Straight seam steel pipe is a tubular steel material formed by bending steel plate or strip and then welding to form a longitudinal seam. It gets its name from the straight shape of the weld seam. Compared to seamless steel pipe, it offers cost and production efficiency advantages under medium and low-pressure conditions. It is widely used in municipal engineering, water supply and drainage, and low-pressure oil and gas transportation, making it a highly cost-effective pipe choice for industrial and infrastructure construction.

The core production process focuses on "efficient forming and welding quality." The main process is as follows: hot-rolled or cold-rolled steel strip is first rolled into round or rectangular billets using a forming machine. The longitudinal seams are then welded using processes such as submerged arc welding and high-frequency welding to ensure the weld strength meets the required standards. Sizing, straightening, and non-destructive testing (such as X-ray inspection) are then performed to remove weld defects and calibrate the dimensions. Some straight seam steel pipes used for corrosion protection are also treated with internal and external coatings to enhance corrosion resistance. High-frequency welded straight seam steel pipes offer high production efficiency and are suitable for mass production of small and medium-diameter pipes. Submerged arc welded straight seam steel pipes offer superior weld quality and are suitable for large-diameter, thick-walled pipes.

Straight seam steel pipes have three key advantages: First, they offer lower costs. Continuous production using steel strips results in high raw material utilization, resulting in manufacturing costs 20%-30% lower than seamless steel pipes of the same specification. Second, they offer high production efficiency, enabling continuous assembly line production, with daily output reaching 3-5 times that of seamless steel pipes, enabling rapid fulfillment of large-scale project demands. Third, they offer a wide range of adaptability, enabling the production of pipes with diameters ranging from 15mm to 3000mm and wall thicknesses from 1mm to 20mm. They can also be manufactured in various cross-sections, such as square and rectangular, to meet the structural and transportation requirements of diverse projects. In practical applications, it is the "main pipe material" for municipal water supply and drainage, with large-diameter submerged arc welded straight seam steel pipe used in urban main water pipeline networks. High-frequency welded straight seam steel pipe is an "economical choice" for low-pressure oil and gas transportation, used in oilfield gathering and transportation networks and city gas medium-pressure pipelines. It is also a "foundational component" for steel structure engineering, with square and rectangular straight seam steel pipe used in structural components such as factory columns and bridge guardrails. With advancements in welding technology, the weld strength and corrosion resistance of straight seam steel pipe continue to improve, further expanding its application in medium- and high-pressure applications.