Spiral Wound Metal Gasket Material: Metal tape + Expanded Graphite / PTFE Spiral wound metal gasket : Spiral wound gasket (basic type) is made by superposing, winding and welding V-type or W-type stainless steel tape and non-metallic filing. It is usually wound by stainless steel, 304,304L,316,316L,321,Ta Mon400, Inconel, asbestos (graphite, PTFE, mica, ceramic) tape used for special-purposed ...