An improved, durable seal of folded seam connections is achieved by a flange like {HEAD ~ double fold} which is arranged at a first pipe end and which is surrounded on {TAIL ~ the outside} at least in part with positive locking and with a continuous metal seal, by a second double fold at the second pipe end 
An improved , durable seal of folded seam connections is achieved by a flange like { HEAD ~ double fold } which is arranged at a first pipe end and which is surrounded on { TAIL ~ the outside } at least in part with positive locking and with a continuous metal seal , by a second double fold at the second pipe end
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH