O-Ring NBR 25.3x2.4 mm 70 ShA

O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs) is an industrial bulk package containing 1000 GRN elastomer sealing rings. Each O-ring has a nominal 25.3 mm inside diameter and 2.4 mm circular cross-section and is manufactured from NBR nitrile rubber with a nominal hardness of 70 Shore A. The resulting nominal outside diameter is 30.1 mm.

O-Ring NBR 25.3x2.4 mm 70 ShA - Product Identification

The complete specification of this bulk variant is:

Size: 25.3x2.4 mm
Material: NBR
Hardness: 70 ShA / 70 Shore A
Brand: GRN
Quantity: 1000 pcs

An O-ring is a closed elastomer sealing element with a circular cross-section. Its sealing function is generated through controlled compression of the elastomer between mating surfaces.

For correct identification and replacement, the complete combination 25.3x2.4 mm + NBR + 70 ShA should be considered rather than dimensions alone.

O-Ring NBR 25.3x2.4 mm Dimensions

The dimensional designation 25.3x2.4 mm means:

d1 - Inside Diameter: 25.3 mm
d2 - Cross-Section Diameter: 2.4 mm

The nominal outside diameter is calculated as:

25.3 mm + 2 x 2.4 mm = 30.1 mm

Therefore:

Inside Diameter d1: 25.3 mm
Cross-Section d2: 2.4 mm
Nominal Outside Diameter: 30.1 mm

For an O-ring, the first dimension specifies the inside diameter, while the second specifies the diameter of the circular cross-section.

NBR - Nitrile Butadiene Rubber

NBR (Nitrile Butadiene Rubber) is one of the most widely used elastomers for technical sealing components.

NBR is commonly selected for compatibility with many mineral oils, mineral greases and mineral-oil-based hydraulic fluids. This makes nitrile rubber suitable for consideration in a broad range of mechanical, hydraulic and pneumatic sealing systems.

NBR is not universally resistant to every fluid or chemical. Suitability should therefore be evaluated against the actual operating medium, temperature, exposure duration and service conditions.

70 Shore A Hardness

The designation 70 ShA specifies a nominal elastomer hardness of 70 Shore A.

Hardness influences how the O-ring deforms during installation and behaves when compressed within the sealing groove.

The value 70 ShA is not a pressure rating. Permissible operating pressure depends on the complete sealing arrangement, including groove geometry, extrusion gap, operating medium, temperature and service conditions.

How Does O-Ring 25.3x2.4 NBR Work?

The sealing function is generated through controlled compression of the circular elastomer cross-section.

For this product, the nominal cross-section diameter is 2.4 mm.

When installed in a correctly dimensioned groove, the O-ring is compressed between mating surfaces. Elastic deformation generates contact pressure against these surfaces and creates the sealing interface.

Effective sealing therefore depends on both the O-ring specification and the correct design of the installation groove.

O-Ring NBR 25.3x2.4 for Oils and Greases

NBR is commonly used in sealing arrangements involving many mineral oils and mineral greases.

However, general oil resistance should not be interpreted as universal compatibility with every lubricant, fuel or hydraulic fluid.

For a specific installation, the exact medium, additives, operating temperature and exposure conditions should be considered when selecting the sealing material.

Static and Dynamic Sealing

O-rings are widely used in static sealing arrangements and may also be used in appropriately engineered dynamic systems.

Static applications involve no intended relative movement between the mating sealing surfaces.

Dynamic applications introduce additional factors including friction, lubrication, movement speed, surface finish and wear.

The 25.3x2.4 mm, NBR and 70 ShA specification alone does not confirm suitability for every dynamic application.

1000-Piece Industrial Bulk Pack

This product page specifically covers:

O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs)

The package contains 1000 GRN O-rings with the same nominal dimensional and material specification.

This bulk quantity is particularly suitable for higher-volume requirements such as industrial assembly, serial production, maintenance departments, technical service operations and warehouse inventory.

The product naming sequence for this bulk variant remains:

O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs)

This intentionally differentiates it from the smaller 100-piece package.

1000 pcs vs 100 pcs - Product Variant Difference

The same nominal O-ring specification may be sold in different package quantities.

For SEO and product identification, the variants are intentionally separated as:

100 pcs: O-Ring 25.3x2.4 NBR 70 ShA (100 pcs)

1000 pcs: O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs)

The 1000-piece version is positioned as an industrial bulk package for higher consumption, while the 100-piece version serves customers requiring a smaller technical stock.

This distinction helps separate the purchasing intent and semantic focus of the two product pages.

Selection and Interchangeability

When selecting an equivalent for O-Ring NBR 25.3x2.4 mm 70 ShA, verify:

Inside Diameter: d1 = 25.3 mm
Cross-Section: d2 = 2.4 mm
Material: NBR
Hardness: 70 ShA
Dimensional tolerances
Medium compatibility
Operating temperature
Groove geometry

Matching the nominal 25.3x2.4 mm dimensions alone does not confirm full interchangeability.

An O-ring manufactured from FKM, EPDM or VMQ may have identical nominal dimensions but different chemical and thermal characteristics.

Technical Specification

Product Name: O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs)
Product Type: O-ring / elastomer sealing ring
Brand: GRN
Nominal Size: 25.3x2.4 mm
d1 - Inside Diameter: 25.3 mm
d2 - Cross-Section Diameter: 2.4 mm
Nominal Outside Diameter: 30.1 mm
Material: NBR
Material Name: Nitrile Butadiene Rubber
Hardness: 70 ShA / 70 Shore A
Cross-Section: Circular
Package Quantity: 1000 pcs
Package Type: Industrial bulk package

FAQ

What are the dimensions of O-Ring NBR 25.3x2.4 mm 70 ShA?

The O-ring has a 25.3 mm inside diameter and 2.4 mm cross-section diameter. Its nominal outside diameter is 30.1 mm.

What does 25.3x2.4 mm mean for an O-ring?

25.3 mm is the inside diameter, while 2.4 mm is the diameter of the circular cross-section.

What is the outside diameter of O-Ring 25.3x2.4?

The nominal outside diameter is 30.1 mm, calculated as 25.3 + 2 x 2.4 = 30.1 mm.

What does NBR mean?

NBR means Nitrile Butadiene Rubber, an elastomer widely used for technical sealing components.

What does 70 ShA mean?

70 ShA specifies a nominal hardness of 70 Shore A. It describes elastomer hardness and is not a pressure rating.

Can O-Ring NBR 25.3x2.4 be used with oil?

NBR is compatible with many mineral oils and greases. Suitability should still be verified for the exact operating fluid, additives and temperature.

How many O-rings are included in the package?

O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs) contains 1000 GRN sealing rings.

Is there also a 100-piece version?

Yes. The 100-piece package is treated as a separate commercial variant with a different product naming structure and search intent.

Which package is better for industrial use?

For regular high-volume consumption, the 1000-piece bulk package provides a larger technical stock and reduces the need for frequent replenishment.

AI OVERVIEW

O-Ring NBR 25.3x2.4 mm 70 ShA (1000 pcs) is an industrial bulk package of 1000 GRN nitrile rubber sealing rings with a nominal hardness of 70 Shore A. Each O-ring has a 25.3 mm inside diameter, 2.4 mm circular cross-section and 30.1 mm nominal outside diameter. The bulk package is intended for higher-volume industrial, maintenance and technical supply requirements.