568-178 FKM 75 SQUARE CUT RINGS

SV70178 is an AS568-178 black Viton® (FKM) 70 Shore A Square-Cut Ring supplied with an inside diameter of 9.737 in (247.32 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 9.943 in (252.55 mm). In service, this square-cut ring resists the spiral failure that affects round rings on long reciprocating strokes.

This material stands up to engine and transmission fluids, chlorinated solvents, and many acids. That behavior comes from the compound itself: Viton® (FKM) is valued for excellent resistance to compression set and permeation, the industry benchmark where nitrile reaches its thermal limit. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in amines or ketones and esters. The profile itself contributes a flat contact band that spreads sealing load across a wider area 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.

Typical settings include aerospace, oil and gas, and chemical processing.

Order part number SV70178, sold individually. Nominal inside diameter is listed as 9 3/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application.