H90M3.5X31.7 is a black Buna-N (Nitrile) 90 Shore A O-Ring measuring an inside diameter of 31.7 mm (1.248 in), a cross section of 3.5 mm (0.138 in), and an outside diameter of 38.7 mm (1.52 in). In service, this o-ring creates a positive seal at flange, piston and rod interfaces without added hardware. This item is further identified as Metric O-RING, JIS P32.
As a material, Buna-N (Nitrile) is widely chosen for strong abrasion and tear resistance, reliable performance in both static and dynamic service. Expect good resistance to many alcohols, water, and greases and lubricants. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in ketones or strong acids.
It sees regular use in automotive, hydraulic and pneumatic systems, and fluid power.
Order part number H90M3.5X31.7, sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. For a size or compound outside the standard catalog, APG can quote from a print or sample.
Description 3.5MM CS X 31.7MM ID BLACK BUNA 90D
Actual Outside Diameter 38.7 mm (1.52 inch)
Actual Cross Section 3.5 mm (0.138 inch)
Actual Inside Diameter 31.7 mm (1.248 inch)
Measurement System Metric
Product Category O-Rings - Metric - Commodity