Metal spiral wound gaskets are currently the commonly used sealing gaskets and possess the best resilience among semi-metal sealing gaskets. They are made by alternately winding V-shaped or W-shaped thin steel strips with various fillers, capable of withstanding heat, high pressure, and meeting combined standard applications under low temperatures or in vacuum pumps. By altering the material composition of the gaskets, various chemical corrosion issues against the gaskets can be addressed. Their structural density can be tailored to meet different clamping force requirements. To enhance the main body and precise positioning, metal spiral wound gaskets are equipped with reinforcing rings and external locating rings made of metallic materials. The use of inner and outer steel rings allows for greater clamping force, and there are low requirements for the surface accuracy of the flange face in contact with the gasket.
Metal spiral wound gaskets with excellent resilience can automatically adjust to the working pressure, thermal cycles, and vibrations of piping systems. They are particularly suitable for places with uneven loads, easily loosened joint forces, regularly changing temperatures and working pressures, and where there are impacts or vibrations. They serve as rotating sealing elements at the flange connections of valves, pumps, heat exchangers, towers, handholes, manholes, etc., and are widely used in units such as petrochemicals, machinery and equipment, power engineering, metallurgical industry, shipbuilding, pharmaceuticals, nuclear energy, and aerospace.
In terms of flange gasket design, to facilitate installation, depending on the gasket's specifications and dimensions, 2 to 8 locating strips are welded onto the gasket off-site, allowing the locating strips to clip into the flange holes, preventing the gasket from moving or falling during installation, and saving auxiliary materials and construction time.
Generally, they are classified into the following types:
Metal spiral wound gaskets are made by alternately winding high-quality SUS304, SUS316 ("V"-shaped or "W"-shaped metal strips and other alloy products) with soft materials such as high-purity graphite, asbestos, polytetrafluoroethylene, alumina silicate fibers, etc., and fixing the metal strips in place at the beginning and end using welding techniques.
