568-438 BUNA 70 SQUARE CUT RINGS

SH70438 is an AS568-438 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring built to an inside diameter of 6.225 in (158.12 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.775 in (172.09 mm). In service, this square-cut ring provides an economical lathe-cut alternative where a moulded o-ring is not required.

Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, most widely specified general-purpose sealing elastomer. This material stands up to water, greases and lubricants, and propane and butane. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Applications involving ozone and direct sunlight or ketones call for a different compound. The profile itself contributes greater resistance to extrusion than a round section of the same size and a flat contact band that spreads sealing load across a wider area. 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 agricultural equipment, hydraulic and pneumatic systems, and construction equipment.

SH70438 ships individually. Unit weight is approximately 24.506 g and nominal inside diameter is listed as 6 1/4 inch. Review your operating media and conditions against this specification before installation.