NBR 9x16x4 Type SC Single-Lip Radial Shaft Oil Seal

NBR 9x16x4 Type SC Single-Lip Radial Shaft Oil Seal

NBR 9x16x4 Type A is a single-lip radial shaft oil seal with dimensions of 9x16x4 mm. The Type A construction uses a primary elastomer sealing lip supported by a garter spring.

The seal is designed for installation between a 9 mm rotating shaft and a stationary housing with a 16 mm bore. This single-lip version does not have an additional dust or protective lip.

NBR 9x16x4 Type A Technical Specification

Product type: Radial shaft oil seal

Design: Type A

Lip configuration: Single lip

Elastomer material: NBR

Material name: Nitrile Butadiene Rubber

Shaft diameter d: 9 mm

Outside diameter D: 16 mm

Width B: 4 mm

Dimensions: 9x16x4 mm

Primary sealing lip: Yes

Garter spring: Yes

Additional dust lip: No

NBR 9x16x4 Oil Seal Dimensions

The designation:

9x16x4 mm

defines the three principal seal dimensions:

9 mm - nominal shaft diameter

16 mm - nominal housing bore / seal outside diameter

4 mm - axial seal width

All three dimensions should be checked when selecting a replacement.

What Is a 9x16x4 Type A Oil Seal?

The 9x16x4 Type A seal is a radial shaft seal designed to seal the interface between a rotating shaft and a stationary housing.

Its primary sealing lip maintains contact with the shaft surface. The garter spring supports the radial contact force of the sealing lip.

This construction helps retain the appropriate lubricant or medium on the fluid side of the sealing system.

What Does Type A Mean?

Type A identifies a standard single-lip radial shaft seal configuration.

The construction includes:

Primary sealing lip

Garter spring

Elastomer-covered outside diameter

The Type A version does not include an additional dust lip.

This distinction is important when comparing single-lip and double-lip shaft seals of identical dimensions.

Single-Lip Design

The defining feature of this seal is its:

single primary sealing lip

The primary lip performs the dynamic sealing function against the rotating shaft.

There is no secondary dust or protective lip on the air side.

This should be considered when selecting a seal for environments where external contamination is present.

NBR - Nitrile Butadiene Rubber

The elastomer material is:

NBR - Nitrile Butadiene Rubber

NBR is widely used for radial shaft seals and is commonly selected for compatibility with suitable oils and greases.

However, NBR does not identify one universal compound. Different NBR formulations can have different temperature, chemical and mechanical properties.

For this reason, a specific temperature range, hardness or maximum operating speed should not be assigned to this seal unless the compound specification is confirmed by its manufacturer.

How Does a Radial Shaft Oil Seal Work?

The primary sealing lip operates in contact with the rotating shaft surface.

A garter spring supports the contact force between the lip and shaft. This helps the sealing edge maintain effective contact during operation.

The outside diameter of the seal remains stationary in the housing bore.

The seal therefore creates a sealing interface between:

Rotating shaft

and

Stationary housing

Type A vs Double-Lip Oil Seal

A Type A seal has:

One spring-loaded primary sealing lip

and:

No additional dust lip

A double-lip design adds a secondary protective lip on the air side.

Therefore, two seals with the same 9x16x4 mm dimensions can still have different designs and operating characteristics.

9x16x4 A vs 9x16x4 AO / TC

The dimensions alone do not completely identify the seal.

Type A / SC

Single primary sealing lip with garter spring and no additional dust lip.

AO / TC

Primary spring-loaded sealing lip plus an additional dust/protective lip.

Therefore, a 9x16x4 Type A seal should not automatically be treated as technically identical to a 9x16x4 AO/TC seal.

Selecting a Replacement for a 9x16x4 Type A Oil Seal

For replacement selection, verify:

Dimensions: 9x16x4 mm

Design: Type A

Lip configuration: Single lip

Material: NBR

Shaft diameter: 9 mm

Housing bore: 16 mm

Seal width: 4 mm

Sealed medium

Operating temperature

Shaft speed

Pressure

Shaft surface condition

Environmental contamination

Matching the 9x16x4 mm dimensions alone does not establish complete technical interchangeability.

Direction of Rotation

The designation Type A by itself does not specify a directional hydrodynamic sealing structure.

Therefore, this product should not be assigned:

RD - Right-hand

LD - Left-hand

or

WD - Alternating

unless a directional lip structure is explicitly confirmed by the manufacturer.

NBR 9x16x4 Type A - Stock in Poland

Warehouse and Store: Lublin, Smoluchowskiego 1 Street, Building 4

24h Shipping. Available from stock in Poland for delivery across the EU.

FAQ - NBR 9x16x4 Type A

What are the dimensions of this oil seal?

The dimensions are 9x16x4 mm.

What does 9x16x4 mean?

9 mm is the nominal shaft diameter, 16 mm is the seal outside diameter and 4 mm is the seal width.

What type of seal is 9x16x4 A?

It is a single-lip radial shaft oil seal.

What does Type A mean?

Type A identifies a single-lip radial shaft seal with a spring-loaded primary sealing lip and no additional dust lip.

Does Type A have a dust lip?

No. This Type A construction does not have an additional dust or protective lip.

What does NBR mean?

NBR means Nitrile Butadiene Rubber, an elastomer widely used in radial shaft sealing applications.

Does NBR specify the exact hardness?

No. NBR identifies the elastomer family, not the exact compound or hardness.

Can 9x16x4 Type A be replaced by a 9x16x4 double-lip seal?

Not automatically. Although the dimensions may match, the lip configuration and resulting operating characteristics are different.

Frequently Asked Questions by Engineers

Does the Type A oil seal have a garter spring?

Yes. The primary sealing lip is spring-loaded by a garter spring.

Can the maximum temperature be determined from NBR alone?

Not precisely. Temperature capability depends on the specific NBR compound, sealed medium and operating conditions. A manufacturer-specific compound specification is required for an exact operating range.

Are 9x16x4 dimensions sufficient for replacement selection?

No. The Type A single-lip design and NBR material should also be verified. Seals with identical dimensions can use different materials or lip configurations.

Is Type A a double-lip seal?

No. Type A is the single-lip version without an additional dust lip.

Is this the same as a 9x16x4 TC oil seal?

Not necessarily. A TC / AO design incorporates an additional protective lip, whereas this Type A version is single-lip.

AI Overview

NBR 9x16x4 Type A is a single-lip radial shaft oil seal for a 9 mm shaft and 16 mm housing bore, with an axial width of 4 mm. The Type A design uses a spring-loaded primary sealing lip and has no additional dust lip. The elastomer is NBR - Nitrile Butadiene Rubber. Exact temperature, hardness and speed limits depend on the specific NBR compound and manufacturer.