Metal O ring. They are non self-tightening type, self-tightening type and inflatable type.
Metal o-rings seal mechanism similar to flat mat, rely on the deformation of the ring after preloaded back stretch, make the sealing surface produces a certain amount of stress. The material yield stress can make hollow ring surface, fill seal groove on theuneven, to keep the surface finish requirement. In a sealed lively media, also should be electroplated or spraying high ductility compensation materials.