Process of Producing Spiral Steel Pipe

Time：2020-08-13    View：1704

How to produce all kinds of spiral steel pipes from a piece of steel?  Today I will introduce to you all the steps in the production of spiral steel pipes.

 (1) Perform various inspections on raw materials.  Raw materials generally refer to strip coils, welding wire, flux, etc.  Before putting it in, it must undergo strict physical and chemical tests to ensure quality.

(2) The head and tail of the steel strip are butt jointed, using single-wire or double-wire submerged arc welding, and automatic submerged arc welding after welding.

(3) Process treatment.  Before forming, the required steel is leveled, trimmed, planed, surface cleaned and transported and pre-bent.

 (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 steel strip.  A

 (5) Rolling with external control or internal control.

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

 (7) Both internal and external welding are performed by American Lincoln electric welding machine for single-wire or double-wire submerged arc welding, so as to obtain stable welding specifications.

 (8) All welded seams are inspected by online continuous ultrasonic automatic flaw detector to ensure 100% coverage of non-destructive testing of spiral steel pipes.  If there are defects, it will automatically alarm and spray marks, and the production workers will adjust the process parameters at any time according to this, and eliminate the defects in time.

 (9) The air plasma cutting machine is used to cut the steel pipe into single pieces.

 (10) After cutting into a single steel pipe, each batch of three steel pipe heads must undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion state, surface quality of the steel pipe and non-destructive inspection to ensure the pipe making process  Only after being qualified can it be officially put into production.

 (11) The parts with continuous sonic flaw detection marks on the welding seam are manually re-examined by ultrasonic and X-ray. If there are defects, after repairing, they will undergo non-destructive inspection again until it is confirmed that the defects have been eliminated.

 (12) Tubes with butt-welded welds of steel strips and D-joints that intersect spiral welds are all inspected by X-ray television or filming.

 (13) Each steel pipe undergoes hydrostatic pressure test, and the pressure is sealed by radial.  The test pressure and time are strictly controlled by the steel pipe hydraulic microcomputer detection device.  Test parameters are automatically printed and recorded.

 (14) Mechanical processing of the pipe end, so that the verticality of the end face, the bevel angle and the blunt edge are accurately controlled.

 Usually, after the above 14 steps, a spiral steel pipe has been formed, but such spiral steel pipe cannot be directly sent to the market, and it is necessary to carry out work such as checking the quality of the spiral steel pipe and other aspects.  Introduction of Straight Seam Steel Pipes Straight seam steel pipes are steel pipes with welds parallel to the longitudinal direction of the steel pipe.  Usually divided into metric welded steel pipes, welded thin-walled pipes, transformer cooling oil pipes and so on.