Value Collection ZMSCHB90233 O-ring Backup Ring Nbr

Product Description

The VALUE COLLECTION ZMSCHB90233 is a rectangular-cross-section backup ring O-ring made from Nitrile Butadiene Rubber (NBR), designed to prevent extrusion in high-pressure sealing applications. It measures 2.881 inches inside diameter, 3.117 inches outside diameter, and 0.0468 inches thick, conforming to Dash Number 8-233. With a durometer hardness rating of 90 (Extra Hard), this backup ring provides firm resistance against pressure-induced deformation. It handles a temperature range of -40 to 250 degrees F, making it suitable for a wide range of hydraulic, pneumatic, and fluid-handling systems where NBR chemical compatibility is appropriate.

This backup ring is used in hydraulic cylinders, pneumatic fittings, plumbing assemblies, and industrial fluid-transfer systems where standard O-rings require extrusion protection. The Dash 8-233 designation makes it straightforward to cross-reference and source for maintenance and repair work. It is commonly installed by plumbers, pipefitters, hydraulic technicians, and industrial maintenance professionals. Each package contains 25 pieces, with a minimum order quantity of 1 package.

Key Features

• Rectangular cross section functions as a backup ring to prevent O-ring extrusion under pressure
• Nitrile Butadiene Rubber construction offers solid resistance to petroleum-based fluids and oils
• 90 durometer Extra Hard hardness rating provides firm support in high-pressure sealing grooves
• Dash Number 8-233 designation for easy cross-reference with standard O-ring sizing charts
• Operating temperature range of -40 to 250 degrees F suits a broad range of service environments
• Package quantity of 25 pieces supports stocking for service fleets and repair benches

Compatibility

Designed as an OEM-style replacement backup ring for hydraulic, pneumatic, and fluid-handling assemblies requiring a Dash 8-233 rectangular NBR sealing element.

Installation Notes

Backup rings are installed by plumbers, pipefitters, and hydraulic or pneumatic technicians. Depressurize and isolate the system completely before disassembling any fitting or cylinder that contains this ring. Inspect the sealing groove for burrs or damage before seating the backup ring, and ensure the NBR material is chemically compatible with the system fluid. Follow applicable IPC or system-manufacturer guidelines for groove dimensions and assembly torque.