Q-138 BUNA 70 Q RING

The QH70138 is an AS568-138 black Buna-N (Nitrile) 70 Shore A Quad-Ring with an inside diameter of 2.112 in (53.64 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.318 in (58.88 mm). This quad-ring delivers lower friction and better sealing stability than a comparable round-section o-ring.

Buna-N (Nitrile) is widely chosen for reliable performance in both static and dynamic service, the most widely specified general-purpose sealing elastomer. The material holds up against propane and butane, many alcohols, and petroleum-based oils. 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 a parting line located away from the sealing surface and lower compressive load required to achieve a seal.

You will find this material specified across fluid power, general industrial maintenance, and automotive.

QH70138 ships individually. Unit weight is approximately 1.1251 g. Check the compound against your process media, pressure and temperature before committing to a design. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.