Good temperature control is the guarantee for the successful completion of the metallurgical process. For example, dephosphorization requires not only high oxidizing and high alkalinity slag, but also good temperature matching. This is the reason why the dephosphorization should be emphasized at an early stage. Because at that time, the lower temperature is conducive to the dish-off; in the oxidative refining period, in order to cause active carbon-oxygen boiling, a higher temperature (greater than 15503â„4) is required; metallurgical engineering is to make the post-treatment and the casting normally proceed, according to The different processes used require a certain degree of superheat in the initial steelmaking of the electric furnace to compensate for the temperature loss during the tapping process, refining outside the furnace, and the transport of molten steel.
The tapping temperature should be determined according to the steel grade and taking full account of the above factors. The tapping temperature is too low, the fluidity of the molten steel is poor, and it is easy to cause short-strip or bagged steel after casting; the metallurgical engineering tapping temperature is too high, the steel cleanliness is deteriorated, the billet (or ingot) defects are increased, and the consumption is increased. . In short, the tapping temperature should be controlled to a lower level under the premise that the casting can be successfully completed.
The eccentric bottom tapping electric furnace has a low tapping temperature (small tapping temperature drop) saves energy and reduces phosphorus return.
Modern electric furnace alloying is generally done in the ladle during the tapping process. Alloys that are difficult to vaporize and have a high melting point, such as Ni, W, Mo, etc., can be added to the furnace after melting, but when used for steel retention The influence of the composition of the forehearth steel on the molten steel of the next furnace should be fully considered. When metallurgical engineering tapping, it is necessary to adjust the tapping temperature according to the amount of alloy added. Together with the good ladle baking and heat compensation in the ladle, it can improve the alloy yield without causing low temperature.
When the steel is tapped, the alloy is pre-alloyed, and the precise alloy composition adjustment is finally completed in the refining furnace. In order to make the adjustment of the components in the refining process go smoothly, the metallurgical engineering requires that the components to be pre-alloyed do not exceed the specification limit.