Joints metal-ring-joint-facing

The gasket consists of a lens shaped ring of heat treated low alloy steel or some other metal. The ring should be softer than the flange face. Flardness of the conventional lens ring varies with the metal required for the service condition. This joint is ideal for pipe and tube applications. It can be used for small connections and can be used for pressure vessel closures but is better suited for piping applications. 

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