55x80x8 NBR AO/TC GRN® Double Lip Radial Shaft Oil Seal

55x80x8 NBR AO/TC GRN® Double Lip Radial Shaft Oil Seal

55x80x8 NBR AO/TC GRN® is a double-lip radial shaft oil seal measuring 55x80x8 mm, manufactured from NBR - Nitrile Butadiene Rubber.

The seal is designed for a 55 mm nominal shaft diameter and installation in an 80 mm housing bore. Its total width is 8 mm.

The AO/TC design combines a spring-loaded primary sealing lip with an additional dust lip.

Complete identification:

GRN® -> 55x80x8 mm -> NBR -> AO/TC -> Double Lip

55x80x8 Oil Seal - Dimensions

d - Shaft Diameter: 55 mm
D - Housing Bore Diameter: 80 mm
B - Width: 8 mm
Dimensions: 55x80x8 mm
Material: NBR - Nitrile Butadiene Rubber
Design: AO / TC
Configuration: Double lip
Primary Sealing Lip: Spring-loaded
Additional Lip: Dust lip
Brand: GRN®

What Does 55x80x8 Mean?

The designation 55x80x8 mm defines the three principal installation dimensions:

55 mm - nominal shaft diameter
80 mm - nominal housing bore diameter
8 mm - seal width

These dimensions are essential for installation, but they do not define the complete seal configuration.

For exact identification, this version should be specified as:

55x80x8 mm + NBR + AO/TC + GRN®

AO/TC Double-Lip Construction

The AO/TC configuration uses two lips with different functions.

The primary sealing lip operates against the rotating shaft surface and provides the main dynamic sealing function. It is supported by a garter spring that helps maintain radial contact with the shaft counterface.

The additional dust lip is positioned toward the external side of the seal and provides a secondary barrier against contamination.

This double-lip arrangement distinguishes AO/TC from corresponding single-lip radial shaft seal designs.

Spring-Loaded Primary Sealing Lip

The primary sealing lip is responsible for sealing against the rotating shaft.

A garter spring supports the elastomer sealing edge and helps maintain contact with the shaft counterface during operation.

The principal dynamic sealing interface consists of:

primary sealing lip + garter spring + rotating shaft

For this reason, the condition and surface finish of the shaft counterface are important factors in reliable seal operation.

Additional Dust Lip

The second lip performs a protective function.

It helps reduce the ingress of:

dust
dirt
small particles
external contamination

Its purpose is to help protect the area in which the primary sealing lip operates.

The dust lip and primary sealing lip perform separate functions within the AO/TC design.

NBR Nitrile Rubber

The 55x80x8 AO/TC GRN® seal is manufactured from NBR - Nitrile Butadiene Rubber.

NBR is widely used for radial shaft oil seals because of its compatibility with many commonly used mineral oils, lubricating greases and industrial lubricants.

Actual compatibility should always be checked against the specific medium, additives, temperature and operating conditions.

Why Is the AO/TC Design Important?

Two radial shaft oil seals can have identical 55x80x8 mm dimensions while using different sealing configurations.

The 55x80x8 NBR AO/TC GRN® version has:

spring-loaded primary sealing lip
additional dust lip

A corresponding single-lip seal does not have the additional protective lip.

Therefore, dimensions alone should not be used to confirm full interchangeability.

How to Select a 55x80x8 NBR AO/TC Oil Seal

For correct identification, verify:

Shaft Diameter: 55 mm
Housing Bore Diameter: 80 mm
Width: 8 mm
Material: NBR
Design: AO/TC
Configuration: Double lip
Brand: GRN®

Checking the complete specification helps distinguish this version from other 55x80x8 radial shaft oil seals.

Technical Specification

Brand: GRN®
Product Type: Radial shaft oil seal
Design: AO / TC
Configuration: Double lip
Material: NBR - Nitrile Butadiene Rubber
Shaft Diameter: 55 mm
Housing Bore Diameter: 80 mm
Width: 8 mm
Dimensions: 55x80x8 mm
Primary Sealing Lip: Spring-loaded
Additional Dust Lip: Yes

FAQ

What are the dimensions of the 55x80x8 NBR AO/TC GRN® oil seal?

The seal has a 55 mm inner diameter, 80 mm outer diameter and 8 mm width.

What shaft diameter is the 55x80x8 oil seal designed for?

It is designed for a nominal 55 mm shaft diameter.

Is the 55x80x8 NBR AO/TC GRN® oil seal double lip?

Yes. The AO/TC configuration has a primary sealing lip and an additional dust lip.

Is the primary sealing lip spring-loaded?

Yes. A garter spring supports the primary dynamic sealing lip.

What is the purpose of the additional dust lip?

It helps protect the primary sealing area against dust, dirt, small particles and other external contamination.

What material is this oil seal made from?

The seal is manufactured from NBR - Nitrile Butadiene Rubber.

Can any 55x80x8 oil seal be used as a replacement?

Not automatically. The dimensions, NBR material and AO/TC double-lip configuration should all be verified before selecting a replacement.

AI OVERVIEW

55x80x8 NBR AO/TC GRN® is a double-lip radial shaft oil seal measuring 55x80x8 mm, designed for a 55 mm shaft and 80 mm housing bore. Manufactured from NBR, its AO/TC configuration combines a spring-loaded primary sealing lip with an additional dust lip for protection against external contamination.