Spiral welded pipe (also called as SSAW steel pipe) is the steel pipe with spiral seam that use a strip coil as raw material, extrusion molding at ordinary temperature, welding at automatic double wire double-sided submerged arc process. Next, Prime Steel Pipe will share the detailed production process of spiral welded pipe for you.
(1) Raw materials are coil, wire, flux. Before the investment all of those must undergo a rigorous physical and chemical testing.
(2) Strip head and tail docking, the use of single or double wire submerged arc welding, rolled into steel pipe after the use of automatic submerged arc welding.
(3) Before forming, the strip through the leveling, cutting edge, planing edge, surface cleaning and delivery to the edge of the treatment.
(4) Use electrical contact pressure gauge on both sides of the conveyor to control the pressure of the cylinder to ensure the smooth delivery of the strip.
(5) Use external control or internal control roll forming.
(6) Use weld gap control device to ensure that the weld gap to meet the welding requirements, diameter, misalignment and weld gap are strictly controlled.
(7) Welding and external welding are used in the United States Lincoln welding machine for single or double wire submerged arc welding, in order to obtain a stable welding specifications.
(8) Welded welds are subjected to continuous ultrasonic automatic wounding inspection to ensure 100% of the spiral weld nondestructive testing coverage.If flawed, automatic alarm and spray marking, the production workers at any time to adjust the process parameters , The timely elimination of defects.
(9) Use air plasma cutting machine to cut a single pipe.
(10) Cut into a single steel pipe, the first batch of three steel pipe to carry out a strict first inspection system, check the weld mechanical properties, chemical composition, melting conditions, steel pipe surface quality and after nondestructive testing to ensure that pipe Qualified before they can be put into production.
(11) Where there is a continuous acoustic flaw mark on the weld, after manual ultrasonic and X-ray review, if there is a defect, after repair, again after the nondestructive test until the defect has been identified.
(12) The butt welds of the strip and the pipe of the dies which intersect with the spiral weld are all examined by X-ray or film.
(13) Each steel pipe is subjected to hydrostatic test, and the pressure is radially sealed, and the test pressure and time are strictly controlled by the steel pipe hydraulic microcomputer detection device. Test parameters are automatically recorded.
(14) Pipe end machining, so that the vertical face, bevel angle and blunt edge to be accurately controlled.