Part number H3X31 is a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 31 mm (1.22 in), a cross section of 3 mm (0.118 in), and an outside diameter of 37 mm (1.46 in). An o-ring creates a positive seal at flange, piston and rod interfaces without added hardware.
The material holds up against propane and butane, many alcohols, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) delivers the most widely specified general-purpose sealing elastomer and an economical choice for high-volume maintenance programs. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with strong acids or ozone and direct sunlight.
It sees regular use in fluid power, agricultural equipment, and construction equipment.
Stocked as H3X31 and sold individually. Unit weight is approximately 0.92 g. Check the compound against your process media, pressure and temperature before committing to a design. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Description 3MM CS X 31MM ID BLACK BUNA 70D
Actual Outside Diameter 37 mm (1.46 inch)
Actual Cross Section 3 mm (0.118 inch)
Actual Inside Diameter 31 mm (1.22 inch)
Measurement System Metric
Product Category O-Rings - Metric - Commodity