Ring-joint gaskets are primarily used in refineries and the petrochemical industry and are a purely metallic sealing body and belongs to the category of static gaskets. The sealing surface is slightly curved. It achieves a sealing effect due to the line contact that occurs during compression between the gasket body and the flange. This requires higher manufacturing qualities, such as lower roughness, compared to a sealing point consisting of a flat gasket and a smooth flange pair. A flat gasket achieves its sealing effect due to the plastic deformation of the gasket body and the resulting snug fit to the flange surface, which greatly reduces leakage paths in the gasket and between the gasket and flange surfaces.