VDEh-Betriebsforschungsinstitut (Institute of Industrial Researches, Union of German Metallurgists) (Düsseldorf, Germany):

Kordel T., Dr. Nat., Mag. Phys., Project Leader, Technological Measuring Devices for Metallurgy, tobias.kordel@bfi.de
Lamp T., Dr. Nat., Mag. Eng., Project Group Leader, Technological Measuring Devices for Metallurgy
Köchner H., Dr. Eng., Mag. Phys., Dept. Leader, Technological Measuring Devices for Metallurgy

Minkon Sampler-Technik GmbH (Erkrath, Germany):

Fischer H., Mag. Eng., Technical Director

Peiner Träger GmbH (Peine, Germany):

Zagrebin V., Mag. Eng., Head of Secondary Metallurgy

In electric steel making process, steel melt temperature in electric arc furnaces and ladle furnaces is regulated to reach the required value for pouring. Spotted heating of bath surface via electric arc leads to local thermal deviations and oscillations in time. In order to provide continuous temperature melt measurement, fiber optic DynTemp method is used; it allows to determine temperature in the ladle with accuracy ± 2K, including measurements at electric arcs switched-on, during one minute. It is shown that the values of measured bath surface temperature after electric arc switching-off are located much higher that average calculated value. Afterwards diffe rence in melt temperature is equalized and temperature fluctuations after electric arc switchingoff and bottom blowing reduced from ±30K to ±5K in 30 seconds. Measurements using thermal elements doesn't allow to reveal existing temperature fluctuations that increase mistake in determination of the melt average temperature in the ladle. It should be taken into account as temperature reserve for consequent production stages. Continuous measuring method allows for the first time to account fluctuations and bath surface temperature decrease, while continuous fiber optic temperature measuring makes it possible to decrease assurance temperature reserve for overheating and. as a result, to save electric power.

1. Köchner, H.; Lamp, T.; Fischer, H.: Continuous optical temperature measurement for liquid steel temperature control, Proc. 1. Intern. Conf. on Energy Efficiency and CO₂ Reduction in the Steel Industry (EECR 2011), Düsseldorf, 29. Juni 2011.
2. Köchner, H.; Lamp, T.: stahl u. eisen 129 (2009) Nr. 3, S. 39/45.