APG stocks the SH70442, an AS568-442 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring built to an inside diameter of 7.225 in (183.52 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 7.775 in (197.49 mm). A square-cut ring presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.
As a material, Buna-N (Nitrile) is known for an economical choice for high-volume maintenance programs and the most widely specified general-purpose sealing elastomer. This material stands up to propane and butane, hydraulic fluids, and greases and lubricants. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Verify compatibility before use with ozone and direct sunlight or automotive brake fluid. The profile itself contributes a flat contact band that spreads sealing load across a wider area and greater resistance to extrusion than a round section of the same size. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.
Common environments for this compound include general industrial maintenance, construction equipment, and agricultural equipment.
SH70442 ships individually. Unit weight is approximately 33.7575 g. Application requirements vary, so validate compatibility with your process conditions prior to installation.
description 568-442 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.275 inch (6.99 mm)
Actual_ID 7.225 inch (183.52 mm)
Actual_OD 7.775 inch (197.49 mm)
ProductCode Description O-Rings - Square/Quad - Commodity