SC Oil Seals - Durus

What Is a SC Oil Seal?

The SC type combines Type C case (full rubber coat) with the S-style lip configuration (single primary sealing lip with garter spring) plus an auxiliary dust lip on the outboard side. The rubber-coated OD seals against soft or variable housings, while the single primary lip generates less friction than a double-lip TC. The added dust lip provides contamination exclusion without the friction of full double-lip construction.

Construction summary:
Case Type: C (full rubber coat)
Lip Configuration: S-style single lip with dust lip

When to Choose SC

• Soft housings (aluminum, plastic) with potential dust exposure
• High-speed shafts where lower friction is desired while still excluding dust
• Applications where TC seals generate too much heat at speed
• Hydraulic motor or pump applications with mixed clean/dirty exposure

When NOT to Choose SC

• Hard precision-bored housings where the rubber coat is unnecessary (use SB or SB2 instead)
• Heavy dust environments where full double-lip TC or TB2 provides more robust exclusion
• Low-cost applications where TC's standard construction is the cheaper choice

Related Seal Types

Frequently Asked Questions

What is an SC oil seal?

SC is a Durus designation for a Type C case (full rubber outer coating) combined with the S-style single lip configuration plus an auxiliary dust lip. The rubber-coated OD accommodates soft or variable housings; the single primary sealing lip with garter spring retains lubricant; the dust lip excludes contamination. SC provides a middle option between low-friction single-lip SB (no dust lip) and double-lip TC (more friction, more exclusion).

What is the difference between SC and TC oil seals?

Both share the same Type C rubber-coated case construction. The difference is in the lip design. TC has a Standard double lip with primary sealing lip plus auxiliary dust lip. SC has an S-style single primary sealing lip plus an auxiliary dust lip - essentially the same dust exclusion as TC but with the simpler S-style primary lip design. SC generates slightly less friction than TC at higher speeds while still providing dust exclusion.

When should I use SC instead of SB?

Choose SC when the housing is soft material (aluminum, plastic) or has marginal bore tolerance - the rubber-coated OD of the Type C case accommodates these conditions where the bare-metal case of SB would not seal reliably. Both SB and SC use the same S-style single sealing lip with dust lip. The decision is housing-driven: hard precision housings → SB, soft or variable housings → SC.

Are SC oil seals appropriate for high-speed shafts?

SC is a reasonable choice for moderate-to-high speed shafts where TC generates excessive friction and heat. The S-style single lip design with garter spring provides lower friction than TC's double-lip construction while still maintaining sealing performance. For very high-speed applications (above 3000 RPM with specific shaft size and configuration), confirm the maximum shaft speed against Durus catalog limits for the specific compound and size - call (888) 203-2358 for engineering guidance on high-speed applications.