Ring-joint gaskets are made in metallic materials.
The demands made on dimensional accuracy and the quality of the surface finish are therefore high, both for the gasket and the facing of the flange.
The two types of ring -joint gaskets differ as follows:
1. In the case of the ball-shaped ring-joint gasket, the ball-shaped surface of the gasket is pressed against the even, conical surface of the groove face during assembly.
2. In the case of the oval-shaped ring-joint gasket, the convex-shaped surface of the gasket forms a seal against the conical surface of the groove face.
The gasket stress increases or decreases proportionally to any changes in the bolting force.
Ring-joint gaskets according to API and ANSI standards are used mainly in the petrochemical industry and in refineries as a reliable sealing system. Soft iron self-regulating discs can be supplied for use in case of damaged groove faces. Other designs are available on request.