DE1533931B1 - Process for the production of large blocks from pure electrical steel using the multiple furnace method - Google Patents

Description

The present invention relates to a method of making large blocks from pure Electric steel using the multiple furnace method.

Do you want z. B. Blocks of 160 or 2001 or produce more electric steel quality, the capacity of the electric steel mill is often insufficient for this. Attempts have already been made to mix batches from electric furnaces with batches from high-quality Scrap was melted in the SM furnace. This ver

Influence of the heat tint was alloyed with silicon, liquid in a hearth furnace or something else suitable unit is fed that in this unit, preferably with the entrainment of the electric furnace produced white slag brought the carbon content to the desired starting value and the character of the Eloschmelze is maintained by reducing the slag, whereby slagged Alloy elements are reduced, and

searches have failed, however, because a uniform io that then the stored batch of electrical steel

Electric steel quality of the blocks is not achieved. Also the melting or remelting of electrical steel blocks Another smelting unit does not bring the desired success because the steel is accommodated the action of the heating medium takes on a different character.

It is already known to carry out large blocks using the multiple furnace method. It also belong already transferring processes (see specialist book »The stainless steel character with another in another or the batch generated in the same electric furnace, possibly with the activation of a degassing system, is poured together.

The present invention has the advantage that when only one batch is kept warm occurring stratification processes and quality changes of the steel do not occur. The method according to the invention also has advantages

production «by Leitner and Plucking er, 1950, 20 parts in qualitative terms. It turned out-S. 324, Paragraphs 1 and 2) to the known state of the art, that in the SM furnace, if necessary, according to ausnik, where the steelmaking process in time

successive work stages are dismantled, which are carried out in different ovens. It is here on the duplex process between the blowing process in converters and the SM or Arc furnace as well as between the SM and arc furnace pointed out. Here the quality is the same the end product the quality of the product of the furnace

sufficient lime or lime fluorspar addition or, if a white slag is used, another Desulfurization takes place.

The starting point is an electric steelworks, which consists of three electric furnaces, one of which is the first 1001, second 201 and third 101 capacitance having. In all three electric ovens, accordingly the capacity of the same, scrap and

or the melting process, which charges the last phase of the 30 stroke. After 5 hours has elapsed

the batch melted in the first electric furnace is removed in liquid form and placed in a correspondingly preheated one Hearth furnace or other suitable unit fed in after a carburization to ~ 0.8 ° / oC has taken place and a silicon content of ~ 0.2% or more has been set. The liquid batches of 20 and 101 also removed and fed into the large electric furnace. It will then be scrap in sol-

Melting process forms. These methods have the disadvantage that the average quality of the in general The steel obtained by the final process does not correspond to the steel obtained exclusively by this final process will be produced.

When you have large blocks of well-defined
If you want to maintain good quality, you are therefore forced to cast heavy forging blocks
to use several ovens of the same type (see technical book "Gießgrubentechnik am Siemens-Martin-Ofen" 40 rather amount added, like the desired block by GN Oiks, 1953, pp. 87 and 88). This process variable corresponds to. In the present case it is assumed that they have the disadvantage that care must be taken that 100 t must be in the course of the second melt that the melt must be melted in the various first electric furnace. There is as little difference as possible in terms of time during the ovens. This requires the melting time of this second batch in the first electrode a careful selection of the insert and a furnace, the steel fed into the hearth furnace is well-dosed design of the heat conditions in each of the furnaces using sulfur-free or low-sulfur heating. In addition, there is the disadvantage of using a medium of about 0.8% C on the target analysis that one refreshes a considerable amount of time on the casting side, which has to operate the period of time in order to fill a single mold for the production of the second Electric steel batch in len. So you need, since to a certain extent all 50 corresponds to the first electric furnace. In the hearth furnace, the casting process is coordinated with the white slag from the electric furnace at the same time, several casting processes and pouring pan work or the fresh slag is reduced by reducing it. This process requires considerable operational resources to bring back the character of the electrical engineering difficulties in the precise coordination of the nungsschlacke. The way the ovens work in the hearth oven. The 55th electrical charge is then carried out with the

The present invention has the task of pouring together a second batch produced,

posed, using large blocks of electrical steel, resulting in a material that is of quality

at least one electric furnace and one non-elec- tric steel is at least equivalent, but

Irish heated hearth furnace without often having an even lower sulfur content,

as a result, the steel quality is impaired or a higher level than is generally achievable with electrical steel

Considerable operational expenditure under compli- is.

Adorned coordination of simultaneous cooperation of the furnace units take place during the casting process got to.

The invention solves this problem in that after completion of a batch in an electric furnace the same is carburized and that the carburized batch, after this possibly still for loading

Claims (2)

Patent claims: 1. A method of making large blocks of pure electrical steel using the multiple furnace method, characterized in that after completion of a batch in an electric furnace the- the same carburized and then, preferably with the entrainment of the white ones produced in the electric furnace Slag is fed into a hearth furnace or some other suitable unit that is in the SM furnace the carbon content is reduced to the desired initial value while in the a second batch of the aforementioned or one or more other electric furnaces is completed, and that the batch stored in the hearth furnace and the batch generated in the electric furnace, possibly after prior degassing, be cast together in a mold. 2. The method according to claim 1, characterized in that the in the hearth furnace or something else suitable aggregate to be fed in by adding silicon is alloyed in order to achieve an increased heat tint when freshening.