Value Collection ZMSCH70391 O-ring Dash 391 Nitrile 22 in Id

Product Description

The VALUE COLLECTION ZMSCH70391 is a Dash 391 O-ring manufactured from Buna-N (Nitrile Butadiene Rubber), one of the most widely used elastomers in fluid-sealing applications. It measures 22 inches inside diameter, 22-3/8 inches outside diameter, and 3/16 inches thick with a round cross section. Shore hardness is rated at 70, placing it in the hard hardness category. The material delivers excellent resistance to petroleum-based fluids, strong compression set retention, and good tear and abrasion resistance. Plumbers, pipefitters, and mechanical contractors install this type of seal in large-bore piping systems, pumps, and fluid-handling assemblies.

This O-ring is suited for static and low-dynamic sealing applications where petroleum-product compatibility is required. Its large 22-inch bore makes it appropriate for industrial or commercial piping flanges, tank covers, large pump housings, and similar equipment. The Buna-N compound performs across a temperature range of -40 degrees F to 250 degrees F, making it viable in both cold-climate utility installations and moderate-heat process environments. It should not be stored in direct sunlight or near motors and other electrical equipment that may generate ozone, as ozone degrades nitrile rubber.

Key Features

• Buna-N (Nitrile Butadiene Rubber) compound — the most widely used O-ring elastomer for petroleum-fluid sealing
• 22 inches inside diameter x 22-3/8 inches outside diameter x 3/16 inches thick, round cross section
• Shore hardness 70 (hard rating) for reliable compression set and extrusion resistance
• Operating temperature range: -40 degrees F to 250 degrees F
• Excellent resistance to petroleum products, including oils, fuels, and hydraulic fluids
• Meets SAE and MIL-Spec standards

Compatibility

Compatible with petroleum-based products and fluids. Designed as an OEM-style replacement or maintenance seal for large-bore flanges, pump housings, tank covers, and piping assemblies requiring a Dash 391 Buna-N O-ring.

Installation Notes

Installation is typically performed by licensed plumbers, pipefitters, or mechanical technicians. Depressurize and drain the system completely before removing the old seal. Inspect the mating groove for nicks, corrosion, or debris that could compromise the seal surface. Avoid installing over sharp edges without a proper installation tool, as nicking the elastomer will cause premature failure.