Ordered as SH70026, this is an AS568-026 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring supplied with an inside diameter of 1.239 in (31.47 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.379 in (35.03 mm). The square-cut ring offers greater contact area against the gland wall than an equivalent o-ring.
As a material, Buna-N (Nitrile) delivers strong abrasion and tear resistance, low compression set under sustained load. The material holds up against propane and butane, water, and greases and lubricants. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Exposure to ketones or polar solvents will shorten service life. The profile itself contributes a flat contact band that spreads sealing load across a wider area 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.
It sees regular use in fluid power, automotive, and hydraulic and pneumatic systems.
Reference part number SH70026 when ordering; the item is sold individually. Unit weight is approximately 0.3646 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
description 568-026 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.07 inch (1.78 mm)
Actual_ID 1.239 inch (31.47 mm)
Actual_OD 1.379 inch (35.03 mm)
ProductCode Description O-Rings - Square/Quad - Commodity