Jiang Z.Y.,University of Wollongong |
Tang J.,University of Wollongong |
Sun W.,Jinan Iron and Steel Company Ltd |
Tieu A.K.,University of Wollongong |
Wei D.,University of Wollongong
Tribology International | Year: 2010
In this paper, the effects of the flow stress of the scale and steel, and the friction coefficients at the scale-steel and the roll-scale interfaces on the final surface roughness have been studied. The surface roughness increases for both oxide scale and steel with an increasing friction coefficient at the roll-scale interface. However, the roughness increment is limited. The calculated roughness is close to the measured value. The temperature affects the scale roughness transfer, and the maximum difference is about 25% when the temperature is 850-1025 °C for rolling speeds 0.12-0.72 m/s. The developed model is applicable in hot strip mills. © 2010 Elsevier Ltd. All rights reserved.
Shi J.,Shandong Jianzhu University |
Yin D.,State Grid Corporation of China |
Yang G.,Jinan Iron and Steel Company Ltd
2014 10th International Conference on Natural Computation, ICNC 2014 | Year: 2014
Based on the mathematical analysis of the rolling process, an optimal load distribution model is established. The total energy consumption is to be minimized by adjusting rolling parameters. The equipment and rolling process constraints are taken into consideration. An improved particle swarm optimization algorithm is employed to get the optimal rolling parameters. The simulation results on a six-frame strip demonstrate that the proposed method is efficient. The experiment in Jinan Iron & Steel Group shows the feasibility of the rolling parameter optimization model and solving method. © 2014 IEEE.
Cao L.,Jinan Iron and Steel Company Ltd
Kang T'ieh/Iron and Steel | Year: 2015
A lot of longitudinal cracks were observed on the surface of 250 mm×1820 mm wide heavy slab containing 0.120%-0.150% carbon, produced using the protecting slag for peritectic steel in one Wide Heavy Plate Plant. These surface longitudinal and subsurface cracks have been effectively controlled by improving the basicity of mold powder, decreasing mold powder viscosity and improving the heat transfer between the mold wall and the slab shell. The reason for the slab with 0.090%-0.120% carbon be free of surface cracks is the segregation crystallization, which causes the carbon content in the initial solidified shell is lower than 0.090%. ©, 2015, Chinese Society for Metals. All right reserved.
Jiang Q.-M.,China Petroleum Pipeline Engineering Corporation |
Zhang X.-Q.,China Petroleum Pipeline Engineering Corporation |
Chen L.-Q.,Northeastern University China |
Sun W.-H.,Jinan Iron and Steel Company Ltd
Journal of Iron and Steel Research | Year: 2014
By using thermal expansion measurement combined with microscopic analysis and hardness test, the critical points Acl and Ac3 of 1000MPa grade low carbon micro-alloyed extra high-strength steel in the welding process were determined and SH-CCT diagram at different cooling rates was obtained. The influence of cooling rate on microstructure and hardness of CGHAZ was investigated to reveal the phase transition of HAZ at different cooling rates and the relationship between average austenite grain size and t 8/5 during simulated thermal circle. The results indicate that the austenitizing temperature of this steel in the welded condition is significantly higher than that in the equilibrium state. Intermediate temperature phase transformation to bainite can occur in a wide range of cooling rates. The microstructure of HAZ is mainly consisted of martensite at rapid cooling rate (≥40°C/s). The hardness decreases gradually with the increase of t 8/5 and the maximum hardness is 425(HV10). The coarsening degree of austenite grain size is insignificant on the testing condition.
Shan X.-Y.,Yanshan University |
Shan X.-Y.,Jinan Iron and Steel Company Ltd |
Liu H.-M.,Yanshan University |
Jia C.-Y.,Yanshan University |
Sun J.-L.,Yanshan University
Journal of Iron and Steel Research International | Year: 2012
Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile integration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tandem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shape control of tandem cold mills. © 2012 Central Iron and Steel Research Institute.