There are four guide rollers in total, and the height of the guide rollers is 60mm~90mm, which are used for the entrance of the rolling mill for the pre-finishing of rods and wires, the entrance of the slitting hole and the pre-slitting hole. There are four eccentric shafts, each equipped with a guide roller. "One worm + four gears" adjusts the opening and closing of four eccentric shafts, thereby adjusting the opening of two pairs of guide rollers. During adjustment, the two pairs of guide rollers open and close in parallel, so that the openings of the front and rear pairs of guide rollers are always kept consistent, but this guide structure is relatively complicated. Guide roller bearings are lubricated with oil, gas or grease. Cooling water enters from the box body and sprays out from the water spray holes on the box body to cool the respective guide rollers. The pass type is neutral.