DN2220Spiral steel pipe:
(1) raw materials that coil, wire, flux. In the input before going through rigorous physical and chemical tests. In this case,
(2) head-to-tail docking, the use of single-wire or double-wire submerged arc welding, rolled into steel after the adoption of automatic submerged arc welding. In this case,
(3) Before forming, the strip after the flattening, cutting edge, planing, surface cleaning and transportation to the bending treatment. In this case,
(4) spiral pipe pressure gauge using electrical contacts control the pressure on both sides of the conveyor cylinder pressure to ensure the smooth transport of strip. In this case,
(5) the use of external control or internal control roller molding. In this case,
(6) the use of weld gap control device to ensure that the welding gap to meet the welding requirements, diameter, the wrong amount of margin and weld gap are strictly controlled. In this case,
(7) spiral steel pipe welding and outer welding are used Lincoln US welding machine for single wire or double wire submerged arc welding, in order to obtain a stable welding specification. In this case,
(8) Welded welds have been through the line of continuous automatic ultrasonic inspection instrument to ensure that the 100% of the spiral weld nondestructive testing coverage. If there are defects, automatic alarm and spray marking, production workers at any time to adjust the process parameters, the timely elimination of defects. In this case,
(9) the use of air plasma cutting machine will cut into a single pipe. In this case,
(10) spiral pipe plant cut into a single pipe, each batch of steel pipe must be strictly the first inspection system to check the mechanical properties of welds, chemical composition, fusion conditions, steel pipe surface quality and non-destructive testing to ensure that the system Tube process qualified, to be formally put into production. In this case,
(11) The location of the weld on the continuous acoustic flaw detection mark, after manual ultrasonic and X-ray review, if there are defects, after repair, again after non-destructive testing until the defect has been confirmed to eliminate. In this case,
(12) The welds of the strip butt welds and the pipes of the d-type joints intersecting the spiral welds are all examined by X-ray television or film inspection. In this case,
(13) Each pipe is subjected to a hydrostatic test, and the pressure is radially sealed. Test pressure and time by the computer control of water pressure microcomputer control. Test parameters automatically print records. In this case,
(14) pipe end machining, the end of the vertical, groove angle and blunt edge be accurately controlled.
