It is a kind of spiral steel pipe, which is made of steel rolling plate as raw material, often extruded and welded by active double wire submerged arc welding process.
(1) Raw materials are strip coil, welding wire and flux. We should pass strict physical and chemical examination before investment.
(2) Single wire or double wire submerged arc welding shall be adopted for butt joint of strip head and tail, and active submerged arc welding shall be adopted for repair welding after rolling steel pipe.
(3) Before forming, the strip steel shall be leveled, cut and planed, cleaned, transported and bent on the surface.
(4) The electric contact pressure gauge is used to control the pressure of the oil cylinder on both sides of the conveyor to ensure the smooth transportation of the strip steel.
(5) External control or internal control roll forming is selected.
(6) The gap control equipment is selected to ensure that the gap meets the welding requirements, and the pipe diameter, stagger amount and gap are strictly controlled.
(7) Lincoln Electric welding machine is selected for internal and external welding to conduct single wire or double wire submerged arc welding, so as to achieve stable welding standards.
(8) After welding, all the welds are checked by online continuous ultrasonic active damage instrument, which ensures 100% coverage of non-destructive testing of spiral welds. If there is any defect, alarm and spray the symbol actively, and the production workers can adjust the process parameters at any time according to this, so as to eliminate the defect in time.
(9) Select air plasma cutting machine to cut the steel pipe into single pieces.