TC Oil Seal NBR Double Lip Rotary Shaft Seal 5mm Thick — ID 8–40mm OD 17–70mm

Measure three dimensions: the shaft diameter (this becomes your ID), the bore housing diameter (this becomes your OD), and the housing depth (this must be ≥5mm for all seals in this listing). The seal ID should match the shaft diameter closely — typically within 0.1–0.3mm for a proper dynamic seal. For example, a 20mm shaft generally takes a 20mm ID seal. All seals here are 5mm (≈3/16") thick, so confirm your housing can accommodate that depth before ordering.

TC stands for a double-lip seal configuration. The inner (primary) lip contacts the rotating shaft to retain lubricant inside the housing. The outer (secondary) lip faces the environment and acts as a dust/dirt excluder. This dual-lip design generally outperforms single-lip (SC) seals in applications where both oil retention and contamination exclusion are needed — such as gearboxes, pumps, and agricultural axles.

TC-type lip seals are designed for low-pressure dynamic sealing applications — typically up to approximately 0.05 MPa (≈7 psi) of differential pressure. They are not intended for high-pressure hydraulic circuits. If your application involves significant internal pressure, contact us to confirm suitability or consider a different seal type.

NBR rubber generally performs well in wet environments and resists water, petroleum oils, and grease effectively. The secondary dust lip on the TC design also helps exclude mud and debris. However, NBR is not recommended for prolonged exposure to ozone, direct UV sunlight, or ketone/ester-based fluids. For extreme outdoor UV exposure, a Viton (FKM) seal may be a better long-term choice.

Yes. All dimensions follow metric standards and are generally compatible with ISO 6194 and DIN 3760 shaft seal specifications. If your equipment uses inch-based dimensions, convert carefully before ordering — for reference, 20mm ≈ 0.787", 25mm ≈ 0.984", and 40mm ≈ 1.575". When in doubt, measure your existing seal directly with calipers rather than relying solely on equipment documentation.

NBR TC oil seals are generally rated for shaft surface speeds up to approximately 4–6 m/s, depending on lubrication conditions and operating temperature. As a rough reference, a 20mm shaft at 1,500 RPM produces a surface speed of about 1.6 m/s — well within range. For higher-speed applications, ensure the lip contact area is adequately lubricated to prevent premature wear and heat buildup.

Use a seal driver or flat press tool sized to the OD of the seal and press it squarely into the bore — never strike the seal face directly with a hammer. Before installation, lightly coat the seal lip with clean grease or the lubricant being sealed. Make sure the shaft end has a chamfer or smooth lead-in to avoid cutting the lip during assembly. Install with the primary lip facing inward (toward the lubricant source).