Community Research and Development Information Service - CORDIS


The main objective of this cooperative study is to obtain a better understanding of the mechanisms governing the efficiency of primary and secondary descaling, in order to give practical recommendations for the processing of different steel grades. The study was performed on descaling and hot-rolling pilot units completed with in-depth characterization of the scale-metal interface and FEM thermomechanical simulations. Industrial steel grades were used and particular focus was given to the effect of elements known for their detrimental effect on scale adhesion and descaling efficiency.

The influence of descaling parameters, such as descaling temperature, water flow rate, impact pressure and oxygen partial pressure, has been quantified in conditions close to industrial practice. As expected, the results showed that steels containing Si, Ni and Cu were most difficult for primary descaling. For each steel grade, recommendations are given in order to improve the descaling efficiency.

Furthermore, rolling experiments showed that the secondary descaling efficiency could be optimised in terms of descaling frequency. at high-impact pressures, descaling every other pass seems to give better results than descaling every pass. However, further reduction of the descaling frequency may be detrimental.

FEM simulations showed that the thermal stresses are much greater than the mechanical stresses during hydraulic descaling. For primary descaling, however, the mere cooling from the top surface of the scale cannot explain the break-up and removal of the scale. A new approach taking into account the influence of water on the lateral surfaces of the broken scale is proposed.

Finally, a new system was developed in order to quantify heat losses during secondary descaling.caling.

Additional information

Authors: NISKA J, MEFOS, Lulea (SE);JARL M, MEFOS, Lulea (SE);MIKLER M (ET AL), Institute de Recherches de la Siderurgie Francaise, Maizieres-les-Metz (FR)
Bibliographic Reference: EUR 19856 EN (2001), pp. 132. Euro: 20.50
Availability: Available from EUR-OP sales agent
ISBN: ISBN 92-894-1268-2
Record Number: 200113795 / Last updated on: 2001-09-27
Original language: en
Available languages: en