V-ring shaft seals utilize centrifugal slinger action to provide effective protection against dry and wet contamination. In combination with an SKF metal-cased radial seal, the V-ring reduces wear and extends the service life of the oil seal and bearings. The V-ring also performs well in dry running applications. Because it is all rubber and very elastic, it can be stretched over flanges or other components for easy installation with minimal unit disassembly. It has very low torque drag and heat build up, and does not require expensive countersurface preparation.
V-ring seals are unique all-rubber seals for rotary shafts. They are made entirely of rubber material and comprise a body and a conical shaped sealing lip, which is joined to the body by means of a resilient “hinge”.V-rings are mounted on and rotate with the shaft. The lip seals axially against a counter face, which is perpendicular to the shaft. The body has an interference fit on the shaft and holds the lip in position. V-rings can be stretched out and fitted over a flange during installation, which is a very valuable characteristic, especially in the case of repair. They can operate at sliding velocities up to 8 m/s. At velocities above 8 up to 12 m/s the V-rings need to be axially located.
V-ring seals are available in a large variety of designs and sizes to fit the requirements of most applications. V-rings are normally made of nitrile rubber. For applications where higher temperatures occur or where aggressive media are present, V-rings made of fluoro rubber should be used.
A unique sealing concept
The V-ring is an all-rubber seal available from All Seals.It is mounted directly on the shaft by hand and seals against a counterface. This unique design has been extensively used on a broad range of applications.
Designed with a long, flexible lip, the V-ring can act as a face seal, a lip seal or slinger. The construction is three part: the body (a), the conical self-adjusting lip (b) and the hinge (c). The elastic body holds itself in place on the rotating shaft while dynamic sealing takes place where the lip is in axial contact with the counterface. The counterface should be metal and can be the end of a gearbox housing, a washer, a suitable steel stamping, even the back of an oil seal. Generally no seal bore is required and no shaft preparation is needed.
In addition to highly effective contaminant exclusion, Vrings can be used to retain grease lubricants. However, with proper countersurface preparation they can run dry with very low torque loss and good service life. Because the V-ring is very elastic (smaller V-rings can be stretched up to 2 1/2 times their free diameter) it can often be easily fitted to shafts without disassembly of the unit—even over flanges, pillow blocks, or other assemblies. One size V-ring can be used on a number of shaft sizes either English or metric dimension. Less than 142 sizes covers a wide range of shaft sizes from .110" (2.7mm) to 29' (9000mm). Sizes up to 79.530" (2020mm) and beyond are available in nitrile or fluoroelastomer (Viton®) covering a wide variety of media compatibility in temperature ranges from -40°F to 212°F (nitrile) and -15°F to 392°F fluoroelastomer.
In addition, special constructions and sizes can be made to order including split versions.
Note: Beyond the six primary V-ring styles and rubber compounds, options are available for special installation dimensions and operating conditions (ie. confined spaces, exposure to caustic fluids). Many V-ring profiles can be ordered for shaft diameters beyond 78.740" (2000mm). Contact All Seals for details.
There are six styles of V-rings.
VR1 The most common style available in the widest range of sizes from .110" (2.7mm) shaft to 79.530" (2020mm) nitrile and fluoroelastomer. Ideal for protecting gearboxes, electric motors and drives.
VR2 The original V-ring designed with a wide body and tapered heel to firmly hold the ring on the shaft. Available in sizes from .180" (4.5mm) shaft to 8.270" (210mm). Commonly used in agricultural and automotive applications.
VR3 Very compact axial cross-section commonly used in confined spaces to replace labyrinth seals. Available in nitrile and fluoroelastomer for shaft sizes from 4.134" (105mm) shaft to 78.745" (2000mm) and beyond.
VR4 A heavy-duty large diameter style commonly used in rolling mills as a secondary seal for heavy duty applications where the primary seal has to be protected against water and or particulate contamination. VR4 is the preferred heavy duty V-ring in replacement applications. Selected sizes are in stock and others can be made to order. For new designs, the VR6 should be considered and has similar mounting dimensions. Available in both nitrile and fluoroelastomer for shafts from 11.811" (300mm) to over 78" (2000mm).
VR5 A heavy-duty large diameter style designed to operate in the severe conditions found in metals and paper mills. The unique body profile can accommodate radial and axial support in high shaft speeds applications. It has an extension that can be fitted into mechanical components or trimmed to length to meet existing space requirements (contact SKF for details). Available for shaft diameters from 11.811" (300mm) to over 78" (2000mm) in nitrile and fluoroelastomer on a made-toorder basis.
VR6 This heavy-duty profile is also designed primarily for protecting high speed bearing arrangements in rolling mills, papermaking and large machine applications. It should especially be considered for new equipment designs. The shape is similar to the VR5 except it does not have the extension to the rear of the body section, allowing a narrower B1. It does retain the saddle feature for axial and radial location on the shaft with a specially designed clamping band. The key installation dimensions are the same as the VR4 except for the body height. Available on a made to order basis in both nitrile and fluoroelastomer for shafts from 11.811" (300mm) to over 78" (2000mm).
Contact All Seals for specific size and installation data.
V-rings are normally made of nitrile rubber that features good chemical resistance, resistance to wear and can be used in applications with normal operating temperatures. For applications with higher temperatures or where aggressive media are present, V-rings made of fluoro rubber can be supplied. The permissible operating conditions for V-rings made of nitrile or fluoro rubber are listed in the table. In the product table under the heading "Lip code", the letters R and V are used to identify nitrile rubber and fluoro rubber respectively.