... .surface machining 3.strong making ability 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 ... ,304, 316 ,316L,inconel,monel graphite, ptfe, asbestos,non-asbestosStandard: ASME,ASNI,JIS, JPI, ISO, DN spiral wound gasket with inner ring and outer ring