Value Collection ZMSCHB90122 O-ring Backup Ring Nbr 50 Pack

Product Description

The VALUE COLLECTION ZMSCHB90122 is a rectangular-cross-section backup ring O-ring made from Nitrile Butadiene Rubber (NBR), rated at 90 durometer for extra-hard sealing performance. It measures 1.143 inches inner diameter, 1.316 inches outer diameter, and 0.0468 inches thick (equivalent to 3/64 inch). The part carries Dash Number 8-122 and is rated for service from -40 degrees F to 250 degrees F. Licensed plumbers, pipefitters, hydraulic technicians, and HVAC service pros install this type of backup ring to prevent O-ring extrusion under pressure in hydraulic, pneumatic, and fluid-handling assemblies.

This backup ring is suited for residential and light commercial applications where NBR elastomers are compatible with the media being sealed, including petroleum-based oils, water, and many hydraulic fluids. The rectangular cross section seats against standard Dash 8-122 groove geometry and works in conjunction with a primary O-ring to control extrusion gaps in dynamic and static seal assemblies. Sold in a package of 50 rings, making it practical for shop stock or service van inventory.

Key Features

• Dash 8-122 designation for positive groove-geometry identification
• Rectangular cross section controls O-ring extrusion under pressure cycling
• 90 durometer extra-hard NBR compound resists deformation at elevated temperatures
• Rated from -40 degrees F to 250 degrees F for broad service range
• NBR material compatible with petroleum-based hydraulic fluids, oils, and water
• Package quantity of 50 pieces supports shop-stock and bulk service needs

Compatibility

Designed as an OEM-style replacement or service backup ring for hydraulic, pneumatic, and fluid-handling seal assemblies requiring a Dash 8-122 rectangular-section ring in Nitrile Butadiene Rubber.

Installation Notes

Installation is typically performed by licensed plumbers, pipefitters, or hydraulic technicians following applicable system-specific codes and manufacturer service procedures. Always depressurize and de-energize the system fully before disassembling any seal cavity. Clean the groove and mating surfaces of contaminants and inspect for wear or damage before seating the backup ring. Do not roll or twist the ring during installation, as deformation of the rectangular cross section compromises sealing effectiveness.