Difference between ssaw steel pipe and lsaw steel pipe
Metallurgical properties of raw materials
Straight seam submerged arc welding tube is made of steel, but spiral submerged arc welding steel pipe production is usd hot rolled steel coil strip. The hot strip rolling process with a series of advantages, has a metallurgical process for production of high-quality line pipe capacity.
From the welding process, spiral steel pipe welding method is the same as lsaw steel pipe, but the straight seam submerged arc welding tube inevitably will be a lot of T-weld, so the probability of presence of welding defects also greatly improved, and T-welds welding residual stress weld metal are often in a three dimensional stress state, increasing the possibility of cracks. According to the submerged arc welding process requirements, each weld should have the arc at the extinction,but each steel pipe is unable to meet the conditions in welding girth,which may be at the extinction more welding defects.
Difference between seamless steel pipe and ordinary steel pipe
Ordinary steel pipe, such as water pipes, is generally flat plate by bending and welded together after that you can find a seam in the above; and the seam of large diameter spiral weld is generally thicker.
Seamless steel pipe is generally through an annular slit molten state and then by stretching out the backlog of processing molding process, so there is no seam. In performance, especially compared with ordinary steel has greatly improved the bearing capacity, it is often being used for high-voltage equipment.
Hydraulic equipment such as piping connections. Ordinary steel weld parts of its weaknesses, weld quality is also a major factor in its overall performance impact. People who lived in the north generally have had water pipes or heating pipes burst in the winter cold experience explosive place are generally weld not seamless steel pipe.
Post time: Oct-30-2019