O-ring 207x4 NBR

Applications

The O-ring 207x4 NBR 70Shore is engineered for demanding industrial sealing tasks where a large-diameter rubber gasket is required. With an inner diameter of 207 mm and cross-section of 4 mm, this sealing ring is ideal for machinery components, hydraulic cylinders, pneumatic systems, and other heavy-duty applications. The nitrile rubber (NBR) compound with 70 Shore A hardness ensures excellent resistance to mineral oils, greases, fuels and many chemical media, fulfilling critical requirements for industrial sealing.

Advantages

• High durability & chemical resistance - NBR (nitrile-butadiene rubber) is widely recognised for its excellent performance in oil-exposed environments and hydraulic/pneumatic applications.

• Large-format sealing capability - At ID 207 mm and CS 4 mm, this O-ring addresses applications not covered by standard smaller sizes; excellent for heavy-machinery, housings or large-bore cylinders.

• Optimised hardness - 70 Shore A hardness provides a balanced combination of flexibility and strength, maintaining sealing integrity under pressure and vibration.

• Packaged for B2B - Supplied in bulk packages, ideal for maintenance departments, industrial service providers and OEMs.

• Cost-effective seal solution - The simple geometry of the O-ring allows straightforward installation and minimal downtime, reducing total cost of ownership.

Technical Data

• Material: Nitrile Rubber (NBR)

• Hardness: 70 Shore A

• Inner Diameter (ID): 207 mm

• Cross-Section (CS): 4 mm

• Operating Temperature: Standard range approx. −30 °C to +100 °C (short-term up to +120 °C), subject to media and conditions.

• Typical Media Compatibility: Mineral oils, hydraulic fluids H/H-L/H-LP, animal & vegetable oils, silicone greases, aliphatic hydrocarbons.

• Limitations: Not recommended for UV exposure, ozone, aromatic hydrocarbons, glycol-based brake fluids or high-aromatic fuels.

Frequently Asked Questions (FAQ)

Q1: What does “207x4 NBR 70Shore” mean?
A1: It denotes an O-ring with inner diameter 207 mm, cross-section (cord thickness) 4 mm, manufactured from nitrile rubber (NBR) with a hardness of 70 Shore A.

Q2: In what applications can this O-ring be used?
A2: Ideal for industrial hydraulic cylinders, pneumatic equipment, large-diameter housings, machine tools, and general sealing tasks in oil- and grease-exposed environments.

Q3: Is the material suitable for high oil or fuel exposure?
A3: Yes - NBR 70 Shore A provides good resistance to mineral oils, hydraulic fluids and many hydrocarbons. For extremely aggressive fuels or UV exposed conditions, a different elastomer may be considered.

Q4: What temperature range does this O-ring support?
A4: Typically −30 °C to +100 °C continuous operation (with short-term capability up to +120 °C), depending on specific media and dynamic loading conditions.

Q5: Can this be installed in dynamic (rotating) applications?
A5: Yes - however, for dynamic (especially high-speed or reciprocating) sealing, additional considerations such as seal groove design, lubrication and material wear must be evaluated to ensure long term performance.