US3780581A - Method and apparatus for determining the depth of submerged lances and the like - Google Patents

Method and apparatus for determining the depth of submerged lances and the like Download PDF

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Publication number
US3780581A
US3780581A US00172697A US3780581DA US3780581A US 3780581 A US3780581 A US 3780581A US 00172697 A US00172697 A US 00172697A US 3780581D A US3780581D A US 3780581DA US 3780581 A US3780581 A US 3780581A
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United States
Prior art keywords
lance
pressure
conduit
bath
gas
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Expired - Lifetime
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US00172697A
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English (en)
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T Acre
F Gimbel
S Ramacheandran
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Allegheny Ludlum Corp
Pittsburgh National Bank
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Allegheny Ludlum Industries Inc
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Assigned to ALLEGHENY LUDLUM CORPORATION reassignment ALLEGHENY LUDLUM CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). 8-4-86 Assignors: ALLEGHENY LUDLUM STEEL CORPORATION
Assigned to PITTSBURGH NATIONAL BANK reassignment PITTSBURGH NATIONAL BANK SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ALLEGHENY LUDLUM CORPORATION
Assigned to PITTSBURGH NATIONAL BANK reassignment PITTSBURGH NATIONAL BANK ASSIGNMENT OF ASSIGNORS INTEREST. RECORDED ON REEL 4855 FRAME 0400 Assignors: PITTSBURGH NATIONAL BANK
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Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D19/00—Arrangements of controlling devices
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4606—Lances or injectors
    • C21C5/4613—Refractory coated lances; Immersion lances
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4606—Lances or injectors
    • C21C5/462—Means for handling, e.g. adjusting, changing, coupling
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4673—Measuring and sampling devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
    • F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
    • F27B3/22—Arrangements of air or gas supply devices
    • F27B3/225—Oxygen blowing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/18—Door frames; Doors, lids, removable covers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D21/00—Arrangements of monitoring devices; Arrangements of safety devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C13/00—Surveying specially adapted to open water, e.g. sea, lake, river or canal
    • G01C13/008—Surveying specially adapted to open water, e.g. sea, lake, river or canal measuring depth of open water

Definitions

  • ABSTRACT Method and apparatus for determining the depth of a submerged article with the use of a pressure probe, and in particular the depth of a submerged lance used to deliver a gaseous reaction agent to a metallic bath The probe is adjacent or within a conduit delivering the gaseous reaction agent to the bath.
  • the pressure at the probe is compared with that above the bath, the difference between the two pressures being propor- 52 us. 01.
  • 73/302 tional dePth- The System can be used in installatms [51] Int CL G0 23/14 where the pressure at the surface of the bath is atmo- [58] Field of Search 73/302 301' sPeric Pmure in cases where the 266/34 L, 2 surface is evacuated as in vacuum decarburization of stainless steels and the like.
  • the [56] References Cited probe is usually pressurized to prevent clogging of the UNITED STATES PATENTS tip.
  • the ambient pressure at the tip of the probe is compared with that above the surface ,47,t23g(2) 9/1947 Peterson 1.
  • the lance tip of a gas injection lance should be immersed in the metal bath. Furthermore, the depth of immersion is critical. When the lance is one inch or more above the bath or is immersed inches or more, splashing and slopping of the metal bath are noticeably increased. Furthermore, when the lance tip is immersed more than six inches below the liquid level of the metal bath, severe erosion of the lance occurs.
  • the desired depth of the lance tip is preferably no greater than two inches.
  • a method and apparatus are provided for determining the depth of the bottom of a gas lance in a molten metal bath by providing a conduit or probe having a tip terminating at the bottom of the lance and by measuring the pressure difference between that in the probe and the pressure above the surface of the molten metal bath.
  • a conduit having a lower tip essentially coincident with the bottom of a gas-issuing lance in a molten metal bath and manometer means for comparing the pressure in the conduit with the pressure of the atmosphere above the surface of the bath whereby the depth of the lower tip and the bottom of the lance can be determined from a consideration of the difference in pressures in the conduit and above the surface of the bath.
  • the pressure differential is the true measure of the depth of immersion of the bottom of the lance since the pressure within the aforesaid conduit adjacent the lance varies as a function of the hydrostatic pressure of the molten metal at the tip of the conduit or probe.
  • FIG. 1 is a schematic illustration of one embodiment of the invention wherein the gas above the surface of a metallic bath is at atmospheric pressure;
  • FIG. 2 is a cross-sectional view of the lance shown in FIG. 1, taken substantially along line IIII of FIG. 1;
  • FIGS. 3 and 4 are cross-sectional views, similar to that of FIG. 2, showing alternative embodiments of the lance construction of the invention
  • FIG. 5 is a plot showing the manner in which pressure differential varies as depth increases.
  • FIG. 6 is a schematic illustration of an embodiment of the invention as applied to vacuum decarburization apparatus.
  • a reaction vessel 10 comprising an outer metallic lining 12 provided on its interior surface with a refractory lining 14.
  • the vessel 10 has an open upper end 18 which receives a gas-delivery lance 20,
  • the lance 20 comprises a metallic pipe or tube 22, the lower portion of which is surrounded by a refractory jacket 24.
  • Passing through the wall of the pipe 22 is a second conduit 26 connected to or integral with a probe 28 which extends downwardly through the pipe 22 and has a lower tip 30 coplanar with and terminating at the bottom 32 of the lance 20.
  • the probe 28 should be made of similar material as the consumingportion so that the probe consumes at about the same rate. If the lance is nonconsumable, the probe should also be non-consumable. Normally, both the pipe 22 and the probe 28 will be formed from steel. It has been found from actual trials that the probe is preferably positioned adjacent and in abutment with the inside wall of the pipe 22 as shown in FIG. 2. With this arrangement, the pipe 22 will burn back or be consumed at about the same rate as the probe 28, thereby insuring that the bottom or tip of the probe 28 will be coplanar with the bottom of the lance 20 at all times.
  • FIGS. 3 and 4 Alternative embodiments of the lance 20, while not preferred, are shown in FIGS. 3 and 4.
  • the probe 28' is concentric with the pipe 22' which is surrounded by a refractory jacket 24'.
  • the probe 28" is imbedded within the refractory jacket 24" surrounding the main gas delivery pipe 22".
  • the arrangements of FIGS. 3 and 4, while workable, are not considered to be as reliable as the arrangement shown in FIG. 2 for insuring that the probe will burn back or be consumed at the same rate as the main gas delivery conduit, such as pipe-22.
  • the upper end of the main gas delivery pipe 22 is connected to a source of gas under pressure.
  • this gas is oxygen which is used to burn out carbon and other impurities within the melt 16.
  • the lance tip or bottom 32 should be immersed within the molten metal bath 16; however the depth of immersion is critical. Rapid erosion of the lance occurs when the tip is six inches or more beneath the level of the bath. Minimum splashing and slopping occur without incurring excessive erosion when the lance is no more than about two inches beneath the surface.
  • the probe 28 within the pipe 22 is connected through conduit 26 and valve 36 to one side of a manometer 38.
  • the other side of the manometer 38 is open to the atmosphere. Consequently, it is at the same pressure as the air above the surface of the molten metal bath l6.
  • a pressurized gas source 40 can be connected through a pressure regulator 42 and valve 44 to the conduit 26.
  • the gas from source 40 is preferably an inert gas; however air or even oxygen can be used.
  • the differential pressure reading observed with the manometer 38 will be greater than i in the case where the probe is not pressurized; however the pressure differential 'is still proportional to the depth of the bottom of the lance; and the manometer 38 can be calibrated to show this depth.
  • a pressurized gas source 45 is connected through a valve 46 to the probe 28, the valve 46 being intermittently opened and closed by means of a pulsing mechanism 48.
  • the pulsed gas can then be made to flow into the conduit 26 through valve 50, with valve 44 closed and valve 36 open.
  • the pressure differential observed on the manometer 38 will be that between the pressure within the pipe 22 and atmospheric pressure,
  • a pulse will be applied to the probe, for example, only once every minute such that a reading on the manometer 38 between pulses can be determined.
  • valve 36 is connected to a differential pressure cell 54 which produces an output signal on lead 56 proportional to the difference in pressure between that in probe 28 and atmospheric pressure.
  • a differential pressure cell 54 which produces an output signal on lead 56 proportional to the difference in pressure between that in probe 28 and atmospheric pressure.
  • the differential pressure cell can be used to generate an electrical signal whose average magnitude represents depth as indicated on the meter 60, for example, while the movement of the mercury in the manometer 38 acts as an excellent indicator of the splashing and slopping of the bath during injection. Since the manometer 38 and differential pressure cell can be used interchangeably, the term manometer means" as used in the claims herein means either.
  • FIG. 5 A plot of pressure differential versus depth immersion is shown in FIG. 5.
  • the pressure differential is relatively low.
  • the pressure differential increases along a straight line.
  • the pressure differential rises linearly as depth increases, but at a much higher rate than when passing'through slag, which is of lower density.
  • FIG. 6 another embodiment of the invention is shown as. applied to vacuum decarburization.
  • a molten metal bath 62 is again positioned within a refractory-lined vessel 64.
  • the vessel 64 is provided with a dome-shaped cover 66 connected to the vessel 64 through an annular sealing arrangement 68.
  • the dome-shaped cover 66 is connected through conduit 70 to an evacuating pump, not shown, such that the space above the liquid metal bath 62 will be evacuated.
  • Vacuum decarburization of this type is employed in certain cases, particularly with stainless steels and the like, since the activity of carbon (i.e., the rate at which it combines with oxygen to form carbon monoxide) is inversely proportional to the pressure above they bath.
  • the refining oxygen passing through the lance 20 preferentially combines with carbon rather than with chromium or other desired alloying constituents.
  • the lance in the embodiment of FIG. 6 is essentially the same as that shown in FIG. 1 and, accordingly, elements of FIG. 6 which correspond to those of FIG. 1 are identified by like reference numerals.
  • the pipe 22 passes upwardly through a seal 72 in the dome-shaped cover 66.
  • the conduit 26 is again connected to one end of a manometer 38; however in this case the other side of the manometer is connected through conduit 74 to the evacuated space above the bath 62.
  • the pressure above the bath 62 in the embodiment of FIG. 6 will vary due to the evolution of gases and/or splashing and slopping of the metal bath. If the probe 28 is to be constantly pressurized, therefore, it will be necessary to supply it with a source of gas 76 me constant volumetric flow rate.
  • This source of gas can be connected to conduit 26, for example, through valve 78.
  • valve 80 will be open and valve 78 closed.
  • Pressurized gas from gas source 82 then passes through pulsing valve 84 connected to pulsing mechanism 86 and thence through valve 80 to the conduit 26.
  • the probe need be pulsed only about once every minute.
  • an average reading of the manometer 38 can be derived to determine the depth of the lance.
  • the differential pressure cell 54 of FIG. 1 can be used together with an averaging or integrating circuit in a direct read-out meter, such as meter 60.
  • a gas-issuing lance immersed in a molten metal bath means for forcing a gas through said lance and into the molten metal bath, a conduit having a lower tip essentially coincident with the bottom of said lance when immersed in a molten metal bath and subjected to the pressure of the gas passing through the lance at the tip of the lance when it is so immersed, a source of gas under pressure, means for intermittently connecting said source of gas under pressure to said conduit whereby the conduit is continually pulsepressurized, and manometer means for comparing the pressure in said conduit with the pressure of gas above the surface of said bath while said conduit is continually pulse-pressurized whereby the depth of said lower tip and the bottom of said lance can be determined from a consideration of the difference in pressures in the conduit and above the surface of the bath.
  • a gas-issuing lance immersed in a molten metal bath means for forcing a gas through said lance and into the molten metal bath, a conduit having a lower tip essentially coincident with the bottom of said lance when immersed in a molten metal bath and subjected to the pressure of the gas passing through the lance at the tip of the lance when it is so immersed, manometer means for comparing the pressure in said conduit with the pressure of gas above the surface of said bath whereby the depth of said lower tip and the bottom of said lance can be determined from a consideration of the difference in pressures in the conduit and above the surface of the bath, said manometer means including a differential pressure cell for producing an electrical output signal proportional to the difference in pressure between that in said conduit and the pressure above said surface of the bath, means for integrating said electrical signal, and meter means connected to said integrating means for indicating said difference in pressure.
  • a gas-issuing lance immersed in a molten metal bath means for forcing a gas through said lance and into the molten metal bath, a conduit having a lower tip essentially coincident with the bottom of said lance when immersed in a molten metal bath and subjected to the pressure of the gas passing through the lance at the tip of the lance when it is so immersed, said lance and said conduit both being consumable in the molten metal bath, the conduit being positioned adjacent and in abutment with the inside wall of said lance whereby the conduit and lance will be consumed in the molten metal bath at substantially the same rate, and manometer means for comparing the pressure in said conduit with the pressure of gas above the surface of said bath whereby the depth of said lower tip and the bottom of said lance can be determined from a consid eration of the difference in pressures in the conduit and above the surface of the bath.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
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US00172697A 1971-08-18 1971-08-18 Method and apparatus for determining the depth of submerged lances and the like Expired - Lifetime US3780581A (en)

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US (1) US3780581A (fr)
JP (1) JPS4829613A (fr)
AU (1) AU4464872A (fr)
BE (1) BE787679A (fr)
DE (1) DE2239216A1 (fr)
ES (1) ES405576A1 (fr)
FR (1) FR2150172A5 (fr)
GB (1) GB1356225A (fr)
IT (1) IT964001B (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969942A (en) * 1975-08-11 1976-07-20 Hope Henry F Liquid level responsive apparatus
US4102190A (en) * 1977-04-07 1978-07-25 Bethlehem Steel Corporation Method and apparatus for determining the weight of slag on a bath of molten metal
US4111044A (en) * 1976-12-10 1978-09-05 Mcclure Charles A Flow monitoring
US4359211A (en) * 1979-07-16 1982-11-16 Arbed S.A. Method of and apparatus for measuring level and characteristics of a slag layer overlying a metallurgical metal
US4407159A (en) * 1981-01-19 1983-10-04 Wytaniec Casimir S Apparatus and method for detecting an interface from a remote location
US4694692A (en) * 1986-06-04 1987-09-22 Technical Oil Tools Corporation Drilling fluid density measurement system
US5052222A (en) * 1990-11-05 1991-10-01 Teledyne Exploration Multiple-unit water depth sensor system
US5669956A (en) * 1993-06-11 1997-09-23 Midwest Instrument Co., Inc. Apparatus and method for molten metal depth detection
CN101936660A (zh) * 2010-09-15 2011-01-05 中国恩菲工程技术有限公司 喷枪控制装置
CN105247079A (zh) * 2013-03-25 2016-01-13 奥钢联钢铁公司 用于确定反应过程的反应数据的方法和吹管

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0045658A1 (fr) * 1980-08-06 1982-02-10 British Steel Corporation Procédé pour commander un passage d'amenée de gaz
JPS60160256U (ja) * 1984-04-03 1985-10-24 トヨタ自動車株式会社 自動車のドアガラスウエザストリツプ
JP5324832B2 (ja) * 2008-06-13 2013-10-23 株式会社タクマ 灰溶融炉のレベル測定方法及びレベル測定装置
CN116447877B (zh) * 2023-06-17 2023-08-29 河北和和能源科技有限公司 一种压力储能式加热炉炉门升降装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1359014A (en) * 1920-06-01 1920-11-16 Alexander William Depth, draft, and displacement indicator
US2213485A (en) * 1938-06-09 1940-09-03 Victor H Conley Liquid level indicator
US2427690A (en) * 1945-11-26 1947-09-23 Carl W Peterson Liquid measuring system
US3130252A (en) * 1959-02-20 1964-04-21 Arbed Lances for treatment of metal baths

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1359014A (en) * 1920-06-01 1920-11-16 Alexander William Depth, draft, and displacement indicator
US2213485A (en) * 1938-06-09 1940-09-03 Victor H Conley Liquid level indicator
US2427690A (en) * 1945-11-26 1947-09-23 Carl W Peterson Liquid measuring system
US3130252A (en) * 1959-02-20 1964-04-21 Arbed Lances for treatment of metal baths

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969942A (en) * 1975-08-11 1976-07-20 Hope Henry F Liquid level responsive apparatus
US4111044A (en) * 1976-12-10 1978-09-05 Mcclure Charles A Flow monitoring
US4102190A (en) * 1977-04-07 1978-07-25 Bethlehem Steel Corporation Method and apparatus for determining the weight of slag on a bath of molten metal
US4359211A (en) * 1979-07-16 1982-11-16 Arbed S.A. Method of and apparatus for measuring level and characteristics of a slag layer overlying a metallurgical metal
US4407159A (en) * 1981-01-19 1983-10-04 Wytaniec Casimir S Apparatus and method for detecting an interface from a remote location
US4694692A (en) * 1986-06-04 1987-09-22 Technical Oil Tools Corporation Drilling fluid density measurement system
US5052222A (en) * 1990-11-05 1991-10-01 Teledyne Exploration Multiple-unit water depth sensor system
US5669956A (en) * 1993-06-11 1997-09-23 Midwest Instrument Co., Inc. Apparatus and method for molten metal depth detection
CN101936660A (zh) * 2010-09-15 2011-01-05 中国恩菲工程技术有限公司 喷枪控制装置
CN105247079A (zh) * 2013-03-25 2016-01-13 奥钢联钢铁公司 用于确定反应过程的反应数据的方法和吹管
JP2016514769A (ja) * 2013-03-25 2016-05-23 フォエスタルピネ スタール ゲーエムベーハー 槍および反応経過の反応データを決定するための方法
US10126286B2 (en) 2013-03-25 2018-11-13 Voestalpine Stahl Gmbh Lance and method for determining reaction data of the course of a reaction
CN105247079B (zh) * 2013-03-25 2019-07-09 奥钢联钢铁公司 用于确定反应过程的反应数据的方法和吹管

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ES405576A1 (es) 1975-08-01
AU4464872A (en) 1974-02-07
IT964001B (it) 1974-01-21
JPS4829613A (fr) 1973-04-19
GB1356225A (en) 1974-06-12
FR2150172A5 (fr) 1973-03-30
BE787679A (fr) 1973-02-19
DE2239216A1 (de) 1973-05-03

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