The straight seam steel pipe is a steel pipe whose weld is longitudinally parallel to the steel pipe. It is generally divided into metric electric welding steel pipe, electric welding thin-wall pipe, transformer cooling oil pipe, etc. The production process of longitudinal welded pipe is simple, the production efficiency is high, the cost is low, and the development is fast. The strength of spiral welded pipe is generally higher than that of straight seam welded pipe. It can be used to produce welded pipe with larger pipe diameter with narrower blank, and can also be used to produce welded pipe with different pipe diameter with the same width blank. However, compared with the straight seam pipe with the same length, the weld length increases by 30~100%, and the production speed is low.
When selecting raw materials, pay attention to the following:
1. According to the quality requirements of the straight seam steel pipes produced, reasonably select the steel grades, specifications, allowable deviations and production methods of the required raw materials;
2. The raw material of straight seam steel pipe has no internal and external surface defects;
3. Straight seam steel pipes shall be packed neatly and firmly without loose coils and tower shapes;
4. The steel number, heat number and batch number shall be distinguished for the strip steel of the same specification of straight seam steel pipe.
