Large Diameter Piling Structural Steel Pipe

Large diameter piling structural steel pipe is more than 1000 mm diameter steel pipe, large diameter seamless steel tube is made from solid tube ingot or the perforation capillary, then through hot rolling and cold rolling or cold dial. Large-diameter coating steel pipe is in the high frequency welded pipe of large diameter spiral welded pipe and coating on the basis of plastic, the most great mouth diameter of 1200 mm, according to the needs of the different coating of polyvinyl chloride (PVC), polyethylene (PE), epoxy resin (EPOZY), and other various plastic coating performance, good adhesion and corrosion resistance is strong, can resist the corrosion of strong acid, strong alkali and other chemical, non-toxic, does not rust, wear resistance, impact resistance, resistance to permeability is strong, the pipe surface is smooth, does not adhere to any material, can reduce the transmission of resistance, improve the efficiency of traffic and transportation, reduce the pressure loss. Coating without solvent, no leakage material, so that it can't be polluted by conveying medium, so as to ensure the purity of fluid and health, in 40 ℃ to + 80 ℃ range can be used cold heat cycles, not aging, not cracking, thus it can be used in cold zone and other harsh environment.

Pile structural steel pipe manufacturing method

(1) the raw material is steel strip coil, wire, flux. Have to pass strict physical and chemical inspection before investment.

(2) the strip head to tail docking, use single or double wire submerged arc welding, after rolled steel tube adopts automatic submerged arc welding repair welding.

(3) before shaping, strip after flattening, cutting edge, edge planing, transmission and cleaning the surface to the flanging process.

 (4) on both sides of the electric contact pressure gauge control conveyor under the pressure of oil cylinder pressure, ensure the smooth delivery of strip steel.

(5) the use of external control or internal control roll forming.

(6) the weld gap control device to ensure that meet the requirements of welding seam clearance, pipe diameter, and quantity of the wrong side of weld gap are tightly controlled.

(7) welding and welding are used within 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, ensure the spiral weld nondestructive testing coverage of 100%. If there are defects, automatic alarm and spray tags, production workers to adjust process parameters, in a timely manner to eliminate defects.

(9) by air plasma cutting machine to cut the steel tube into single.

Cut into single pole (10), after each batch of mild steel pipe in the first three root must carry on the strict inspection system, check the weld mechanical properties, chemical composition, amalgamation, steel tube surface quality and the nondestructive flaw detection, ensure that qualified pipe process, can be formally put into production.

(11) have continuous acoustic detection of weld mark parts, 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 d joint in the tube, all pass X-ray films and television inspection.

(13) each carbon 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. The parameters automatically printed out.

(14) pipe end machining, make the end verticality, slope Angle and the blunt edge to get accurate control.