Wire rod mill is a kind of rolling mill specially used for rolling wire rod. Wire rod is the product with the smallest interruption surface size. The total elongation coefficient is large when the product is rolled from billet to finished product. The rolling piece is usually rolled only once on each rolling mill. Therefore, wire rod mill is the rolling mill with the largest number of stands and the finest division of labor in the hot rolled section. At present, the modern continuous wire rod mill is generally composed of 21 to 28 rolling mills, which are divided into roughing mill, intermediate mill, and finishing mill. The intermediate mill is sometimes divided into two groups, one intermediate mill, and two medium mills. The structure and layout of wire rolling mill have been developing in the direction of high speed, continuous, non-twisting, single line, combined structure, mechanization, and automation.
Wire rod mill has roughing rolling, intermediating rolling and finishing rolling. Roughing rolling mill, intermediate rolling mill, and finishing mill are arranged in horizontal, semi-continuous and continuous forms, while continuous finishing mill includes horizontal two-roll type, horizontal-vertical alternating type, 45-degree non-twist rolling mill, and Y type rolling mill. A new type of closed roughing and an intermediate rolling mill with the alternating horizontal and vertical arrangement, cantilever non-torsional pre-finishing mill, super heavy top-crossing 45-degree non-torsional finishing mill should be adopted. Non-torsional rolling, tension-free and micro-tension rolling technology should be adopted throughout the line. Start-stop flying shears should be set before rough rolling, medium rolling and finishing rolling to ensure that the rolling speed is not less than 100 m/s and the maximum coil is reached. The single weight is not less than 1.8T. Water cooling devices are installed in front of the finishing mill, between the stands of the finishing mill and behind the finishing mill. Temperature control rolling and cooling control are carried out. Precision rolling is carried out by the sizing and reducing mill, and on-line diameter gauge and flaw detector are equipped. In the production of high-speed wire rod, the key equipment of rolling wire into coils for collection is adopted. The speed of the new spinning machine is over 100 m/s.
The length of roll air-cooled transport line with large air volume delay is not less than 90 M. The direction of the blower and air volume can be adjusted automatically. There are several drops in the air-cooled line for uniform cooling. Walking beam heating furnace is used in the heating furnace of wire rolling mill. It has the functions of automatic steel burning and optimum combustion control. High-pressure water descaling device is installed in front of the rolling mill, and the pressure is not less than 18 MPa. In addition, there are perfect collection and transportation systems, such as automatic volume collection, transportation, bundling, weighing and so on. The main drive motor of wire rolling mill is fully digital AC variable frequency speed regulation.
