Improved control of mechanical and geometrical properties of steel strips by thermal profile determination all along the annealing line
The objective of this project is the application of numerical and experimental tools to better control thermal cycles of steel strips in continuous annealing lines. The innovative aspect is to give the real and complete thermal history of steel strips all along an industrial annealing line. The main task was to connect different models (heating by flames, heating by radiative tubes, soaking, cooling by cylindrical gas-jets or plane gasjets) to simulate a complete annealing line. The models of radiative heating zones use different elementary three-dimensional cells to compute radiative transfer between tubes, strips, rolls and walls of the furnace, to simulate all kinds of continuous annealing furnaces by joining different cells together. Two- and three-dimensional numerical simulations of cooling systems were performed. From the local values of the convective exchange coefficients, an average value is determined for the entire cooling box. Thus, the total thermal evolution of the strip can be calculated for an industrial configuration of cooling. Industrial measurements were made and compared with two- and threedimensional mathematical models. The good results showed the means to perform accurate simulations of temperature evolution of products in industrial annealing lines. We also investigated how the distribution of fast cooling on a continuous annealing line may affect the strip geometrical characteristic by installing a strip profile temperature measuring system at the entrance of the strip cooling section, and measuring thermal profile and flatness at the exit. It was observed that the main parameters are strip speed followed by temperature difference on the edge of the furnace exit.
Bibliographic Reference: EUR 22034 EN (2006), 110 pp. Euro: 25
Availability: Katalogue Number: KI-NA-22034-EN-S The paper version can be ordered online and the PDF version downloaded at: http://bookshop.europa.eu
ISBN: ISBN: 92-79-01379-3
Record Number: 200719295 / Last updated on: 2007-07-10
Original language: en
Available languages: en