Research on the reduction of the hydrogen content in steels treated in vacuum

This paper discusses the results of the research on the influence of the vacuuming technological factors on the hydrogen content in the steel produced in an electric furnace type EBT, treated outside the furnice in Ladle-Furnace (LF) and Vacuum Degassing (VD) facilities, and then continuously casted as semi round products designed for pipes manufacturing. Vacumming main parameters were followed such as: the total duration of vacuuming, the duration of advanced vacuuming, the pressure in the vacuum facility, the vacumming temperature drop during the treatment (considered independent parameters) and the amount of hydrogen removed from the metal bath during the vacuuming. The obtained data was processed in the MATLAB calculation program, using three types of equations, the results obtained being presented both in analytical and graphical form. The technological analysis of the correlation equations and the graphical representations allowed to establish the variation limits of the independent parameters in order to advancely reduce the steel hydrogen content.