Ordered as SV70366, this is an AS568-366 black Viton® (FKM) 70 Shore A Square-Cut Ring supplied with an inside diameter of 7.225 in (183.52 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 7.645 in (194.18 mm). The square-cut ring resists the spiral failure that affects round rings on long reciprocating strokes.
Viton® (FKM) is specified here for very low compression set at elevated temperature and long service life in hot, chemically aggressive environments. This material stands up to aromatic hydrocarbons, aggressive chemicals, and petroleum oils and fuels. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). Applications involving low-molecular-weight organic acids or ketones and esters call for a different compound. The profile itself contributes a rectangular section that will not roll in the groove and greater resistance to extrusion than a round section of the same size. 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 fuel systems, high-temperature process equipment, and semiconductor equipment.
This item is sold individually under part number SV70366. Nominal inside diameter is listed as 7 1/4 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 568-366 FKM 75 SQUARE CUT RINGS
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 7.225 inch (183.52 mm)
Actual_OD 7.645 inch (194.18 mm)
ProductCode Description O-Rings - Square/Quad - Commodity