Estimation of the temperature of a steel product
AssigneeArcelorMittal
InventorsNoëlle Micque, Gwenaël Le Noc, Morgan Ferte
Life of this patent
Estimating the term…
Abstract
A method for estimating the temperature of a steel product including a calibration step wherein the intensities at 5 wavelengths ranging from 0.9 to 2.1 μm are recorded for several measurement condition and spectral attenuation coefficients are computed, a measurement step wherein the intensities at said 5 wavelengths are recorded and spectral attenuation coefficients are computed for several temperatures and a comparison step wherein a probability test is performed to estimate the steel product temperature.
Claims13
A method for cooling a steel product, having a temperature from 300° C. to 1600° C., the method comprising:
- performing a cooling treatment during or following:
- a hot rolling and the steel product has a temperature from 300° C. to 1100° C. and wherein in step B, TJ ranges from 300° C. to 1100° C., or
- a continuous casting and said steel product has a temperature from 800° C. to 1600° C. and wherein in step B, TJ ranges from 800° C. to 1600° C.;
- A. a calibration step including the steps of
- i. measuring intensities (I),
- at 5 wavelengths (λ) ranging from 0.9 to 2.1 μm, wherein one is from 0.9 μm to 1.35 μm, one is from 1.35 μm to 1.55 μm, one is from 1.55 μm to 1.85 μm, one is from 1.85 μm to 2.05 μm and one is from 2.05 μm to 2.1 μm, by a hyperspectral camera,
- of the radiation emitted by the steel product having a known temperature (TREF) in measurement conditions characterized by an emissivity of the reference (εREF) and a transmittance of a medium between the steel product and the hyperspectral camera (αREF),
- ii. computing a spectral attenuation coefficient CCALIB using the measured intensities (I) at the 5 wavelengths,
- C
- CALIB
- =
- I
- P
-
- (
- λ
- ,
- T
- REF
- )
- =
- ε
- REF
- ·
- α
- REF
- where P(λ, TREF) is the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium, based on the Planck Law, at a wavelength (λ) and at a temperature (TREF),
- iii. repeating the steps i. and ii. for NCALIB different combination of reference emissivity (εREF) and transmittance of a medium between the reference and said sensor hyperspectral camera (αREF) to obtain NCALIB spectral attenuation coefficients, NCALIB being an integer greater than 2,
- B. a measurement step including the steps of
- i. measuring, by the hyperspectral camera, intensities of the radiation emitted by the steel product, I, at the 5 wavelengths (λ) ranging from 0.9 to 2.1 μm,
- ii. computing NT spectral attenuation coefficients CCOMPUTETj, for NT temperatures (Tj) ranging from 300 to 1600° C. and for the 5 wavelengths, NT being an integer from 2 to 1300,
- C
- COMPUTE
-
- T
-
- j
- =
- 1
- P
-
- (
- λ
- ,
- Tj
- )
- =
- ε
- COMPUTE
- ×
- α
- COMPUTE
- where
- P(λ, TJ) is the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium, based on the Planck Law, at a wavelength of λ and at a temperature TJ, and
- C. a comparison step including the steps of
- i. performing a probability test for finding a most likely CCOMPUTETj among the CCALIB
- ii. estimating a temperature of the steel product, TREAL as being equal to the temperature TJ of the most likely CCOMPUTETJ;
- and
- adjusting the cooling treatment as a function of the estimated the temperature of the steel product, TREAL.
Dependencies are inferred from the claim text.