harder material plus   retaining ring

Use Y-ring corresponding to fluid   pressure

Damaged Y-ring root

The amount of interference is too   large, resulting in greater friction and dry friction

The surface roughness in contact with   it is too large

Choose the appropriate amount of   interference and try to ensure lubrication

Choose suitable surface roughness,   generally Ra0.2～0.4μm is   more appropriate

Consider strict inspection before   assembly when designing

The Y-shaped seal is twisted or turned   over, causing leakage

The frictional torque of relative   movement is greater than the torsion resistance of the Y-shaped seal

Try to reduce friction

Improve Y-ring material hardness

Add a support ring to prevent the   Y-ring from twisting and rolling

Back pressure damages the Y-shaped   sealing ring and causes leakage

Because the Y-shaped sealing ring is a   one-way seal, if it is two-way sealed, it will be installed back, which may   cause back pressure damage under high pressure.

Additional guide support ring (between   the roots of the Y-shaped seal ring)

Release pressure tank pressure release