What Is a V Ring?
A V-Ring is a sealing product installed on the shaft of rotating equipment, such as a hydraulic pump, to prevent fluid leakage to the outside.
When installed on the shaft, the V-Ring is secured to the shaft by the tension generated by the elasticity of rubber, preventing not only fluid leakage but also dust and water from entering from the outside and adhering to the shaft.
V-Rings are characterized by the fact that they are available in a wide range of sizes, from small shafts of about 5 mm to large shafts of about 360 mm, so that they can be applied in units of a few millimeters.
In addition, a variety of materials can be used depending on the application, such as nitrile rubber, which has extremely high wear resistance, as well as fluorine rubber, which has excellent heat resistance.
Uses of V Rings
V-Ring seals can be used not only on bearing end faces but also on washers, bearing housings, and metal cases for oil seals.
In particular, the seal lip is flexible enough to provide sufficient sealing performance even with very low contact pressure against the sealing mating surface.
The low contact pressure (which varies depending on the width of the mounting position) can be used in a wide variety of dry running applications.
Principle of V Rings
The V-Ring is normally stretched and mounted directly on the shaft; it is held in place on the shaft by the tension created by the V-Ring’s rubber elasticity.
The V-Ring rotates with the shaft and continues to seal a stationary mating surface perpendicular to the shaft. The contact pressure at the seal lip decreases with increasing rotational speed due to centrifugal forces.
This minimizes friction losses and frictional heat, thereby significantly reducing lip wear and extending seal life.
Friction decreases gradually after static friction is exceeded and decreases rapidly in the 10-15 m/s range. Friction is then reduced to zero at high speeds (15 to 20 m/s). At this time, the V-Ring also functions as a clearance seal and deflector.
The flexible lip and hinge of the V-Ring allow it to be used in applications with a certain degree of runout, eccentricity, and angular misalignment.
Thus, the V-Ring is completely rubber-sealed, without metal or fiber reinforcement. As a result, assembly is easy.
Depending on the size, the V-Ring can also be extended to overcome flanges, pulleys, and bearing housings, allowing them to be installed without tedious and expensive disassembly.
For larger diameter sizes, V-Ring can be supplied as cut rings for on-site vulcanizing.