The quality of straight seam steel pipe products is not blown out. Let’s take a look at what is the product in the eye. Take Large diameter anti-corrosion longitudinally submerged arc welding pipe as an example: high production efficiency, low interest rate, fast and continuous production, and relatively simple process. . Civil construction, petrochemical, light industry and other departments have a wide range of uses. They are used to transport low-pressure fluids or to make various engineering components and light industrial products. The straight seam steel pipe is obtained by winding a long strip of steel strip of a certain specification into a circular tube by a high-frequency welding unit and welding the straight seam into a steel pipe. Straight seam high-frequency welded steel pipe production process Straight seam steel pipe is a high-frequency welding unit that winds a certain length of strip steel strip into a circular tube and welds the straight seam into a steel pipe.
The shape of the steel tube may be circular or square or irregular depending on the sizing rolling after welding. The information of welded steel pipe is mainly low carbon steel and low alloy steel or other steel. The production process of high-frequency welding of straight seam steel pipe is as follows: the steel at the edge of the weld is locally heated to the molten state, and the high-frequency welding of China Steel Pipe Information Port China Steel Pipe The high-frequency welding of the information port is based on the principle of electromagnetic induction and the skin effect, proximity effect and eddy current effect of the alternating charge in the conductor. Through the extrusion of the roller, the butt weld can achieve intergranular bonding, so as to achieve the purpose of weld welding. High-frequency welding is a kind of induction welding (or pressure contact welding) without weld filler, no welding splash, welding heat affected zone It is widely used in the production of steel pipes because of its narrow welding, beautiful welding and good mechanical properties.
Of course, the difference between the two is not limited to the above three points, but it is enough to show that there is still a big difference between straight seam steel pipe and thermal tension reducing steel pipe. On the basis of the straight seam welded pipe, the latter has carried out a series of new technologies such as internal and external burrs, integral heating, and deformation, which have made a qualitative leap, which can be widely used in the medium and high pressure field, and straight. Seam welded pipes can only be confined to water gas transportation in low pressure environments. Although some people are currently in a state of vague understanding of seamless steel tubes, heat-tension-reducing steel pipes, and straight-slot welded pipes, it is believed that with the passage of time, the proof of practice will correctly understand the thermal tension reduction steel pipe. This unique product makes it more and more important in the seamless steel pipe market, creating greater economic benefits for the society.
In the anti-corrosion construction process of oil and gas pipelines, the surface treatment of straight seam steel pipe is one of the key factors determining the service life of pipelines. It is the premise of whether the anti-corrosion layer and the straight seam steel pipe can be firmly combined. According to the research of professional institutions, the life of the anti-corrosion layer depends on the type of coating, coating quality and construction environment. The surface treatment of straight seam steel pipe affects the life of the anti-corrosion layer by about 50%. Therefore, it should be strictly in accordance with anti-corrosion. Layer specification on the requirements of the surface of straight seam steel pipe, continuously improve the surface treatment method of straight seam steel pipe.
Straight seam steel pipe removal methods mainly include the following:
1. Cleaning: Clean the surface of the steel with solvent and emulsion to remove oil, grease, dust, lubricant and similar organic matter, but it can not remove the rust, scale, flux, etc. on the surface of the steel, so it is only used in the defense operation. As an aid.
2, pickling: generally chemical and electrolytic two methods of pickling, pipeline anti-corrosion only chemical pickling, can remove oxide scale, rust, old coating, and sometimes can be used as sandblasting after rust removal. Although chemical cleaning can achieve a certain degree of cleanliness and roughness, its anchor pattern is shallow and it is easy to cause pollution to the surrounding environment.
3, tool derusting: mainly use wire brush and other tools to polish the surface of the steel, can remove loose oxide scale, rust, welding slag and so on. The rust removal of the hand tool can reach the Sa2 level, and the rust removal of the power tool can reach the Sa3 level. If the surface of the steel is adhered to the iron oxide scale, the rust removal effect of the tool is not ideal, and the anchor depth required for the anti-corrosion construction cannot be achieved.
4, spray derusting: jet derusting is driven by high-power motor to drive the high-speed rotation of the jet blades, so that the steel balls, steel sand, wire segments, minerals and other abrasives are sprayed on the surface of the straight seam steel pipe under the strong centrifugal force of the motor. Not only can the oxide, rust and dirt be completely removed, but the straight seam steel tube can achieve the required uniform roughness under the action of abrasive impact and friction.