Spiral steel pipe production process
Spiral steel pipe production process
Spiral steel pipe production process and storage skills
Spiral steel pipe is a spiral seam steel pipe made of strip steel coils as raw materials, often extruded and formed by automatic double-wire double-sided submerged arc welding. The main production process is as follows:
(1) Raw materials are strip steel coils, welding wires, and fluxes. Strict physical and chemical tests are required before investment.
(2) Butt joint of strip steel head and tail, using single wire or double wire submerged arc welding, after coiling into steel pipe, using automatic submerged arc welding repair welding.
(3) Before forming, the strip undergoes leveling, edge trimming, edge planing, surface cleaning and conveying and pre-bending treatment.
(4) The electric connection voltmeter is used to control the pressure of the cylinders on both sides of the conveyor to ensure the smooth conveying of the strip.
(5) Adopt 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 all strictly controlled.
(7) Both internal welding and external welding adopt American Lincoln electric welding machine for single-wire or double-wire submerged arc welding to obtain stable welding specifications.
(8) The welded seams are all inspected by the on-line continuous ultrasonic automatic flaw detector, which guarantees 100% nondestructive testing coverage of spiral welds. If there is a defect, it will automatically alarm and spray the mark, and the production workers can adjust the process parameters at any time to eliminate the defect in time.
(9) Use an air plasma cutting machine to cut the steel pipe into individual pieces.
(10) After cutting into single steel pipes, the first three steel pipes of each batch shall undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion status of the welds, the surface quality of the steel pipes and pass non-destructive inspections to ensure the pipe manufacturing process Only after it is qualified can it be officially put into production.
(11) The parts with continuous sonic flaw detection marks on the weld are re-examined by manual ultrasonic and X-ray. If there are defects, after repairing, they will go through non-destructive inspection again until the defects are confirmed.
(12) The pipes where the strip butt welds and the D-shaped joints intersecting the spiral welds are all inspected by X-ray television or filming.
(13) Each steel pipe undergoes hydrostatic pressure test, and the pressure adopts radial seal. The test pressure and time are strictly controlled by the steel pipe hydraulic microcomputer detection device. The test parameters are automatically printed and recorded.
(14) The pipe end is machined to accurately control the verticality of the end face, the bevel angle and the obtuse edge.
Spiral steel pipe storage skills:
The stable improvement of spiral steel pipe product quality is a strong guarantee for the company's economic benefit. Over the years, we have insisted on putting product quality in the first place, strengthening quality supervision and information feedback, and controlling hidden quality hazards in the process. The qualified rate of the products in the previous industrial product quality inspections in Tianjin is 100%. High-quality products have enabled our company to obtain a series of certificates such as APISPEC5L product certification issued by the American Petroleum Institute. "This is an important pass for sales staff to break through major customers and further expand the export market for products."
1) The site or warehouse for storing spiral steel pipe products should be located in a clean and well-drained place, away from factories and mines that produce harmful gases or dust. Weeds and all debris should be removed on the field, and the steel should be kept clean.
2) Do not stack them in the warehouse with materials that are corrosive to steel such as acid, alkali, salt, cement, etc. Different types of steel should be stacked separately to prevent confusion and contact corrosion.
3) Large section steel, rails, steel plates, large diameter spiral steel pipes, forgings, etc. can be stacked in the open air.
4) Small and medium-sized steel bars, wire rods, steel bars, medium-diameter steel pipes, steel wires and wire ropes, etc., can be stored in a well-ventilated material shed, but must be topped and bottomed.
5) Some small steels, thin steel plates, steel strips, silicon steel sheets, small-caliber or thin-wall spiral steel pipes, various cold-rolled and cold-drawn steels, and high-priced and easily corrosive metal products can be stored in storage.
