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Inner welding flatness of seamless steel pipe

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.

Causes of unevenness during welding of seamless steel pipes
1. When the welding is generally circular, the viewing angle of the welding wire will change.
2. When the metal is melted, the vertical position of the seamless steel pipe will have an annoying tendency to develop, which will cause welding scars.
3. When the seamless steel pipe is welded vertically, there is a sound of water droplets inside, and then there will be uneven penetration.

The unevenness of the welding inside and outside will lead to an increase in the energy consumption of the conveyor. At this time, the internal welding ground leveling technology must be applied. That is, it can complete the "seamless splicing" of seamless pipes according to the overturning frequency and compressive strength. 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.



Advantages of Internal Weld Correction Technology
1. 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;
2. It is easy to clean and can avoid the growth of bacteria;
3. 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.

Know more about this product price, catalogue, mill test certificate,  please inquiry to: sales@nan-steel.com

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