Explanation

The equipment for continuous rolling of hollow pipes without mandrel to reduce the diameter of crude pipes is usually called reducing mill. When the reducing ratio is less than 10%, this equipment is also called sizing mill. A typical reducing mill usually consists of 9 to 24 frames. According to the number of roll on the stand, reducing mill can be divided into two roll, three roll and four roll reducing mill. According to the transmission mode, the reducing mill can be divided into joint transmission, separate transmission, differential transmission and hydraulic differential transmission. By adjusting the rotational speed of the roll, tension can be generated between the stands. If the average tension coefficient is less than 0.5, it is usually called the micro tension reducing mill; If it is greater than 0.5, it is called tension reducing mill. The tension reducing mill can not only reduce the outer diameter of the steel pipe, but also reduce the wall thickness of the steel pipe. The maximum reduction rate can usually reach 80%, while the maximum wall reduction rate can reach 40%. These machines play an important role in tube production and can be used to produce steel pipes of different specifications.

Classification