Ø50-120mm TC Skeleton Oil Seal Ring FKM Rubber Double Lip Seals for Rotary Shaft

Measure three dimensions: the shaft outer diameter (this becomes the seal's ID), the housing bore inner diameter (this becomes the seal's OD), and the housing groove depth (this becomes the seal's Height/Width). Match all three to the variant listed as ID × OD × Height. If your shaft is 60mm, your housing bore is 80mm, and your groove is 10mm deep, select the 60 × 80 × 10mm variant.

NBR (nitrile) seals are adequate for standard mineral oils at moderate temperatures (typically up to ~100 °C). FKM (fluoroelastomer) is the better choice when operating temperatures exceed 120 °C, when synthetic lubricants such as PAO or ester-based fluids are used, or when the environment involves fuel, hydraulic fluid, or chemical exposure. FKM maintains its elasticity and sealing force across a wider temperature range, reducing the risk of lip hardening and bypass leakage.

"TC" is a standardized seal type code indicating a double-lip seal with a metal case (skeleton frame). The first lip is the primary sealing lip that contacts the rotating shaft to retain lubricant. The second lip is a dust exclusion lip that faces the external environment to block contaminants. This two-barrier design makes TC seals the most common choice for general rotary shaft applications.

TC seals are designed for dynamic shaft sealing in lubricated environments, not for full submersion under sustained water pressure. The secondary dust lip provides moderate water splash resistance. For applications with continuous water ingress or pressure differentials, a dedicated water-resistant seal or additional labyrinth protection is recommended. Contact us to confirm suitability for your specific conditions.

Clean the housing bore and lightly lubricate the outer case with a compatible oil or grease before pressing in. Use a flat-faced seal driver or a piece of flat bar stock that contacts the outer metal case evenly — never strike the rubber lip directly. Press the seal in squarely until the outer face is flush with or just below the housing face. Lightly coat the sealing lip with the lubricant it will be retaining before fitting over the shaft to prevent dry-start wear.

A shaft surface roughness of Ra 0.2–0.4 µm (approximately 8–16 µin) is the standard recommendation for TC lip seals. Too smooth (below Ra 0.2 µm) can prevent the lip from forming a hydrodynamic oil film, causing dry running. Too rough (above Ra 0.5 µm) accelerates lip wear. The shaft should also be free of spiral machining marks, which can pump lubricant past the seal lip over time.

Yes. FKM rubber has broad compatibility with synthetic gear oils (PAO-based), automatic transmission fluids (ATF), and most hydraulic fluids. It is also resistant to many ester-based and polyglycol lubricants. If you are using an unusual or proprietary fluid, contact us with the fluid specification and we can advise on compatibility before you order.