RS PRO Nitrile Rubber (NBR) O-Ring, 0.375 in ID, 0.5 in OD, 70 Shore Hardness, 689-631

RS PRO 689-631 Nitrile Rubber (NBR) O-Ring is a high-quality industrial sealing component designed for a wide range of demanding engineering applications. Manufactured from premium nitrile rubber, this O-ring delivers superior resistance to petroleum-based oils, greases, and abrasion, making it a preferred choice for environments requiring robust and durable sealing solutions.

This O-ring features an inside diameter of 0.375 inch and an outside diameter of 0.5 inch, with a thickness of 0.0625 inch. Its 70 Shore hardness ensures an optimal balance between flexibility and strength, resulting in reliable sealing performance under fluctuating pressures and temperatures. The material's intrinsic properties allow the O-ring to maintain its integrity in continuous operating temperatures from -30°C up to 120°C, with capability for intermittent short-term exposure to higher temperatures up to 135°C as per industry use cases.

Nitrile rubber (NBR), the material used in this O-ring, is recognized for its excellent resistance to mineral hydraulic oils and greases, which is critical for automotive, hydraulic, and mechanical systems. The O-ring is suitable for static and dynamic sealing in pipes, pumps, valves, and mechanical assemblies across diverse sectors including automotive maintenance, plumbing installations, aerospace mechanisms, and general engineering environments. Care should be taken to avoid using this O-ring with esters, ozone, ketones, aldehydes, or chlorinated and nitro hydrocarbons due to chemical incompatibility.

The black color of the O-ring supports quick visual identification during equipment maintenance and assembly. Its precise sizing and compliant materials ensure compatibility with both imperial and metric sealing requirements, useful for retrofit and new-build applications alike. The O-ring conforms to industry mechanical gasket standards and provides users with an affordable, long-lasting solution for maintaining leak-free performance in challenging working conditions.

Industrial and laboratory engineers choose RS PRO O-rings for dependable sealing in machinery, pumps, and systems where fluid or air-tight integrity is essential. The product is manufactured with rigorous quality control for consistency and reliability across all delivered units.

Explore more Nitrile Rubber O-Rings and gasket solutions by RS PRO under the Gasket & Seal category.

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