La presente invenzione riguarda un apparato per la lavorazione dell'acciaio ad alto risparmio energetico ed un metodo relativo, in particolare per la laminazione di profilati o barre.

Piu precisamente, I'invenzione si riferisce a un apparato che preveda la laminazione per la produzione di laminati, come ad esempio profilati o barre, che permetta di ridurre il dispendio di energia termica, necessaria al raggiungimento di diverse temperature, nonche di abbattere le emissioni di alcune sostanze inquinanti.

Attualmente sono noti impianti di laminazione come quello mostrato in figura 1 B ed indicato con il riferimento generico B.

La laminazione nella produzione dell'acciaio e il processo attraverso il quale si ottengono le caratteristiche meccaniche ed una forma desiderate, facendo passare il materiale da laminare, indicato con 10, in una forma di sezione maggiore rispetto a quella del prodotto finito, tra una coppia di rulli 4, lisci o scanalati.

La distanza fra i due rulli 4 e minore dello spessore del materiale entrante 10.

II materiale di partenza generalmente e una cosiddetta "billetta", ottenuta dalla solidificazione deH'acciaio in appositi impianti di colata continua, mostrati in figura 1A ed indicati con il generico riferimento A. L'acciaio, dopo essere stato colato in un'area di colata continua 5 negli stampi, passa in una zona di raffreddamento 6 in cui si solidifica sotto forma di billetta 10.

Prima di sottoporre la billetta 10 al processo di laminazione, e necessario riscaldarla in un treno preparatorio 2, portandola ad una temperatura di massima plasticita, ovvero, per l'acciaio, fra i 1000°C e i 1150°C.

II riscaldamento viene effettuato con un forno a fiamma 2A, che sono di solito e alimentato con olio pesante o gas.

L'intero processo di produzione dell'acciaio, quindi, richiede due fasi di riscaldamento del materiale: la prima, in cui si deve raggiungere una fase liquida, e la seconda, successiva ad un raffreddamento, in cui si raggiunge una fase plastica .

Tale processo comporta, di conseguenza, un notevole dispendio di energia.

Gran parte di questa energia viene dispersa - sotto forma di calore - nel process of the semi-finished products or billets or of the finished product of the rolling process.

Therefore, there is still the need to have an apparatus for processing steel capable of ensuring high energy savings during the steel processing, with respect to the apparatus that are currently used.

In particular, it is clear that there is a need to provide a method for processing steel which allows to optimize the amount of heat used to bring the steel at values of temperature necessary to the subsequent processing steps.

In addition, a second drawback of a known rolling plant is constituted by the fact that said rolling plant is not very efficient in production and space management.

In fact, in order to heat and then cool the wires of steel to be rolled, it is necessary to have space for the cooling and then for the subsequent heating.

It is clear from the foregoing that it is necessary to have an apparatus for rolling steel that involves a high production efficiency.

Again, the use of flame furnaces results in the emission of harmful substances, such as C02, S02 and NOx.

Therefore, an object of the present invention is to overcome the drawbacks of the prior art by providing an apparatus for processing steel which involves higher production efficiency with respect to the known rolling plants.

In particular, object of the present invention is to provide an apparatus for processing steel with high energy savings.

Within this object, an aim of the present invention is to provide an apparatus for processing steel which allows to reduce the overall dimensions of the plant.

Another aim of the present invention is to provide an apparatus for processing steel that avoids consumption of electrical energy and therefore reduces production costs.

A further object of the invention is to provide a method for processing steel which provides a production rate greater than the rate obtained with the known methods.

These and other objects are achieved by an apparatus for processing steel as claimed in the alleged claim 1 and by means of a method thereof according to the alleged claim 3. Further detailed technical characteristics of the apparatus and method according to the invention are indicated in the dependent claims.

Advantageously, the integration between steel mill and rolling mill through a direct hot charge leads to considerable energy savings by also reducing the production costs to more than 300 kWh/t.

Another advantage provided by the present invention is to make the steel production more sustainable from the point of view of environmental pollution.

In particular and advantageously, the heating flame furnace is not used and therefore, in addition to fuel savings, it is possible to reduce pollutants emissions, such as C02, S02 or NOx.

For example, if we consider a plant of 800,000 t/y EES, there is a reduction of 72,000 t/y in C02 emissions, a reduction of 410 t/y in S02 emissions and a reduction of 225 t/y in Nox emissions.

The present invention thus allows to make the steel production ever more environmentally friendly.

The above mentioned objects and advantages of the invention will appear to a greater extent from the following description, relating to a preferred embodiment of the apparatus for steel rolling, according to the invention, and from the enclosed drawings, in which:

- figure 1A is a diagram of a first part of an apparatus for rolling steel bars according to the prior art;

- figure 1 B is a diagram of a second part of the apparatus for rolling steel bars according to the prior art;

- figure 2 is a diagram of the apparatus for rolling steel bars according to the present invention.

Referring particularly to figure 2, the rolling apparatus according to the invention, indicated with 1 , includes a setting train 2 facing a finishing train 3, which comprises a plurality of cages 4.

The layout of the apparatus provides a direct connection from the continuous casting plant 5 to the setting train 2 of the rolling mill, by means of fast transport means 7 of the billets 10, which are totally solidified and which have an average temperature ranging from 850°C to 900°C.

Since the rolling temperature suitable for a proper plasticity of the material must be greater than 1000°C, it is necessary to bring the billets 10 to said rolling temperature.

Therefore, the setting train 2 provides an induction-type tunnel furnace 2B. Thus, the temperature needed for rolling is quickly reached and it is possible to proceed with the processing of the billets by means of the pairs of rolls 4 of the finishing train 3, with an energy consumption which is greatly reduced with respect to the prior art.

Advantageously, the apparatus for processing steel according to the present invention allows to reduce the overall dimensions with respect to the known plants, thus avoiding the space needed for cooling the billets and for their storage.

The method for processing steel according to the present invention provides the following steps:

a. taking the steel to a melting temperature greater than 1500°C;

b. casting the steel into moulds, thus obtaining a semi-finished product; c. transferring the semi-finished casted product to a rolling mill by means of fast transport means;

d. taking the semi-finished product to a temperature of maximum plasticity (greater than 1000°C);

e. subjecting the semi-finished product to a rolling process.

In particular, step c. allows a reduction of the steel temperature to around 800-900°C, thus also allowing a complete solidification of the material, that acquires the mechanical properties required for the finished products to be placed on the market.

More in detail, step d. takes place preferably using induction-type furnaces, which limit the emissions of the above mentioned pollutants. Even more in detail, the rolling process mentioned in step e. can take place by using preferably a known rolling mill plant.

The features, as well as the advantages, of the high production rolling apparatus, in particular for rolling steel bars and sections, which is the object of the present invention, are clear from the above description.

Finally, although the invention has been described for illustrative but not limitative purposes, according to a preferred embodiment, it is to be understood that variations and/or modifications can be made by those skilled in the art, without departing from the scope of protection as set forth in the appended claims.