Production Technology of Spiral Steel Tube

Spiral pipe supplier china to introduce you: spiral steel pipe production process is simple, high production efficiency, low cost, rapid development. The strength of spiral steel pipes is generally higher than that of straight-seam welded pipes. It is possible to produce welded pipes with larger diameters from narrow blanks and to produce welded pipes with different diameters from blanks of the same width. But compared with the straight pipe of the same length, the length of the weld is increased by 30-100%, and the production speed is lower.

Spiral steel pipes are widely used. Spiral steel pipes are used in the chemical industry, power industry, agricultural irrigation, water engineering, petrochemical industry, and urban construction.

For liquid transportation: water supply and drainage. For gas transportation: coal gas, steam, liquefaction. For structural use: as a pile driving pipe, as a bridge; for wharf, road, building structure, etc.

Large diameter spiral steel pipe production process: the spiral seam steel pipe is made of steel coiled plate as the raw material, often hot extruded, welded by the automatic double-wire double-sided submerged arc welding process.

Large Diameter Spiral Steel Pipe 

(1) The raw materials are strip coil, welding wire, and flux. Before input, it must undergo strict physical and chemical tests.

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

(3) Before forming, the strip 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.

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

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

(7) Both internal welding and external welding use 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 an online continuous ultrasonic auto-injury instrument, which guarantees 100% coverage of non-destructive testing of spiral welds. 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) Use an air plasma cutting machine 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 reviewed by manual ultrasound and X-ray. If there are any defects, after a repair, they are subjected to 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-type joints intersecting with spiral welds are all inspected by X-ray TV or filming.

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

(14) The mechanical processing of the pipe end enables the verticality of the end face, the bevel angle and the blunt edge to be accurately controlled.