Description of Welding Flatness in Seamless Pipe

Seamless steel pipes have hollow cross-sections and are widely used as pipes for transporting fluids, such as pipes for transporting oil, natural gas, gas, water and certain solid materials. Compared with welded steel tubes, steel pipes have better mechanical properties when they have the same flexural and torsional strength.

Seamless pipes have strict requirements on cavity cleanliness and wall thickness dimensional tolerances. However, during the whole process of electric welding, due to the action of molten metal material, the thickness of the pipe at the weld will increase, and the inside and outside of the weld will be uneven. This will lead to increased energy consumption of the conveyor, at which point internal welding ground leveling techniques must be applied. Next, the production process of seamless pipes - internal welding and leveling will be introduced. Internal welding leveling is to use professional equipment to carry out multi-pass cold rolling on the welding seam, and then flatten the welding seam so that the surface of the inner and outer welding seams is smooth and free of delamination. The internal welding correction equipment for welded steel pipe is a kind of equipment with built-in mandrel and roller to reverse weld the pipe.

It can complete the "seamless splicing" of seamless pipes according to the overturning frequency and compressive strength. After understanding the technical characteristics of the machinery and equipment, let's take a look at the production process of the internal welding ground. After the internal welding precision rolls out with the leveling roller, the cross-section of the pipe becomes a horizontal ellipse, and the journal is stuck in the pipe and follows the pipe. After the vertical mixing cold rolling, the section of the pipe becomes circular. When the sound card frame returns, the journal is separated from the pipe and pulled back to the proper position by the cylinder, and then the secondary cold rolling cycle system is realized. After continuous extrusion, the lumen of the tube will become smoother and smoother.

The seamless pipe with internal welding correction technology is not easy to leave chemical substances on the inner wall, preventing the accumulation of liquid or corrosive chemical substances caused by welding; it is easy to clean and can avoid bacterial growth; the inner cavity has excellent corrosion resistance. In addition, especially when the pipes are used in the liquid and food industries, the inside of the pipes must be parallel so that the liquid does not cause blockages in the pipes. At this stage, the application range of this type of internal welding straightening technology is between diameter 12-219. Another thing to note is that seamless pipes of the same specification are equipped with a set of leveling rollers and vertical rollers, while pipes of the same specification but with different wall thicknesses are equipped with different journals.

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