To make the square tubes of the products processed now have a small degree of flexibility, we have to rely on the mechanical straightening machine to complete the straightening machine from east to west. Therefore, in order to eliminate the twists and turns of square tubes, all square tubes need to undergo cold straightening. The bending of square pipe is caused by improper adjustment of rolling mill, residual stress during rolling and unequal cooling along the section and length of pipe. Therefore, it is impossible to get very straight pipes directly from the rolling mill. Only by cold straightening the pipe's flexibility can the rules of skill conditions be satisfied.
The basic principle of straightening is to make square pipe elastic-plastic twist, from large twist to small twist, so it is necessary for steel pipe to be repeated twist in straightening machine. The degree of repeated twists and turns of steel pipe is mainly determined by the adjustment of straightening machine.
There are many factors affecting the quality of straightening, such as the bending degree of the original pipe, the size of the steel pipe and the type of straightening machine for materials, and the adjustment of parameters.