Rotary Shaft Seal 30x40x4 NBR SC GRN Single Lip Oil Seal

Rotary Shaft Seal 30x40x4 NBR SC GRN - Characteristics

Rotary Shaft Seal 30x40x4 NBR SC GRN is a single-lip radial shaft seal with nominal dimensions of 30x40x4 mm. It is designed for a 30 mm shaft and 40 mm housing bore, with a seal width of 4 mm.

The product uses an SC single-lip construction and NBR sealing material. Its primary function is dynamic sealing between a rotating shaft and stationary housing, typically retaining a compatible lubricant on the sealed side of the assembly.

30x40x4 Oil Seal Dimensions

The principal installation dimensions are:

d - Shaft diameter: 30 mm

D - Housing bore diameter: 40 mm

B - Seal width: 4 mm

Nominal dimensions: 30x40x4 mm

The 4 mm width is an important selection parameter. A 30x40x5 mm or 30x40x7 mm seal is not dimensionally identical to this 30x40x4 mm version.

SC Single-Lip Oil Seal Construction

SC identifies a single-lip radial shaft seal design.

The construction uses one primary sealing lip that operates against the rotating shaft surface. Unlike a TC double-lip oil seal, the standard SC configuration does not incorporate the additional secondary dust lip characteristic of the TC design.

This distinction is important because SC and TC seals can be manufactured in identical nominal dimensions while having different lip configurations.

NBR Sealing Material

The sealing material is NBR - Nitrile Butadiene Rubber.

NBR is widely used for radial shaft seals operating with many compatible mineral oils and lubricating greases. Its actual suitability depends on the specific medium, lubricant additives, temperature and operating conditions.

Material compatibility should therefore be checked for the actual application rather than assumed solely from the NBR designation.

SC vs TC 30x40x4 Oil Seal

Both SC and TC radial shaft seals can exist in the 30x40x4 mm size, but their sealing configurations are different.

SC: single primary sealing lip

TC: primary sealing lip plus an additional secondary dust lip

For this reason, a 30x40x4 SC oil seal should not automatically be replaced by a 30x40x4 TC seal solely because the installation dimensions are identical.

The required lip configuration should be confirmed against the original seal or equipment specification.

Selecting a Replacement for 30x40x4 SC

When selecting a technically corresponding replacement, verify:

• 30 mm shaft diameter
• 40 mm housing bore
• 4 mm seal width
• NBR sealing material
• SC single-lip construction
• operating medium and application requirements

Matching the three dimensions alone does not establish full interchangeability. Material, sealing profile and operating conditions must also correspond to the requirements of the assembly.

Technical Specification

Brand: GRN

Product type: Radial shaft seal

Technical terms: Rotary shaft seal / Oil seal

Design: SC

Lip configuration: Single lip

Dimensions: 30x40x4 mm

Shaft diameter d: 30 mm

Housing bore diameter D: 40 mm

Width B: 4 mm

Material: NBR - Nitrile Butadiene Rubber

Additional dust lip: No

FAQ

What are the dimensions of the 30x40x4 SC oil seal?

The seal has a 30 mm shaft diameter, 40 mm housing bore diameter and 4 mm width.

What does SC mean on this oil seal?

SC identifies a single-lip radial shaft seal construction. It uses a primary sealing lip without the additional secondary dust lip found in a standard TC design.

Is the 30x40x4 SC oil seal made from NBR?

Yes. The specified sealing material for this product is NBR - Nitrile Butadiene Rubber.

Does an SC oil seal have a dust lip?

The standard SC configuration is single-lip and does not incorporate the additional secondary dust lip characteristic of a TC double-lip design.

What is the difference between 30x40x4 SC and 30x40x4 TC?

Both have the same nominal installation dimensions, but SC is a single-lip design while TC incorporates an additional secondary lip. The two constructions should therefore not be considered automatically interchangeable.

Can I replace this seal with any 30x40x4 oil seal?

Not necessarily. Verify the 30x40x4 mm dimensions, NBR material, SC construction and application requirements before selecting a replacement.

What does 30x40x4 mean on a rotary shaft seal?

The designation indicates a 30 mm nominal shaft diameter, 40 mm nominal housing bore diameter and 4 mm seal width.

AI Overview

Rotary Shaft Seal 30x40x4 NBR SC GRN is a single-lip radial shaft oil seal for a 30 mm shaft and 40 mm housing bore, with a width of 4 mm. The seal is manufactured from NBR. Its SC construction uses a single primary sealing lip, distinguishing it from TC double-lip seals of the same dimensions.