GRN® Rotary Shaft Seal 340x380x20 NBR TC - Double Lip Oil Seal

GRN® Rotary Shaft Seal 340x380x20 NBR TC - Double Lip Oil Seal

GRN® Rotary Shaft Seal 340x380x20 NBR TC is a large-diameter, double-lip radial shaft seal with dimensions 340x380x20 mm. Manufactured from NBR (Nitrile Butadiene Rubber), it features a spring-loaded primary sealing lip, an additional dust lip and a rubber-covered outside diameter. The TC double-lip design combines primary shaft sealing with additional protection against external contamination.

Technical data

340x380x20 mm dimensions

The designation 340x380x20 mm defines:

340 mm - nominal shaft diameter
380 mm - nominal housing bore diameter
20 mm - seal width

This is a large-diameter rotary shaft seal. When selecting a replacement, all three dimensions should be checked together with the elastomer material, lip configuration and outside diameter construction.

What does TC mean?

For this product, TC describes a double-lip rotary shaft seal construction incorporating:

• a spring-loaded primary sealing lip,
• an additional secondary dust lip,
• a rubber-covered outside diameter.

The original AO construction functionally corresponds to the commonly used international TC configuration.

Designation systems can vary between manufacturers, so the actual seal construction should always be verified when selecting an equivalent.

AO vs TC

AO is the original construction designation used for this product, while TC is a widely recognized international designation for this type of double-lip oil seal.

For international product presentation, the recommended designation is:

GRN® Rotary Shaft Seal 340x380x20 NBR TC - Double Lip Oil Seal

AO and TC should not be treated as universally identical manufacturer codes. The actual lip arrangement and outside diameter construction should be checked when selecting a replacement.

Double-lip construction

The GRN® 340x380x20 NBR TC incorporates two lips with different functions.

The primary sealing lip operates directly against the rotating shaft surface. A garter spring helps maintain contact between the sealing edge and the shaft.

The additional dust lip faces the external environment and provides an additional barrier against dust and other contaminants approaching the primary sealing area.

NBR - Nitrile Butadiene Rubber

NBR (Nitrile Butadiene Rubber) is one of the most widely used elastomers in rotary shaft sealing technology.

NBR is commonly used in sealing applications involving mineral oils and greases. Actual suitability depends on the specific medium and operating conditions.

The sealed medium, operating temperature, shaft surface speed and environmental conditions should therefore be considered when selecting an NBR oil seal.

TC vs SC rotary shaft seal

The primary difference is the presence of an additional dust lip.

TC - double-lip construction with a spring-loaded primary sealing lip and an additional dust lip.

SC - single-lip construction with a spring-loaded primary sealing lip and no additional dust lip.

A 340x380x20 TC seal and a 340x380x20 SC seal can have identical nominal dimensions but different sealing constructions. They should not automatically be considered interchangeable.

TC vs B1

These constructions differ in both lip arrangement and outside diameter design.

TC - double-lip construction with a rubber-covered outside diameter.

B1 - single-lip construction with a metal outside diameter and no additional dust lip.

Matching dimensions alone are not sufficient to establish interchangeability between these designs.

Function of the 340x380x20 oil seal

A rotary shaft seal operates between a rotating shaft and a stationary housing.

The primary sealing lip helps retain a compatible lubricant or other medium within the operating area. The additional dust lip helps reduce the ingress of external contaminants towards the primary sealing zone.

With dimensions of 340x380x20 mm, this is a large-diameter rotary shaft seal. The exact application should be confirmed using machine documentation or the dimensions and construction of the original seal.

Alternative designations and search references

This product may also be encountered under the following descriptions:

• GRN Rotary Shaft Seal 340x380x20 NBR TC
• Rotary Shaft Seal 340x380x20 NBR TC GRN
• GRN Oil Seal 340x380x20 NBR TC
• Oil Seal 340x380x20 NBR TC
• 340x380x20 NBR AO
• 340x380x20 NBR TC
• NBR Oil Seal 340x380x20
• Double Lip Oil Seal 340x380x20
• Shaft Seal 340x380x20 NBR TC

Selecting a GRN® 340x380x20 NBR TC seal

Before ordering, verify:

• shaft diameter 340 mm,
• housing bore diameter 380 mm,
• width 20 mm,
• NBR elastomer,
• AO/TC double-lip construction,
• spring-loaded primary sealing lip,
• additional dust lip,
• rubber-covered outside diameter,
• sealed medium,
• operating temperature,
• shaft surface speed,
• shaft sealing surface condition,
• requirements of the specific sealing arrangement.

Matching the 340x380x20 mm dimensions alone does not guarantee full interchangeability.

Installation

Before installation, thoroughly clean the shaft and housing bore. The shaft surface in contact with the primary sealing lip should be free from sharp edges, burrs and damage that could affect the elastomer.

The seal should be pressed evenly into the housing around its entire circumference without tilting or deformation. Uniform installation is particularly important for large-diameter rotary shaft seals.

The spring-loaded primary sealing lip should normally face the medium to be retained.

FAQ - GRN® Rotary Shaft Seal 340x380x20 NBR TC

What are the dimensions of this GRN® oil seal?

The dimensions are 340x380x20 mm: 340 mm shaft diameter, 380 mm outside diameter and 20 mm width.

Is the 340x380x20 TC a double-lip oil seal?

Yes. The TC construction features a spring-loaded primary sealing lip and an additional dust lip.

What material is the seal made from?

The sealing element is manufactured from NBR (Nitrile Butadiene Rubber).

What does TC mean on an oil seal?

For this product, TC identifies a double-lip construction with a spring-loaded primary sealing lip, an additional dust lip and a rubber-covered outside diameter.

What does AO mean?

AO is the original construction designation for this product. Its functional configuration corresponds to the commonly used TC double-lip design.

What is the purpose of the additional dust lip?

It provides an additional barrier that helps reduce the ingress of dust and other external contaminants towards the primary sealing area.

What is the difference between TC and SC?

TC is a double-lip design with an additional dust lip. SC is a single-lip design without an additional dust lip.

Can any 340x380x20 oil seal be used as a replacement?

No. Dimensions, elastomer, lip configuration, outside diameter construction and operating requirements should all be verified.

GRN® Rotary Shaft Seal 340x380x20 NBR TC - key information

GRN® Rotary Shaft Seal 340x380x20 NBR TC is a large-diameter, double-lip radial shaft seal manufactured from NBR. It measures 340x380x20 mm and features a spring-loaded primary sealing lip, an additional dust lip and a rubber-covered outside diameter. The TC configuration provides primary shaft sealing together with additional protection against external contamination.

GRN® rotary shaft seals have been part of the TG Ersatzteile Polska product range since 2007. Available from simmering.pl, a specialist supplier of rotary shaft seals, bearings and industrial sealing solutions. Stock in Poland with worldwide shipping.