O-ring 14x2.5 NBR 70 Shore A

Technical Specifications - O-ring 14x2.5 NBR 70 Shore A

The nominal outside diameter of 19 mm is calculated from the inside diameter of 14 mm plus twice the cross-sectional diameter of 2.5 mm.

This is a nominal geometric value, not an individually measured dimension.

What Does O-ring 14x2.5 NBR 70 Shore A Mean?

14 mm - Inside Diameter

The value 14 mm indicates the nominal inside diameter of the O-ring in its uninstalled condition.

This dimension is important when selecting a seal for a specific shaft, bore or sealing groove.

The O-ring inside diameter should not automatically be treated as the exact diameter of the mating component.

Correct selection depends on the sealing arrangement, groove geometry and required elastomer deformation.

2.5 mm - Cross-Sectional Diameter

The value 2.5 mm represents the nominal diameter of the circular elastomer cross-section.

Cross-sectional diameter influences the required groove dimensions, sealing compression and groove fill.

Using an O-ring with an incorrect cross-section may result in leakage, excessive deformation or premature seal damage.

NBR - Nitrile Butadiene Rubber

NBR stands for Nitrile Butadiene Rubber, a synthetic elastomer widely used in industrial sealing technology.

NBR generally provides good resistance to many mineral oils, lubricating greases and selected hydraulic fluids.

Its actual chemical compatibility depends on the rubber compound, operating temperature, fluid composition and exposure duration.

NBR should not be considered universally resistant to all chemicals.

Certain solvents, specific fuel formulations and glycol-based brake fluids may be incompatible with standard NBR compounds.

70 Shore A - Rubber Hardness

The designation 70 Shore A indicates the nominal hardness of the elastomer according to the Shore A hardness scale.

Hardness affects the deformation characteristics of the seal, its contact pressure and its behavior under mechanical loading.

NBR 70 Shore A is commonly used in static industrial sealing applications.

However, hardness alone does not determine the maximum permissible operating pressure.

Pressure capability also depends on groove geometry, extrusion gap, temperature and operating conditions.

Construction and Operating Principle

The O-ring 14x2.5 NBR 70 Shore A is a one-piece, continuous elastomeric sealing ring with a circular cross-section.

It does not contain a metal housing, spring-loaded sealing lip or separate mechanical components.

Sealing is achieved through controlled elastic deformation between mating surfaces.

Static Sealing

In static applications, the O-ring is installed in a correctly dimensioned sealing groove.

When the components are assembled, the elastomer is compressed between the mating surfaces, creating a sealing barrier that limits fluid or gas leakage.

Typical static sealing arrangements include housing covers, flanges, hydraulic components and mechanical connections.

The groove must provide suitable compression and sufficient space for the elastomer under operating conditions.

Dynamic Sealing

O-rings may also be used in certain dynamic applications, including appropriately designed reciprocating sealing systems.

However, dynamic operation requires additional consideration of friction, lubrication, movement speed, pressure and wear.

The dimensions 14x2.5 mm and hardness 70 Shore A do not independently establish suitability for a particular dynamic application.

Chemical Resistance of NBR 70 Shore A

Nitrile rubber is frequently selected for sealing systems involving mineral oil-based lubricants.

These characteristics describe the general NBR material family and are not test results for this specific batch of O-rings.

For unusual operating fluids, chemical compatibility should be confirmed using the technical data for the particular elastomer compound.

O-ring 14x2.5 NBR 70 Shore A vs Other Variants

NBR 70 Shore A vs NBR 90 Shore A

Both versions may have identical nominal dimensions but different elastomer hardness.

NBR 70 Shore A is generally more deformable than NBR 90 Shore A.

NBR 90 Shore A may be selected for appropriately designed sealing arrangements requiring greater resistance to extrusion into a clearance gap.

However, a higher hardness rating does not automatically guarantee a higher permissible operating pressure.

Changing hardness requires verification of groove geometry, compression and operating conditions.

NBR vs FKM (FPM)

NBR and FKM O-rings may share the same nominal dimensions while offering different thermal, chemical and mechanical characteristics.

FKM is often selected for applications requiring greater resistance to elevated temperatures or specific chemicals.

NBR remains widely used for sealing systems operating with compatible mineral oils and lubricating greases.

These elastomers should not be considered automatically interchangeable.

NBR vs EPDM

EPDM is commonly used in many water-based systems and applications involving compatible glycol-based fluids.

Standard EPDM is generally unsuitable for contact with mineral oils.

Replacing an NBR O-ring with an EPDM version requires careful verification of chemical compatibility.

Selection and Interchangeability

Before purchasing an O-ring 14x2.5 NBR 70 Shore A, verify the following:

1. Nominal inside diameter of 14 mm.

2. Cross-sectional diameter of 2.5 mm.

3. NBR elastomer material.

4. Nominal hardness of 70 Shore A.

5. Type and composition of the sealing medium.

6. Operating temperature.

7. System pressure and extrusion clearance.

8. Sealing groove dimensions and geometry.

9. Static or dynamic operating conditions.

10. Required dimensional tolerances and applicable standards.

Identical nominal dimensions do not necessarily guarantee full interchangeability.

O-rings measuring 14x2.5 mm may differ in material, hardness, dimensional tolerances and chemical resistance.

For critical applications, the exact material specification and any required industry approvals should also be verified.

Typical Applications of NBR 70 Shore A O-rings

NBR O-rings with a nominal hardness of 70 Shore A are commonly used in appropriately designed sealing arrangements involving:

• Hydraulic system components.

• Mechanical housings and covers.

• Threaded connections with dedicated sealing grooves.

• Hydraulic manifolds and valve blocks.

• Lubrication systems.

• Selected pumps and valves.

• Flanged connections and housing assemblies.

These are general application categories for NBR elastomeric seals.

They do not establish that the specific 14x2.5 mm size is suitable for every machine, valve or hydraulic component within these categories.

Installation and Operating Recommendations

Preparation Before Installation

Before installation, inspect and clean the sealing groove and mating surfaces.

Remove dirt, metal particles, burrs and other contaminants that could damage the elastomer.

Check the groove dimensions and ensure that the O-ring is suitable for the intended sealing arrangement.

Correct Installation

During installation:

1. Avoid excessive stretching of the O-ring.

2. Prevent twisting or rolling of the seal inside the groove.

3. Protect the elastomer when passing over sharp edges or threads.

4. Use only assembly lubricants compatible with NBR and the operating medium.

5. Ensure that the O-ring is positioned correctly in the sealing groove.

6. Apply the required compression according to the sealing system design.

Incorrect installation may cause leakage, localized wear or premature elastomer damage.

Storage

Store O-rings in a clean, dry environment, preferably in their original protective packaging.

Protect the elastomer from ultraviolet radiation, ozone, excessive heat and unnecessary mechanical deformation.

Appropriate storage conditions help preserve the physical properties of rubber sealing components.

FAQ - O-ring 14x2.5 NBR 70 Shore A

1. What are the dimensions of the O-ring 14x2.5 NBR 70 Shore A?

The nominal inside diameter is 14 mm and the cross-sectional diameter is 2.5 mm. The calculated nominal outside diameter is 19 mm.

2. What does NBR mean in an O-ring designation?

NBR stands for Nitrile Butadiene Rubber. It is a synthetic elastomer commonly used in technical sealing applications, particularly those involving compatible mineral oils and lubricants.

3. What does 70 Shore A mean?

70 Shore A indicates the nominal hardness of the rubber compound on the Shore A scale. This property influences the seal's deformation behavior and contact pressure.

4. Is the O-ring 14x2.5 NBR 70 Shore A oil-resistant?

NBR generally offers good resistance to many mineral oils and lubricating greases. Compatibility with a particular oil depends on its chemical composition, operating temperature and the specific rubber compound.

5. Can an NBR 70 Shore A O-ring be replaced with an FKM O-ring?

Not automatically. FKM has different chemical, thermal and mechanical properties. The replacement must be checked for compatibility with the operating medium and sealing arrangement.

6. Will an O-ring with a 14 mm inside diameter fit a 14 mm groove?

Not necessarily. Correct groove selection depends on the sealing configuration, groove geometry and required compression. The nominal inside diameter alone is insufficient to determine compatibility.

7. Can an NBR 70 Shore A O-ring operate under high pressure?

Pressure capability depends on the sealing arrangement, extrusion gap, operating temperature and possible use of backup rings. The 70 Shore A hardness designation alone does not define a maximum operating pressure.

8. How many O-rings are included in one package?

Each package contains 100 pieces of O-ring 14x2.5 mm NBR 70 Shore A.

O-ring 14x2.5 NBR 70 Shore A - Key Technical Information

O-ring 14x2.5 NBR 70 Shore A is an elastomeric sealing ring with a 14 mm inside diameter, 2.5 mm cross-section and 19 mm nominal outside diameter. Manufactured from nitrile rubber with a nominal hardness of 70 Shore A, it is suitable for appropriately designed sealing applications involving compatible mineral oils and lubricants. Each package contains 100 pieces.

The O-ring 14x2.5 NBR 70 Shore A is available from simmering.pl, a specialist supplier of industrial sealing components, radial shaft seals and rolling bearings.

With warehouse operations in Lublin, Poland, simmering.pl supplies industrial maintenance departments, engineering companies, manufacturers and international B2B customers.

Products are shipped from stock in Poland, with delivery options throughout Europe and worldwide.