The cold rolling mill is a new type of cold-rolled steel processing equipment. The machine can process hot-rolled wire rods and hot-rolled coils with a diameter between 6.5 mm and 12 mm into cold-rolled ribbed steel bars with a diameter of 5 mm to 12 mm. It has types including 4hi cold rolling mill, 2 hi cold rolling mill, two-ribbed cold rolling mill, spiral blade cold rolling machine, flat steel cold rolling mill. It adopts an electric motor to drag the reinforcing bars and uses the load-bearing rolls, mill rolls to apply force on both sides of the reinforcing bars. The purpose of rolling cold-rolled ribbed bars with different diameters is achieved by changing the size of the gap between the two rolls. The equipment can simultaneously process the warp and weft directions of the base material during the cold rolling process. Under the premise of maintaining the relative balance and stability of the product in the center area of the original cross-section, improve the resistance and compression, still retaining sufficient elongation performance.