V-Ring Seal
Also known as: V-ring · Forsheda V-ring · flinger seal · axial lip seal
A V-ring is a one-piece axial shaft seal with a V-shaped cross-section that mounts on the shaft (not the housing) and deflects a flexible lip radially against a mating face — sealing without a housing bore.
Technical Detail
V-rings (trade name Forsheda from SKF) are unique in that they mount directly on the shaft and rotate with it, while the flexible lip seals against a fixed mating surface (housing face, bearing race, or shaft collar) by axial lip deflection of 0.7–2.5 mm. This makes them ideal for installations where machining a housing bore for a TC oil seal is impractical. Construction: single-piece NBR or FKM elastomer; lip angle 20°–45°. Size range: shaft diameters 8–600 mm. Temperature: NBR –40°C to +100°C; FKM –20°C to +180°C. Applications: agricultural machinery axles (where mud and water ingress is the concern, not oil retention), conveyor drive shafts, electric motor bearing covers, and as supplementary external seals in front of TC oil seals. Shaft surface finish Ra ≤ 3.2 µm (no specific hardness requirement unlike TC oil seals). Installation: stretch V-ring over shaft, position so lip contacts mating surface with correct axial preload per manufacturer chart.
Reference Standards
- ISO 6194-3 (V-rings)
- DIN 3761
Related Terms
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- Dynamic vs Static Seal — A static seal prevents leakage between non-moving surfaces (flange faces, port plugs); a dynamic sea…
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