Oil Seal SB - Rotary Shaft Seal

What is an Oil Seal SB?

The SB oil seal is a rotary shaft seal which consists of a steel outer shell. The elastomer sealing lip together with the internal steel garter spring reinforces radial pressure on the rotating shaft. This design makes the rotary shaft seal extremely reliable and stable during operations while keeping friction and heat generation low. Its steel outer diameter guarantees a stable press-fit, avoiding rotation or axial displacement during service. Sealing performance can be enhanced by pairing the SB type rotor seal with RB axial seals or V-rings, especially in dirty or splash-heavy environments. Due to it’s simple yet durable design, the oil seal SB is used a lot in a variety of mechanical systems requiring a reliable sealing. Other profiles, such as the SC oil seal or the TC oil seal, offer a rubber outer diameter or a dual-lip sealing. The oil seal SB on the other side focusses mainly on maximum structural rigidity and a clean dynamic sealing.

Applications

Material Options for SB Oil Seals

Automotive systems that experience elevated temperatures but still rely on oil compatibility often benefit from ACM, this is a material which is optimized for long-term performance in hot oil environments. On the other hand, VMQ (Silicone) is selected flexibility across extreme low or high temperatures is needed, though this material is less suited for heavy mechanical loads. And at last, there is EPDM. This material is used in applications involving coolants, steam or water-based media, situations where oil is not the primary fluid being sealed.

To ensure that your oil seal SB type delivers a reliable sealing, longer service life and a reduced wear on both the lip and the shaft, it’s very important to choose the right material. 

Material table

Below you’ll find a table providing information about the most common compounds used for oil seals SB and their typical operating ranges.

Performance & Installation Guidance

To ensure a long and reliable service life of your SB oil seals, the shaft surface must be smooth. It must have a smooth surface (Ra 0.2-0.8 µm), be hardened to at least 45HRC and free from spiral machining marks that could cause oil pumping outward. The housing should meet H8 tolerances and have a clean, lightly roughened finish to support stable press-fitting of the metal outer diameter. Before you install the rotary shaft seal, you must first apply a thin layer of lubricant to the sealing lip to prevent dry start-up. It's best to use a flat pressing tool that contacts only the outer case, allowing the SB oil seal to enter the bore evenly without deformation. The spring side should always face towards the lubricant.

Cross-Reference: Alternative Names for SB Oil Seals

A lot of manufacturers use different naming systems for their equivalent of the SB oil seals. This table helps identify matching profiles across brands.

FAQ - SB Oil Seals