X-Rings - NBR Nitrile, 70 Shore A
X-rings, also known as quad rings, are sealing rings with a four-lobed, X-shaped cross-section. Each side of the ring has two sealing contact lines, so it seals effectively with less compression than a standard O-ring. This means lower friction, less wear and less chance of the ring twisting in the groove. X-rings can be used in both static and dynamic applications, and the seal tightens as system pressure rises.
These X-rings are made from NBR (nitrile butadiene rubber), which has excellent resistance to mineral oils, hydraulic fluids and greases, along with good strength and wear resistance. At 70 Shore A, the material offers a good balance of flexibility and durability, making it the standard choice for general-purpose sealing.
Chemical Compatibility
Limitations
Not recommended for use with aromatic hydrocarbons, chlorinated hydrocarbons, ketones (such as acetone), esters, strong acids, glycol-based brake fluids, phosphate-ester hydraulic fluids or methanol. Petrol with a high aromatic or ethanol content may need a specialist grade. NBR has limited resistance to ozone, sunlight and weathering, so it should not be used where it will be exposed outdoors for long periods.
Applications
Hydraulic and pneumatic cylinders, valves, pumps, fuel and lubrication systems, and general industrial machinery.
Installation Guidance
X-rings fit most standard O-ring grooves. For dynamic applications, a slightly deeper groove gives better results. The 70 Shore A compound is flexible enough to fit easily and to seal well against a range of surface finishes. For high-pressure applications or larger clearance gaps, a harder grade or back-up rings may be required to prevent extrusion. Apply a thin film of compatible lubricant before fitting, and do not stretch the ring over sharp edges or threads.
All dimensions are nominal. The information provided by AH Design Components Ltd is for reference only and is not a manufacturing specification. Please confirm the product is suitable for your application before use.