Part number H5.7X439.3 is a black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 439.3 mm (17.295 in), a cross section of 5.7 mm (0.224 in), and an outside diameter of 450.7 mm (17.74 in). An o-ring compresses into its gland to block fluid or gas migration across a joint. This item is further identified as Metric O-RING, JIS G440.
Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, reliable performance in both static and dynamic service. Expect good resistance to many alcohols, hydraulic fluids, and water. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Applications involving strong acids or ozone and direct sunlight call for a different compound.
It sees regular use in fluid power, general industrial maintenance, and hydraulic and pneumatic systems.
Reference part number H5.7X439.3 when ordering; the item is sold individually. Review your operating media and conditions against this specification before installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
description 5.7MM CS X 439.3MM ID BLACK BUNA 70D
uf_description2 METRIC O-RING, JIS G440
Actual_OD 450.7 mm (17.74 inch)
Actual_CS 5.7 mm (0.224 inch)
Actual_ID 439.3 mm (17.295 inch)
ProductCode Description O-Rings - Metric - Commodity