O-ring 278.77x5.33 NBR

Technical specifications and material

The O-ring 278.77x5.33 NBR 70 ShA is a precision rubber sealing ring designed for professional industrial applications. With an inner diameter of 278.77 mm and a cross-section of 5.33 mm, it is made from NBR (nitrile butadiene rubber) with a hardness of 70 Shore A - the most popular compound for hydraulic and pneumatic sealing systems.
This technical O-ring ensures excellent resistance to oils, greases, hydraulic fluids, and fuels, while maintaining flexibility and dimensional stability. Its properties make it ideal for static seals, as well as slow dynamic applications under moderate pressure and temperature conditions.

Search data in Poland shows frequent queries like “oring 278.77x5.33 NBR”, “NBR 70 O-ring 278.77 mm”, and “oil-resistant rubber seal 278x5 mm”, confirming its relevance in industrial and service supply sectors.

Industrial applications and B2B advantages

The 278.77x5.33 NBR 70 ShA O-ring is widely used in hydraulic and pneumatic systems, pumps, valves, compressors, and static flanges.
For B2B customers, it offers key operational benefits:

• High resistance to mineral oils and lubricants,

• Long service life in industrial environments,

• Excellent sealing reliability with minimal maintenance,

• Compatibility with DIN 3771 O-ring grooves, ensuring easy installation and replacement.

This product is ideal for distributors, maintenance departments, and production facilities requiring reliable technical seals with consistent performance.

Installation and performance recommendations

Before installation, clean the groove and shaft thoroughly to remove debris or sharp edges. Lightly lubricate the O-ring with compatible oil or grease to prevent twisting during assembly.
The NBR 70 compound allows operation at temperatures from −30 °C to +100 °C, depending on the medium and application. For higher temperatures or chemical exposure, materials such as FKM (Viton®) or EPDM are recommended.
When properly installed, the O-ring ensures leak-free operation and extends maintenance intervals, reducing downtime in industrial systems.

FAQ - Frequently Asked Questions

Q1: What material is the O-ring made from?
A1: It is made of NBR (nitrile rubber) with a hardness of 70 ShA, providing high oil resistance and flexibility for hydraulic and pneumatic sealing systems.

Q2: What are the main applications of this O-ring?
A2: It is used for static and low-motion sealing in hydraulic cylinders, pneumatic valves, pumps, compressors, and pipe connections.

Q3: How to choose the correct O-ring size?
A3: Match the inner diameter (278.77 mm) and cross-section (5.33 mm) to your groove and shaft dimensions, following DIN 3771 standards.

Q4: What are the temperature limits for NBR 70 ShA?
A4: The recommended range is −30 °C to +100 °C. For more extreme temperatures or aggressive media, consider upgrading to FKM (Viton®) or EPDM materials.

Q5: What is the delivery time for this product?
A5: 📍 Warehouse & Store: Lublin, ul. Smoluchowskiego 1, building 4
🚚 24h Delivery - fast order processing for B2B customers.