How to choose submerged arc steel pipe

1. For pipelines with high peak shaving requirements, due to the uneven gas consumption of users, frequent  fluctuations in pipeline pressure, and great alternating stress on the steel pipe, the existing defects in the pipe  will expand under the alternating stress. For spiral welded steel pipes with many welds and a high probability of  defects, the operation of the pipeline will not be guaranteed.

2. The pipeline passes through the seismic fault zone or passes through the local high-intensity earthquake area. Due  to the frequent geological activities in these sections, the pipeline will generate longitudinal or axial alternating  stress. There are many spiral welds, and the probability of defects is higher than that of submerged arc steel pipes.  Under the action of long-term stress, the probability of accidents of spiral welded steel pipes is much higher than  that of submerged arc steel pipes. Therefore, submerged arc steel pipes should be used in this area.

3. Submerged arc steel pipes should be used for pipes with high requirements for internal and external anti-corrosion  layers. Spiral submerged arc welded steel pipe has many weld passes, and the residual height of the weld is generally  higher than that of submerged arc steel pipe. When the steel pipe is internally and externally anti-corrosion, the  combination of anti-corrosion material and bare pipe is not as close as that of submerged arc steel pipe, and the  anti-corrosion effect is not submerged arc. Steel pipe is good.

4. For important crossing projects, submerged arc steel pipes should be used. Since the maintenance and management in  the future is more difficult than the general line section, the use of submerged arc steel pipes with high  performance is particularly important.

5. For the weak links of the pipeline, such as hot simmering elbow pipes, submerged arc steel pipes should be used.  Due to the change of direction, the internal and external force of the hot simmering elbow is larger than that of the  straight pipe section of the general line. Due to the influence of various factors during the simmering process, its  stress is not easy to eliminate, and it is a relatively weak link in the long-distance pipeline. , the use of submerged arc steel pipes with good comprehensive performance can make up for these deficiencies.