Value Collection ZMSCH90431 O-ring Dash 431 Nitrile 90D

Product Description

The VALUE COLLECTION ZMSCH90431 is a Dash 431 O-ring manufactured from Nitrile Butadiene Rubber (Buna-N), the most widely used elastomer in fluid sealing applications. It measures 5.25 inches inside diameter by 5.75 inches outside diameter with a 0.25-inch cross-section thickness and a 90 durometer hardness rating, placing it in the extra-hard classification. The round cross-section profile seats into standard Dash 431 O-ring grooves. Plumbers, pipefitters, HVAC technicians, and maintenance professionals use this O-ring wherever a large-diameter, petroleum-resistant static or dynamic seal is required. It is sold in a package quantity of 10.

This O-ring is suited for applications involving petroleum-based fluids, hydraulic oils, fuels, and common industrial lubricants. Its temperature rating of -40 to 250 degrees F makes it appropriate for both refrigerated environments and moderate-heat service. Typical installations include large-bore pipe flanges, pump housings, valve bodies, and equipment access covers in commercial HVAC, plumbing, and industrial fluid-handling systems. The extra-hard 90 durometer compound resists extrusion under higher pressure conditions compared to standard 70-durometer Buna-N rings.

Key Features

• Buna-N (Nitrile Butadiene Rubber) compound offers excellent resistance to petroleum products and hydraulic fluids
• 90 durometer extra-hard rating provides strong extrusion resistance in pressurized applications
• Operating range of -40 to 250 degrees F covers a wide range of service environments
• Excellent compression set, tear resistance, and abrasion resistance for long service life
• Meets SAE and MIL-Spec standards
• Round cross-section conforms to standard Dash 431 O-ring groove dimensions

Compatibility

Designed as a standard Dash 431 O-ring replacement compatible with petroleum products and equipment calling for Buna-N seals. Should not be used with ozone-generating environments, direct sunlight exposure, or near motors and electrical equipment that produce ozone. Not FDA approved for food-contact applications.

Installation Notes

Installation is performed by plumbers, pipefitters, or HVAC technicians following applicable IPC or system manufacturer guidelines. Depressurize and drain the system completely before removing the old O-ring or installing the replacement. Inspect the groove for nicks, burrs, or contamination before seating the new O-ring. A compatible petroleum-based or system-approved lubricant may be used to ease installation and reduce the risk of tearing during assembly.