Design and optimization of rolling mills pass based on parameterization and orthogonal test

Abstract

The complex design of the duo cold-mill, especially the pass. Aiming at this challenge, a parametric mathematical model of the pass is established in the present study. The cold rolling process of 50 pairs of tubes with reasonable actual rolling quality is simulated to obtain the change law of the rolling force. In the trial rolling test, it is found that there is a small part, which does not have ideal quality. In order to improve the quality of these rolling mills, tube rolling specifications for Φ43 mm × 6 mm~Φ25.4 mm × 1.2 mm are considered as an example, where the dimensional precision of the production tube is considered as the objective function and the change laws of rolling force are considered as the constraint condition. Furthermore, the orthogonal test is used to solve the constraint conditions for finding the best combination of seven design variables of the pass curve. Then the dimension of the pass curve is optimized by best combination. The optimization results show that the change laws of rolling force accord with the constraint conditions, and the average value of ΔD, γ, ΔS, and μ decreases by 63.00%, 62.89%, 58.10%, and 58.10%, respectively. It is concluded that the precision of the optimized pass is obviously better than that of the original pass. Finally, in order to verify the universality of the optimization method, the best design parameter combination for selected 20 groups of different specifications of tube rolling is investigated by the orthogonal test and the trial rolling test is carried out accordingly. The obtained results show that 90% of the rolling effect is ideal.