NBR O-Rings 5x2 mm 70 Shore A

AI Overview

NBR O-Rings 5x2 mm with a hardness of 70 Shore A are elastomer sealing rings intended for series production, maintenance and industrial repair work. Each O-Ring has an inside diameter of 5 mm and a cross-section of 2 mm. NBR is commonly used with mineral oils, lubricating greases and many hydraulic fluids. The package contains 1000 identical seals, making it suitable for machine manufacturers, production facilities, hydraulic and pneumatic service companies, maintenance departments and B2B customers requiring a regular supply of one specific size.

What Makes This Product Different

This version is intended for high-volume use and repeatable industrial applications. A package of 1000 pieces reduces purchasing frequency, simplifies stock management and supports continuous use of the same O-Ring size in production, assembly or maintenance.

The 5x2 mm designation means:

• Inside Diameter: 5 mm
• Cross Section: 2 mm

The approximate outside diameter of the uncompressed O-Ring is 9 mm. The product should not be selected by outside diameter alone. Correct identification requires verification of the inside diameter, cross-section, material and hardness.

A hardness of 70 Shore A is widely used in technical sealing applications. It provides a practical balance between elasticity, controlled compression and resistance to permanent deformation in a correctly designed groove.

Construction and Operating Principle

An O-Ring is a closed elastomer ring with a circular cross-section. When placed in a properly designed groove, it is compressed between two mating surfaces.

This deformation creates sealing contact that closes the clearance and limits the movement of the operating medium. In pressurised systems, hydraulic oil, compressed air or another compatible fluid may additionally force the elastomer against the sealing surfaces.

O-Rings can be used in static joints and in selected dynamic applications. In moving systems, sealing performance depends more strongly on surface finish, lubrication, speed, operating pressure and groove geometry.

If the extrusion gap is too large or the system pressure is excessive, the rubber may be forced out of the groove. In such conditions, a suitable back-up ring or a different hardness may be required.

Material Properties

NBR, also known as Nitrile Butadiene Rubber, is one of the most common elastomers used in hydraulic systems, pneumatic equipment and general mechanical engineering.

The material provides:

• good resistance to mineral oils,
• resistance to many lubricating greases,
• good abrasion resistance,
• suitable mechanical strength,
• stable sealing properties in many industrial applications,
• suitability for static and selected dynamic sealing arrangements.

A typical operating temperature range for standard NBR compounds is approximately -30°C to +100°C. Actual operating limits depend on the compound formulation, fluid type, pressure, exposure time and type of movement.

NBR should not be treated as a universal sealing material. It is generally not the preferred choice for prolonged exposure to ozone, intense UV radiation, hot steam, glycol-based brake fluids or certain aggressive chemicals.

Typical Industrial Applications

O-Rings measuring 5x2 mm are used in compact sealing assemblies where a small inside diameter and repeatable cross-section are required.

Typical applications include:

• hydraulic valves,
• compact manifolds,
• oil fittings,
• technical plugs and connectors,
• quick couplings,
• pressure regulators,
• pneumatic systems,
• small pumps,
• lubrication equipment,
• technical valves,
• automation components,
• production machinery,
• assembly kits,
• series-manufactured equipment.

Suitability should always be confirmed according to the groove dimensions, operating fluid, pressure, temperature and type of movement.

Typical Failure Symptoms

The O-Ring should be replaced if any of the following are observed:

• oil leakage,
• grease leakage,
• compressed air loss,
• pressure drop,
• permanent flattening,
• surface cracking,
• material hardening,
• excessive stretching,
• installation cuts,
• one-sided abrasion,
• elastomer swelling,
• extrusion into the clearance gap.

Repeated failure in the same groove may indicate incorrect groove geometry, sharp edges, excessive clearance, poor lubrication or material incompatibility with the operating medium.

Recommended During Installation

Before installation:

• confirm the 5x2 mm size,
• clean the sealing groove,
• remove all remains of the old seal,
• inspect the groove for burrs,
• protect the O-Ring from sharp threads and edges,
• use an installation lubricant compatible with NBR,
• avoid unnecessary stretching,
• prevent twisting,
• do not use sharp tools,
• verify correct seating before closing the assembly.

In series production, storage and dispensing procedures should prevent contamination, mixing with other sizes and permanent deformation.

Technical Specification

Manufacturer: GRN

Product Type: O-Ring

Size: 5x2 mm

Inside Diameter: 5 mm

Cross Section: 2 mm

Approximate Outside Diameter: 9 mm

Material: NBR

Full Material Name: Nitrile Butadiene Rubber

Hardness: 70 Shore A

Colour: Black

Cross Section Shape: Round

Typical Temperature Range: Approximately -30°C to +100°C, depending on compound and operating conditions

Typical Media: Mineral oils, lubricating greases and selected technical fluids compatible with NBR

Application: Static sealing and selected dynamic systems

Sales Unit: 1000 pieces

Groove Selection

Correct O-Ring selection requires verification of both the 5x2 mm dimensions and the groove geometry.

The following parameters should be checked:

• groove diameter,
• groove width and depth,
• compression ratio,
• permitted stretch,
• operating pressure,
• extrusion gap,
• operating temperature,
• fluid compatibility,
• surface finish,
• type of movement.

Insufficient compression may cause leakage. Excessive compression increases friction, accelerates permanent deformation and may reduce service life.

Related Components

Depending on the system design, the O-Ring may be used together with:

• back-up rings,
• guide rings,
• piston seals,
• rod seals,
• rotary shaft seals,
• X-rings,
• flat gaskets,
• sealing washers,
• assembly sleeves,
• hydraulic oil,
• assembly lubricant.

Why B2B Customers Choose the 1000-Piece Pack

The bulk package is intended for companies that regularly use one specific O-Ring size. It allows the product to be stocked near a production line, in a maintenance warehouse or in a service workshop.

The O-Rings can be used as:

• maintenance stock,
• series production components,
• repair kit elements,
• machine assembly parts,
• workshop consumables,
• production continuity stock,
• technical warehouse inventory.

A 1000-piece package reduces order frequency and supports standardisation of one sealing size across multiple machines or products.

Professional Industrial Supply

The product is intended for:

• machine manufacturers,
• production facilities,
• maintenance departments,
• hydraulic service companies,
• pneumatic workshops,
• valve manufacturers,
• equipment assembly companies,
• repair kit manufacturers,
• sealing distributors,
• wholesale B2B customers.

Popular Searches

• NBR O-Ring 5x2 1000 pcs
• O-Rings 5x2 mm wholesale
• O-Ring 5x2 70 Shore A
• NBR O-Rings 70 ShA 1000 pieces
• rubber seal 5x2 mm
• hydraulic O-Ring 5x2
• NBR sealing ring 5x2
• black O-Ring 5x2
• O-Rings for series production
• industrial O-Rings 5x2 bulk pack

FAQ

Does 5x2 mean a 5 mm inside diameter?

Yes. The first value is the 5 mm inside diameter and the second value is the 2 mm cross-section. The approximate outside diameter is 9 mm.

Can 5x2 NBR O-Rings be used with hydraulic oil?

NBR is commonly used with mineral oils and many standard hydraulic fluids. Compatibility with the exact fluid should still be confirmed before series use.

Does the package contain only one size?

Yes. All 1000 O-Rings in the package have the same 5x2 mm size, NBR material and 70 Shore A hardness.

Can an O-Ring be reused after dismantling?

Reuse is not recommended. The seal may have permanent deformation, small cuts or stretching that can reduce sealing performance after reassembly.

How should 1000 O-Rings be stored?

They should be stored in a dry, cool and shaded place, away from ozone, heat sources, UV radiation, unidentified oils and sharp objects.