Plant to produce steel, and corresponding method

Abstract

Steel production plant to obtain long products such as rods, bars or sections, with overall productivity comprised between 0.7-3.0 Mton/year, preferably between 1.0 and 3.0 Mton/year, comprising at least two co-rolling lines (11a, 11b).

1 . A steel, Steel production plant to obtain long products such as rods, bars or sections, with overall productivity comprised between 0.7-3.0 Mton/year, preferably between 1.0 and 3.0 Mton/year, comprising at least two co-rolling lines, wherein it provides a single high-capacity melting furnace and at least two ladles to receive the liquid steel from said melting furnace and feed said co-rolling lines, wherein the total useful capacity of the at least two ladles expressed in tons does not exceed the capacity in tons of the liquid steel tapped from said melting furnace. 
     
     
         2 . The steel production plant as in  claim 1 , wherein the at least two ladles have the same useful capacity and substantially equal, together, to the capacity in tons of tapped steel of the single melting furnace. 
     
     
         3 . The steel production plant as in  claim 1 , wherein the at least two ladles have different useful capacities and substantially equal, together, to the capacity in tons of tapped steel of the single melting furnace. 
     
     
         4 . The steel production plant as in  claim 1 , comprising at least two secondary metallurgy stations for executing refining and/or thermal or other treatments. 
     
     
         5 . The steel production plant as in  claim 1 , comprising hoppers to add alloy elements directly to the ladle during the step of tapping from the melting furnace. 
     
     
         6 . The steel production plant as in  claim 1 , wherein the furnace is of the tiltable type. 
     
     
         7 . The steel production plant as in  claim 6 , wherein the furnace is of the type with pouring spout. 
     
     
         8 . The steel production plant as in  claim 6 , wherein the furnace is of the type with a tapping hole which can be selectively closed by means of closing means. 
     
     
         9 . The steel production plant as in  claim 1 , wherein the furnace is of the type with siphon tapping with tapping chamber. 
     
     
         10 . The steel production plant as in  claim 1 , wherein the furnace is of the non-tiltable type and with double lateral tapping duct. 
     
     
         11 . The steel production plant as in  claim 1 , wherein the furnace is of the tiltable type with double tapping hole. 
     
     
         12 . A method to produce steel to obtain long products such as rods, bars or sections, with productivity comprised between 0.7-3.0 Mton/year, preferably between 1.0 and 3.0 Mton/year, comprising the following steps:
 melting the steel in a single high-capacity melting furnace;   pouring the molten steel from the single melting furnace into at least two ladles whose total useful capacity expressed in tons does not exceed the capacity in tons of liquid steel tapped from said single melting furnace;   feeding with each of said at least two ladles a respective co-rolling line of a multiple co-rolling apparatus.   
     
     
         13 . The method as in  claim 12 , wherein the liquid steel contained in said two ladles is diversified by type. 
     
     
         14 . The method as in  claim 13 , wherein the diversification of the type of liquid steel occurs in the tapping step. 
     
     
         15 . The method as in  claim 13 , wherein the diversification of the type of liquid steel occurs inside the ladles in at least two secondary metallurgy stations. 
     
     
         16 . The method as in  claim 12 , wherein the co-rolling lines are equal to two, and one or both co-rolling lines work in endless mode. 
     
     
         17 . The method as in  claim 12 , wherein the co-rolling lines are equal to two, and one or both co-rolling lines work in billet-to-billet or semi-endless mode.