Large diameter water projects often need pipe sections with high flow capacity and workable production cost. Spiral welded pipe is used in many water supply, drainage, sewage treatment, irrigation, and municipal construction projects. The reference material explains that large diameter spiral pipe is usually above 1 meter in diameter, and a DN2500 pipe may have an actual outside diameter between 2500 and 2520 mm. Wall thickness can range from 8 mm to 25 mm or thicker.
The manufacturing route starts with steel coil. The strip is leveled, trimmed, and formed by rollers, and the weld gap is controlled before welding. Double-wire, double-sided submerged arc welding helps secure the seam. For large pipe, weld inspection matters because a long seam runs through every pipe section. Online ultrasonic testing and pressure testing can be included according to the project.
For a water line, the purchaser should confirm inside diameter, wall thickness, length, steel material, coating need, and end form. Some lines need only transport strength, while others require anti-corrosion coating or inner protection. If the pipe will be used in a buried route, soil condition and joint treatment should also be considered before final production.
