Heating method of a metallic product

Abstract

A method for heating a semi-finished steel product, including a pre-heating step, performed in a pre-heating device including a chamber containing solid particles, a heat exchanger, a support able to support the semi-finished steel product, a gas injector, and a heating step, performed in a furnace, wherein, the pre-heating step includes the steps of i. injecting a gas into the first chamber so as to form a first fluidized bed, ii. heating the fluidized bed by the heat exchanger, iii. putting the semi-finished steel product, into the fluidized bed and onto the support such the fluidized bed is able to transfer heat to the semi-finished steel product, iv. taking out the semi-finished steel product when its temperature is from 200° C. to 1000° C., and the heating step includes the step heating the semi-finished product to a temperature from 1100 to 1400° C.

What is claimed is: 
     
         1 - 9 . (canceled) 
     
     
         10 . A method for heating a semi-finished steel product, the semi-finished steel product being a slab, a billet or a bloom, the method comprising:
 a pre-heating step performed in a pre-heating device having a chamber containing solid particles, a heat exchanger, a support able to support the semi-finished steel product, and a gas injector; and   a heating step performed in a furnace, wherein the semi-finished steel product is heated to a temperature from 1000 to 1400° C.;   a hot rolling step, after the heating step, wherein the semi-finished steel product is hot rolled;   the pre-heating step including the steps of:
 i. injecting a gas into the first chamber so as to form a first fluidized bed; 
 ii. heating the fluidized bed via said heat exchanger; 
 iii. putting the semi-finished steel product into the fluidized bed such that the semi-finish steel product is supported by said support  6  and such that the fluidized bed is able to transfer heat to said semi-finished steel product; and 
 iv. taking out the semi-finished steel product when a temperature of the semi-finished steel product is from 200° C. to 1000° C. 
   
     
     
         11 . The method as recited in  claim 10  wherein the gas injected in the chamber is air. 
     
     
         12 . The method as recited in  claim 10  wherein solid particles of the fluidized bed are in a bubbling regime. 
     
     
         13 . The method as recited in  claim 10  wherein in step ii., the fluidized bed is heated at a temperature from 400 to 700° C. 
     
     
         14 . The method as recited in  claim 10  wherein in step ii., the fluidized bed is heated at a temperature from 500 to 700° C. 
     
     
         15 . The method as recited in  claim 10  wherein in step ii., the fluidized bed is heated at a temperature from 600 to 700° C. 
     
     
         16 . The method as recited in  claim 10  wherein the semi-finished steel product is taken out when of the fluidized bed at a temperature from 500° C. to 700° C. 
     
     
         17 . The method as recited in  claim 10  wherein the semi-finished steel product is taken out when of the fluidized bed at a temperature from 600° C. to 700° C. 
     
     
         18 . The method as recited in  claim 10  wherein a transfer medium circulates in the heat exchanger and is introduced into the heat exchanger at a temperature from 250° C. to 1500° C. 
     
     
         19 . The method as recited in  claim 10  wherein a transfer medium circulates in the heat exchanger and exits the heat exchanger at a temperature from 150° C. to 1000° C. 
     
     
         20 . A method for heating a semi-finished steel product, the semi-finished steel product being a slab, a billet or a bloom, the method comprising:
 a heating step performed in a heating device having a chamber containing solid particles, a heat exchanger, a support able to support the semi-finished steel product, and a gas injector; and   a rolling step performed in a rolling mill,   the heating step including the steps of:
 i. injecting a gas into the first chamber so as to form a first fluidized bed; 
 ii. heating the fluidized bed via said heat exchanger; 
 iii. putting the semi-finished steel product into the fluidized bed such that the semi-finish steel product is supported by said support  6  and such that the fluidized bed is able to transfer heat to said semi-finished steel product; and 
 iv. taking out the semi-finished steel product when a temperature of the semi-finished steel product is from 150° C. to 350° C., and 
   the rolling step including the step of rolling the semi-finished steel product at a temperature from 150 to 300° C.