This square-cut ring is supplied in AS568-329 black Buna-N (Nitrile) 70 Shore A measuring 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), catalogued under part number SH70329. It presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.
This material stands up to many alcohols, water, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for reliable performance in both static and dynamic service, strong abrasion and tear resistance. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where automotive brake fluid or strong acids are present. The profile itself contributes a rectangular section that will not roll in the groove and simple lathe-cut manufacture at low tooling cost. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.
You will find this material specified across general industrial maintenance, automotive, and fluid power.
This item is sold individually under part number SH70329. Unit weight is approximately 4.816 g and nominal inside diameter is listed as 2 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.
description 568-329 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 1.975 inch (50.17 mm)
Actual_OD 2.395 inch (60.83 mm)
ProductCode Description O-Rings - Square/Quad - Commodity