Beautiful technology of welding square pipe and rectangular pipe will develop continuously with the development of science and technology, making the welding square pipe technology more perfect and producing better and more beautiful square pipe products.

　　The following is the method of square tube aesthetics.

　　One end of the square pipe is stuffed with wooden wedges, and stands up downward (note: keep the outside for easy removal). Fill the sifted sand with a funnel while it is hot. While hammering the wall of the pipe with a hand, fill it until the dry sand is not loosened in the pipe. After filling, close into another wooden wedge.

　　2. Draw a large sample of the welded square pipe on the working platform: the outer circle radius is 50+outer diameter/2, the inner diameter is 50-outer diameter/2, and spot weld the pawl at the beginning of bending and stop to prevent overheating or underheating.

　　Three, lower fire simmer, also can use steam gun to roast to simmer. It's easy to simmer down. It's OK to simmer slowly. But if you simmer with an auto-welding gun, be careful to simmer the welded square pipe section by section. Be careful that the bottom part of the platform must be simmered to the same temperature, otherwise it will be flat!

　　4. In case of under-simmering (inadequate angle) or over-simmering (large angle), it can be corrected by pouring cold water on the inside of the fillet or heating the outside of the fillet and the reverse method.

　　Note: The sand must be stir-fried on high heat because the water in the sand is removed to prevent explosion when the square tube is fired!