US3329495A - Process for measuring the value of carbon content of a steel bath in an oxygen top-blowing converter - Google Patents

Process for measuring the value of carbon content of a steel bath in an oxygen top-blowing converter Download PDF

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US3329495A
US3329495A US398337A US39833764A US3329495A US 3329495 A US3329495 A US 3329495A US 398337 A US398337 A US 398337A US 39833764 A US39833764 A US 39833764A US 3329495 A US3329495 A US 3329495A
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value
carbon content
steel
amount
waste gas
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Ohta Takayoshi
Akuta Tomohiko
Yoshizumi Hideo
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Yawata Iron and Steel Co Ltd
Yokoyama Engineering Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/20—Metals
    • G01N33/202—Constituents thereof
    • G01N33/2022—Non-metallic constituents
    • G01N33/2025—Gaseous constituents
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/20—Metals
    • G01N33/205—Metals in liquid state, e.g. molten metals

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  • FIG. I a E 1A: in 1 n 1 "flIr- Time (in minufes) lNVENTORS Tokcyoshi Ohio Tomohiko Aku'ku Minoru Nishiwoki Hideo Yoshizumi dad/W July 4, 1967 TAKAYOSHI OHTA ETAL PROCESS FOR MEASURING THE VALUE OF CARBON CONTENT OF A STEEL BATH IN AN OXYGEN TOP-BLOWING CONVERTER Filed Sept.
  • This invention relates to a process for measuring the value of carbon content of a steel bath in an oxygen top-blowing converter during the blowing operation.
  • the inventors have discovered a method of simply and precisely measuring the value of carbon content of a steel bath in an oxygen top-blowing converter.
  • An object of the present invention is to provide a method of making the value of the carbon content of a steel bath in an oxygen top-blowing converter at the time of tapping steel therefrom coincide with a predetermined target value of the steel bath by measuring the value of carbon content which, in turn, is accomplished by detecting the amount of flow of waste gas issued from the converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas.
  • Another object of the present invention is to provide a method of precisely measuring the value of carbon content of a steel bath in the converter by detecting the amount of flow of waste gas issued from the converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas and further compensating for the amount of decarburization of the steel bath at the time when a peculiar change occurs in the decarburizing velocity.
  • FIGURE 1a is a diagram showing the relation between the value of carbon content of a steel bath and the time.
  • FIGURE 1b is a diagram showing the relation between the decarburizing velocity and the time.
  • FIGURE 1c is a diagram showing the relation between the decarburizing acceleration and the time.
  • FIGURE 2 is a system diagram of the present invention.
  • One of the practical applications of the present invention is as follows: From a waste gas issued from an oxygen top-blowing converter, the decarburizing velocity is detected by measuring the amount of flow of said waste gas issued from the converter and the compositions of said waste gas, then by integrating the thus detected decarburizing velocity, the amount of decarburization of a ice steel bath at a certain time after ignition may be calculated. Since the total amount of carbon content of the material charged in the converter may be calculated, the value of carbon content of the steel bath may be easily calculated by subtracting said amount of decarburization of the steel bath from the total amount of carbon content of the material.
  • (CO), (percent) and (CO (percent) designate the concentrations of carbon monoxide and carbon dioxide obtained by analyzing the waste gas caught at t, minutes after the ignition.
  • the amount of decarburization for t, minutes after the ignition, AC may be calculated, for instance, by continuously integrating the value given by the Formula 1 by means of an electronic integrating circuit or by carrying out an addition ofthe value of microtime by means of an electronic computer.
  • AC will be here calculated by integrating the value of each minute, as shown by the following formula:
  • the total amount of carbon, 2C (kg), contained in the charged steel-manufacturing material, which comprises, for instance, pig iron and scrap, may be .shown by the following formula:
  • the blowing operation may be automatically controlled. That is, the blowing operation may be stopped just immediately before the calculated value of carbon content will coincide with the predetermined target value thereof, whereby the end point of blowing may be scientifically and automatically found in combination with a computing control device.
  • FIGURE 11 shows an example of the change in the value of canbon content of the steel bath with the progress of blowing.
  • FIGURE 11) shows an example of the change in the decarburizing velocity, and
  • FIGURE an example of the change in the decarburizing acceleration.
  • the amount of decarburization AC (kg) at t, minutes after the ignition, as determined by the Formula 2 is represented by the area of the hatched part in FIGURE 1b. If the amount of AC, (kg) is to be expressed in the term of carbon content (percent) of the steel bath, it will be represented by the length of the segment A A, in FIGURE 1a.
  • the segment HA obtained by subtracting the segment A A from the segment m1, in FIGURE 1a represents the C (percent) of the Formula 4.
  • the value of carbon content of the steel bath may be automatically calculated at any time during the blowing operation.
  • the ratio of change in the decarburizing velocity at each moment that is, the decarburizing acceleration calculated from the decarburizing velocity
  • t t and t represent the time after ignition, at which the value of the decarburizing acceleration shows a change in the direction of its signal or a value greater that the predetermined one.
  • the values of the decarburizing velocity corresponding to the times t t and t in FIGURE 1b show the abrupt changes. According to runs made by the inventors it was discovered that, in general, the decarburizing velocity and decarburizing acceleration at any time are closely correlated with the carbon content of the steel bath at the corresponding time.
  • the value of the carbon content of the steel bath at the above mentioned times 1 t and t correspond to C (percent), C (percent) and C (percent), respectively, and these values show originally the specific inherent values according to the type of the converter, the blowing conditions and the kind of steel.
  • the decarburizing velocity is continuously measured during the blowing operation according to Formula 1 as above mentioned and then the decarburizing acceleration, that is, the ratio of change in the decarburizing velocity at each moment, is also continuously calculated from the decarburizing velocity, by means of, for instance, an electronic computor or an electronic circuit, whereby the times at which peculiar points in the curves of the decarburizing velocity and decarburizing acceleration appear, that is, t t t in FIGURE 11) or FIGURE 1c may be detected. If such points are detected, the exact value of the carbon content of the steel bath at the corresponding time may be obtained on the basis of the relation shown in FIGURE 1a which is predetermined according to the type of the converter, the blowing conditions and the kinds of the steel.
  • the decarburizing velocity calculated by Formula 1 is continuously differentiated by means of, for instance, an electronic computor or an electronic computing circuit to obtain the decarburizing acceleration, d c/dl If such a peculiar change occurs, in which the calculated value of the decarburizing acceleration exceeds a certain predetermined value or shows a change in the direction of its signal, an electric control signal is automatically issued from an electric control device at that time.
  • the predetermined standard value of carbon content of the steel bat-h [C] percent corresponding to the time, at which the above mentioned peculiar change is detected, is put into a coverting mechanism.
  • the total carbon weight 230 of the charged material iron and weight of the molten steel have already been memorized.
  • the amount of decarburization AC which includes errors obtained by integrating the Formula 2 are cancelled and replaced by the correct amount of decar-burization AC given by the Formula 5.
  • the value of carbon content incorrectly measured is compensated to the correct one of carbon content set by an electric control device or an electronic computor.
  • the subsequent integrating calculation may be continued by using this value as an initial value.
  • a process for tapping steel from an oxygen top-blowing converter said steel having a predetermined carbon content, which comprises measuring the amount of waste gas issued from said converter, measuring the amount of carbon monoxide and carbon dioxide contained in said waste gas, calculating the decarburization velocity from the amount of waste gas and the amount of carbon monoxide and carbon dioxide in said waste gas in accordance with the following formula wherein is the decarburizing velocity, F is the amount of waste gas, (CO) is the amount of carbon monoxide in said waste gas, and (CO is the amount of carbon dioxide in said waste gas; differentiating the said decarburization velocity thereby obtaining the decarburizing acceleration, noting any changes in the value of said decarburizing acceleration, calculating the carbon content of the steel at the time of said changes, and tapping the steel at the exact time the carbon centent of the steel reaches a predetermined value.
  • a process for tapping steel from an oxygen topblowing converter said steel having a predetermined carbon content, which comprises (a) measuring the amount of waste gas issued from said converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas,

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Description

July 4, 1967 PROCESS FOR MEASURING THE VALUE OF CARBON CONTENT OF A STEEL Decurburizing Value of curbo n conrenf -velocii'y -of the steel both Deccrburizing occelerurion (in kg/min) (in kg/min/sec) TAKAYOSHI OHTA ETAL 3,329,495
BATH IN AN OXYGEN TOP-BLOWING CONVERTER Filed Sept. 22, 1964 2 Sheets-Shed 1 I 1 2 f '3 (in minures) FIG. I (c) a E 1A: in 1 n 1 "flIr- Time (in minufes) lNVENTORS Tokcyoshi Ohio Tomohiko Aku'ku Minoru Nishiwoki Hideo Yoshizumi dad/W July 4, 1967 TAKAYOSHI OHTA ETAL PROCESS FOR MEASURING THE VALUE OF CARBON CONTENT OF A STEEL BATH IN AN OXYGEN TOP-BLOWING CONVERTER Filed Sept. 22, 1964 2 Sheets-Sheet 2 Waste gas F G 2 from converter Waste gas CO analyz r CO2 ono'yzer flow meter (coll i002" Fi I Recording I Recording Addition Carbon content of the steel bath Division Value of carbon content of the steel bath LTapping control step I liar change points Multiplication @ecarburizing velocity I Toftal carbon content 7 o the c arged raw material iron ZCO IRecordingI l I l l Integration Defferentiation l l I Amount of decar- Decarburizing bul'iZOtiOnACi acceleration Subtraction -I l 1 Recording l Converting Weight of the mechflnism molten steel Detection of pecu- Predetermined standard value of carbon content INVENTORS Takayoshi Ohta Tomohiko Akuta Minoru Nishiwaki Hideo Yoshizumi United States Patent PROCESS FOR MEASURING THE VALUE OF CAR- BUN CONTENT OF A STEEL BATH IN AN OXY- GEN TOP-BLOWING CONVERTER Takayoshi Ohta, Hikari, and Tomohiko Akuta, Minoru Nishiwaki, and Hideo Yoshizumi, Kitakyusliu, Japan, assignors to Yawata Iron & Steel Co., Ltd., and Yokoyama Engineering Co., Ltd., Tokyo, Japan, both Japanese corporations Filed Sept. 22, 1964, Ser. No. 398,337 Claims priority, application Japan, Sept. 26, 1963, 38/ 51,394 2 Claims. (Cl. 75-60) This invention relates to a process for measuring the value of carbon content of a steel bath in an oxygen top-blowing converter during the blowing operation.
In the operation of an oxygen top-blowing converter it is important to make the value of carbon content of the steel bath at the time of tapping steel therefrom coincide with the predetermined target value. However, in the conventional operating method the value of carbon content of the steel bath was estimated on the basis of the perception and experience of operators by their eye-measurements of flame and spark, because taking out the samples continuously from the steel bath for analysis during the blowing operation is almost impossible. Therefore, it was very diflicult to constantly hit the target value of carbon content of the steel bath at the time of tapping.
The inventors have discovered a method of simply and precisely measuring the value of carbon content of a steel bath in an oxygen top-blowing converter.
That is, by detecting the amount of flow of waste gas issued from the converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas, the scientific control of the tapping time of steel from the converter is made possible.
An object of the present invention is to provide a method of making the value of the carbon content of a steel bath in an oxygen top-blowing converter at the time of tapping steel therefrom coincide with a predetermined target value of the steel bath by measuring the value of carbon content which, in turn, is accomplished by detecting the amount of flow of waste gas issued from the converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas.
Another object of the present invention is to provide a method of precisely measuring the value of carbon content of a steel bath in the converter by detecting the amount of flow of waste gas issued from the converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas and further compensating for the amount of decarburization of the steel bath at the time when a peculiar change occurs in the decarburizing velocity.
Other objects of the present invention will be made clear by the following explanation and the accompanying drawings.
FIGURE 1a is a diagram showing the relation between the value of carbon content of a steel bath and the time.
FIGURE 1b is a diagram showing the relation between the decarburizing velocity and the time.
FIGURE 1c is a diagram showing the relation between the decarburizing acceleration and the time.
FIGURE 2 is a system diagram of the present invention.
One of the practical applications of the present invention is as follows: From a waste gas issued from an oxygen top-blowing converter, the decarburizing velocity is detected by measuring the amount of flow of said waste gas issued from the converter and the compositions of said waste gas, then by integrating the thus detected decarburizing velocity, the amount of decarburization of a ice steel bath at a certain time after ignition may be calculated. Since the total amount of carbon content of the material charged in the converter may be calculated, the value of carbon content of the steel bath may be easily calculated by subtracting said amount of decarburization of the steel bath from the total amount of carbon content of the material. However, as errors in measurements are liable to occur in the above mentioned process, it is necessary to correct such errors by detecting the moment when sharp changes in the decarburization velocity curve occur by measuring the decarburizing acceleration calculated from the decarburizing velocity and to compensate for the amount of the decarburization, which comprises errors, by a correct one which corresponds to the standard value of carbon content of the steel bath at that detected moment. In this way a very precise value of carbon content of a steel bath may be calculated.
In the operation of a converter, the carbon contained in the charged raw material will be oxidized by oxygen blowing, whereby carbon monoxide and carbon dioxide will be produced according to the following chemical reactions:
By the above reaction formulae, from one molecular weight (kg.) of carbon (12 kg.) there is produced one molecular weight (kg) of carbon monoxide or carbon dioxide, having a volume of 22.4 m. in the standard state, respectively. Therefore, on the basis of the above relations it is possible to calculate the amounts of carbon monoxide or carbon dioxide contained in waste gas issued from the oxygen top-blowing converter. Practically, if the flow rate of the waste gas produced by 0 blowing is measured, whereby, for instance, its value at t, minutes after the ignition is expressed as F (Nm. /hour), and the compositions of said waste gas obtained at the same moment are analytically determined, the decarburizing velocity at t, minutes after the ignition will be represented by the formula:
in which (CO), (percent) and (CO (percent) designate the concentrations of carbon monoxide and carbon dioxide obtained by analyzing the waste gas caught at t, minutes after the ignition.
Therefore, the amount of decarburization for t, minutes after the ignition, AC (kg), may be calculated, for instance, by continuously integrating the value given by the Formula 1 by means of an electronic integrating circuit or by carrying out an addition ofthe value of microtime by means of an electronic computer. For convenience of explanation, however, AC will be here calculated by integrating the value of each minute, as shown by the following formula:
Further, the total amount of carbon, 2C (kg), contained in the charged steel-manufacturing material, which comprises, for instance, pig iron and scrap, may be .shown by the following formula:
ZC -AC'i 1001 (W +W,,) (percent) wherein 1; is the yield of manufactured steel.
Thus, by measuring the value of carbon content of the steel bath at any moment during the blowing operation according to the Formula 4, the blowing operation may be automatically controlled. That is, the blowing operation may be stopped just immediately before the calculated value of carbon content will coincide with the predetermined target value thereof, whereby the end point of blowing may be scientifically and automatically found in combination with a computing control device.
The method of the present invention shall be explained more in detail with reference to the drawings. FIGURE 11: shows an example of the change in the value of canbon content of the steel bath with the progress of blowing. FIGURE 11) shows an example of the change in the decarburizing velocity, and FIGURE an example of the change in the decarburizing acceleration. The amount of decarburization AC (kg) at t, minutes after the ignition, as determined by the Formula 2, is represented by the area of the hatched part in FIGURE 1b. If the amount of AC, (kg) is to be expressed in the term of carbon content (percent) of the steel bath, it will be represented by the length of the segment A A, in FIGURE 1a. The segment HA; obtained by subtracting the segment A A from the segment m1, in FIGURE 1a represents the C (percent) of the Formula 4.
An embodiment of the method according to the present invention shall be explained with reference to FIGURE 2. At first, the calculations of addition and multiplication shown by the double enclosures in FIGURE 2 are carried out in order to determine the decarburizing velocity J 2 dt by the Formula 1 by using, for instance, an electronic computer or an electronic computing circuit, while inputing thereto the analysis values of the concentrations of carbon monoxide and carbon dioxide (CO), and (CO obtained by an analyzer respectively, and the amount of flow rate F of the waste gas continuously measured by a gas flow meter. Then, by integrating this decarburizing velocity, the amount of decarburization AC is determined. When the value of AC, is subtracted from the total amount of carbon 2C of the charged raw material iron as calculated in advance, and the thus obtained residue is divided by the amount of molten steel (W +W as calculated in advance, while taking the yield of steel into consideration, the value of carbon content of the steel bath may be automatically calculated at any time during the blowing operation.
According to experiments made by the inventors, however, it is found that, though the value of carbon content of the steel bath may be measured by the above mentioned method, many errors in measurements are apt to occur as, (a) the error ratio in measurement of carbon content in pig iron is usually at least 2%, resulting in more than *-0.06% error of carbon content value in the steel bath in the initial state, (b) even slight errors in the measurements of the waste gas by the flow meter and gas analyzer are apt to be gradually accumulated so as to produce large errors in the integrating calculation, (c) the carbon dioxide contained in the waste gas is apt to dissolve in cooling water which is used in adjusting the temperature of the waste gas, and ((1) gas leakage between the converter mouth and hood causes error in measuring waste gas fiow rate. Therefore, the total error in measuring decarburization AC by the above mentioned method becomes more than il0%, which is proved by the inventors experiments. This results in rendering the above mentioned method valueless in the actual operation, particularly for low carbon steel blowing in which the carbon content is less than 0.10% and the allowance of the value of carbon content of the steel bath requires such a high precision as less than :t0.0l% error, and therefore, a further process should be used for this purpose, as explained in the following.
In FIGURE 10, the ratio of change in the decarburizing velocity at each moment, that is, the decarburizing acceleration calculated from the decarburizing velocity, is represented. t t and t represent the time after ignition, at which the value of the decarburizing acceleration shows a change in the direction of its signal or a value greater that the predetermined one. The values of the decarburizing velocity corresponding to the times t t and t in FIGURE 1b show the abrupt changes. According to runs made by the inventors it was discovered that, in general, the decarburizing velocity and decarburizing acceleration at any time are closely correlated with the carbon content of the steel bath at the corresponding time. As shown in FIGURE 1a, the value of the carbon content of the steel bath at the above mentioned times 1 t and t correspond to C (percent), C (percent) and C (percent), respectively, and these values show originally the specific inherent values according to the type of the converter, the blowing conditions and the kind of steel.
Therefore, according to the method of the present invention the decarburizing velocity is continuously measured during the blowing operation according to Formula 1 as above mentioned and then the decarburizing acceleration, that is, the ratio of change in the decarburizing velocity at each moment, is also continuously calculated from the decarburizing velocity, by means of, for instance, an electronic computor or an electronic circuit, whereby the times at which peculiar points in the curves of the decarburizing velocity and decarburizing acceleration appear, that is, t t t in FIGURE 11) or FIGURE 1c may be detected. If such points are detected, the exact value of the carbon content of the steel bath at the corresponding time may be obtained on the basis of the relation shown in FIGURE 1a which is predetermined according to the type of the converter, the blowing conditions and the kinds of the steel.
This process step will be explained more in detail with reference to FIGURE 2. The decarburizing velocity calculated by Formula 1 is continuously differentiated by means of, for instance, an electronic computor or an electronic computing circuit to obtain the decarburizing acceleration, d c/dl If such a peculiar change occurs, in which the calculated value of the decarburizing acceleration exceeds a certain predetermined value or shows a change in the direction of its signal, an electric control signal is automatically issued from an electric control device at that time.
On the other hand, the predetermined standard value of carbon content of the steel bat-h [C] percent corresponding to the time, at which the above mentioned peculiar change is detected, is put into a coverting mechanism. In this converting mechanism, the total carbon weight 230 of the charged material iron and weight of the molten steel have already been memorized. And the calculation is carried out by the following formula to determine the correct amount of decarburization AC ECB-[C] percent weight of molten steel =AC (5) The amount of decarburization AC which includes errors obtained by integrating the Formula 2 are cancelled and replaced by the correct amount of decar-burization AC given by the Formula 5.
Thus, the value of carbon content incorrectly measured, is compensated to the correct one of carbon content set by an electric control device or an electronic computor. The subsequent integrating calculation may be continued by using this value as an initial value. Thus, by detecting the time of change in the decarburizing velocity by means of the decarburizing acceleration obtained by differentiating the decarburizing velocity and inputting the standard value of carbon content of the steel bath at that time, at which such a change is detected, into a converting mechanism, it is possible to amend such errors as the analyzing error of the carbon content in raw material, accumulated error by the integrating calculation and gas analysing error by dissolution of carbon dioxide.
Thus, a very precise value of carbon content of the steel bath may be measured by repeating this procedure several times during the process of the blowing operation.
It is also possible to amend the errors by detecting the times of changes t t and t by means of the decarburizing velocity as shown in FIGURE 1b and putting into the converting mechanism the standard Value of carbon content corresponding to such detected time.
Although the above mentioned explanation of this invention is related to the continuous precise measuring process of carbon content of steel bat-h during the blowing operation, combining the amending method of carbon content of steel at peculiar change points of the decarburizing reaction to continuous calculation of car-bon content of steel by integration, it is obviously possible to apply the detecting method of carbon of steel at separate peculiar change points independently.
What We claim is:
1. A process for tapping steel from an oxygen top-blowing converter, said steel having a predetermined carbon content, which comprises measuring the amount of waste gas issued from said converter, measuring the amount of carbon monoxide and carbon dioxide contained in said waste gas, calculating the decarburization velocity from the amount of waste gas and the amount of carbon monoxide and carbon dioxide in said waste gas in accordance with the following formula wherein is the decarburizing velocity, F is the amount of waste gas, (CO) is the amount of carbon monoxide in said waste gas, and (CO is the amount of carbon dioxide in said waste gas; differentiating the said decarburization velocity thereby obtaining the decarburizing acceleration, noting any changes in the value of said decarburizing acceleration, calculating the carbon content of the steel at the time of said changes, and tapping the steel at the exact time the carbon centent of the steel reaches a predetermined value.
2. A process for tapping steel from an oxygen topblowing converter, said steel having a predetermined carbon content, which comprises (a) measuring the amount of waste gas issued from said converter and the amounts of carbon monoxide and carbon dioxide contained in said waste gas,
(b) calculating the decarburization velocity from the amount of Waste .gas and the amount of carbon monoxide and carbon dioxide in said waste gas in accordance with the formula set forth in claim 1,
(c) differentiating the decarburization velocity to thereby obtain the decarburizing acceleration,
(d) noting the times at which peculiar change points appear in the decarburizing acceleration,
(e) calculating the carbon content of the steel at the time of said changes,
(f) calculating the correct amount of decarburization in accordance with the following formula 2C [C] percent X weight of molten steel=ACf wherein EC is the total carbon weight of the charged material iron and [C] percent is predetermined standard value of carbon content of the steel bath corresponding to the time the above-mentioned peculiar change is detected,
(g) calculating the amount of decarburization was AG,
by integrating the decarburizing velocity,
(h) amending the AG, by the said correct amount of decarburization AC and (i) tapping the steel at the exact time the carbon content of the steel reaches a pre-determined value.
References Cited UNITED STATES PATENTS 2,595,792 5/1952 Jordan -60 3,218,842 "ll/1965 Ludwig et al. 73-23 RICHARD C. QU-EISSER, Primary Examiner.
J. FISHER, C. I. MCCLELLAND,
Assistant Examiners.

Claims (1)

1. A PROCESS FOR TAPPING STEEL FROM AN OXYGEN TOP-BLOWING CONVERTER, SAID STEEL HAVING A PREDETERMINED CARBON CONTENT, WHICH COMPRISES MEASURING THE AMOUNT OF WASTE GAS ISSUED FROM SAID CONVERTER, MEASURING THE AMOUNT OF CARBON MONOXIDE AND CARBON DIOXIDE CONTAINED IN SAID WASTE GAS, CALCULATING THE DECARBURIZATION VELOCITY FROM THE AMOUNT OF WASTE GAS AND THE AMOUNT OF CARBON MONOXIDE AND CARBON DIOXIDE IN SAID WASTE GAS IN ACCORDANCE WITH THE FOLLOWING FORMULA -(DC/DT) = FI(((CO)+(CO2))/100) WHEREIN -(DC/DT) IS THE DECARBURIZING VELOCITY, F1 IS THE AMOUNT OF WASTE GAS, (CO) IS THE AMOUNT OF CARBON MONOXIDE IN SAID
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Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3432288A (en) * 1966-06-29 1969-03-11 Allegheny Ludlum Steel Process control of top-blown oxygen converter
US3450867A (en) * 1966-03-14 1969-06-17 Leeds & Northrup Co Estimated tap temperature calculator for basic oxygen furnace
US3463631A (en) * 1963-12-03 1969-08-26 Siderurgie Fse Inst Rech Method and arrangement for determining the oxidation reactions during refining of metals
US3475599A (en) * 1965-03-30 1969-10-28 Leeds & Northrup Co Process measurement system for basic oxygen refining of steel
US3485619A (en) * 1965-10-04 1969-12-23 Beteiligungs & Patentverw Gmbh Method of automatic control and adjustment of oxygen blowing processes
US3489518A (en) * 1966-11-02 1970-01-13 Koppers Co Inc Carbon determination method and apparatus
US3500029A (en) * 1967-08-17 1970-03-10 Leeds & Northrup Co Charge computer for basic oxygen furnace
US3510262A (en) * 1966-09-16 1970-05-05 United States Steel Corp Carbon analyzing system
US3520657A (en) * 1965-12-27 1970-07-14 Dravo Corp Method and apparatus for the analysis of off-gases in a refining process
US3528800A (en) * 1966-02-14 1970-09-15 Leeds & Northrup Co Optimized blowing control for basic oxygen furnaces
US3533778A (en) * 1966-04-20 1970-10-13 Centre Nat Rech Metall Automatic control of pig iron refining
US3534143A (en) * 1968-10-25 1970-10-13 Westinghouse Electric Corp Computer control of metal treatment furnace operation
US3540879A (en) * 1967-06-27 1970-11-17 Westinghouse Electric Corp Method for controlling phosphorus removal in a basic oxygen furnace
US3607230A (en) * 1969-01-21 1971-09-21 Koppers Co Inc Process for controlling the carbon content of a molten metal bath
US3619174A (en) * 1965-11-27 1971-11-09 Sumitomo Metal Ind Method for controlling the carbon content in and/or the temperature of the steel
US3640119A (en) * 1966-02-14 1972-02-08 Leeds & Northrup Co Carbon content measurement in a basic oxygen furnace
US3653650A (en) * 1968-12-27 1972-04-04 Yawata Iron & Steel Co Method of controlling the exhaust gas flow volume in an oxygen top-blowing converter
US3720404A (en) * 1967-06-27 1973-03-13 Westinghouse Electric Corp System for controlling carbon removal in a basic oxygen furnace
US3773497A (en) * 1972-03-02 1973-11-20 Steel Corp Steelmaking
US3779744A (en) * 1972-04-05 1973-12-18 Westinghouse Electric Corp Modification and improvement to dynamic bof control
US3816720A (en) * 1971-11-01 1974-06-11 Union Carbide Corp Process for the decarburization of molten metal
US4073619A (en) * 1974-10-28 1978-02-14 British Steel Corporation Sampling gas for analysis
US4187541A (en) * 1977-06-13 1980-02-05 Institut Kibernetiki Akademii Nauk Ukrainskoi Ssr Digital analyzer for determining liquidus temperature of metals and alloys
US4190888A (en) * 1977-06-13 1980-02-26 Institut Kibernetiki Akademii Nauk Ukrainskoi S S R Digital device for determining carbon content in iron-carbon melts
US4198679A (en) * 1977-06-28 1980-04-15 Institut Kibernetiki Akademii Nauk Ukrainskoi Ssr Method and device for discriminating thermal effect of phase transformation of metals and alloys in the process of their cooling
CN113009103A (en) * 2019-12-19 2021-06-22 上海梅山钢铁股份有限公司 On-line calculation method for carbon content of converter mouth
CN113106188A (en) * 2021-04-09 2021-07-13 福建三宝钢铁有限公司 Preparation method of HRB500E niobium-containing titanium alloy deformed steel bar

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JPS5442323A (en) * 1977-09-10 1979-04-04 Nisshin Steel Co Ltd Control procedure of steel making process using mass spectormeter
CN113076505B (en) * 2020-01-05 2024-06-04 上海梅山钢铁股份有限公司 Converter molten steel decarburization rate calculation method

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Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3463631A (en) * 1963-12-03 1969-08-26 Siderurgie Fse Inst Rech Method and arrangement for determining the oxidation reactions during refining of metals
US3475599A (en) * 1965-03-30 1969-10-28 Leeds & Northrup Co Process measurement system for basic oxygen refining of steel
US3485619A (en) * 1965-10-04 1969-12-23 Beteiligungs & Patentverw Gmbh Method of automatic control and adjustment of oxygen blowing processes
US3619174A (en) * 1965-11-27 1971-11-09 Sumitomo Metal Ind Method for controlling the carbon content in and/or the temperature of the steel
US3520657A (en) * 1965-12-27 1970-07-14 Dravo Corp Method and apparatus for the analysis of off-gases in a refining process
US3528800A (en) * 1966-02-14 1970-09-15 Leeds & Northrup Co Optimized blowing control for basic oxygen furnaces
US3640119A (en) * 1966-02-14 1972-02-08 Leeds & Northrup Co Carbon content measurement in a basic oxygen furnace
US3450867A (en) * 1966-03-14 1969-06-17 Leeds & Northrup Co Estimated tap temperature calculator for basic oxygen furnace
US3533778A (en) * 1966-04-20 1970-10-13 Centre Nat Rech Metall Automatic control of pig iron refining
US3432288A (en) * 1966-06-29 1969-03-11 Allegheny Ludlum Steel Process control of top-blown oxygen converter
US3510262A (en) * 1966-09-16 1970-05-05 United States Steel Corp Carbon analyzing system
US3489518A (en) * 1966-11-02 1970-01-13 Koppers Co Inc Carbon determination method and apparatus
US3720404A (en) * 1967-06-27 1973-03-13 Westinghouse Electric Corp System for controlling carbon removal in a basic oxygen furnace
US3540879A (en) * 1967-06-27 1970-11-17 Westinghouse Electric Corp Method for controlling phosphorus removal in a basic oxygen furnace
US3500029A (en) * 1967-08-17 1970-03-10 Leeds & Northrup Co Charge computer for basic oxygen furnace
US3534143A (en) * 1968-10-25 1970-10-13 Westinghouse Electric Corp Computer control of metal treatment furnace operation
US3653650A (en) * 1968-12-27 1972-04-04 Yawata Iron & Steel Co Method of controlling the exhaust gas flow volume in an oxygen top-blowing converter
US3607230A (en) * 1969-01-21 1971-09-21 Koppers Co Inc Process for controlling the carbon content of a molten metal bath
US3816720A (en) * 1971-11-01 1974-06-11 Union Carbide Corp Process for the decarburization of molten metal
US3773497A (en) * 1972-03-02 1973-11-20 Steel Corp Steelmaking
US3779744A (en) * 1972-04-05 1973-12-18 Westinghouse Electric Corp Modification and improvement to dynamic bof control
US4073619A (en) * 1974-10-28 1978-02-14 British Steel Corporation Sampling gas for analysis
US4187541A (en) * 1977-06-13 1980-02-05 Institut Kibernetiki Akademii Nauk Ukrainskoi Ssr Digital analyzer for determining liquidus temperature of metals and alloys
US4190888A (en) * 1977-06-13 1980-02-26 Institut Kibernetiki Akademii Nauk Ukrainskoi S S R Digital device for determining carbon content in iron-carbon melts
US4198679A (en) * 1977-06-28 1980-04-15 Institut Kibernetiki Akademii Nauk Ukrainskoi Ssr Method and device for discriminating thermal effect of phase transformation of metals and alloys in the process of their cooling
CN113009103A (en) * 2019-12-19 2021-06-22 上海梅山钢铁股份有限公司 On-line calculation method for carbon content of converter mouth
CN113106188A (en) * 2021-04-09 2021-07-13 福建三宝钢铁有限公司 Preparation method of HRB500E niobium-containing titanium alloy deformed steel bar

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DE1433701A1 (en) 1968-11-28
GB1087053A (en) 1967-10-11
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AT278881B (en) 1970-02-10
BE653544A (en) 1965-01-18

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