TC Oil Seal NBR Double Lip Skeleton Seal for Rotation Shaft — ID 8–35mm

Measure your shaft's inner diameter (ID), the bore's outer diameter (OD), and the housing depth (height). Match all three dimensions to the variant listed as ID × OD × Height. For example, a 20 × 35 × 7mm seal fits a 20mm (≈3/4") shaft in a 35mm (≈1-3/8") bore with a 7mm (≈9/32") housing depth. When in doubt, the shaft ID must be an exact match — the OD can typically tolerate ±0.1mm for a proper press fit.

TC designates a double-lip seal with a metal skeleton (FB) reinforcement. The primary lip retains lubricant while the secondary dust lip generally prevents contaminants from entering the housing. This is the most common configuration for rotating shaft applications in automotive, agricultural, and industrial equipment.

NBR (nitrile rubber) seals typically handle temperatures from approximately -40°F to +250°F (-40°C to +120°C). For higher-temperature environments — such as exhaust-adjacent or turbo applications — a Viton (FKM) seal is generally recommended instead.

Yes. NBR is well-suited for petroleum-based oils, mineral hydraulic fluids, and greases — the most common fluids in automotive and industrial rotating shaft applications. It is generally not recommended for use with ketones, esters, or highly aromatic fuels. If your application uses synthetic ester-based fluids, verify compatibility before installation.

The double-lip design provides a secondary barrier against water and dust ingress, making these seals suitable for moderately wet or dirty environments — such as agricultural equipment, outdoor power tools, and marine auxiliary shafts. For fully submerged or high-pressure water-jet applications, additional sealing measures are generally recommended.

A shaft surface roughness of Ra 0.2–0.8 µm (approximately 8–32 µin) is typically recommended for rotating lip seals. Shafts that are too smooth can cause the lip to hydroplane and leak; shafts that are too rough accelerate lip wear. Always lightly lubricate the seal lip with clean oil before installation, and inspect the shaft for grooves or corrosion that could cause premature failure.

Standard TC lip seals are designed for low-pressure applications — typically up to about 7 psi (0.5 bar) of internal pressure. They are not suitable for high-pressure hydraulic circuits. For higher-pressure systems, a pressure-rated or spring-energized seal is generally required.

Use a flat seal driver or a socket slightly smaller than the OD to press the seal squarely into the bore. Never hammer directly on the seal face or lip. Ensure the bore is clean and free of burrs. Apply a thin film of clean oil to the seal lip and a light smear of grease or sealant to the outer OD if the bore is aluminum or has a rough finish. Press until the seal face is flush with or just below the housing surface.