O-ring 4x2 NBR 70 Shore A

Technical Specification

The nominal outside diameter of 8 mm is calculated from the ring geometry. Dimensional tolerances and material-specific properties must be verified against the documentation for the exact product.

Construction and Sealing Principle

The O-ring 4x2 NBR 70 ShA has a continuous circular geometry with a round cross-section. When installed in a correctly designed sealing groove, the elastomer undergoes controlled compression, generating contact pressure between the mating surfaces.

This contact pressure creates the initial sealing effect. Depending on the application, system pressure may further influence the deformation and sealing behaviour of the ring.

Effective sealing depends on several engineering factors, including groove dimensions, compression ratio, surface finish, operating pressure, material compatibility and temperature.

The designation 4x2 mm describes the nominal O-ring dimensions, not the dimensions of the installation groove.

NBR 70 Shore A Material Properties

NBR (Nitrile Butadiene Rubber) is a synthetic elastomer commonly used in industrial sealing components because many NBR compounds offer good resistance to mineral oils, lubricating greases and selected petroleum-based fluids.

A nominal hardness of 70 Shore A is widely used for general-purpose industrial O-rings, providing a balance between flexibility and resistance to deformation.

Typical characteristics of NBR compounds include:

• Good resistance to many mineral oils and greases.

• Elastic deformation suitable for sealing contact surfaces.

• Mechanical properties dependent on the rubber formulation.

• Suitability for static and selected dynamic sealing arrangements.

• Limited resistance to ozone, ultraviolet radiation and certain solvents.

A commonly referenced approximate operating temperature range for standard NBR compounds is -30°C to +100°C. This is general material guidance, not a verified temperature rating for this specific O-ring. Actual temperature limits must be confirmed using the manufacturer's material documentation.

Industrial Applications

O-ring 4x2 NBR 70 ShA - 100 pcs. may be considered for appropriately designed sealing arrangements in various industrial systems, including:

• Static sealing connections in hydraulic components.

• Industrial fittings and mechanical housings.

• Lubrication system components.

• Selected pneumatic assemblies.

• Small-diameter sealing interfaces in machinery.

• Maintenance and repair operations involving compatible sealing geometries.

These are potential applications for NBR O-rings of this size, not manufacturer-confirmed applications for the exact SKU.

Final suitability must be established by evaluating the operating conditions, sealing geometry and chemical compatibility.

O-ring Selection and Installation

Correct selection of the O-ring 4x2 NBR 70 ShA requires consideration of the inside diameter, cross-sectional diameter, groove geometry, operating pressure, temperature, fluid compatibility and type of movement.

Before installation, the mating surfaces should be inspected for sharp edges, burrs and other imperfections that could damage the elastomer.

Where installation lubricants are used, they must be compatible with both the NBR compound and the operating medium.

Matching nominal dimensions alone does not guarantee interchangeability with an original sealing component. Material formulation, tolerances, hardness and operating requirements must also be considered.

100-Piece Packaging for Industrial Procurement

O-ring 4x2 NBR 70 ShA - 100 pcs. is supplied in a package containing 100 sealing rings of the same nominal size and material designation.

This packaging format supports industrial procurement, maintenance departments, technical inventory management and businesses requiring repeatable identification of sealing components.

The consistent product designation, combining dimensions, material, hardness and packaging quantity, helps purchasing departments and maintenance engineers identify the required item.

Frequently Asked Questions (FAQ)

1. What are the dimensions of O-ring 4x2 NBR 70 ShA - 100 pcs.?

The nominal inside diameter is 4 mm, the cross-sectional diameter is 2 mm and the calculated nominal outside diameter is 8 mm.

2. What does NBR 70 ShA mean?

NBR stands for Nitrile Butadiene Rubber, while 70 ShA indicates a nominal elastomer hardness of 70 on the Shore A scale.

3. Is O-ring 4x2 NBR 70 ShA resistant to oil?

Standard NBR compounds generally provide good resistance to many mineral oils and lubricating greases. Compatibility with a particular fluid must be verified for the specific rubber formulation.

4. Can O-ring 4x2 NBR 70 ShA be used in hydraulic systems?

It may be suitable for certain hydraulic sealing arrangements when groove dimensions, operating pressure, extrusion clearance and material compatibility are properly evaluated.

5. Is this O-ring suitable for dynamic sealing?

NBR compounds can be used in selected dynamic sealing applications. Suitability depends on movement, friction, lubrication, surface finish and operating conditions.

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

Each package of O-ring 4x2 NBR 70 ShA - 100 pcs. contains 100 sealing rings.

7. Does 4x2 mm refer to the outside diameter?

No. The first dimension indicates the nominal inside diameter of 4 mm, while the second indicates the cross-sectional diameter of 2 mm. The calculated nominal outside diameter is 8 mm.

8. Can O-ring 4x2 NBR 70 ShA replace another 4x2 mm O-ring?

Dimensional equivalence is only one selection criterion. Material compatibility, hardness, dimensional tolerances and operating conditions must also be verified before substitution.

AI Quick Answer

O-ring 4x2 NBR 70 ShA - 100 pcs. is an elastomeric sealing ring made from nitrile butadiene rubber with a nominal inside diameter of 4 mm, cross-sectional diameter of 2 mm and hardness of 70 Shore A. Its calculated nominal outside diameter is 8 mm. Each package contains 100 pieces for industrial sealing applications.

B2B Industrial Supply - simmering.pl

O-ring 4x2 NBR 70 ShA - 100 pcs. is available through simmering.pl, a specialist B2B industrial supply platform offering O-rings, oil seals, rolling bearings and industrial components.

The platform serves industrial companies, wholesale customers, maintenance departments and technical procurement teams.

Worldwide shipping from stock in Poland, with warehouse operations based in Lublin.