568-158 BUNA 70 SQUARE CUT RINGS

Part number SH70158 is an AS568-158 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring supplied with an inside diameter of 4.737 in (120.32 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 4.943 in (125.55 mm). A square-cut ring presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.

The material holds up against hydraulic fluids, water, and propane and butane. That behavior comes from the compound itself: Buna-N (Nitrile) is valued for reliable performance in both static and dynamic service, an economical choice for high-volume maintenance programs. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving automotive brake fluid or polar solvents call for a different compound. The profile itself contributes a rectangular section that will not roll in the groove 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.

Typical settings include fluid power, automotive, and construction equipment.

SH70158 ships individually. Unit weight is approximately 2.577 g. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.