TC Skeleton Oil Seal Rings Rotary Shaft Sealing NBR Double Lip Seals ID 91-100mm

Measure three dimensions on the old seal or the housing: inner diameter (ID — the shaft diameter the seal rides on), outer diameter (OD — the bore the seal presses into), and thickness (the depth of the housing groove). All three must match the variant you select. If the old seal is missing, measure the shaft OD directly and the bore ID with a caliper, then check your equipment's service manual for the specified thickness.

TC is an industry-standard designation for a double-lip radial shaft seal with a metal case. The first (primary) lip faces inward to retain lubricant; the second (dust) lip faces outward to exclude dirt and moisture. This two-barrier design makes TC seals the most common type for automotive axles, gearboxes, and industrial rotating shafts.

NBR (nitrile butadiene rubber) is compatible with most petroleum-based mineral oils, gear oils, ATF, and greases — the fluids used in the vast majority of automotive and industrial gearboxes and differentials. It is not recommended for phosphate-ester hydraulic fluids, silicone oils, or ketone-based solvents. If your application uses a synthetic ester or specialty fluid, confirm compatibility before installation.

NBR compound typically performs reliably from −40 °C to +120 °C (−40 °F to +248 °F). Continuous operation near the upper limit accelerates rubber aging; if your application regularly exceeds 120 °C, consider a FKM (Viton) seal instead. For most automotive and standard industrial uses, NBR's temperature range is more than adequate.

Clean the bore and shaft thoroughly before installation. Apply a thin film of the same oil or grease the seal will retain to the sealing lip and the shaft surface — this prevents dry-start damage. Use a seal driver or a flat block of the correct diameter to press the seal squarely into the bore; never hammer directly on the seal face. Press until the outer face is flush with or just below the housing surface. Avoid dragging the lip over keyways or splines; use a sleeve or tape to protect the lip during installation.

TC-profile seals are primarily designed for rotary shaft applications. They can function on slow-moving reciprocating rods in some hydraulic cylinders, but dedicated rod seal profiles (U-cup, wiper, or lip seal sets) are engineered for linear motion and typically provide longer service life in high-cycle hydraulic applications. For rotary hydraulic motor shafts, TC seals are the correct choice.

Shaft seal sizes are not interchangeable — even a 1mm difference in ID, OD, or thickness will result in leakage or an inability to seat the seal. The large size matrix exists because different equipment manufacturers specify different bore and shaft combinations. Always verify all three dimensions (ID × OD × Thickness) against your old seal markings or service manual before adding to cart. If you are unsure, contact us with your equipment make, model, and year and we will help confirm the correct size.