Rotary Shaft Seal 315x355x18 NBR SC - Single Lip Oil Seal

Rotary Shaft Seal 315x355x18 NBR SC - Single Lip Oil Seal

Rotary Shaft Seal 315x355x18 NBR SC is a large-diameter, single-lip radial shaft seal with dimensions 315x355x18 mm. Manufactured from NBR (Nitrile Butadiene Rubber), it features one spring-loaded primary sealing lip and a rubber-covered outside diameter. The single-lip design does not incorporate an additional secondary dust lip.

Technical data

315x355x18 mm dimensions

The designation 315x355x18 mm defines:

315 mm - nominal shaft diameter
355 mm - nominal housing bore diameter
18 mm - seal width

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

What does the SC design mean?

For this product, SC describes a single-lip rotary shaft seal with:

• one primary sealing lip
• a garter spring acting on the primary lip
• a rubber-covered outside diameter
• no additional secondary dust lip

The original A designation functionally corresponds to this single-lip construction.

Seal designation systems can vary between manufacturers, so the actual construction should always be checked when selecting an equivalent.

Single-lip construction

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 315x355x18 NBR SC does not have an additional secondary dust lip.

This is an important difference compared with double-lip TC designs.

NBR - Nitrile Butadiene Rubber

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

NBR is one of the most widely used elastomers in rotary shaft sealing technology and is commonly used in applications involving mineral oils and greases.

Actual compatibility depends on the specific medium and operating conditions. Temperature, shaft surface speed and environmental exposure should therefore be considered when selecting the seal.

SC vs TC rotary shaft seal

The main difference is the additional dust lip.

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

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

A 315x355x18 SC and a 315x355x18 TC can have identical nominal dimensions but different sealing constructions. They should not automatically be considered interchangeable.

SC vs B1

Both designs can be single-lip rotary shaft seals, but their outside diameter construction differs.

SC - single-lip design with a rubber-covered outside diameter.

B1 - single-lip design with a metal outside diameter.

Therefore, a B1 seal should not automatically be used as a replacement for an SC-type seal solely because the dimensions are identical.

Function of the 315x355x18 oil seal

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

The spring-loaded primary sealing lip runs against the shaft surface and helps retain a compatible lubricant or other medium within the operating area.

With dimensions of 315x355x18 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:

• Rotary Shaft Seal 315x355x18 NBR SC
• Rotary Shaft Seal 315x355x18 NBR
• Oil Seal 315x355x18 NBR
• Oil Seal 315x355x18 NBR SC
• Single Lip Oil Seal 315x355x18
• NBR Oil Seal 315x355x18
• 315x355x18 NBR A
• 315x355x18 NBR SC
• Shaft Seal 315x355x18 NBR

The recommended international product name is:

Rotary Shaft Seal 315x355x18 NBR SC - Single Lip Oil Seal

Selecting a 315x355x18 NBR SC seal

Before ordering, verify:

• shaft diameter 315 mm
• housing bore diameter 355 mm
• width 18 mm
• NBR elastomer
• single-lip construction
• spring-loaded primary sealing lip
• absence of an 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 315x355x18 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 sealing lip should be free from sharp edges, burrs and damage that could cut or prematurely wear the elastomer.

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

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

FAQ - Rotary Shaft Seal 315x355x18 NBR SC

What are the dimensions of this oil seal?

The dimensions are 315x355x18 mm: 315 mm shaft diameter, 355 mm outside diameter and 18 mm width.

Is this a single-lip rotary shaft seal?

Yes. It has one spring-loaded primary sealing lip and no additional secondary dust lip.

What material is the seal made from?

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

What does SC mean?

For this product, SC identifies a single-lip construction with a spring-loaded primary sealing lip and rubber-covered outside diameter.

Does this seal have an additional dust lip?

No. It is a single-lip design without an additional secondary dust lip.

What is the difference between SC and TC?

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

What is the difference between SC and B1?

Both can be single-lip designs. SC has a rubber-covered outside diameter, while B1 has a metal outside diameter.

Can any 315x355x18 oil seal be used as a replacement?

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

Rotary Shaft Seal 315x355x18 NBR SC - key information

Rotary Shaft Seal 315x355x18 NBR SC is a large-diameter, single-lip radial shaft seal manufactured from NBR. It measures 315x355x18 mm and features a spring-loaded primary sealing lip, rubber-covered outside diameter and no additional dust lip. The actual construction, not only the nominal dimensions, should be verified when selecting a replacement.

Available from simmering.pl, a specialist supplier of rotary shaft seals, bearings and industrial sealing solutions. Stock in Poland with worldwide shipping.