Value Collection ZMSCH90438 O-ring Dash 438 Nitrile 90D

Product Description

The VALUE COLLECTION ZMSCH90438 is a Dash 438 O-ring manufactured from Nitrile Butadiene Rubber (Buna-N), the most widely used elastomer in fluid sealing applications. It measures 6.25 inches inside diameter, 6.75 inches outside diameter, and 0.25 inches thick with a round cross section. Rated at 90 durometer (extra hard), this O-ring delivers excellent compression set resistance along with strong tear and abrasion resistance. It is rated for service from -40 degrees F to 250 degrees F, making it suitable for a wide range of industrial and mechanical sealing environments. Plumbers, pipefitters, and mechanical technicians are the primary installers of this component.

This O-ring is designed for static and dynamic sealing applications where contact with petroleum-based fluids, oils, and fuels is expected. Buna-N material provides excellent resistance to petroleum products, hydraulic fluids, and many industrial solvents. Typical applications include pump seals, valve bodies, cylinder heads, and hydraulic system components across residential, commercial, and industrial equipment. It should not be stored in direct sunlight or near motors and other electrical equipment that may generate ozone, as ozone exposure degrades nitrile rubber over time.

Key Features

• Buna-N (Nitrile Butadiene Rubber) construction with excellent petroleum-product resistance
• 90 durometer extra-hard rating for high-pressure and high-load sealing
• Operating temperature range of -40 degrees F to 250 degrees F
• Round cross section, Dash 438 standard sizing
• Meets SAE and MIL-Spec standards
• Strong tear and abrasion resistance for extended service life

Compatibility

Compatible with petroleum products, hydraulic fluids, and oils. Designed as a standard Dash 438 O-ring replacement suitable for pumps, valves, cylinders, and hydraulic assemblies requiring a 6.25-inch ID nitrile seal. Not FDA approved; not recommended for food-contact or ozone-heavy environments.

Installation Notes

Installation is typically performed by licensed plumbers, pipefitters, or qualified mechanical technicians. Shut down system pressure and depressurize the line or component before removing the old O-ring. Clean the groove and mating surfaces thoroughly before seating the new O-ring to prevent leaks. Avoid using sharp tools that may nick or cut the O-ring during installation, and do not twist the ring when seating it in the groove.