TC Skeleton Oil Seals ID 5-9mm FKM Rubber Dual Lip Rotary Shaft Seal Ring

Measure the shaft diameter (ID), the bore diameter (OD), and the housing depth (thickness) with calipers. The seal must match all three dimensions. For example, an 8mm shaft in a 16mm bore with a 5mm housing depth requires an 8*16*5mm seal — that's approximately 0.315" × 0.630" × 0.197". When in doubt, go by the shaft diameter first, then confirm OD and thickness against your housing.

TC designates a double-lip (dual-lip) seal with a metal skeleton reinforcement ring. The primary lip retains oil or grease; the secondary dust lip faces outward to block contaminants. This two-barrier design is generally preferred over single-lip SC seals in applications where both fluid retention and contamination exclusion matter.

Yes. FKM (Viton®-type) rubber typically withstands continuous temperatures up to around 200 °C (392 °F) and resists petroleum oils, hydraulic fluids, fuels, and many solvents far better than standard NBR rubber. It is generally the preferred choice for high-heat or chemically aggressive environments such as engine compartments, hydraulic systems, and industrial gearboxes.

FKM rubber offers good resistance to weathering, ozone, and moisture, making these seals suitable for outdoor machinery in most cases. The metal skeleton provides structural rigidity. For fully submerged or salt-spray applications, confirm the specific shaft speed and pressure conditions with your equipment manual before installation.

TC-type skeleton oil seals in this size range typically support rotary shaft surface speeds up to around 4–8 m/s, depending on shaft finish, lubrication, and operating temperature. A smooth shaft finish (generally Ra ≤ 0.8 µm) and adequate lubrication at the lip are important for achieving rated service life. Consult your equipment specifications to confirm compatibility.

These are metric-dimensioned seals (ID × OD × Thickness in mm), conforming to general ISO/DIN metric shaft seal standards. They are not inch-standard seals. Verify your housing bore and shaft are metric before ordering. If you only have inch measurements, multiply by 25.4 to convert to mm — for example, a 5/16" shaft is approximately 7.94mm, so an 8mm ID seal would typically be the correct fit.

You choose your pack quantity at checkout: 1, 2, 5, 10, or 20 pieces per order. For a single repair, 1 or 2 PCS is sufficient. For fleet maintenance or workshop stock, 10 or 20 PCS offers a lower per-piece cost. If you are rebuilding multiple units of the same equipment, ordering 5 PCS or more is generally more economical.

Clean the bore and shaft thoroughly. Lightly lubricate the seal lip with the fluid it will retain (oil or grease). Press the seal squarely into the bore using a flat driver or dedicated seal installation tool — never hammer directly on the seal face or lip. The primary lip should face the fluid side (inward). Avoid nicking the lip on keyways, splines, or sharp shaft edges during installation; use a tapered installation sleeve if available.