Q-329 BUNA 70 Q RING

Part number QH70329 is an AS568-329 black Buna-N (Nitrile) 70 Shore A Quad-Ring with an inside diameter of 1.975 in (50.17 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 2.395 in (60.83 mm). A quad-ring provides a dual sealing band on each contact face for improved reliability.

The compound resists water, propane and butane, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) is valued for low compression set under sustained load, reliable performance in both static and dynamic service. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Exposure to ketones or polar solvents will shorten service life. The profile itself contributes resistance to the spiral twisting that defeats round-section rings and lower compressive load required to achieve a seal.

You will find this material specified across hydraulic and pneumatic systems, automotive, and agricultural equipment.

Order part number QH70329, sold individually. Unit weight is approximately 5.076 g and nominal inside diameter is listed as 2 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.