Spiral steel pipe manufacturing process

Generally speaking, spiral steel pipes in one type of welded steel pipe in the pipe market, which are made by steel coil, extrusion forming under the normal temperature, and then undertake the manufacturing technology of double wire and double-faced submerged-arc welded in a mill. In the past, due to the method of manufacture, Spiral Welded pipe was relegated to low pressure and structural applications. With the development of the Submerged Arc Welding process, the production of large hot rolled coils of sufficient width and the development of dependable non-destructive testing methods, it is now possible to produce Spiral Weld pipe for high-pressure service.

Spiral steel pipe process
(1) Raw materials that refers to the steel strip coil, wire spiral steel pipe, flux. Have to pass strict physical and chemical inspection before investment.
(2) Strip head to tail docking, use single or double wire submerged arc welding, after rolled to steel tube, adopts automatic submerged arc welding for repair welding.
(3) Before forming, strip steel should go through the process of flattening, cutting edge, edge planing, transmission and surface cleaning, flanging process.
(4) The electric contact pressure gauge to control the cylinder under pressure of two side of conveyor to ensure the smooth delivery of strip steel.
(5) The use of external control or internal control roll forming.
(6) the control unit to ensure weld spiral pipe weld space meets the demand of welding; the pipe diameter, quantity of the wrong side and weld gap are tightly controlled.
(7) External or internal welding are used the United States Lincoln welding machine for single or double wire submerged arc welding, to obtain the stable welding specification.
(8) After welding, the weld passes the online continuous ultrasonic automatic meter check, to ensure the spiral weld nondestructive testing coverage of 100%. If there are defects, automatic alarm and spray tag, production workers to adjust process parameters, in a timely manner to eliminate defects.
(9) Using air plasma cutting machine to cut the steel tube into single.
(10) For most cold rolled steel pipes, every batch of steel pipe in the first three must carry on the strict inspection after cut into single, to check the weld mechanical properties, chemical composition and amalgamation. Steel tube surface quality and the nondestructive flaw detection to ensure that qualified pipe process and then can be formally put into production.
(11) There is a continuous acoustic detection on weld, after manual ultrasonic and X-ray check, if there are defects, after repair, again through the nondestructive inspection, until defects have been eliminated.
(12) Strip steel butt weld and fellowship with spiral weld “丁”joint in the tube, all pass X-ray films and television inspection.
(13) Each steel pipe after hydrostatic pressure test, radial sealing for the pressure. Test pressure and time are controlled strictly by steel pipe hydraulic microcomputer testing device.
(14) Pipe end machining to make the end vertical, and slope angle and the blunt edge to get accurate control.
During molding process of spiral welded steel pipe, steel plate has uniform deformation and light residual stress, thus the surface has no scratches. In the real life, we can often see many round steel pipe widely used for certain purposes around us. Spiral steel pipe has more flexible thicknesses and diameters, especially in making high-grade thick pipes with small or medium aperture, these techniques has incomparable advantages in satisfying your needs.

Spiral steel pipe is mainly used in public waterworks, petrochemical industry, chemical industry, electric power industry, agricultural irrigation and urban construction etc. As a professional steel pipe manufacturer in China, we are always committed to offering different types of steel pipe for your specific applications.