Engineered for demanding hydraulic and pneumatic applications, this Buna-N (Nitrile) 90 Durometer Back-Up Ring with a 3/16" cross section is designed to prevent O-ring extrusion under high-pressure conditions. When installed alongside an O-ring, it bridges the extrusion gap and extends seal life — making it an essential component in cylinders, valves, and actuators operating at elevated pressures.
Key Features
Material: Buna-N (Nitrile Rubber) — excellent resistance to petroleum-based hydraulic fluids, oils, and fuels
Durometer: 90 Shore A — high hardness for superior extrusion resistance in high-pressure systems
Cross Section: 3/16" — compatible with standard AS568 O-ring grooves of the same cross section
Temperature Range: -40°F to +250°F (-40°C to +121°C)
Pressure Rating: Suitable for high-pressure hydraulic applications where standard O-rings require anti-extrusion support
Applications
Hydraulic cylinders and actuators
Pneumatic systems
Valves and manifolds
High-pressure fluid power equipment
Compatibility
Compatible with petroleum-based hydraulic fluids, mineral oils, water-glycol fluids, and most common industrial lubricants. Not recommended for use with phosphate ester fluids, ketones, or strong acids.
