EP0321478A1 - Casting powder for use in bottom pour ingot steel production and method for employing same. - Google Patents
Casting powder for use in bottom pour ingot steel production and method for employing same.Info
- Publication number
- EP0321478A1 EP0321478A1 EP87905525A EP87905525A EP0321478A1 EP 0321478 A1 EP0321478 A1 EP 0321478A1 EP 87905525 A EP87905525 A EP 87905525A EP 87905525 A EP87905525 A EP 87905525A EP 0321478 A1 EP0321478 A1 EP 0321478A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- mold
- casting powder
- steel
- expandable graphite
- molten steel
- 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.)
- Granted
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 52
- 239000010959 steel Substances 0.000 title claims abstract description 52
- 239000000843 powder Substances 0.000 title claims abstract description 30
- 238000005266 casting Methods 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 230000004907 flux Effects 0.000 claims abstract description 28
- 150000001875 compounds Chemical class 0.000 claims abstract description 27
- 239000000203 mixture Substances 0.000 claims abstract description 16
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 25
- 229910002804 graphite Inorganic materials 0.000 claims description 20
- 239000010439 graphite Substances 0.000 claims description 20
- 239000000126 substance Substances 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims 2
- 230000008569 process Effects 0.000 abstract description 7
- 239000012535 impurity Substances 0.000 abstract description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 238000007711 solidification Methods 0.000 description 5
- 230000008023 solidification Effects 0.000 description 5
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 3
- 239000000470 constituent Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 238000010405 reoxidation reaction Methods 0.000 description 3
- 239000002893 slag Substances 0.000 description 3
- 238000005336 cracking Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910052700 potassium Inorganic materials 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- PIGFYZPCRLYGLF-UHFFFAOYSA-N Aluminum nitride Chemical compound [Al]#N PIGFYZPCRLYGLF-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 241000208202 Linaceae Species 0.000 description 1
- 235000004431 Linum usitatissimum Nutrition 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- FZFYOUJTOSBFPQ-UHFFFAOYSA-M dipotassium;hydroxide Chemical compound [OH-].[K+].[K+] FZFYOUJTOSBFPQ-UHFFFAOYSA-M 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001473 noxious effect Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 229910001948 sodium oxide Inorganic materials 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
- B22D27/04—Influencing the temperature of the metal, e.g. by heating or cooling the mould
- B22D27/06—Heating the top discard of ingots
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D7/00—Casting ingots, e.g. from ferrous metals
- B22D7/12—Appurtenances, e.g. for sintering, for preventing splashing
Definitions
- This invention relates to mold powders employed in ingot steel production. More specifically, the present invention discloses a casting powder to be employed in bottom pour steel molds which has the unique ability to act as both a bottom pour flux and a hot topping compound.
- a sealed bag of bottom pour flux is suspended in the mold approximately six to eighteen inches above the inlet for the molten steel.
- the bottom pour flux consists of chemical compounds which melt and spread rapidly across the surface of the molten steel.
- the molten slag coating the surface of the steel acts to create the correct menisus shape and prevents oxidation of steel surface.
- the molten slag insulates the surface of the molten steel to slow solidification, and spreads a thin coat of homogenous glass between the mold and the molten steel to allow constant heat transfer and solidification and thus lessen thermally induced stresses and resultant cracking.
- the flux absorbs impurities such as deoxidation and reoxidation products and refractory particles.
- the bag containing the bottom pour flax burns upon the introduction of the molten steel into the mold thus automatically releasing the flux.
- hot topping compounds are not without its detractions. Adding hot topping compound is cumbersome, labor intensive, environmentally disruptive, and may contaminate the ingot steel.
- the present invention is directed to casting powders for use in ingot steel production through bottom pour process. Instead of the bottom pour flux and the hot topping compound presently employed, the present invention substitutes a single casting powder which provides the benefits of both the prior products.
- the present invention entails introducing a compound know as "expandable graphite" in place of a portion of the carbon component of a standard bottom pour flux.
- the resulting mixtur provides all the insulative and protective benefits of standard bottom pour fluxes as well as the full insulative requirements of hot topping compounds.
- the present invention is cleanly and automatically dispersed upon introduction of molten steel into the steel ingo molds. It eliminates the noxious by-products of hot topping compound and its potentially contaminating effect of "core of debris,” and does not require the labor input demanded for application of hot topping compound.
- the present invention provides a mixture of chemical components which function as a unique casting powder for bottom pour ingot steel production.
- the present invention combines the crucial properties of both bottom pour fluxes and hot topping compounds into a single, easily dispensed, composition.
- Bottom pour fluxes (or powders) presently employed are required to have specific qualities for covering and protecting molten steel rising in an ingot mold. These include: molten slag layer to completely coat the molten steel, to insulate, maintain a proper surface shape, protect against oxidation, and absorb deoxidation and reoxidation products; and an ability to form a thin layer of homogenous glass between the molten steel and the side walls of the mold so as to insulate, reduce thermally induced stresses and thus decrease cracking.
- composition of a traditional bottom pour flux may comprise the following:
- Hot topping compounds have only one primary purpose: to provide a thick insulative blanket on top of the molten steel to reduce the heat loss from the top to avoid "pipe.”
- Pipe is a condition which occurs when there is no molten steel to feed the shrinkage cavity formed due to ingot solidification. Due to the expansion of the steel while molten, this discrepancy leaves the sides too high in respect to the core. Thus, without proper insulation, the center of the steel ingot will solidify in a sunken position or with severe imperfections — creating an entire segment of the ingot which must be excised and discarded. To accomplish the necessary insulation, a wide variety of compositions have been utilized. Typical ranges are as follows: Constituent Percentage ( % ) Range by wen-m
- Expandable graphite is produced through treatment of high grade natural crystalline graphite through oxidation or electrolysis by various oxidizing materials. It is commercially available in a number of grades from graphite suppliers.
- expandable graphite When expandable graphite is heated rapidly it expands along the C-axis of the crystal to a magnitude of 40 to 300 times its original size.
- Iron Oxide (Fe2 ⁇ 3. 4.0 - 6.0
- the present invention is prepared in the same manner as standard bottom pour flux.
- Expandable graphite has different expansion rates according to its quality. It is desired to use expandable graphite that expands between 100 and 300 times its volume within the percentage weight range provided above. It is believed that ideally an expansion of 200 to 250 times its volume at a percentage weight of 6.0 to 8.0% should be employed.
- the casting powder has a viscosity nearly identical to that of standard bottom pour flux (i.e. at 1500°C, bottom pour flux has a viscosity of approximately 50-200 poise, the present invention produces a flux with a viscosity of 50-200 poise). Moreover, under pressure the present invention produces a unique quality compressio product having anistrophy. This results in a substance perfectly suitable to properly coat between the molten steel and the side walls of the ingot mold during pouring. Thus, the casting powder produced provides superior results as both a bottom pour flux and a hot topping compound.
- the casting powder is dispersed in the same manner as standard bottom pour flux. It is placed in a combustible container or bag, such as paper bag with grommet reinforcements, and suspended six to eighteen inches above the bottom of the ingot mold. It can also be preformed into a board and placed at the bottom of the mold. The incoming molten steel consumes the container or dissolves the board causing the release of the powder. The powder then rapidly spreads across the surface of the incoming molten steel. This is a clean, automatic process which requires little human input and supervision.
- the benefits of the present invention are realized through the elimination of hot topping compound. Personnel are no longer required to be stationed above the molds to apply the insulative material. Atmospheric dust from the hot topping compound and "core of debris" are also eliminated. Additionally, no smoke products are produced whatsoever. Despite the somewhat higher cost of substituting expandable graphite for standard graphite, the elimination of hot topping compound and the considerable cost savings in application provide a considerable overall cost savings.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Mold Materials And Core Materials (AREA)
Abstract
La poudre combine les propriétés fondamentales des fondants de coulée en source et des composés de coulée directe à chaud existants en un mélange unique que l'on peut distribuer aisément. L'invention ci-décrite simplifie de manière significative les procédés utilisés jusqu'à présent et permet de réaliser des économies tout en produisant un acier présentant moins d'impuretés.The powder combines the fundamental properties of source casting fluxes and existing direct hot casting compounds into a unique blend that can be easily dispensed. The invention described here significantly simplifies the processes used until now and allows savings to be made while producing a steel having less impurities.
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT87905525T ATE96708T1 (en) | 1986-08-13 | 1987-08-10 | CASTING POWDER IN BLOCK STEEL PRODUCTION IN THE BOTTOM CASTING AND METHOD FOR ITS USE. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US89606786A | 1986-08-13 | 1986-08-13 | |
US896067 | 1986-08-13 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0321478A1 true EP0321478A1 (en) | 1989-06-28 |
EP0321478A4 EP0321478A4 (en) | 1990-04-10 |
EP0321478B1 EP0321478B1 (en) | 1993-11-03 |
Family
ID=25405572
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP87905525A Expired - Lifetime EP0321478B1 (en) | 1986-08-13 | 1987-08-10 | Casting powder for use in bottom pour ingot steel production and method for employing same |
Country Status (9)
Country | Link |
---|---|
EP (1) | EP0321478B1 (en) |
JP (1) | JPH01501536A (en) |
KR (1) | KR880701599A (en) |
AU (1) | AU604503B2 (en) |
BR (1) | BR8707766A (en) |
CA (1) | CA1285461C (en) |
DE (1) | DE3788067T2 (en) |
MX (1) | MX169019B (en) |
WO (1) | WO1988001210A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ATE258090T1 (en) * | 1997-04-30 | 2004-02-15 | Stopinc Ag | SLIDING CLOSURE FOR A VESSEL CONTAINING MOLTEN METAL |
JP5366896B2 (en) * | 2010-07-07 | 2013-12-11 | 株式会社神戸製鋼所 | Bottom pouring method |
JP5807910B2 (en) * | 2011-11-15 | 2015-11-10 | 山陽特殊製鋼株式会社 | Coating agent for ingot casting |
JP6609139B2 (en) * | 2015-08-24 | 2019-11-20 | 山陽特殊製鋼株式会社 | Coating agent for the pouring ingot method |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3811898A (en) * | 1969-11-12 | 1974-05-21 | Fiseco Int Ltd | Heat-insulating antipiping compositions |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3308514A (en) * | 1965-01-07 | 1967-03-14 | Dow Chemical Co | Method of hot topping using vermicular graphite |
GB1431787A (en) * | 1973-03-28 | 1976-04-14 | Foseco Int | Casting of molten metals |
JPS5253727A (en) * | 1975-10-28 | 1977-04-30 | Fuoseko Japan Rimitetsudo Yuug | Formed additive for mold |
JPS6038201B2 (en) * | 1978-09-04 | 1985-08-30 | 石川島播磨重工業株式会社 | Rolled material edge shape control device |
-
1987
- 1987-08-10 EP EP87905525A patent/EP0321478B1/en not_active Expired - Lifetime
- 1987-08-10 JP JP62505033A patent/JPH01501536A/en active Pending
- 1987-08-10 AU AU78567/87A patent/AU604503B2/en not_active Ceased
- 1987-08-10 DE DE3788067T patent/DE3788067T2/en not_active Expired - Fee Related
- 1987-08-10 WO PCT/US1987/001958 patent/WO1988001210A1/en active IP Right Grant
- 1987-08-10 BR BR8707766A patent/BR8707766A/en not_active Application Discontinuation
- 1987-08-12 CA CA000544344A patent/CA1285461C/en not_active Expired - Fee Related
- 1987-08-18 MX MX007790A patent/MX169019B/en unknown
-
1988
- 1988-04-13 KR KR1019880700405A patent/KR880701599A/en not_active Application Discontinuation
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3811898A (en) * | 1969-11-12 | 1974-05-21 | Fiseco Int Ltd | Heat-insulating antipiping compositions |
Non-Patent Citations (1)
Title |
---|
See also references of WO8801210A1 * |
Also Published As
Publication number | Publication date |
---|---|
DE3788067T2 (en) | 1994-05-19 |
DE3788067D1 (en) | 1993-12-09 |
MX169019B (en) | 1993-06-17 |
AU7856787A (en) | 1988-03-08 |
CA1285461C (en) | 1991-07-02 |
BR8707766A (en) | 1989-08-15 |
EP0321478A4 (en) | 1990-04-10 |
EP0321478B1 (en) | 1993-11-03 |
KR880701599A (en) | 1988-11-04 |
JPH01501536A (en) | 1989-06-01 |
AU604503B2 (en) | 1990-12-20 |
WO1988001210A1 (en) | 1988-02-25 |
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