... ,pump,thermal exchange,auto vent-pipe, hole of flange and etc Spiral wound gasket:static sealing element of pipe, valve,pump,thermal ... tape, both its start point and end point are tack welded.3) Types: a) R type: spiral winding only b) IR type ... ring c) CG type: spiral winding with outer guide d) CGI type: spiral winding with outer guide and inner ring.4)material: metal ...