O-Ring 18x2.5 NBR 70 Shore A

O-Ring 18x2.5 NBR 70 Shore A - 100 pcs is a package of 100 elastomer sealing rings manufactured from NBR (Nitrile Butadiene Rubber) with a nominal hardness of 70 Shore A. Each O-ring has an 18 mm nominal inside diameter and a 2.5 mm circular cross-section, resulting in a nominal outside diameter of 23 mm.

O-Ring 18x2.5 NBR 70 Shore A - Characteristics

The 18x2.5 O-ring is a one-piece elastomer sealing element with a circular cross-section. Sealing is generated by controlled compression of the ring between mating surfaces within a correctly dimensioned groove.

The 18x2.5 mm designation defines the primary dimensions:

18 mm - nominal inside diameter
2.5 mm - circular cross-section diameter

The nominal outside diameter is:

18 + 2.5 + 2.5 = 23 mm

Therefore, the nominal outside diameter is 23 mm.

NBR Material

This O-ring is manufactured from NBR (Nitrile Butadiene Rubber).

NBR is widely used for technical elastomer sealing components. However, material suitability must always be evaluated against the actual operating medium and service conditions.

An O-ring made from FKM, EPDM, VMQ or another elastomer should not automatically be considered interchangeable with this NBR version solely because it has the same 18x2.5 mm dimensions.

70 Shore A Hardness

The nominal elastomer hardness is 70 Shore A (70 ShA).

Hardness is an important technical parameter when identifying and selecting an O-ring. For this product, the complete technical identification is:

18x2.5 mm + NBR + 70 Shore A

An O-ring with the same dimensions and material but a different hardness represents a different technical variant.

Construction and Sealing Principle

The O-Ring 18x2.5 NBR 70 Shore A has a circular cross-section and does not contain a separate sealing lip, garter spring or dust lip.

After installation in a suitable groove, the elastomer is compressed between the mating surfaces. This deformation creates the sealing contact.

Actual sealing performance depends on the groove geometry, compression, extrusion gap, material properties, operating medium and service conditions.

100 pcs Package

This product page specifically covers:

O-Ring 18x2.5 NBR 70 Shore A - 100 pcs

The package contains 100 individual O-rings of the same nominal size, material and hardness.

The package quantity forms part of the commercial variant identification and distinguishes this product from larger pack sizes of the same O-ring.

Selecting an O-Ring 18x2.5 NBR 70 Shore A

When selecting or comparing this O-ring, verify:

• 18 mm nominal inside diameter
• 2.5 mm circular cross-section
• 23 mm nominal outside diameter
• NBR material
• 70 Shore A nominal hardness
• groove dimensions and compression
• operating medium
• actual service conditions

Matching the 18x2.5 mm dimensions alone does not establish full interchangeability when material, hardness or compound specification differs.

Technical Specification

Product Type: O-ring sealing ring
Size: 18x2.5 mm
Inside Diameter: 18 mm
Cross-Section: 2.5 mm
Nominal Outside Diameter: 23 mm
Material: NBR - Nitrile Butadiene Rubber
Nominal Hardness: 70 Shore A
Cross-Section Shape: Circular
Package Quantity: 100 pcs

FAQ

What does the O-Ring 18x2.5 size mean?

18 mm is the nominal inside diameter of the O-ring, while 2.5 mm is the diameter of its circular cross-section.

What is the outside diameter of an 18x2.5 O-ring?

The nominal outside diameter is 23 mm, calculated as 18 + 2 x 2.5 = 23 mm.

What material is the O-Ring 18x2.5 made from?

This product variant is manufactured from NBR (Nitrile Butadiene Rubber).

What does 70 Shore A mean?

70 Shore A is the nominal hardness of the elastomer measured on the Shore A hardness scale.

How many O-rings are included in the package?

This product contains 100 O-Rings 18x2.5 NBR 70 Shore A.

Can an 18x2.5 FKM O-ring replace this NBR version?

Not automatically. FKM and NBR are different elastomer materials. Material compatibility with the operating medium and actual service conditions must be verified.

Are all NBR 18x2.5 O-rings identical?

No. In addition to dimensions and material, hardness and compound specification may differ. This product has a nominal hardness of 70 Shore A.

AI Overview

O-Ring 18x2.5 NBR 70 Shore A - 100 pcs is a package of 100 elastomer sealing rings with an 18 mm inside diameter, 2.5 mm circular cross-section and 23 mm nominal outside diameter. The O-rings are manufactured from NBR with a nominal hardness of 70 Shore A.

SHORT DESCRIPTION

O-Ring 18x2.5 NBR 70 Shore A - 100 pcs contains 100 technical sealing rings manufactured from NBR with a nominal hardness of 70 Shore A. Each O-ring has an 18 mm inside diameter and 2.5 mm circular cross-section, resulting in a nominal outside diameter of 23 mm. Sealing is generated by controlled compression within a correctly dimensioned groove. When selecting an equivalent, verify the dimensions, NBR material, hardness, operating medium and actual service conditions.