Call Us at 713.356.3500


product image

Gasket Material

The gasket material should be selected to suit the service environment. The gasket material should be softer than the flanges in which the gasket is installed. The most popular ring joint materials with maximum hardness and identification mark are shown in the table below. For more highly specialized applications, ring joint gaskets can be machined from duplex stainless steels and other exotic materials such as Monel®, Inconel® Incoloy®, and Hastelloy®.

Hardness requirements and identification marks for ring gaskets
Material Maximum Hardness HRB Mark
Soft Iron 56 D-4
Carbon and low alloy steel 68 S-4
304 stainless steel 83 S304-4
316 stainless steel 83 S316-4
Nickel alloy UNS N08825 92 825-4
Other CRA materials *A UNS number-4
*a: Hardness shall meet manufacturer's written specification