V-rings can be used with both oil and grease lubrication
The seal's elastic rubber ring sits securely on the shaft and rotates with it, while the seal lip exerts slight axial pressure on the stationary part
Depending on the material, V-rings can be used at operating temperatures of 40 and +150 °C
They are easy to fit and allow relatively high shaft misalignments at low speeds
A surface roughness Ra of 2 to 3 mm is sufficient for the sealing surface
At peripheral speeds above 8 m/s, the Vring must be axially secured to the shaft
At speeds above 12 m/s, the ring must be prevented from floating above the shaft, e.g. by means of a steel plate support ring
At peripheral speeds above 15 m/s, the sealing lip will detach from the surface, so that the V-ring effectively becomes a gap seal
The good sealing performance of the V-ring is mainly determined by the fact that the ring itself acts as a pendulum disc that ejects contaminants and fluids
This is why the seal is usually placed on the outside of the housing in the case of grease lubrication, and on the inside of the housing in the case of oil lubrication
When a V-ring is used as a secondary seal, it protects the primary seal from excess contaminants and moisture