GRN NBR Oil Seal 40x67x8 AO/TC - Double Lip Radial Shaft Seal

GRN NBR Oil Seal 40x67x8 AO/TC - Double Lip Radial Shaft Seal

GRN NBR Oil Seal 40x67x8 AO/TC is a double lip radial shaft seal made from NBR nitrile rubber. Its nominal dimensions are 40x67x8 mm: 40 mm shaft diameter, 67 mm outside diameter and 8 mm width. The AO/TC design incorporates a primary sealing lip and an additional dust lip that helps protect the main sealing area against external contamination.

Technical data

The exact elastomer hardness, operating temperature range, maximum shaft speed and permissible pressure are not stated because these parameters have not been confirmed for the exact GRN 40x67x8 NBR AO/TC version.

What does GRN 40x67x8 NBR AO/TC mean?

GRN - brand of the radial shaft seal.

40x67x8 mm - nominal dimensions of the oil seal.

40 mm - nominal shaft diameter.

67 mm - nominal outside diameter of the seal.

8 mm - nominal seal width.

NBR - nitrile rubber used as the elastomeric sealing material.

AO/TC - designation associated with a double lip radial shaft seal construction incorporating a primary sealing lip and an additional dust lip.

Seal type codes are not completely standardised across all manufacturers. When comparing GRN with another brand, the actual seal construction should therefore be checked rather than relying solely on the AO or TC code.

GRN 40x67x8 oil seal dimensions

Radial shaft seal dimensions are normally expressed as:

d x D x B

For this product:

40x67x8 mm

where:

• d = 40 mm - nominal shaft diameter

• D = 67 mm - nominal outside diameter

• B = 8 mm - nominal seal width

All three dimensions should correspond to the requirements of the sealing arrangement.

Matching only the 40 mm shaft diameter is not sufficient for correct oil seal identification.

AO/TC double lip construction

GRN 40x67x8 NBR AO/TC uses a double lip radial shaft seal design.

Functionally, the construction incorporates:

• a primary sealing lip operating against the shaft surface

• an additional dust lip facing the external environment

• an elastomeric sealing element made from NBR

The primary lip performs the main shaft sealing function.

The additional dust lip provides a secondary barrier that helps reduce the ingress of dust, dirt and other external contaminants into the area around the primary sealing lip.

Primary sealing lip vs dust lip

The two lips perform different functions.

Primary sealing lip - operates against the rotating shaft and provides the principal sealing function.

Additional dust lip - helps protect the primary sealing area against contaminants originating from the surrounding environment.

The dust lip does not replace the primary sealing lip. It provides an additional level of protection on the external side of the seal.

NBR nitrile rubber

NBR, or nitrile rubber, is one of the most widely used elastomer families for radial shaft seals.

Appropriately selected NBR compounds are commonly used in sealing arrangements involving many mineral oils and greases.

However, the actual performance depends on the specific NBR compound and operating conditions.

The NBR designation alone does not define:

• exact elastomer hardness

• exact operating temperature range

• maximum shaft speed

• permissible pressure

• compatibility with every fluid

• specific approvals or certifications

Where any of these parameters are critical, they should be verified for the exact seal version.

GRN 40x67x8 AO/TC vs single lip oil seal

The principal difference is the presence of the additional dust lip.

GRN 40x67x8 AO/TC incorporates:

• primary sealing lip

• additional dust lip

A conventional single lip radial shaft seal does not have this additional protective lip.

However, a double lip seal should not automatically be substituted for every single lip 40x67x8 mm seal.

The sealing arrangement, lubrication conditions, shaft surface and contamination protection requirements should be considered before replacement.

NBR 40x67x8 vs FKM 40x67x8

NBR and FKM radial shaft seals can have exactly the same 40x67x8 mm nominal dimensions while being manufactured from different elastomer families.

NBR - nitrile rubber.

FKM/FPM - fluoroelastomer.

The material difference affects properties such as fluid compatibility and behaviour under different temperature conditions.

For this reason, an FKM 40x67x8 seal should not automatically be considered a direct replacement for an NBR 40x67x8 seal solely because the dimensions match.

Alternative designations and search references

This product may also be searched as:

• GRN 40x67x8 NBR AO

• GRN 40x67x8 NBR TC

• GRN 40x67x8 NBR AO/TC

• GRN Oil Seal 40x67x8

• NBR Oil Seal 40x67x8

• Oil Seal 40x67x8 NBR

• Oil Seal 40x67x8 AO

• Oil Seal 40x67x8 TC

• TC Oil Seal 40x67x8

• Double Lip Oil Seal 40x67x8

• Radial Shaft Seal 40x67x8

• NBR Radial Shaft Seal 40x67x8

• Shaft Seal 40x67x8 NBR

• Simmerring 40x67x8 NBR

OEM and cross-reference numbers are not provided unless specifically confirmed for this product.

How to select a 40x67x8 oil seal

Before selecting a replacement, verify:

• 40 mm shaft diameter

• 67 mm housing bore / seal outside diameter

• 8 mm width

• NBR elastomer

• required double lip construction

• AO/TC type

• sealed medium

• operating temperature

• shaft speed

• lubrication conditions

• shaft running surface condition

• external contamination conditions

Matching the 40x67x8 mm dimensions alone does not guarantee complete interchangeability.

Radial shaft seals with identical dimensions may differ in elastomer material, sealing lip geometry, outside surface design and operating characteristics.

Applications

GRN 40x67x8 NBR AO/TC is a radial shaft seal designed for a nominal 40 mm shaft and a nominal 67 mm housing bore.

The double lip construction is suitable for sealing arrangements where the primary shaft sealing function is supplemented by an additional barrier against external contamination.

The designation GRN 40x67x8 NBR AO/TC alone does not confirm compatibility with a specific:

• electric motor

• geared motor

• gearbox

• pump

• vehicle

• machine

• industrial equipment

without appropriate technical documentation or a confirmed reference number.

Installation of GRN 40x67x8

Before installation, thoroughly clean the shaft, housing bore and mating surfaces.

Check:

• shaft running surface condition

• absence of sharp edges and burrs

• correct installation direction

• cleanliness of the housing bore

• even insertion of the seal

• protection of the sealing lip during installation over the shaft

Installation force should not be applied in a way that could deform the seal body or damage the sealing lips.

If an assembly lubricant is used, its compatibility with NBR and the sealed medium should be verified.

FAQ

What are the dimensions of the GRN 40x67x8 oil seal?

The nominal dimensions are 40x67x8 mm: 40 mm shaft diameter, 67 mm outside diameter and 8 mm width.

Is GRN 40x67x8 a double lip oil seal?

Yes. The AO/TC version incorporates a primary sealing lip and an additional dust lip.

What does NBR mean?

NBR stands for nitrile rubber, an elastomer widely used in radial shaft seals and other industrial sealing components.

What does TC mean on an oil seal?

TC is commonly used for a radial shaft seal construction with a primary sealing lip and an additional dust lip. Because type codes can vary between manufacturers, the actual seal design should also be verified.

What does AO mean?

AO is also encountered as a designation for double lip radial shaft seal designs. Manufacturer nomenclature may differ, so actual construction should be compared when selecting an alternative.

What is the purpose of the additional dust lip?

The additional lip helps reduce the ingress of external contaminants into the area around the primary sealing lip.

Can an NBR 40x67x8 oil seal be replaced with FKM 40x67x8?

Not automatically. Although the nominal dimensions are identical, NBR and FKM are different elastomer families. Fluid compatibility, temperature and other operating conditions should be checked.

Are all 40x67x8 oil seals the same?

No. Seals with identical dimensions can differ in elastomer material, lip construction and technical characteristics. Dimensions are only one part of correct seal identification.

GRN NBR Oil Seal 40x67x8 AO/TC - key information

GRN NBR Oil Seal 40x67x8 AO/TC is a double lip radial shaft seal for a 40 mm shaft, with a 67 mm outside diameter and 8 mm width. It uses NBR nitrile rubber and an AO/TC construction with a primary sealing lip and an additional dust lip that helps protect the sealing area against external contamination.

GRN NBR Oil Seal 40x67x8 AO/TC is available from the specialist industrial supplier simmering.pl, with stock in Poland and worldwide shipping. Assistance with radial shaft seal identification and technical selection is also available.