Value Collection ZMSCHB90260 Nbr Backup O-ring Dash 8-260

Product Description

The VALUE COLLECTION ZMSCHB90260 is a rectangular cross-section backup O-ring made from Nitrile Butadiene Rubber (NBR), sold in a pack of 5. It carries a Dash 8-260 designation and measures 6.518 inches inside diameter by 6.756 inches outside diameter, with a thickness of 0.0468 inches. Rated at 90 durometer, this extra-hard backup ring is engineered to prevent extrusion of primary O-rings under pressure in dynamic and static sealing applications. The NBR compound provides solid resistance to petroleum-based fluids, hydraulic oils, and fuels across a working temperature range of -40 to 250 degrees F. Licensed plumbers, hydraulic system technicians, and industrial maintenance professionals install this type of backup ring as part of a complete seal assembly.

This backup ring is suited for high-pressure sealing assemblies where a primary O-ring requires lateral support to prevent blowout or extrusion into clearance gaps. Typical applications include hydraulic cylinders, fluid power components, pneumatic actuators, and industrial plumbing connections where a Dash 8-260 size is specified. The rectangular cross section seats flush against the primary seal, making it compatible with standard O-ring gland geometries designed for backup ring use. Each order ships as a pack of 5 rings.

Key Features

• Dash 8-260 designation for straightforward cross-reference with standard O-ring size charts
• Rectangular cross section prevents primary O-ring extrusion under elevated pressure
• 90 durometer extra-hard NBR compound resists petroleum-based oils, hydraulic fluid, and fuels
• Operating temperature range of -40 to 250 degrees F suits a wide range of industrial and fluid power environments
• 6.518 inches ID and 6.756 inches OD provide a precise fit in standard Dash 8-260 glands
• Pack of 5 rings per order supports service stock and field repair kits

Compatibility

Designed as a standard Dash 8-260 backup O-ring for use in hydraulic, pneumatic, and fluid power sealing assemblies that require a rectangular-section backup ring alongside a primary O-ring seal.

Installation Notes

Installation is typically performed by hydraulic technicians, licensed plumbers, or industrial maintenance personnel. Depressurize and isolate the system completely before disassembling any seal gland. Inspect the gland groove for scoring or debris before seating the backup ring, and install the backup ring on the low-pressure side of the primary O-ring. Do not stretch the backup ring beyond the minimum required to seat it, as distortion can compromise sealing performance.