... spiral wound gasket with inner ring and outer ring Spiral wound gasket with inner ring/centering ringThe spiral wound gasket is made of intercalarted V or W type formed steel ... the flange sealing surface.It is widly used in power plant, aviation,petrochemical,and valve industry,etc ... Ring material: CS plated zinc, stainless steel as ss304 3316,AS31803, alloy, and so on.Spiral material:A3 ,OCr13, 1Cr13, ...