The difference between straight seam welded pipe and spiral welded pipe

1. Metallurgical properties of the material
The raw material of the spiral welded pipe is a hot-rolled coil, and the straight seam welded pipe is made of a steel plate socket. The weight of the alloy contained in the coil is less than that of the steel plate, and it is for this reason that the spiral welded pipe has higher weldability than the steel plate. in addition. The rolling direction of the coil has a certain helix angle, but the dry plate of the straight seam welded pipe is rolled in the direction perpendicular to the axis of the steel plate, so in comparison, the spiral welded pipe has better crack resistance.

2. Features of strength
The rotation angle of the spiral welded pipe weld is between 50-75 degrees, so the stress at the result of the weld is 60-85% of that of the straight welded pipe. Therefore, if the two are under the same working pressure, the pipe wall of the spiral welded pipe can be reduced for two types of welded pipes with the same diameter. Therefore, if the spiral welded pipe is blasted, its blasting port will not appear in the weld, and its safety is higher than that of the straight welded pipe.

3. Welding process comparison
In the welding process, the welding of the two is the same. However, if the straight seam welded pipe is welded, there may be a T-shaped weld, which is a major welding defect. The straight seam welded pipe of the T-shaped weld is also more likely to have cracks. In this regard, due to the different welding directions, the spiral welded pipe can avoid this situation well.

4. Field Solderability
The material of the steel pipe and the dimensional tolerance of the port fit determine the field weldability. Spiral welded pipes are produced in a stable and continuous process under the same working conditions, but straight seam welded pipes are different, and their production is carried out in sections. This is also a big difference between the two. The welding seam of the spiral welded pipe is evenly distributed and the pipe shape of the welded pipe is also very regular, so it is very good to ensure the welding accuracy of the field weldability along with the straight seam welded pipe.