Connection Accessories

Most sealing washers for external threads consist of a combination of steel and NBR (nitrile butadiene rubber). Profile seals for SAE flanges are also made of NBR and are often labeled as “suitable for bio-oil.” This design is resistant to mineral oils, synthetic hydraulic fluids, and environmentally friendly bio-oils.

Sealing washers are available for both inch-based external threads and DIN metric external threads:

• Inch sizes: 1/8", 1/4", 3/8", 1/2", 5/8", 3/4", 1", 1 1/4", 1 1/2", 2"
• DIN metric sizes: M5, M6, M8, M10, M12, M14, M16, M17, M18, M20, M22, M24, M27, M30, M33, M42

This selection allows use in a wide range of hydraulic systems and mechanical engineering applications.

Sealing washers are used in a wide range of industries, including hydraulic and pneumatic systems, mechanical engineering, automotive engineering, agricultural engineering, and industrial plants. They provide reliable sealing for threaded connections and prevent the leakage of liquids or gases even under high pressure.

Steel sealing washers with an NBR sealing lip are generally suitable for temperatures from -30 °C to +100 °C. The permissible operating pressure can reach several hundred bar depending on size and design, typically 250–400 bar in hydraulic applications.

Sealing washers are installed directly between the threaded connection and the contact surface. Installation is carried out without additional sealing compounds. It is important to keep the contact surfaces clean, dry, and free of burrs to ensure optimal sealing. Excessive tightening torque should be avoided to prevent damage to the sealing lip.

• Material quality of steel and elastomer
• Operating pressure and temperature
• Compatibility of the medium with the NBR material
• Frequency of disassembly and reuse
• Cleanliness of the sealing surfaces

With proper selection and installation, sealing washers can provide reliable sealing for many years.