Production process of spiral pipe
(1) raw materials that are coil, wire, flux. In the investment before going through 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) the use of 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) the use of external control or internal control roll forming.
(6) the use of 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 an on-line continuous ultrasonic automatic injury inspection to ensure a 100% spiral weld non-destructive testing coverage. If there is a defect, automatic alarm and spray mark, the production workers at any time to adjust the process parameters, the timely elimination of defects
(9) the use of air plasma cutting machine to cut a single pipe.
(10) cut into a single steel pipe, each batch of steel pipe must be 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 the pipe process qualified After the formal 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 eliminated.
(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 pipe through the hydrostatic test, the pressure using radial seal. Test pressure and time by the steel pipe hydraulic microcomputer detection device strictly controlled. Test parameters are automatically printed.
(14) pipe end machining, so that the vertical face, bevel angle and blunt edge to be accurately controlled