1 Definition: welded steel pipe is also called welded pipe which is steel pipe formed by welding the curled steel plates or strip steel, with general fixed length of 6m.
2 Production process: raw material uncoiling – flattening – end cutting and welding – looping – molding – welding – internal/external removal of welding beads – precorrection – inductive heat treatment – sizing and straightening – eddy current testing – cutting – water pressure inspection – acid pickling – final inspection (strict control) – packing – delivery
3 Category:
Production methods:
a. Process – electric arc-welded pipes, resistance welded pipe (high frequency, low frequency), gas-welded pipes, furnace butt-welded pipes
b. Welding seam – straight welded pipes, spiral welded pipes
welded steel pipe