Part number SH70342 is an AS568-342 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring supplied with an inside diameter of 3.6 in (91.44 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 4.02 in (102.11 mm). A square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.
Buna-N (Nitrile) is specified here for low compression set under sustained load, reliable performance in both static and dynamic service. Expect good resistance to hydraulic fluids, many alcohols, and propane and butane. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ozone and direct sunlight or ketones are present. The profile itself contributes a rectangular section that will not roll in the groove 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.
You will find this material specified across hydraulic and pneumatic systems, construction equipment, and automotive.
SH70342 ships individually. Unit weight is approximately 7.9135 g. Check the compound against your process media, pressure and temperature before committing to a design. 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 568-342 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 3.6 inch (91.44 mm)
Actual_OD 4.02 inch (102.11 mm)
ProductCode Description O-Rings - Square/Quad - Commodity