Back to results
US 2025/0019791 A1Published application
Atmosphere furnace control
OwnerAhmed KHELASSI, Walter DAL'MAZ SILVA +1inventors
InventorsAhmed KHELASSI, Walter DAL'MAZ SILVA, Morvan PLUNIAN
Life of this patent
Estimating the term…
Abstract
A method for regulating an atmosphere A inside a furnace, wherein a steel strip having a composition and an exposed surface area A1 is heat treated from a time T0 to a time TS1END and a steel strip, having a composition and an exposed surface area is heat treated from a time TS2START to a time TN, including the following steps: a data acquisition step, an optimisation step and an injection of H2O.
Claims8
1-7. (canceled)
8:
- A method for regulating an atmosphere A including H2 and N2, inside a furnace, wherein a steel strip S1 having a composition C1 and an exposed surface area ASURF1 is heat treated from a time T0 to a time TS1END and a steel strip S2, having a composition C2 and an exposed surface area ASURF2 is heat treated from a time TS2START to a time TN, the method comprising the following steps:
- A. a data acquisition step wherein:
- i. at a time T0, the dew point, DP0, of the atmosphere A is measured,
- ii. a target atmosphere ATAR1, for the steel strip S1 is retrieved, wherein the target atmosphere ATAR1 includes at least a dew point value,
- iii. a target atmosphere ATAR2, for the steel strip S2 is retrieved, wherein the target atmosphere ATAR2 includes at least a second dew point value,
- B. a tuning step including the steps of:
- i. defining N projected atmospheres, APRO-1 to APRO-N, corresponding at N times, T1 to TN, based on:
- a) the dew point, DP0, of the atmosphere measured at the time T0,
- b) the volume of the furnace,
- c) the compositions C1, C2 and the exposed surface areas ASURF1, ASURF2 of steel strips S1 and S2 inside the furnace for each of the times T1 to TN,
- ii. estimating an amount of H2O to be injected, QH2O, at TI inside the furnace using a model predictive control controller using the following data:
- a) the projected atmospheres APRO-1 to APRO-N
- b) the target atmospheres ATAR1 and ATAR2
- c) the volume and the renewal flow of N2 and H2 of the furnace, and
- d) the composition and the exposed surface area of the steel strip S1 at T1,
- C. injecting at T1 the estimated amount of H2O.
13 more elements
9:
- The method as recited in claim 8 wherein the heat treatment is an annealing.
10:
- The method as recited in claim 8 wherein the steel strip includes, in weight percent, from 0.0001% to 0.50% of C, from 0.01% to 5.0% of Mn, from 0.001% to 5.0% of Si.
11:
- The method as recited in claim 8 wherein N is a positive integer from 2 to 100.
12:
- The method as recited in claim 8 wherein each of the times T0 to TN are spaced from 5 seconds to 1 minute apart
13:
- The method as recited in claim 8 wherein in step B.i., the definition is done assuming that the temperature and the pressure of the atmosphere are constant for the times T1 to TN.
14:
- A method for regulating an atmosphere A, comprising H2 and N2, inside a furnace, wherein a steel strip S1 having a composition C1 and an exposed surface area A1 is heat treated from a time T0 to a time TN, comprising the following steps:
- A. a data acquisition step wherein:
- i. at a time T0, the dew point, DP0, of the atmosphere A is measured,
- ii. a target atmosphere, ATAR1, for the steel strip S1 is retrieved, wherein said target atmosphere ATARI includes at least a dew point value,
- B. a tuning step comprising the steps of:
- i. defining n projected atmospheres, APRO-1 to APRO-N, for n times, T1 to TN, based on:
- a) the dew point, DP0, of the atmosphere measured at the time T0,
- b) the volume of the furnace,
- c) the composition and the exposed surface area of the steel strip S1 inside the furnace for each of said times T1 to TN,
- ii. estimating an amount of H2O to be injected, QH2O, at T1 inside the furnace using a model predictive control controller using the following data:
- a) the projected atmospheres APRO-1 to APRO-N
- b) the target atmosphere ATAR1
- c) the volume and the renewal flow of H2 and N2 of the furnace,
- d) the composition and the exposed surface area of the steel strip S1 inside the furnace at T1,
- C. injecting at T1 the estimated amount of H2O.
12 more elements