Production steps of spiral steel pipe

Do you know the production steps of spiral Steel Pipe? Below, I will introduce it to you in detail.

(1) Various inspections of raw materials are carried out. Raw materials generally refer to strip coils, welding wires, fluxes, etc. Strict physical and chemical inspections should be carried out before investing to ensure quality.

(2) The head and tail of the strip are butted by single-wire or double-wire submerged arc welding, and automatic submerged arc welding is used for repair welding after rolling into a steel pipe.

(3) Process treatment. Before forming, the required steel is straightened, sheared, planed, surface cleaned, transported and bent.

(4) The electric voltmeter is used to control the pressure of the depressing cylinders on both sides of the conveyor to ensure the smooth transportation of the strip steel.

(5) Adopt external control or internal control roll forming.

(6) The welding seam gap control device is adopted to ensure that the welding seam gap meets the welding requirements, and the pipe diameter, the amount of misalignment and the welding seam gap are strictly controlled.

(7) The American Lincoln welding machine uses the American Lincoln welding machine to carry out single-wire or double-wire submerged arc welding to obtain stable welding specifications.

(8) The welding seam is inspected by the online continuous ultrasonic automatic damage instrument to ensure 100% non-destructive testing coverage of the spiral steel pipe. If there is a defect, it will automatically alarm and spray the mark. Production workers should adjust the process parameters at any time to eliminate defects in time.

(9) Cut the steel pipe into single pieces with an air plasma cutting machine.

(10) After cutting into a single steel pipe, the first three Steel Pipes of each batch should undergo a strict first inspection system to check the mechanical properties, chemical composition, dissolution status, surface quality of the steel pipe and non-destructive testing of the welds to ensure that the pipeline technology is qualified. to be officially put into production.

(11) The parts with continuous sonic flaw detection marks on the welds shall be re-examined by manual ultrasonic wave and X-ray. If there is any defect, the non-destructive inspection shall be carried out again after repair until it is confirmed that the defect has been eliminated.

(12) The pipeline where the strip butt weld and the T-joint intersecting with the spiral weld are inspected by X-ray television or filming.

(13) Each steel pipe undergoes a hydrostatic pressure test, and the pressure is radially sealed. The water pressure microcomputer detection device of the steel pipe strictly controls the test pressure and time. Automatically print and record test parameters.

(14) Machining the pipe end to accurately control the verticality, slope angle and blunt edge of the end face.

Usually, through the above 14 steps, the spiral steel pipe has been formed, but such a spiral steel pipe cannot be directly used, and the quality of the spiral steel pipe needs to be checked.