Spiral welding requirements specification
Date:2018-02-05 View:881 Tag:LSAW,LSAW Steel Pipe
Spiral steel pipe into the steel unit, multi-roll rolling strip gradually rolled up, and the formation of a gap with the open tube, squeeze roll to reduce the adjustment, weld gap control in 1 ~ 3mm, the weld flat.
1. If the gap is too large, resulting in reduced proximity effect, lack of eddy current, poor weld crystallization, indirect fusion or cracking bad.
2. The gap is too small, resulting in increased proximity effect, excessive welding heat, causing the weld to rupture; weld or extrusion, the formation of pit after rolling, affecting the weld surface quality.
After the tube is heated at both ends, the welding temperature is squeezed by the squeezing roller to form common metal particles which penetrate each other and crystallize, finally forming a solid weld. If the pipe extrusion pressure is too small, the formation of a small number of eutectics, stress reduction weld metal strength will produce cracking; if the pressure is too large, will make the molten metal is squeezed out of the weld, not only reduces the weld strength, But also produce a lot of internal and external burrs, and even cause welding defects such as seam.