The spiral spiral duct in Dongguan
is a spiral seam steel pipe
with strip steel coil as the raw material, which is often warm-kneaded and welded with active double-wire submerged arc welding technology.
(1) The raw materials are strip coil, welding wire, and flux. Before the investment, they must pass a severe physical and chemical test.
(2) With steel head and tail butt joint, single wire or double wire submerged arc welding is used. After coiling into steel pipe, active submerged arc welding repair welding is used.
(3) Before the spiral duct is formed, the strip is subjected to leveling, trimming, planing, surface clearing, conveying and pre-bending treatment.
(4) The electric contact pressure gauge is used to control the pressure of the oil cylinder at both ends of the conveyor to ensure the stable transportation of the strip.
(5) Use external control or internal control roll forming.
(6) Welding seam vacancy control equipment is used to ensure that the welding seam vacancy meets the demand for strong welding. The pipe diameter, misalignment and weld vacancy are all severely controlled.
(7) Both internal and external welding are performed by single- or double-wire submerged arc welding using the Lincoln welding machine in the United States, and then a stable welding standard is obtained.
(8) After welding, the welded seams are inspected online and continuously by an ultrasonic active wound instrument, which guarantees the non-destructive testing cage coverage rate of 100% spiral welds. If there are shortcomings, take the initiative to call the police and spray the symbols, and the production workers can adjust the process parameters at any time to eliminate the shortcomings in real time.
(9) Use air plasma cutting machine to cut the steel pipe into single pieces.
(10) After cutting into a single steel pipe, each batch of steel pipes must be subjected to severe first inspection criteria to check the mechanical properties of the weld, chemical composition, fusion scene, surface quality of the steel pipe and non-destructive testing of the steel pipe to ensure bundled pipes After the craftsmanship is qualified, it is officially transferred to production.
(11) The parts with consecutive sonic flaw detection marks on the welding seam of Dongguan spiral duct
are reviewed by manual ultrasonic and X-rays. If a shortcoming is indeed found, after the process is repaired, the nondestructive test is performed again until the shortcoming is recognized Eliminate.
(12) The address tube of the butt-welded strip weld and the T-shaped joint with the spiral weld are all checked through the process of X-ray television or filming.
(13) Each steel pipe undergoes a hydrostatic pressure test, and the radial pressure is selected. The test The test pressure and time are severely controlled by the steel pipe hydraulic pressure testing equipment. Quiz test parameters actively print records