Ordered as H4X190, this is a black Buna-N (Nitrile) 70 Shore A O-Ring with an inside diameter of 190 mm (7.48 in), a cross section of 4 mm (0.157 in), and an outside diameter of 198 mm (7.8 in). The o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.
As a material, Buna-N (Nitrile) delivers low compression set under sustained load, strong abrasion and tear resistance. It resists propane and butane, greases and lubricants, and petroleum-based oils. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving ketones or polar solvents call for a different compound.
You will find this material specified across fluid power, hydraulic and pneumatic systems, and automotive.
Reference part number H4X190 when ordering; the item is sold individually. Unit weight is approximately 9.2813 g. Review your operating media and conditions against this specification before installation. 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 4MM CS X 190MM ID BLACK BUNA 70D
uf_description2 METRIC O-RING
Actual_OD 198 mm (7.8 inch)
Actual_CS 4 mm (0.157 inch)
Actual_ID 190 mm (7.48 inch)
ProductCode Description O-Rings - Metric - Commodity