What is a V-ring?

A V-ring is a fully elastomeric seal that is mounted over a rotating shaft. The ring consists of an elastic body that clamps around the shaft and a flexible sealing lip. This lip does not run radially over the shaft, but seals axially against a stationary counterface.

The counterface may, for example, be part of a bearing housing, cover, flange or another stationary construction. In this way, the V-ring forms a protective barrier between the environment and the underlying bearing or sealing arrangement.

Protection of bearings and seals

The main function of a V-ring is to help keep out dust, dirt, mud, splash water and other contaminants. A V-ring can therefore be installed in front of a bearing or another primary seal to provide additional protection.

How does a V-ring work?

The V-ring is mounted on the shaft and clamps around it through its elasticity. As a result, the complete V-ring rotates with the shaft. The flexible sealing lip remains in contact with the stationary counterface.

When stationary, the sealing lip is pressed lightly against the counterface with a small amount of preload. During rotation, a slinger effect is also created, helping to throw dirt and moisture away from the sealing area.

Sealing at higher circumferential speeds

As the circumferential speed increases, centrifugal force influences the contact between the sealing lip and the counterface. At very high speeds, the lip may partially lift away from the surface. The V-ring then increasingly works through its slinger effect and as a gap seal. The permitted speed depends on factors including the type, size, material and application.

Difference between a V-ring and an oil seal

A V-ring and an oil seal are both used with rotating shafts, but they have a different construction and function. A V-ring rotates with the shaft, while its sealing lip makes axial contact with a stationary counterface.

A traditional radial oil seal, on the other hand, is usually mounted in a housing and seals radially against the rotating shaft. Oil seals are used, among other purposes, to retain lubricants inside a system.

V-ring as additional protection

A V-ring can be installed in front of another seal and function as a pre-seal. The V-ring helps keep dirt and splash water away from the underlying seal. A V-ring and oil seal can therefore perform different functions within the same sealing arrangement.

Different types of V-rings

V-rings are available in different profiles and designs. The correct type depends on factors such as the shaft diameter, available installation space, circumferential speed and operating conditions.

VA V-ring

The VA V-ring is a widely used standard version for general applications. This profile offers a practical combination of stability, sealing performance and easy installation.

VS V-ring

The VS V-ring has a more compact profile and can be used when less installation space is available.

VL V-ring

The VL V-ring has a slim profile and is used, among other applications, where limited axial installation space is available.

VE V-ring

The VE V-ring is intended for larger shaft diameters and heavier industrial applications. Its more robust profile can be suitable for machines exposed to heavier contamination and demanding operating conditions.

Materials for V-rings

The material of a V-ring largely determines its resistance to temperature, oil, water, chemicals, ozone and other environmental influences. The material must therefore be matched to the operating conditions and medium.

NBR V-rings

NBR is a commonly used material for V-rings. It offers good resistance to many mineral oils and greases and has good mechanical properties. This makes NBR suitable for many general industrial applications.

FKM / Viton V-rings

FKM/FPM, often referred to by the brand name Viton®, is used when higher temperature or chemical resistance is required. FKM is resistant to many oils, fuels and chemicals, although suitability should always be checked for the specific medium.

EPDM V-rings

EPDM performs well with water, weathering, ozone and UV. However, the material is not suitable for many mineral oils and greases. Always check whether the material is compatible with the medium that comes into contact with the V-ring.

Applications of V-rings

V-rings are used on rotating shafts that need to be protected against dirt, dust, splash water and other contaminants. Thanks to their simple construction, V-rings can be used in a wide range of machines and industrial installations.

Pumps and motors

In pumps, motors and electric motors, a V-ring can be used to protect the transition between a rotating shaft and the housing against contamination.

Bearings and bearing housings

A V-ring can be installed in front of a bearing or bearing housing to keep dirt and moisture away from the bearing area. This provides additional protection for the bearing arrangement.

Industrial machinery

V-rings are also used in various industrial and mechanical installations, including machines exposed to dust, mud, water or other external contamination.

Which V-ring do I need?

When selecting the correct V-ring, the shaft diameter is an important starting point. After installation, the V-ring must clamp sufficiently around the shaft without placing unnecessary strain on the elastomer.

Next, the V-ring profile, available installation space, counterface and circumferential speed should be assessed. Conditions around the seal, such as dirt, moisture and mechanical loading, also play an important role.

Finally, the material, temperature and medium must be matched to each other. Techniparts can help select a suitable V-ring based on the available technical information.

View and order V-rings

Looking for a suitable V-ring or V-seal? View the available types, dimensions and materials in our V-ring webshop. Here you will find various VA, VE, VL and VS V-rings.