Influence of Hot Rolled Coil Quality on Forming and Welding of HFW Pipe

In recent years, using hot-rolled coils as raw materials, the process of HFW high-frequency welding + thermal tension reduction + full tube body heat treatment has been widely used to produce high-precision, high-grade steel casings. In production applications, it is found that the quality of hot-rolled coils directly affects the forming quality, unit operation rate and yield of HFW welded pipes.

Therefore, by analyzing the influencing factors of the quality of the hot-rolled coil, and then improving the smelting, rolling and slitting and other processes to control the quality of the hot-rolled coil, it can provide a good guarantee for the forming and welding of the welded pipe.

Four directions:

(1) Reasonable design of the chemical composition of the coil, through the improvement of the smelting and rolling process, reducing the band structure, reducing the inclusions, and improving the purity of the raw materials, can effectively improve the weldability and comprehensive performance of the HFW welded pipe.

(2) Precise control of the geometrical dimensional accuracy of the coiled plate from the process of coil rolling, slitting and edge milling can provide a guarantee for the precise forming and stable welding of the tube blank, and at the same time, it is beneficial to improve the geometrical accuracy of the final product.

(3) By optimizing the hot rolling process and equipment, controlling the appearance defects such as camber bend, tower shape, wave bend, pit, scratch, etc., can effectively improve the forming and welding quality of HFW welded pipe, and improve the yield.

(4) Through the optimization of the slitting process, the coiled plate can obtain good section quality, and at the same time, the optimal uncoiling method can be selected during feeding, which can create good conditions for HFW welded pipe forming and welding and weld bead burr removal.