CA1218846A - Method of minimizing slag carryover - Google Patents
Method of minimizing slag carryoverInfo
- Publication number
- CA1218846A CA1218846A CA000427405A CA427405A CA1218846A CA 1218846 A CA1218846 A CA 1218846A CA 000427405 A CA000427405 A CA 000427405A CA 427405 A CA427405 A CA 427405A CA 1218846 A CA1218846 A CA 1218846A
- Authority
- CA
- Canada
- Prior art keywords
- taphole
- furnace
- slag
- metal
- opening
- 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
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B3/00—General features in the manufacture of pig-iron
- C21B3/04—Recovery of by-products, e.g. slag
- C21B3/06—Treatment of liquid slag
-
- 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
- C21C5/4653—Tapholes; Opening or plugging thereof
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
- Furnace Charging Or Discharging (AREA)
- Manufacturing Of Electric Cables (AREA)
- Package Closures (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The invention relates to a method of minimizing slag carryover when draining molten metal from a furnace. A polyhedral-shaped body having density intermediate that of the slag and metal is thrown onto the surface of the slag within a restricted area over the furnace taphole. The body will float at the slag-metal interface, and tend to lodge with one of its corners projecting into the taphole as the final portion of remaining metal drains out of the furnace.
The shape of the body and its dimensions are selected so as to only partially block the taphole opening, causing flaring of the stream so as to signal a furnace operator of the impending flow of slag from the furnace. The operator then shuts off flow to prevent carryover of slag onto the molten metal already tapped, Since only the edges of the body contact the taphole, of the body does not become welded to the wall of the taphole and therefore is easily dislodged without loss of time between heats.
The invention relates to a method of minimizing slag carryover when draining molten metal from a furnace. A polyhedral-shaped body having density intermediate that of the slag and metal is thrown onto the surface of the slag within a restricted area over the furnace taphole. The body will float at the slag-metal interface, and tend to lodge with one of its corners projecting into the taphole as the final portion of remaining metal drains out of the furnace.
The shape of the body and its dimensions are selected so as to only partially block the taphole opening, causing flaring of the stream so as to signal a furnace operator of the impending flow of slag from the furnace. The operator then shuts off flow to prevent carryover of slag onto the molten metal already tapped, Since only the edges of the body contact the taphole, of the body does not become welded to the wall of the taphole and therefore is easily dislodged without loss of time between heats.
Description
~LZ18846 METHOD OF MINIMIZING SLAG CARRYOVER
This invention relates to a method of minimizing slag carryover during tapping of molten metal from a furnace.
It is desirable in order to improve ladle addition recoveries and deoxidation control in steel making to minimize carryover of slag with the molten metal as it is tapped from the furnace.
juries stopper devices have been used for plug-in the toughly of BOY and Q-BOP furnaces to prevent drainage of slag at the beginning of the tap when the furnace is first tilted downward to drain the metal out. However, most of the slag gets into the ladle as a result of becoming entrained with the metal in a vortex which forms at the toughly en-trance as the final portion of metal is drained from the furnace.
Two different approaches have been made toward solving this latter problem. In one, a device located on the exterior of the furnace is actuated to physically cut off the stream as slag begins to flow out of the toughly. A second approach has been to insert into the furnace a ~Z~8846 floatable stopper which floats at the slag-metal interface and becomes lodged in the toughly.
However, these floatable stoppers have the disadvantage what they tend to weld to the wall of the toughly and are difficult to dislodge, requiring burning with an oxygen lance. This also increases wear in the toughly itself. Examples of prior floatable stoppers are shown in Stahl Undo Risen, Volume 90, pages 257-263 and Japanese Patent Application 47-20803 published April 4, 1979.
According to the present invention, there is provided a method of minimizing slag carryover upon draining molten metal from a furnace through a toughly, comprising dropping onto the surface of molten slag and metal in said furnace, within an area above said toughly, a body having a density intermediate that of the molten metal and slag in said furnace and having a cross-section of minimum dimension greater than the maximum dimension of the cross-section of the opening of said toughly, draining molten metal from the furnace through the toughly opening, and then shutting off flow through said toughly so as to prevent carryover of slag onto the molten metal already tapped from the furnace, characterized in that said body has equilateral generally planar faces, the intersections of which lX18846 are adapted to lodge in the toughly so that said body blocks 20 to 80 percent of the toughly opening when said body becomes lodged in said toughly opening, and the method includes monitoring the condition of the stream emerging from said toughly so as to obtain an indication of flaring of said stream when said body lodges in the toughly.
For use in steel making a body having a density of .12 to .22 pounds per cubic inch (3320 to 6090 kg/m3) is preferred. The body is of a material substantially indissoluble in the molten metal and slag.
The body preferably has a maximum dimension in any direction of five to twelve inches (13 to 30cm) and is adapted to block 20 and 80 percent of a round toughly opening having a diameter of four to ten inches (10 to 25cm.) when an intersection of the faces of the body is lodged centrally therein.
Thus, when the final portion of metal starts to flow out of the furnace, the body will tend to lodge in the toughly, causing the stream to flare since the hole is only partially blocked. The flaring stream acts as a signal to a furnace operator that slag will start to flow soon. Thus, the operator may shut off flow, preventing slag carryover onto the metal in the ladle. A primary advantage of the foe polyhedral-shaped device is that it does not become permanently lodged in the toughly and does not require burning with an oxygen lance in order to remove it from the toughly.
The body may have faces all of the same shape and size. A cubed shape is preferred. the body may be of refractory material having solid metal particles distributed therein to increase its density. The metal particles may be shot or fibers or both, the latter serving to increase cohesiveness of the body. Preferably, carbon steel shot is used whereas the fibers are of stainless steel composition The invention is further described, by way of example, with reference to the accompanying drawings, in which:-Figure 1 is a cross-section of a furnace tilted into tapping position for draining molten metal through a toughly of the furnace and showing the location of a floating stopper, and Figure 2 is a schematic illustration of how the floating stopper lodges in the toughly.
Referring to Figure 1, a steel making converter 10 is shown having a refractory lining 12 and a toughly 14 located near the mouth 16 of the converter vessel. The vessel is shown tilted 1~1884~;
downwardly from its normal upright position, 60 that molten metal 18 and slag 20 will drain therefrom.
A cube 22 is floating at the slag-metal interface during the tap. Referring to Figure 2, the cube 22 is shown lodged in the toughly 24 only partially blocking the toughly opening. For a six-inch tlScm-) diameter toughly, a cube 7 or 8 itches (18 or 20cm.) on each face has been found to work satisfactorily. A seven-inch (18 cm.) cube is preferred. It will block about 40 percent of the cross-section of a six-inch (15 cm.) diameter toughly.
The cube may be of any refractory material resistant to dissolution in the metal and slag, at least sufficiently to maintain the minimum dimensions necessary for lodging in the toughly.
Cartable refractory is preferred. Seven-inch (18 cm.) cubes having a density of from Owls to 0.17 lbs/in.3, (4150 to 4710 kg/m3) have been used although any density between that of the slag and metal should suffice. or example, molten steel has a density of about 0.25 lbs/in.3(6920 kg/m3), whereas steel making slags have density of about 0.10 lbs/in.3 (2770 kg/m3). Shown below are examples of mixtures used for making typical cubes:
ISSUE
TABLE I
CUBE A 7 inches (18 cm.) on each side with density of 0.15 lbs/in.3(4150 kg/m3) Weight lobs. kg.
Refractory Cement 3.4 Fine Ironware Concentrate 15.2 6.9 Steel Shot 28.6 13.0 Water 2.5 1.1 Stainless Steel Fibers 1.5 0.7 CUBE B 7 inches (18cm.) on each side with density of 0.17 lbs/in.3 (4710 kg/m3) Weight lobs. kg.
Refractory Cement 2.4 Fine Iron-Ore Concentrate 10.4 4.7 Steel Shot 42.7 19.4 Water 2.5 1.1 Stainless Steel Fibers 1.5 0.7 The steel shot is of a type readily avail-fable and is used for increasing the density of the cube. Iron ore is used since it reacts with carbon in the steel bath and indicates where the submerged cube is located. The stainless steel fibers tend to bind the refractory preventing the cube from breaking apart prematurely. Of course, it is desirable to completely dry the cubes in order to remove moisture which reacts with the metal, causing the cubes to crack and break.
It is important that the cube be dropped into a restricted area over the toughly so as to assure its being carried by fluid currents in the metal during tap into an area directly over the toughly so that it will lodge therein. It has been found that the angle of downward tilt of BOY or Q-BOP furnace at the end of tap, if tilted so as to obtain the maximum rate of draining metal, varies from about I to 103 from vertical. The range of angles is due to various factors such as erosion of the furnace lining and solid slag or metal buildup at the furnace mouth. It has been found that reasonable estimates of the location of the toughly can be made by calculating the horizontal distance of the toughly from the furnace trunnions for various angles of tilt of the furnace. The location of the toughly from the trunnions at the end of tap will vary over about four feet (1.2m). Thus it has been found best to insert the cube in the middle of the calculated four-foot (1.2m) distance. This can be accomplished by various means from floor level at a location adjacent the furnace mouth.
121884~
The cube should also be inserted into the furnace just before a vortex forms as the final portion of metal starts to drain out. This time may be calculated from the estimated tonnage of metal contained in the furnace, the size and shape of the toughly in relation to metal bath so as to arrive at a critical tonnage of metal left in the furnace when vortexing will begin to occur. This critical tonnage may be calculated for conventional steel making BOY or Q-BOP vessels from a formula.
Normally, it is preferred to add the cube within a calculated time of one to two minutes before all of the metal has drained from the furnace.
This invention relates to a method of minimizing slag carryover during tapping of molten metal from a furnace.
It is desirable in order to improve ladle addition recoveries and deoxidation control in steel making to minimize carryover of slag with the molten metal as it is tapped from the furnace.
juries stopper devices have been used for plug-in the toughly of BOY and Q-BOP furnaces to prevent drainage of slag at the beginning of the tap when the furnace is first tilted downward to drain the metal out. However, most of the slag gets into the ladle as a result of becoming entrained with the metal in a vortex which forms at the toughly en-trance as the final portion of metal is drained from the furnace.
Two different approaches have been made toward solving this latter problem. In one, a device located on the exterior of the furnace is actuated to physically cut off the stream as slag begins to flow out of the toughly. A second approach has been to insert into the furnace a ~Z~8846 floatable stopper which floats at the slag-metal interface and becomes lodged in the toughly.
However, these floatable stoppers have the disadvantage what they tend to weld to the wall of the toughly and are difficult to dislodge, requiring burning with an oxygen lance. This also increases wear in the toughly itself. Examples of prior floatable stoppers are shown in Stahl Undo Risen, Volume 90, pages 257-263 and Japanese Patent Application 47-20803 published April 4, 1979.
According to the present invention, there is provided a method of minimizing slag carryover upon draining molten metal from a furnace through a toughly, comprising dropping onto the surface of molten slag and metal in said furnace, within an area above said toughly, a body having a density intermediate that of the molten metal and slag in said furnace and having a cross-section of minimum dimension greater than the maximum dimension of the cross-section of the opening of said toughly, draining molten metal from the furnace through the toughly opening, and then shutting off flow through said toughly so as to prevent carryover of slag onto the molten metal already tapped from the furnace, characterized in that said body has equilateral generally planar faces, the intersections of which lX18846 are adapted to lodge in the toughly so that said body blocks 20 to 80 percent of the toughly opening when said body becomes lodged in said toughly opening, and the method includes monitoring the condition of the stream emerging from said toughly so as to obtain an indication of flaring of said stream when said body lodges in the toughly.
For use in steel making a body having a density of .12 to .22 pounds per cubic inch (3320 to 6090 kg/m3) is preferred. The body is of a material substantially indissoluble in the molten metal and slag.
The body preferably has a maximum dimension in any direction of five to twelve inches (13 to 30cm) and is adapted to block 20 and 80 percent of a round toughly opening having a diameter of four to ten inches (10 to 25cm.) when an intersection of the faces of the body is lodged centrally therein.
Thus, when the final portion of metal starts to flow out of the furnace, the body will tend to lodge in the toughly, causing the stream to flare since the hole is only partially blocked. The flaring stream acts as a signal to a furnace operator that slag will start to flow soon. Thus, the operator may shut off flow, preventing slag carryover onto the metal in the ladle. A primary advantage of the foe polyhedral-shaped device is that it does not become permanently lodged in the toughly and does not require burning with an oxygen lance in order to remove it from the toughly.
The body may have faces all of the same shape and size. A cubed shape is preferred. the body may be of refractory material having solid metal particles distributed therein to increase its density. The metal particles may be shot or fibers or both, the latter serving to increase cohesiveness of the body. Preferably, carbon steel shot is used whereas the fibers are of stainless steel composition The invention is further described, by way of example, with reference to the accompanying drawings, in which:-Figure 1 is a cross-section of a furnace tilted into tapping position for draining molten metal through a toughly of the furnace and showing the location of a floating stopper, and Figure 2 is a schematic illustration of how the floating stopper lodges in the toughly.
Referring to Figure 1, a steel making converter 10 is shown having a refractory lining 12 and a toughly 14 located near the mouth 16 of the converter vessel. The vessel is shown tilted 1~1884~;
downwardly from its normal upright position, 60 that molten metal 18 and slag 20 will drain therefrom.
A cube 22 is floating at the slag-metal interface during the tap. Referring to Figure 2, the cube 22 is shown lodged in the toughly 24 only partially blocking the toughly opening. For a six-inch tlScm-) diameter toughly, a cube 7 or 8 itches (18 or 20cm.) on each face has been found to work satisfactorily. A seven-inch (18 cm.) cube is preferred. It will block about 40 percent of the cross-section of a six-inch (15 cm.) diameter toughly.
The cube may be of any refractory material resistant to dissolution in the metal and slag, at least sufficiently to maintain the minimum dimensions necessary for lodging in the toughly.
Cartable refractory is preferred. Seven-inch (18 cm.) cubes having a density of from Owls to 0.17 lbs/in.3, (4150 to 4710 kg/m3) have been used although any density between that of the slag and metal should suffice. or example, molten steel has a density of about 0.25 lbs/in.3(6920 kg/m3), whereas steel making slags have density of about 0.10 lbs/in.3 (2770 kg/m3). Shown below are examples of mixtures used for making typical cubes:
ISSUE
TABLE I
CUBE A 7 inches (18 cm.) on each side with density of 0.15 lbs/in.3(4150 kg/m3) Weight lobs. kg.
Refractory Cement 3.4 Fine Ironware Concentrate 15.2 6.9 Steel Shot 28.6 13.0 Water 2.5 1.1 Stainless Steel Fibers 1.5 0.7 CUBE B 7 inches (18cm.) on each side with density of 0.17 lbs/in.3 (4710 kg/m3) Weight lobs. kg.
Refractory Cement 2.4 Fine Iron-Ore Concentrate 10.4 4.7 Steel Shot 42.7 19.4 Water 2.5 1.1 Stainless Steel Fibers 1.5 0.7 The steel shot is of a type readily avail-fable and is used for increasing the density of the cube. Iron ore is used since it reacts with carbon in the steel bath and indicates where the submerged cube is located. The stainless steel fibers tend to bind the refractory preventing the cube from breaking apart prematurely. Of course, it is desirable to completely dry the cubes in order to remove moisture which reacts with the metal, causing the cubes to crack and break.
It is important that the cube be dropped into a restricted area over the toughly so as to assure its being carried by fluid currents in the metal during tap into an area directly over the toughly so that it will lodge therein. It has been found that the angle of downward tilt of BOY or Q-BOP furnace at the end of tap, if tilted so as to obtain the maximum rate of draining metal, varies from about I to 103 from vertical. The range of angles is due to various factors such as erosion of the furnace lining and solid slag or metal buildup at the furnace mouth. It has been found that reasonable estimates of the location of the toughly can be made by calculating the horizontal distance of the toughly from the furnace trunnions for various angles of tilt of the furnace. The location of the toughly from the trunnions at the end of tap will vary over about four feet (1.2m). Thus it has been found best to insert the cube in the middle of the calculated four-foot (1.2m) distance. This can be accomplished by various means from floor level at a location adjacent the furnace mouth.
121884~
The cube should also be inserted into the furnace just before a vortex forms as the final portion of metal starts to drain out. This time may be calculated from the estimated tonnage of metal contained in the furnace, the size and shape of the toughly in relation to metal bath so as to arrive at a critical tonnage of metal left in the furnace when vortexing will begin to occur. This critical tonnage may be calculated for conventional steel making BOY or Q-BOP vessels from a formula.
Normally, it is preferred to add the cube within a calculated time of one to two minutes before all of the metal has drained from the furnace.
Claims (6)
1. A method for minimizing slag carryover upon draining molten metal from a furnace through a taphole therein, said method comprising:
dropping a polyhedral-shaped body onto the surface of molten slag and metal in said furnace within a restricted area above said taphole so as to insure that said body will be drawn into the taphole as a final portion of metal drains out of the furnace, said body having a cross-section of minimum dimension greater than the maximum dimension of the cross-section of the opening of said taphole, said body having a density intermediate that of the molten metal and slag in said furnace, said body being substantially resistant to dissolution in the molten metal and slag so as to retain minimum cross-sectional dimensions greater than the taphole opening for a time sufficient to assure the body will lodge in the taphole opening, said body having equilateral generally planar faces, the intersections of which are adapted to lodge in the taphole without completely blocking the taphole opening, said body having dimensions for blocking between 20 to 80 percent of the taphole opening when an intersection thereof becomes lodged centrally in said taphole opening, draining molten metal from the furnace through the taphole opening, monitoring the condition of the stream emanating from said taphole so as to obtain an indication of flaring of said stream when said body lodges therein, and then shutting off flow through said taphole so as to prevent carryover of slag onto the molten metal already tapped from the furnace.
dropping a polyhedral-shaped body onto the surface of molten slag and metal in said furnace within a restricted area above said taphole so as to insure that said body will be drawn into the taphole as a final portion of metal drains out of the furnace, said body having a cross-section of minimum dimension greater than the maximum dimension of the cross-section of the opening of said taphole, said body having a density intermediate that of the molten metal and slag in said furnace, said body being substantially resistant to dissolution in the molten metal and slag so as to retain minimum cross-sectional dimensions greater than the taphole opening for a time sufficient to assure the body will lodge in the taphole opening, said body having equilateral generally planar faces, the intersections of which are adapted to lodge in the taphole without completely blocking the taphole opening, said body having dimensions for blocking between 20 to 80 percent of the taphole opening when an intersection thereof becomes lodged centrally in said taphole opening, draining molten metal from the furnace through the taphole opening, monitoring the condition of the stream emanating from said taphole so as to obtain an indication of flaring of said stream when said body lodges therein, and then shutting off flow through said taphole so as to prevent carryover of slag onto the molten metal already tapped from the furnace.
2. The method of claim 1 wherein said step of inserting the body into the furnace includes inserting the body onto the surface of said slag within a four-foot (4') diameter circle centrally located with respect to the range of taphole locations upon tilting of the furnace for maximum drain on successive heats throughout a full furnace campaign.
3. The method of claim 1 wherein said step of inserting the body is carried out at a calculated time within the range of one to two minutes before the end of tap when all metal has been drained from the furnace.
4. The method of claim 1 wherein said body is of cubed shape.
5. The method of claim 1 wherein said body comprises cast refractory material having solid metal particles distributed therein, said metal particles including steel shot distributed therein.
6. The method of claim 8 wherein said body further includes iron ore particles.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US37680082A | 1982-05-10 | 1982-05-10 | |
| US376,800 | 1982-05-10 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1218846A true CA1218846A (en) | 1987-03-10 |
Family
ID=23486561
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000427405A Expired CA1218846A (en) | 1982-05-10 | 1983-05-04 | Method of minimizing slag carryover |
Country Status (15)
| Country | Link |
|---|---|
| EP (1) | EP0094241B1 (en) |
| JP (1) | JPS5952189A (en) |
| KR (1) | KR840004786A (en) |
| AR (1) | AR231706A1 (en) |
| AT (1) | ATE16945T1 (en) |
| AU (1) | AU552735B2 (en) |
| BR (1) | BR8302426A (en) |
| CA (1) | CA1218846A (en) |
| DE (1) | DE3361476D1 (en) |
| ES (1) | ES522241A0 (en) |
| FI (1) | FI73739C (en) |
| HU (1) | HU187077B (en) |
| IN (1) | IN159857B (en) |
| NO (1) | NO831649L (en) |
| YU (1) | YU102483A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2188132B (en) * | 1986-03-19 | 1990-06-13 | Labate Michael D | Slag retaining device for use in vessels such as converters, ladles or the like. |
| GB8712255D0 (en) * | 1987-05-23 | 1987-07-01 | Goricon Metallurg Services | Plug members |
| NL8801231A (en) * | 1988-05-11 | 1989-12-01 | Hoogovens Groep Bv | STOP FOR A STEEL CONVERTER. |
| CN104117668B (en) * | 2014-08-01 | 2016-03-02 | 莱芜钢铁集团有限公司 | A kind of large bag cast pushing off the slag floating plug and preparation and slag stopping method |
| DE102017114859A1 (en) * | 2017-07-04 | 2019-01-10 | Sms Group Gmbh | Apparatus for selectively controlling the tapping operation of a melt from an electric arc furnace |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2718389A (en) * | 1950-11-17 | 1955-09-20 | Electro Chimie Metal | Skimmer for holding slag back during pouring metal |
| AT259602B (en) * | 1965-07-05 | 1968-01-25 | Voest Ag | Process for improving the separation of metal and slag when pouring molten metal from a furnace vessel provided with a tap hole |
| DE1508223B1 (en) * | 1966-09-26 | 1970-04-09 | Mannesmann Ag | Float lock to hold back the slag during tapping with tapping converters |
| JPS4720803B1 (en) * | 1968-10-31 | 1972-06-13 |
-
1983
- 1983-05-04 CA CA000427405A patent/CA1218846A/en not_active Expired
- 1983-05-09 YU YU01024/83A patent/YU102483A/en unknown
- 1983-05-09 KR KR1019830001972A patent/KR840004786A/en not_active Application Discontinuation
- 1983-05-10 DE DE8383302619T patent/DE3361476D1/en not_active Expired
- 1983-05-10 JP JP58080259A patent/JPS5952189A/en active Pending
- 1983-05-10 ES ES522241A patent/ES522241A0/en active Granted
- 1983-05-10 NO NO831649A patent/NO831649L/en unknown
- 1983-05-10 AU AU14435/83A patent/AU552735B2/en not_active Ceased
- 1983-05-10 EP EP83302619A patent/EP0094241B1/en not_active Expired
- 1983-05-10 BR BR8302426A patent/BR8302426A/en unknown
- 1983-05-10 HU HU831619A patent/HU187077B/en unknown
- 1983-05-10 IN IN302/DEL/83A patent/IN159857B/en unknown
- 1983-05-10 AR AR292974A patent/AR231706A1/en active
- 1983-05-10 AT AT83302619T patent/ATE16945T1/en not_active IP Right Cessation
- 1983-05-10 FI FI831624A patent/FI73739C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| IN159857B (en) | 1987-06-13 |
| HU187077B (en) | 1985-11-28 |
| AU552735B2 (en) | 1986-06-19 |
| EP0094241B1 (en) | 1985-12-11 |
| NO831649L (en) | 1983-11-11 |
| ES8404415A1 (en) | 1984-04-16 |
| EP0094241A1 (en) | 1983-11-16 |
| FI73739B (en) | 1987-07-31 |
| JPS5952189A (en) | 1984-03-26 |
| YU102483A (en) | 1986-04-30 |
| ES522241A0 (en) | 1984-04-16 |
| FI831624A0 (en) | 1983-05-10 |
| ATE16945T1 (en) | 1985-12-15 |
| AU1443583A (en) | 1983-11-17 |
| BR8302426A (en) | 1984-01-10 |
| DE3361476D1 (en) | 1986-01-23 |
| FI831624L (en) | 1983-11-11 |
| AR231706A1 (en) | 1985-02-28 |
| FI73739C (en) | 1987-11-09 |
| KR840004786A (en) | 1984-10-24 |
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