90 Shore A High Hardness NBR O-Ring for Heavy-Duty Hydraulic Sealing Rubber O Ring

Custom NBR 90 Shore A O-Rings with High Hardness for Heavy-Duty Hydraulic Sealing

NBR 90 Shore A O-rings are high-hardness rubber sealing components designed for demanding hydraulic sealing applications. Manufactured from nitrile butadiene rubber (NBR), these O-rings offer good oil resistance, high mechanical strength, and reliable sealing performance in hydraulic systems operating under challenging conditions.

With a hardness of 90 Shore A, these NBR O-rings provide greater resistance to deformation and extrusion compared with softer rubber compounds. Their high hardness makes them suitable for sealing applications where increased mechanical support and dimensional stability are required, particularly in hydraulic equipment exposed to elevated operating pressures.

NBR 90 Shore A also provides good resistance to mineral-based hydraulic oils, lubricating oils, and petroleum-based fluids. Combined with good wear resistance and mechanical durability, these O-rings are a practical sealing solution for heavy-duty hydraulic cylinders, pumps, valves, and industrial machinery.

Custom NBR 90 Shore A O-rings can be manufactured according to specific dimensions, technical drawings, or physical samples to meet different equipment sealing requirements.

Material Advantages of NBR 90 Shore A

NBR (Nitrile Butadiene Rubber), also known as Buna-N, is widely used in industrial sealing applications due to its good oil resistance and mechanical properties. The 90 Shore A hardness grade is particularly suitable for applications requiring a harder rubber sealing material.

High Hardness and Mechanical Strength

With a hardness of 90 Shore A, NBR O-rings provide increased resistance to mechanical deformation compared with standard 70 Shore A compounds. This makes them suitable for demanding sealing environments where dimensional stability and mechanical support are important.

Improved Resistance to Extrusion

Harder NBR compounds can provide better resistance to extrusion through sealing clearances under pressure. This is particularly beneficial in hydraulic applications where pressure fluctuations and extrusion gaps may affect seal performance. Actual extrusion resistance also depends on pressure, clearance, temperature, and groove design.

Good Hydraulic Oil Resistance

NBR offers good compatibility with many mineral-based hydraulic oils, lubricating oils, and petroleum-based fluids. It helps maintain sealing integrity when the rubber compound is properly matched to the working medium.

Good Wear and Abrasion Resistance

NBR provides good resistance to abrasion and mechanical wear, making it suitable for industrial equipment and selected dynamic sealing applications.

Reliable Sealing Performance

The combination of high hardness and good mechanical strength helps maintain the O-ring's shape under suitable operating conditions, supporting consistent sealing contact and reducing the risk of leakage.

Cost-Effective Industrial Sealing Material

NBR offers a practical balance of performance and cost, making it a widely used material for heavy-duty industrial and hydraulic sealing applications.

NBR 90 Shore A vs. NBR 70 Shore A O-Rings

Choosing the correct O-ring hardness is important for hydraulic sealing performance. NBR 70 Shore A and NBR 90 Shore A are commonly used hardness grades, but they serve different sealing requirements.

FAQ

Q1: What are NBR 90 Shore A O-rings used for?

NBR 90 Shore A O-rings are used in heavy-duty hydraulic cylinders, pumps, valves, hydraulic manifolds, and industrial machinery. They are suitable for sealing applications requiring higher rubber hardness, good oil resistance, and improved resistance to mechanical deformation.

Q2: Why choose 90 Shore A instead of 70 Shore A for hydraulic O-rings?

NBR 90 Shore A is harder and generally provides better resistance to deformation and extrusion under suitable operating conditions. It is often selected for hydraulic applications involving higher pressures or larger extrusion clearances. NBR 70 Shore A is more flexible and easier to install, making it suitable for general-purpose sealing.

Q3: Are NBR 90 Shore A O-rings suitable for high-pressure hydraulic systems?

They can be used in selected high-pressure hydraulic sealing applications because of their higher hardness and improved extrusion resistance. However, hardness alone does not determine pressure capability. The maximum working pressure also depends on the O-ring dimensions, groove design, extrusion gap, temperature, and whether backup rings are required.

Q4: Are NBR 90 Shore A O-rings resistant to hydraulic oil?

Yes. NBR has good resistance to many mineral-based hydraulic oils, lubricating oils, and petroleum-based fluids. Compatibility should be confirmed according to the actual hydraulic fluid composition and operating temperature.