568-240 BUNA 70 SQUARE CUT RINGS

SH70240 is an AS568-240 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring supplied with an inside diameter of 3.734 in (94.84 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 4.012 in (101.9 mm). In service, this square-cut ring resists the spiral failure that affects round rings on long reciprocating strokes.

The material holds up against many alcohols, greases and lubricants, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) delivers low compression set under sustained load, strong abrasion and tear resistance. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving strong acids or polar solvents call for a different compound. The profile itself contributes simple lathe-cut manufacture at low tooling cost and a rectangular section that will not roll in the groove. 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 agricultural equipment, construction equipment, and hydraulic and pneumatic systems.

This item is sold individually under part number SH70240. Unit weight is approximately 3.4941 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.