VA FKM

Composition, construction and operation of the A10 (Viton)

At very high circumferential speeds, the lip can (partly) experience “lift-off” (often mentioned around 15–20 m/s, depending on size, compound and conditions) and the V-ring increasingly acts as a gap seal and flinger disc. The sealing effect is therefore a combination of contact between the lip and the counterface and the flinging action caused by rotation, which actively throws water and contamination away from the sealing zone.

Applications and why the Viton A10 is so suitable for them

The V-ring A10 is widely used as a protective seal in situations where the outside of the machine is exposed to dirt, dust, mud, condensation or splash water. Think of electric motors, pumps and drives where bearings need to remain protected, but also gearboxes and general machinery where grease retention and contamination protection come together. The Viton A10 becomes especially relevant where these conditions combine with higher operating temperatures, hot surrounding components, or contact with oils, fuels or more chemically demanding media. In agricultural, construction and transport applications, the A10 is popular because it places low demands on shaft and housing machining, is relatively tolerant of minor coaxiality deviations or eccentricity, and is easy to install without a complex housing. This typically translates directly into less contamination in the bearing arrangement, a longer service life of the radial seal behind it, and less maintenance because both the V-ring and the primary seal generally last longer.

Material focus: Viton (FKM/FPM)

In the market, the A10 is commonly available in NBR and FKM, and in some cases also in EPDM (or other compounds) on request. This page focuses specifically on the Viton option, which is typically chosen when temperatures are higher or when you’re dealing with more chemically aggressive media than standard rubber compounds can comfortably handle. In many applications, FPM is valued for its aging resistance under heat and its broad resistance to oils, fuels and many chemicals, which helps the lip and retaining section stay stable over time. The trade-off is that this material family can be less flexible at low temperatures, and it is usually a more expensive choice than NBR. In practice, the selection logic is straightforward: if heat, oil/fuel exposure or chemical influence is a key driver, a Viton A10 is often the more reliable long-term option.

FKM properties

Comparison: A10 (VA) vs other V-ring profiles

The V-ring A10 (VA) is the most common standard profile and is known for its straight back and compact axial design, making it a solid all-round choice for general contamination protection and grease retention. If you need an even tighter grip on the shaft, the S10 V-ring (VS) profile is often preferred: it uses a conically extended retaining section, which helps it sit more securely in certain installations. When installation space is limited, the L10 V-ring (VL) profile is used because it has a smaller, more compact cross-section, designed specifically for tight axial spaces while keeping the same basic sealing principle. For very large shafts or heavier-duty conditions, the E10 V-ring (VE) can be relevant, as this one is typically selected for larger diameters and more demanding environments.

How do you choose the right Viton V-ring A10?

You determine the sizing of a V-ring A10 primarily based on the shaft diameter, because the ring grips the shaft through its own preload. So you choose the A10 that matches your nominal shaft size, not based on the outer diameter. Next, you look at the installation conditions: the shaft must be free of burrs, and a small chamfer helps prevent tearing or damage during installation. The counterface is at least as important, because the lip seals axially against it; the surface must be clean, flat and reasonably smooth, because deep scratches or burrs reduce service life and make the sealing action unstable.

If you expect higher circumferential speeds or a lot of vibration, it is advisable to provide an axial stop or retention so the ring cannot “creep” along the shaft. You then select the compound based on temperature (continuous and peak), medium (oil/grease, fuels, chemicals) and environment (outdoor, UV/ozone, abrasive contamination). In terms of standards and tolerances: V-rings are forgiving, but they are still molded rubber products with production tolerances. Therefore, design practically with sufficient margin, and focus mainly on the correct size on the shaft, a suitable counterface, and an elastomer choice that matches your operating conditions, where FKM/FPM is typically the step up when heat and media demand it.

Cross reference

In summary, the V-Ring A10 is a versatile rotary seal that provides effective shaft sealing by keeping out contaminants and preventing leakage. Its versatile application possibilities, low friction, high circumferential speeds, insensitivity to alignment, long lifespan, and ease of assembly make it a reliable choice for various industries and machinery types. Choose the V-Ring A10 for optimal shaft sealing performance and protection.

If you would like more information, of if you do not know which Ring you should have, feel free to contact us. 

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