A washer is a component placed between a fastener and a nut; it typically takes the form of a flat metal ring.
Non-metallic gaskets are gaskets manufactured from non-metallic materials such as asbestos, rubber, synthetic resins, or polytetrafluoroethylene (PTFE). A non-metallic jacketed gasket is a non-metallic gasket encased in an outer layer of material such as synthetic resin.
Semi-metallic gaskets are gaskets composed of both metallic and non-metallic materials-examples include spiral-wound gaskets and metal-jacketed gaskets.
A spiral-wound gasket is a gasket formed by spirally winding a metal strip (typically featuring a V-shaped or W-shaped cross-section) interleaved with a non-metallic strip. An inner ring is a metal ring positioned within the inner circumference of a spiral-wound gasket, while an outer ring is a metal ring positioned around the outer circumference of the gasket.
Metal gaskets are gaskets manufactured from metals such as steel, aluminum, copper, nickel, or Monel alloy.
Specifically, a spiral-wound gasket refers to a ring-shaped gasket created by spirally winding a metal strip (typically a V-shaped steel strip) together with a non-metallic strip in an alternating pattern. Due to their excellent resilience, these gaskets are widely utilized in flange sealing assemblies across industries such as petrochemicals, general chemicals, and power generation. Depending on the specific application site, steel rings may be added to the inner or outer layers of the gasket to facilitate positioning or provide structural reinforcement.
