... 2 It is used for automatic welding of circular welding seam in barrel and axis,such as transmission shah,axle, ... tank,tube union,flange,muffler,air reservoir,air compressor,etc.Welder is pneumatic controlled and weldment is on the support rollers ... mechanical major for the safe operation,reliable quality,smoothly pretty seam and substantially increased work efficiency.Adapting weldor:argon-arc welding ...