http://arthra.ugal.ro/handle/20.500.14043/25936 2026-04-10T04:24:17Z http://arthra.ugal.ro/handle/20.500.14043/25945 The Dynamic Simulation for a Cold Rolling Mill Machine Dragomir, Ștefan For a cold rolling mill machine that represents a mechanical system, the dynamics problems may be solved by using the differential equations of their movement. We must consider all the connections and couplings for the mill machine that have too elastic elements like: springs, shafts and axes deformed through torsion, spring bars, work rolls and back-up rolls. The vibrations of the mechanical system must be monitored in order to identify those components which cause problems when the damage of the mill occurs during the operation. In these mechanical systems, mobile rigid permanent couplings are used - which transmit shocks and vibrations - or stretch couplings - which, due to the elastic element, dampen shock and vibration. Vibrations can appear, too, because of rolling strip that can have undulations. The Annals of "Dunarea de Jos" University of Galati : Fascicle IX Metallurgy and Materials Science No. 2 - 2016, ISSN 1453 – 083X 2016-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25946 Statistical Correlations Between Chemical Composition and Mechanical Properties of A516 Grade 65 Steel Ciocan, Anișoara; Tudor, Beatrice In order to respond to required demands associated to certain operation conditions, the steels used in petroleum, petrochemical and chemical processing industries must have significant improved mechanical properties. These can be obtained by constant monitoring and controlling of parameters of steelmaking process. The determining factors responsible for improving the mechanical properties of steel are chemical composition, purity and the technological parameters. The injection of an inert gas or by vacuum exposure is effective in reducing non-metallic inclusions and for chemical composition control. These treatments are comprised in the secondary metallurgy and require special installations. It is cheaper to create a modeling tool that can be used for the prediction of mechanical properties, directly in the steel production process by variating its chemical composition. In this paper, by using the linear regression technique, the relationships between certain mechanical properties and the chemical composition of steel A516 Grade 65 have been determined. The Annals of "Dunarea de Jos" University of Galati : Fascicle IX Metallurgy and Materials Science No. 2 - 2016, ISSN 1453 – 083X 2016-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25944 Research in industrial trials to Improve Through-Thickness Z35 Properties of Hot Rolled Heavy plates up to 60 MM Thickness for Structural Steels Durduc, Costel; Gurău, Liviu; Drugescu, Elena; Mușat, Viorica The main purpose of this industrial experimental rolling, done in ArcelorMittal Galati in the Heavy Plate Mill is to check the correlation between mechanical properties and the microstructure of chemical compositions used in trial in order to reach through-thickness Z properties. First chemical composition is C_Mn steel with mechanical properties designed to reach at least 275 MPa on yield strength. The other chemical composition is based on Nb and Ti alloying elements with mechanical properties designed to be equal or higher than 360 MPa. In total, four slabs with 250 mm thickness were rolled. Two slabs with targeted plates thickness of 22.5 mm and 60 mm were used in trial per each chemical composition in order to check the thickness feasibility of targeted through-thickness Z properties. The Annals of "Dunarea de Jos" University of Galati Fascicle IX Metallurgy and Materials Science 2016-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25943 Industrial Research in Thicker Heavy Plates (70-80 MM) HSLA Steel Micro-Alloyed with Mo-NB-Ti Thermo-Mechanical Control Process in ArcelorMittal Galati Durduc, Costel; Gurău, Liviu; Drugescu, Elena; Mușat, Viorica Thermomechanical rolling (TMR or TMCP) is a special rolling process resulting in an extremely high-strength, fine-grained substructure which simultaneously offers very good toughness and cold formability. TM products have much lower carbon content and consequently are much less susceptible to cold cracks during welding. In ArcelorMittal Galati the challenge was to increase for structural steel the feasibility from 50 up to 80 mm and targeted plate thickness without ACC mode. Slabs thickness produced in AMG with maximum 250 mm thickness corresponding to almost the maximum ratio of 3:1 between slabs and targeted plate thickness according to the EN 10025/4/2004. TM rolled steels performed in industrial trial presented in this paper were performed in Heavy Plate Mill no 2 in ArcelorMittal Galați using computer process SIROLL assisted by AGC system. The main goal of this experimental rolling is to provide a concise and complete overview of the rolling process with higher amount of deformation below Tnr (non-recrystallisation temperature) and close to Ar3 in austenite region, and to address the potential to optimize it. The Annals of "Dunarea de Jos" University of Galati Fascicle IX Metallurgy and Materials Science No. 2 - 2016, ISSN 1453 – 083X 2016-01-01T00:00:00Z