Ordered as QH70176, this is an AS568-176 black Buna-N (Nitrile) 70 Shore A Quad-Ring measuring an inside diameter of 9.237 in (234.62 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 9.443 in (239.85 mm). The quad-ring uses a four-lobed profile to create two sealing surfaces per side, reducing the squeeze needed to seal.
As a material, Buna-N (Nitrile) delivers low compression set under sustained load, reliable performance in both static and dynamic service. It resists petroleum-based oils, greases and lubricants, and hydraulic fluids. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with automotive brake fluid or strong acids. The profile itself contributes two sealing bands per contact face rather than one and a parting line located away from the sealing surface.
Common environments for this compound include agricultural equipment, hydraulic and pneumatic systems, and general industrial maintenance.
Reference part number QH70176 when ordering; the item is sold individually. Nominal inside diameter is listed as 9 1/4 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. 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.
description Q-176 BUNA 70 Q RING
Actual_CS 0.103 inch (2.62 mm)
Actual_ID 9.237 inch (234.62 mm)
Actual_OD 9.443 inch (239.85 mm)
ProductCode Description O-Rings - Square/Quad - Commodity