US3666449A - Method for the introduction of volatile additives into a melt - Google Patents
Method for the introduction of volatile additives into a melt Download PDFInfo
- Publication number
- US3666449A US3666449A US793065*A US3666449DA US3666449A US 3666449 A US3666449 A US 3666449A US 3666449D A US3666449D A US 3666449DA US 3666449 A US3666449 A US 3666449A
- Authority
- US
- United States
- Prior art keywords
- melt
- magnesium
- vessel
- additive
- molten metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- 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
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/10—Making spheroidal graphite cast-iron
Definitions
- the vapor bubbles formed ascend through the melt with such a size and in such a number that at least a portion of the bubbles escape from the surface of the melt.
- the vapor bubbles have a great surface area to provide, for example with magnesium, a yield of at least 30% and preferably more than 40% of the additive in the melt while the velocity of the ascending vapor bubbles is such as to produce a flushing action on the melt resulting in a reduction of the reaction products and residual undesirable impurities in the melt.
- the present invention relates to an improved method for the introduction of volatile or vaporizable additives into a melt, especially magnesium, into an iron-carbon melt, in which the vaporization is initiated by a tilting movement of the treatment vessel whereby the volatile additives are immersed beneath the surface of the melt, and further, wherein the speed of vaporization is retarded by means of a receiving compartment for the additives which are to be vaporized, such receiving compartment being equipped with openings directed into the interior of the treatment vessel and relates further to the use of the same for the production for various materials.
- magnesium as well as also other elements of the earth alkaline group and the group of the rare earths, causes, in known manner, a separation of the graphite in spherical form during solidification and/or subsequent heat treatment, and therefore results in improved mechanical properties.
- magnesium is introduced in the form of key alloys or hardeners with a magnesium content of to 30% into the melt which is to be treated, since the vapor pressure is reduced in accordance with the dilution.
- the yield is considerably increased due to the arrangement of a number of small openings, whereby the melt does not enter into the chamber or compartment containing the magnesium, rather the heat required for vaporization is delivered by conducting heat through the walls of the chamber.
- the flushing effect is practically lost.
- EX still further object of this invention is the provision of a method for the addition of other materials such as fluxing agents and carbon to the melt simultaneously with the addition of the vaporizable materials.
- the size of the vapor bubbles is chosen to be such that there results a sufficiently great reaction surface of the vapor bubbles ascending in the melt whereby there is obtained a favorable yield of the additives introduced into the melt, for instance, a magnesium yield in iron-carbon melts at the usual treatment temperature of at least 30% and preferably above 40%.
- the invention method is characterized by the fact that the vapor bubbles of the vaporizing additives are permitted to ascend through the melt with such a size and in such a number that, on the one hand, there occurs as extensive as possible absorption or reception of the resulting vapor by the melt and, on the other hand, a favorable flushing action for separating reaction products between the melt and the resulting vapor.
- the additives During the introduction of the additives into the melt, the same can be simultaneously subjected to a circulatory movement.
- the invention is also concerned with the provision of an improved tiltable treatment vessel for car rying out the aforesaid inventive process.
- This tiltable treatment vessel is manifested by the fact that it possesses at least one rigidly-mounted receiving compartment for the additives which compartment can be charged from the outside, that is externally of the vessel.
- This receiving compartment is arranged at least at 'a portion of the base surface of the interior of the ladle or vessel when the vessel is tilted to its treatment or vertically-extending position. Yet, the interior or inner chamber of the receiving compartment does not communicate with the melt when the vessel is in its filling or horizontally-extending position.
- the compartment includes a number of openings directed towards the interior of the treatment vessel, which openings are arranged and constructed in such a fashion that the melt passes into the compartment from the treatment vessel through at least some of the openings when the vessel is in its treatment position to vaporize the vaporizable additives with a certain speed and then passes back through at least some of the openings from the compartment into the interior or inner chamber of the treatment vessel.
- the techniques hereof may be used for treating cast iron or malleable cast iron melts which have been molten in an acidic process without prior desulfurization, with technically pure magnesium or alloys containing large quantities of magnesium. Further, these techniques may be used for the production of cast iron with a carbon content of 2.5 to 3.8% carbon, as well as for the production of gray cast iron and cast iron with vermicular graphite.
- the magnesium yield amounts to at least 30% and preferably, more than 40%.
- FIG. 1 schematically illustrates an exemplary embodiment of a tiltable treatment vessel according to this invention in its filling or horizontally extending position
- FIG. 2 depicts the tiltable vessel shown in FIG. 1 in its treatment or vertically extending position.
- the treatment vessell is lined with refractory material and is filled while in its horizontally extending position with melt 2 to such an extent that the receiving compartment or chamber 3, which can be charged from the outside or externally, remains free, that is to say, does not communicate with the iron melt 2.
- the receiving compartment or chamber 3 is charged with the vaporizable additive 5 with the addition of possible further additives, as will be explained hereinafter.
- the charging opening of the receiving chamber or compartment 3 is closed and by means of a suitable cover member 6, the charging opening of the vessel 1 is likewise closed.
- the cover 6 contains an opening of 10 to 50 mm. diameter which is aligned with an opening in the tea can-like pouring spout of the vessel 1 when the cover 6 is in its closed position to vent the vessel.
- the entire treatment vessel 1 can be tilted by a remote controlled drive mechanism (not shown) into the treatmen or vertically extending position depicted in FIG. 2.
- a remote controlled drive mechanism not shown
- the receiving compartment 3 is located below the surface of the melt 2, and the melt passes via the openings 7 and 8 into the interior of the receiving compart-ment 3 where it contacts the additive 5 causing vaporization of the same.
- the formed vapor escapes in accordance with the lift through the discharge openings 8 arranged at the top of the receiving compartment 3, while the melt 2 continuously flows through the inlet openings 7 arranged at the lower region of the receiving compartment 3.
- the delivery of the heat in this manner assists and supports the vaporization process which is associated with a considerable take-up of heat.
- the walls of the compartment 3 are preferably formed of refractory material, preferably clay graphite plates of 10 to 50 mm. thickness.
- the openings 7 are preferably of a diameter of 20 to 40 mm. and the openings 8 are preferably of a diameter of to 30 mm. with the openings 8 distributed over at least a third of the base surface of the vessel 1 and the entire cross-sectional area of the openings 7 being smaller than the entire cross-sectional area of the openings 8.
- the inlet openings 7 are subjected to a greater hydrostatic pressure (H than the outlet or discharge openings 8 I-I Due to contact of the molten cast iron with the magnesium, there result vapor bubbles which escape through the discharge openings 8. Consequently, there exists a through-flow of the molten cast iron through the receiving compartment 3, so that there occurs a uniform reaction of the magnesium.
- the vapor bubbles escaping through the openings 8 move through the melt 2 towards the top and, in so doing, are intentionally taken up in part by the melt.
- the melt which is treated in this manner is again emptied through the filling openings by tilting the treatment vessel 1.
- Example 1 A cast iron melt of the following chemical composi tion:
- the magnesium yield amounted to 66%.
- the structure of the cast test pieces after innoculation with 0.5% ferrosilicon consisted of spherical graphite, that is to say, 96% Type VI according to VDG Merkblatt, P 441 and 4% Type V.
- Example 2 A malleable cast iron melt of the following chemical composition:
- the above method is especially suitable for the carburization of cast iron, and indeed, specifically for the production of cast iron with spherical graphite.
- the carbon for carburization of the melt after filling of the starting melt, is added to the uncovered bath in the converter which is located in its horizontally extending position. After the subsequent rocking or pivoting of the converter into the vertically extending position, the vaporizing magnesium brings about a pronounced agitation of the bath which promotes carburization. Furthermore, the strongly reducing conditions, the basic slag, and the reduction of the sulfur content, act favorably for carburization. Due to the cooperation of these conditions, it is possible to desulfurize a melt in a single working operation within! approximately 70 seconds to approximately 0.003% final sulfur content, and the carbon content can be increased by approximately 0.6% and the residual magnesium content can be regulated to the amount necessary for cast iron with spherical graphite.
- the formation of slag in the receiving compartment and in the openings between this compartment and the treatment vessel can be prevented by the addition of small amounts of fluxing agents, such as NaCl.
- the fluxing agent is added to the pure magnesium ingots, for instance, in a ratio of 0.2 kg. NaCl/ 1000 kg. iron prior to treatment in the receiving compartment.
- said zone having at least one inflow orifice and at least one outflow orifice
- the total cross-sectional area of said at least one inflow orifice being smaller than the total crosssectional area of said at least one outflow orifice, said at least one inflow orifice and said at least one outflow orifice being spaced from each other by a significant distance;
- said additive being vaporizable at the temperature of the molten metal in said melt-confining zone and said quantity being adequate to effect an improving effect on said body of molten metal; and positioning said reaction zone, with said reaction zone sealed save for said at least one inflow orifice and said at least one outflow orifice, in a location at the bottom of said melt-confining zone, with said at least one inflow orifice adjacent the bottom of said meltconfining zone and said at least one outflow orifice spaced thereabove,
- reaction zone being located a substantial distance below the surface of said body of molten metal and there being a significant difference between the hydrostatic pressure applied by said body of molten metal at said at least one outflow orifice and the hydrostatic pressure applied by said body of molten metal at said at least one inflow orifice due to the space between said inflow and outflow orifice,
- said additive is selected from the group consisting of magnesium alloys.
- said step of positioning said reaction zone is carried out to locate the same adjacent one wall of said meltconfining zone, the transverse extent of said reaction zone being smaller than the transverse extent of said melt-confining zone.
- said additive is magnesium
- the method further comprises adding carbon to said molten metal for carburization thereof,
- said carbon being present in the melt when the molten metal enters said reaction zone, the vapors escaping from said reaction zone agitating the melt to promote carburization thereof.
- the total cross-sectional area of said at least one inflow orifice being smaller than the total crosssectional area of said at least one outflow orifice, the locations of said at least one inflow orifice and said at least one outflow orifice being spaced from each other by a significant distance; and confining a body of the molten metal to be treated in a space which surrounds said chamber in such fashion that said chamber is located at the bottom of the body of molten metal and said at least one outflow orifice is spaced above said at least one inflow orifice, said space being vented to the atmosphere at a point above the surface of the body of molten metal; said solid metallic additive vaporizing at the temperature of said molten metal and the quantity of said additive placed in said chamber being adequate to provide an improving effect on the quantity of said molten metal confined in said space; presence of said body of molten metal in said space, and the fact that said body provides a hydrostatic pressure at the location of said at least one inflow orifice which is greater than the
- said chamber is of smaller horizontal extent than is said space and is positioned off-center relative to said space, whereby a portion of said body of molten metal is beside said chamber, and
- said at least one outflow orifice is directed generally upwardly and said at least one inflow orifice is directed generally laterally to communicate between the interior of said chamber and said portion of said body of molten metal which is beside said chamber.
- said molten metal is a cast-iron melt having a substantial sulfur content; said additive is pure magnesium metal; and the method further comprises adding carbon to said molten metal for carburization thereof,
- said carbon being present in said body of molten metal when molten metal flows into said chamber via said at least one inflow orifice, the magnesium vapor escaping from said chamber agitating said molten metal to promote carburization thereof.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Spinning Or Twisting Of Yarns (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH127468A CH509413A (de) | 1968-01-26 | 1968-01-26 | Vorrichtung zur Herstellung von Gusseisen mit Kugelgraphit |
CH1796168 | 1968-12-03 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3666449A true US3666449A (en) | 1972-05-30 |
Family
ID=25687175
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US793065*A Expired - Lifetime US3666449A (en) | 1968-01-26 | 1969-01-22 | Method for the introduction of volatile additives into a melt |
US00208074A Expired - Lifetime US3724829A (en) | 1968-01-26 | 1971-12-15 | Apparatus for the introduction of volatile additives into a melt |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00208074A Expired - Lifetime US3724829A (en) | 1968-01-26 | 1971-12-15 | Apparatus for the introduction of volatile additives into a melt |
Country Status (7)
Country | Link |
---|---|
US (2) | US3666449A (da) |
JP (3) | JPS496969B1 (da) |
BE (1) | BE727380A (da) |
DE (1) | DE1815214C3 (da) |
FR (1) | FR2000779B1 (da) |
GB (1) | GB1231372A (da) |
SE (1) | SE391947B (da) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3747912A (en) * | 1971-04-23 | 1973-07-24 | Fischer Ag Georg | Converter for treatment of molten ductile cast iron with vaporizable additives |
US3778250A (en) * | 1969-02-26 | 1973-12-11 | Jones & Laughlin Steel Corp | Method for treating metallic melts |
US3819365A (en) * | 1969-03-13 | 1974-06-25 | Materials & Methods Ltd | Process for the treatment of molten metals |
DE2331783A1 (de) * | 1973-06-22 | 1975-01-23 | Kloeckner Humboldt Deutz Ag | Vorrichtung zum einbringen von reinmagnesium in eine gusseisenschmelze |
US3955974A (en) * | 1971-05-18 | 1976-05-11 | Georg Fischer Aktiengesellschaft | Apparatus and method for treating a metal melt with a vaporizable substance |
US4199353A (en) * | 1977-01-18 | 1980-04-22 | Canron Inc. | Molten metal treatment |
US4412674A (en) * | 1980-05-09 | 1983-11-01 | Mitsubishi Jukogyo Kabushiki Kaisha | High-temperature reduced iron production |
FR2578268A1 (fr) * | 1985-02-14 | 1986-09-05 | Fischer Ag Georg | Procede pour empecher la formation de depots dans des rigoles d'inducteurs, des descentes de coulee, des chenaux de coulee et analogues, utilisation de ce procede et dispositif pour sa mise en oeuvre. |
US4624702A (en) * | 1984-12-21 | 1986-11-25 | Georg Fischer Aktiengesellschaft | Method of vaporizing additives in metal melts |
GB2239029A (en) * | 1989-11-28 | 1991-06-19 | Fischer Ag Georg | Treating metallic melt with magnesium |
US5215709A (en) * | 1991-04-05 | 1993-06-01 | Tubi Ghisa S.P.A. | Method and device for treatment of metal baths by means of a material having a high gas vapor potential |
CN102084010A (zh) * | 2009-05-06 | 2011-06-01 | 福塞科国际有限公司 | 处理钢包 |
CN108788027A (zh) * | 2018-06-23 | 2018-11-13 | 共享装备股份有限公司 | 球墨铸铁的球化装置及球化方法 |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH564605A5 (da) * | 1971-10-05 | 1975-07-31 | Fischer Ag Georg | |
DE2208960C3 (de) * | 1972-02-25 | 1982-06-24 | Klöckner-Humboldt-Deutz AG, 5000 Köln | Tauchgefäß aus feuerfestem Material zum Einbringen von Reinmagnesium in eine Gußeisenschmelze |
JPS50125674U (da) * | 1974-04-01 | 1975-10-15 | ||
BR7402666A (pt) * | 1974-04-04 | 1975-12-09 | Foseco Do Brasil Produtos Para | Processo e equipamento para fabricacao de ferro fundido nodular |
JPS53123258U (da) * | 1977-03-09 | 1978-09-30 | ||
PL114811B1 (en) * | 1978-07-17 | 1981-02-28 | Przedsieb Projektowania Wyposa | Cast iron spheroidizing apparatus |
JPS5533185U (da) * | 1978-08-25 | 1980-03-03 | ||
DE3105200A1 (de) * | 1981-02-13 | 1983-01-20 | Metallgesellschaft Ag, 6000 Frankfurt | Kippbares gefaess zur behandlung von gusseisenschmelzen |
CH656147A5 (de) * | 1981-03-31 | 1986-06-13 | Fischer Ag Georg | Verfahren zur herstellung eines gusseisens mit vermiculargraphit. |
DE8224282U1 (de) * | 1982-06-07 | 1982-12-02 | Georg Fischer AG, 8201 Schaffhausen | Giesseinrichtung, insbesondere konverter zum vergiessen und/oder zum nachbehandeln von geschmolzenem material |
JPS6150872U (da) * | 1984-09-08 | 1986-04-05 | ||
AT388569B (de) * | 1984-12-21 | 1989-07-25 | Fischer Ag Georg | Verfahren zum verdampfen von zusatzstoffen in einer metallschmelze |
CH671033A5 (da) * | 1985-01-29 | 1989-07-31 | Fischer Ag Georg | |
CH668925A5 (de) * | 1985-12-31 | 1989-02-15 | Fischer Ag Georg | Behandlungsgefaess zur behandlung von fluessigen metall-legierungen. |
CH671955A5 (da) * | 1987-01-15 | 1989-10-13 | Fischer Ag Georg | |
CH680270A5 (da) * | 1990-01-05 | 1992-07-31 | Fischer Ag Georg | |
DE10207434A1 (de) * | 2002-02-21 | 2003-09-04 | Disa Ind Ag Schaffhausen | Konverter zur Magnesiumbehandlung von Gusseisenschmelzen |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2698749A (en) * | 1951-06-06 | 1955-01-04 | John M Fishell | Apparatus for introducing solid metal into molten metal |
LU34133A1 (da) * | 1955-01-24 |
-
1968
- 1968-12-17 DE DE1815214A patent/DE1815214C3/de not_active Expired
-
1969
- 1969-01-22 US US793065*A patent/US3666449A/en not_active Expired - Lifetime
- 1969-01-23 FR FR696901194A patent/FR2000779B1/fr not_active Expired
- 1969-01-24 GB GB1231372D patent/GB1231372A/en not_active Expired
- 1969-01-24 JP JP47096671A patent/JPS496969B1/ja active Pending
- 1969-01-24 BE BE727380D patent/BE727380A/xx not_active IP Right Cessation
- 1969-01-24 JP JP47096669A patent/JPS4911971B1/ja active Pending
- 1969-01-24 SE SE6900972A patent/SE391947B/xx unknown
-
1971
- 1971-12-15 US US00208074A patent/US3724829A/en not_active Expired - Lifetime
-
1972
- 1972-09-28 JP JP47096668A patent/JPS496968B1/ja active Pending
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3778250A (en) * | 1969-02-26 | 1973-12-11 | Jones & Laughlin Steel Corp | Method for treating metallic melts |
US3819365A (en) * | 1969-03-13 | 1974-06-25 | Materials & Methods Ltd | Process for the treatment of molten metals |
US3747912A (en) * | 1971-04-23 | 1973-07-24 | Fischer Ag Georg | Converter for treatment of molten ductile cast iron with vaporizable additives |
US3955974A (en) * | 1971-05-18 | 1976-05-11 | Georg Fischer Aktiengesellschaft | Apparatus and method for treating a metal melt with a vaporizable substance |
DE2331783A1 (de) * | 1973-06-22 | 1975-01-23 | Kloeckner Humboldt Deutz Ag | Vorrichtung zum einbringen von reinmagnesium in eine gusseisenschmelze |
US4199353A (en) * | 1977-01-18 | 1980-04-22 | Canron Inc. | Molten metal treatment |
US4296920A (en) * | 1977-01-18 | 1981-10-27 | Canron Inc. | Molten metal treatment |
US4412674A (en) * | 1980-05-09 | 1983-11-01 | Mitsubishi Jukogyo Kabushiki Kaisha | High-temperature reduced iron production |
US4624702A (en) * | 1984-12-21 | 1986-11-25 | Georg Fischer Aktiengesellschaft | Method of vaporizing additives in metal melts |
FR2578268A1 (fr) * | 1985-02-14 | 1986-09-05 | Fischer Ag Georg | Procede pour empecher la formation de depots dans des rigoles d'inducteurs, des descentes de coulee, des chenaux de coulee et analogues, utilisation de ce procede et dispositif pour sa mise en oeuvre. |
GB2239029A (en) * | 1989-11-28 | 1991-06-19 | Fischer Ag Georg | Treating metallic melt with magnesium |
US5098651A (en) * | 1989-11-28 | 1992-03-24 | Georg Fischer Ag | Magnesium treatment process and apparatus for carrying out this process |
AU637433B2 (en) * | 1989-11-28 | 1993-05-27 | Georg Fischer Aktiengesellschaft | Magnesium treatment process and apparatus for carrying out this process |
GB2239029B (en) * | 1989-11-28 | 1994-06-15 | Fischer Ag Georg | Magnesium treatment process and apparatus |
US5215709A (en) * | 1991-04-05 | 1993-06-01 | Tubi Ghisa S.P.A. | Method and device for treatment of metal baths by means of a material having a high gas vapor potential |
CN102084010A (zh) * | 2009-05-06 | 2011-06-01 | 福塞科国际有限公司 | 处理钢包 |
US20120152060A1 (en) * | 2009-05-06 | 2012-06-21 | Emmanuel Berthelet | Treatment ladle |
CN102084010B (zh) * | 2009-05-06 | 2014-08-27 | 福塞科国际有限公司 | 处理钢包 |
CN108788027A (zh) * | 2018-06-23 | 2018-11-13 | 共享装备股份有限公司 | 球墨铸铁的球化装置及球化方法 |
Also Published As
Publication number | Publication date |
---|---|
DE1815214C3 (de) | 1975-06-19 |
US3724829A (en) | 1973-04-03 |
FR2000779A1 (da) | 1969-09-12 |
DE1815214A1 (de) | 1969-12-11 |
GB1231372A (da) | 1971-05-12 |
JPS4911971B1 (da) | 1974-03-20 |
SE391947B (sv) | 1977-03-07 |
JPS496968B1 (da) | 1974-02-18 |
FR2000779B1 (da) | 1973-03-16 |
BE727380A (da) | 1969-07-01 |
DE1815214B2 (de) | 1974-11-07 |
JPS496969B1 (da) | 1974-02-18 |
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