568-252 BUNA 70 SQUARE CUT RINGS

Part number SH70252 is an AS568-252 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring measuring an inside diameter of 5.234 in (132.94 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.512 in (140 mm). A square-cut ring resists the spiral failure that affects round rings on long reciprocating strokes.

As a material, Buna-N (Nitrile) is known for the most widely specified general-purpose sealing elastomer and low compression set under sustained load. It resists propane and butane, greases and lubricants, and many alcohols. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). It should not be specified for service in automotive brake fluid or polar solvents. The profile itself contributes a rectangular section that will not roll in the groove 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.

Maintenance and OEM teams specify it across automotive, fluid power, and hydraulic and pneumatic systems.

Reference part number SH70252 when ordering; the item is sold individually. Unit weight is approximately 4.8496 g and nominal inside diameter is listed as 5 1/4 inch. Review your operating media and conditions against this specification before installation.