O-ring 239.3x5.7 NBR 90 ShA

Applications of the O-ring 239.3x5.7 NBR 90 ShA

The O-ring 239.3x5.7 NBR 90 ShA is a heavy-duty rubber sealing ring designed for reliable technical sealing in demanding industrial environments. Due to its large inner diameter and robust 5.7 mm cross-section, it is primarily used as a static seal in flanges, housings, covers and large machine components where high mechanical loads and pressure stability are required.

This O-ring is widely applied in hydraulic and pneumatic systems, industrial machinery, power engineering installations and maintenance operations. It is particularly suitable for applications where standard 70 ShA seals may be insufficient, and increased hardness is required to maintain long-term sealing integrity.

NBR Material Benefits and High Resistance

Manufactured from NBR (nitrile rubber), this O-ring offers excellent resistance to oils and grease, especially mineral-based hydraulic oils, lubricants and fuels. The 90 ShA hardness provides enhanced resistance to extrusion and deformation under pressure, making it ideal for high-load static sealing applications.

NBR also delivers good resistance to abrasion and aging, ensuring stable performance over extended service periods. The material maintains its sealing properties within typical operating temperature ranges used in hydraulic and pneumatic installations, offering high durability and operational reliability.

Technical Specifications

• Product type: O-ring / rubber sealing ring

• Material: NBR (nitrile rubber)

• Hardness: 90 ShA

• Inner diameter: 239.3 mm

• Cross-section: 5.7 mm

• Sealing type: static sealing

• Resistance: oils, grease, fuels

• Applications: industrial applications, hydraulics, pneumatics

FAQ - Frequently Asked Questions

What is the O-ring 239.3x5.7 NBR 90 ShA used for?
It is used for static sealing in large flanges, housings and industrial machine components.

What is the advantage of 90 ShA hardness?
Higher hardness improves resistance to pressure, extrusion and deformation compared to standard 70 ShA O-rings.

Is NBR suitable for hydraulic oil?
Yes, NBR provides very good resistance to mineral-based hydraulic oils and lubricants.

Can this O-ring be used in pneumatic systems?
Yes, it is suitable for pneumatic applications, especially where higher sealing stability is required.

How do I select the correct O-ring?
Choose the correct inner diameter, cross-section, hardness and material based on operating pressure, medium and temperature.