Knowledge of Spiral Wound Gasket (HY-industry technical centre)
Spiral wound gaskets are usually made of high-quality SUS304, SUS316 (“V”-shaped or “W”-shaped) metal belts and other alloy materials and graphite, asbestos, polytetrafluoroethylene, non-asbestos and other soft materials alternately overlapped and spirally wound. Fix the metal strips by spot welding at the beginning and at the end.
Spiral wound gaskets have the best resilience among semi-metallic gaskets. The structure density of spiral wound gaskets can be made according to different locking force requirements, and the inner and outer steel rings are used to control the maximum compression. Metal wound gaskets The surface accuracy of the flange sealing surface contacted by the sheet is not high.
Spiral wound gaskets are especially suitable for occasions where the load is uneven, the joining force is easy to relax, the temperature and pressure change periodically, and there is impact or vibration. Spiral wound gaskets are static sealing elements for flange connection processing such as valves, pumps, heat exchangers, towers, manholes, and hand holes.
Performance characteristics of spiral wound gaskets
Spiral wound gasket has good compression performance, good resilience, multi-channel sealing and certain self-tightening function. It is not sensitive to the surface defects of the flange pressing surface. It does not adhere to the flange sealing surface, which can partially eliminate pressure and temperature changes. And mechanical vibration; it can maintain its excellent sealing performance under various harsh conditions such as high temperature, low temperature, high vacuum, shock vibration and so on.
Flange connections of pipelines, valves, pressure vessels, condensers, heat exchangers, towers, manholes, hand holes, etc. in petroleum, chemical, metallurgical, electric power, shipbuilding, gas, nuclear energy, aerospace, textile, medicine, machinery and other industries Static sealing part.
Spiral wound gasket material selection
1. Basic winding metal tape
Use sus304, sus316L, sus321 and other cold-rolled steel strips with a thickness of 0.15mm~0.25mm, or they can be negotiated between the supplier and the buyer.
Metal belt is a pre-formed V-shaped or W-shaped narrow belt. The surface should be smooth and clean. There should be no roughness, cracks, scratches, pits, rust spots and other defects.
Hardness value of stainless steel HV≤200
following table is used to select the material of the inner ring and the winding metal belt: