Novel online temperature control system with closed feedback loop for steel continuous casting

Abstract

Based on a basic water cooling model, a novel model with closed feedback loop was developed for online temperature control system (OTCS) to control the strand surface temperature online during steel continuous casting process. The OTCS considered the temperature delay to the casting speed and water flowrate and combined the feedback control model with feed forward control model for the control of secondary cooling water. The online feed forward control with the temperature of molten steel in the tundish and the temperature of cooling water was also considered. A fine adjusting temperature region and an optimal temperature region were applied to the OTCS to avoid big temperature fluctuation during control process and to shorten the adjusting time. A single point OTCS was applied to a slab continuous caster, showing that the slab surface temperature was well stabilised at the target temperature under the control of the OTCS in continuous casting process. During tundish change or big variation of casting speed, the low slab surface temperature could be quickly controlled to the target temperature again by the OTCS within 7 min. The industrial application indicated that the OTCS could reduce the slab surface cracks and aid in increasing productive efficiency in continuous casting.

Research on the On‐Line Simulation of a Three‐Dimensional Temperature Field Model of Slab Continuous Casting

“…To further verify the accuracy of the model boundary conditions, three continuous temperature measuring devices were installed on the continuous caster . In order to remove the effect of the oxide scale on the slab surface, take the maximum value within 5 s as the surface temperature.…”

“…It can be seen that basing on the simulation of the three‐dimensional temperature field the temperature in the width direction of the slab may be uniformed by the dynamic secondary cooling water model and a regular shape of the solidification end may be obtained which is the key factor for achieving good results of soft‐reduction technology . So, the dynamic secondary cooling water model and dynamic soft‐reduction model are successfully used to modify the original model in a domestic steel mill, which is the two‐dimensional temperature field version.…”

Definition of range of open applications for massive nodes in the stainless steel castings

“…Обсяг усадочних раковин і пор, навіть для сталі 110М13Л, не перевищує 7,0%, але для того, щоб заповнити цей обсяг рідким металом з додатка, обсяг Для виявлення зони поширення пористості у вузлах виливка з нержавіючої сталі, було спроектовано два найпоширеніші варіанти розміщення масивних вузлів на стінці виливки, перший -коли вузол знаходиться на краю виливка, другий -коли в середині стінки. Аналіз теплових полів, отриманих при моделюванні кристалізації наших зразків, показує місця сильного перегріву, відповідно ці теплові вузли будуть тверднути останніми [11][12][13]. Встановлені прибутки дозволили вирівняти температурні поля більшої частини поверхні виливка, таким чином усереднити час і момент кристалізації всього вузла.…”

Improvement of the secondary cooling mode for continuous casting of round billets at Ural Steel JSC

“…At the same time, despite the large amount of publications devoted to this theme, the problems of quality improvement of continuously cast billet and optimization of technical and economical casting parameters can be solved in general individually in each single case. Thereby scientific and technical literature includes a lot of publications describing simulation of the heat state of a continuously cast billet [8,9,[12][13][14][15][16], as well as the results of investigations aimed on modernization of equipment and improvement of technologies for continuous casting in different production conditions: Pangang Group Chengdu Steel (China) [9], Hebei Iron & Steel Group (China) [10,17], Xingtai Steel (China) [18], Panzhihua Steel (China) [19], Zhongyuan Special Steel (China) [20], Voestalpine Stahl (Austria) [21,22], "Ural Steel" (Russia) [23][24][25], "UMMC-Steel" (Russia) [26], Mini-metallurgical plant "ISTIL" (Ukraine) [27].…”