Double Sided S355J2H S275 S275JR S355JRH SAW Steel Pipe

Longitudinal submerged arc welded pipe (LSAW pipe for short). Longitudinal Submerged Arc Welding (LSAW) is a process of pressing (rolling) steel plate into the billet of die or forming machine, using single plate as raw material. Double-sided submerged arc welding is used to enlarge the diameter. The finished product has complete specifications, good weld toughness, good plasticity, uniformity, compactness, large diameter, thick wall, high pressure, low temperature and corrosion resistance.

The cold expansion diameter also has the effect of improving the straightness of lsaw steel pipe, especially the straightening effect on the smaller diameter straight seam submerged arc welded pipe.
After the cold expansion of the lsaw steel pipe, the diameter of the pipe body and the pipe end will increase by about one percent. The diameter, the roundness and the diameter difference between the two ends of the steel pipe are greatly improved, and the straightness of the steel pipe is also greatly improved. The length is reduced by about 0.5%, and the wall thickness is reduced by about 0.8%. In the development of the lsaw steel pipe process, these changes should be fully considered to determine the width, length and thickness of the pipe sheet and the outer diameter of the steel pipe before the diameter expansion, so as to avoid the geometrical dimension of the steel pipe after the expansion is not up to the final requirements.

Application of LSAW Steel Pipe. The pipes are primarily used as long-distance transportation pipeline for oil, gas, liquid coal, etc. ashore and offshore. And can also be applied as construction pipes on offshore platform, powerhouse, petrochemistry, and town construction, etc