The Advancement and Superiority of Straight Seam Welded Pipe

In recent years, most oil and gas pipelines in the world require the use of straight seam welded pipes. Canada and other western developed countries improve the process of spiral welded pipe, such as pre-welding, precision welding, multi-wire welding and mechanical expansion, etc., are designed with reference to the technology of longitudinal submerged arc welded pipe, which reflects the advanced nature of longitudinal welded pipe control technology and superiority. Specifically:

From the perspective of being suitable for offshore oil and gas transportation, it is necessary to build straight seam welded pipes. At present, a considerable part of the world's oil and gas resources are buried in the ocean. From the perspective of future gas development, they are mainly buried in the ocean in the form of "combustible ice". It is currently recognized that the total energy of "combustible ice" is 2 to 3 times that of all coal, oil and gas, and the same is true in China. It will be the main energy source in the future.

  Recently, China is accelerating the pace of oil and gas in the East China Sea. With the development of oil extraction to the depths of the ocean, the submarine pipeline is crushed under the combined action of pressure, impact and bending force, which is the weak link of the spiral welded pipe. In order to improve the pipeline transportation capacity and make the submarine pipeline develop in the direction of thick wall, the submarine pipeline mostly adopts  the straight seam welded pipe.

From another point of view, due to the difficulty of butt welding of pipelines in the ocean, the ovality, alignment, groove protection and cross-section error of the steel pipe are required to be high, otherwise the operation efficiency will be seriously affected. Therefore, compared with the spiral welded pipe, the dimensional accuracy of the straight seam welded pipe is higher, and the repair welding is easier. So from this aspect, the straight seam welded pipe is also the first

Coal slurry and ore slurry pipelines require straight seam welded pipes. Coal and mineral powder are transported in the "slurry" state in the upward direction. Since the welding seam in the spiral welded pipe is a spiral, the resistance to the coal slurry is large, and the pipeline needs a larger wall thickness, so straight seams tend to be used. Welded pipe.