SH70211 is an AS568-211 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring measuring an inside diameter of 0.796 in (20.22 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.074 in (27.28 mm). In service, this square-cut ring presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.
Buna-N (Nitrile) is known for low compression set under sustained load, reliable performance in both static and dynamic service. The compound resists many alcohols, water, and greases and lubricants. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). The profile itself contributes simple lathe-cut manufacture at low tooling cost 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 automotive, construction equipment, and hydraulic and pneumatic systems.
SH70211 ships individually. Unit weight is approximately 1.0699 g. As always, verify media compatibility and operating conditions against the requirements of your specific application. 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 568-211 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 0.796 inch (20.22 mm)
Actual_OD 1.074 inch (27.28 mm)
ProductCode Description O-Rings - Square/Quad - Commodity