CN110747317B - Ladle type vacuum refining furnace - Google Patents
Ladle type vacuum refining furnace Download PDFInfo
- Publication number
- CN110747317B CN110747317B CN201911110049.1A CN201911110049A CN110747317B CN 110747317 B CN110747317 B CN 110747317B CN 201911110049 A CN201911110049 A CN 201911110049A CN 110747317 B CN110747317 B CN 110747317B
- Authority
- CN
- China
- Prior art keywords
- vacuum
- ladle
- vacuum tank
- cover
- tank cover
- 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 - Fee Related
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 31
- 239000010959 steel Substances 0.000 claims description 31
- 238000007670 refining Methods 0.000 claims description 22
- 238000007664 blowing Methods 0.000 claims description 21
- 238000007789 sealing Methods 0.000 claims description 19
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 16
- 239000001301 oxygen Substances 0.000 claims description 16
- 229910052760 oxygen Inorganic materials 0.000 claims description 16
- 238000005086 pumping Methods 0.000 claims description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 14
- 229910052786 argon Inorganic materials 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 230000006835 compression Effects 0.000 description 4
- 238000007906 compression Methods 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 238000007666 vacuum forming Methods 0.000 description 1
Images
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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
-
- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0075—Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
-
- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/072—Treatment with gases
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention relates to a ladle type vacuum refining furnace, which comprises a vacuum pumping pipeline, an oxygen blowing gun, a vacuum charging hopper, a vacuum base and a vacuum tank cover, wherein the vacuum pumping pipeline is arranged on the vacuum charging hopper; the vacuum base is cylindrical and the top of the vacuum base is provided with an opening; the vacuum tank cover is cylindrical, the bottom of the vacuum tank cover is provided with an opening, and the vacuum tank cover and the vacuum base are arranged up and down correspondingly; the vacuumizing pipeline comprises a branch pipe and is communicated with the vacuum tank cover and the inside of the vacuum base through the branch pipe; the air outlet of the oxygen blowing lance is arranged in the vacuum tank cover; the vacuum charging hopper is arranged above the vacuum tank cover and is communicated with the inside of the vacuum tank cover. In the invention, the vacuum base and the vacuum tank cover are utilized to only cover the bottom and the upper part of the steel ladle without completely coating the steel ladle; the time for forming a vacuum environment is short, the refining of the molten steel can be carried out as fast as possible, the temperature drop in the process is small, the refining quality of the molten steel is favorably ensured, and the method is suitable for small-sized ladles.
Description
Technical Field
The invention relates to a refining furnace, in particular to a ladle type vacuum refining furnace.
Background
The vacuum refining furnace is used for refining molten steel under vacuum.
Referring to fig. 1, the prior art apparatus is in the form of a "pot" refining furnace, i.e., a ladle 2 containing molten steel is placed in a vacuum vessel 1, and a vacuum is formed in the vacuum vessel 1, so as to refine the molten steel in the ladle under vacuum.
The tank type refining furnace comprises a vacuum tank 1, and a vacuum-pumping pipeline 3 for pumping air in the tank is communicated with the vacuum tank 1; an oxygen blowing lance 4 for blowing oxygen into the vacuum tank 1 is arranged in the vacuum tank, the upper end of the oxygen blowing lance 4 is positioned outside the tank body, and the lower end of the oxygen blowing lance is positioned in the tank body; the top of the vacuum tank 1 is provided with a vacuum feeding hopper 5 for feeding and an observation hole 6 for observing the refining condition, and the observation hole 6 is sealed and does not leak gas. During refining, the ladle 2 is placed into the vacuum tank 1, and the lower end of the oxygen blowing lance 4 and the discharge hole of the vacuum charging hopper 5 correspond to the top opening of the ladle cover 20. The lower part of the ladle 2 is provided with an argon blowing port 22 for blowing in argon; the lower part of the ladle 2 is also provided with a pouring gate 24 for pouring molten steel.
One problem with current use of such "can" refiners is that they require a large enough tank volume to hold a ladle 2 containing molten steel; thus, the time for forming the vacuum in the vacuum tank 1 is long, and more importantly, the temperature drop of the steel ladle in the large vacuum tank 1 is large in the vacuum forming and subsequent vacuum refining processes; this is more severe for smaller ladles; the general tank type vacuum refining furnace is suitable for ladles above 30 t; for the majority of foundries, especially for the casting of special steel, the used steel ladle 2 is 2-20t mostly, and the adaptability of the two is poor.
Disclosure of Invention
The invention aims to provide a ladle type vacuum refining furnace which is better matched with a small rigid ladle.
The above object of the present invention is achieved by the following technical solutions: a ladle type vacuum refining furnace comprises a vacuum pumping pipeline, an oxygen blowing gun, a vacuum charging hopper, a vacuum base and a vacuum tank cover; the vacuum base is cylindrical and the top of the vacuum base is provided with an opening; the vacuum tank cover is cylindrical, the bottom of the vacuum tank cover is provided with an opening, and the vacuum tank cover and the vacuum base are arranged up and down correspondingly; the vacuumizing pipeline comprises a branch pipe and is communicated with the vacuum tank cover and the inside of the vacuum base through the branch pipe; the air outlet of the oxygen blowing lance is arranged in the vacuum tank cover; the vacuum charging hopper is arranged above the vacuum tank cover and is communicated with the inside of the vacuum tank cover.
By adopting the technical scheme, when in use, the lower part of the ladle is supported on the vacuum base and forms a closed space with the vacuum base in an enclosing way; the vacuum tank cover is buckled at the upper part of the steel ladle and forms a closed space with the upper part of the steel ladle in a surrounding way; the vacuumizing pipeline works to form a vacuum environment at the upper part and the lower part of the ladle; oxygen can be blown in from the opening of the ladle cover through the oxygen blowing lance; the discharge gate of vacuum loading hopper corresponds the opening of ladle cover, can feed in the use.
Compared with the prior art, the vacuum base and the vacuum tank cover only need to cover the bottom and the upper part of the steel ladle, and do not need to completely coat the steel ladle; the time for forming a vacuum environment is short, the refining of the molten steel can be carried out as fast as possible, the temperature drop in the process is small, the refining quality of the molten steel is favorably ensured, and the method is suitable for small ladles.
The invention is further configured to: and a circle of elastic compensating flange is arranged at the lower edge of the vacuum tank cover.
By adopting the technical scheme, in actual use, the ladle has better sealing property with the vacuum base by means of self weight; the vacuum tank cover can not be placed on the ladle by the self weight of the vacuum tank cover, so that the strength of the ladle is influenced; the vacuum tank cover is suitable for completing sealing with a steel ladle without excessive pressure pressing on the steel ladle, which brings more difficulty to the lifting adjustment of the vacuum tank cover; the elastic compensation flange is arranged, so that the vacuum tank cover can be adjusted more conveniently.
The invention is further configured to: the compensation flange comprises a support ring, a pressure spring and a top ring; the supporting ring and the top ring are annular; the pressure spring is annular, the cross section of the pressure spring is U-shaped, and two side plate surfaces of the pressure spring are respectively connected with the support ring and the top ring; the top ring is fixedly connected to the lower edge of the vacuum tank cover; the upper part of the ladle is provided with a circle of annular ladle flange, and the support ring is supported on the ladle flange.
By adopting the technical scheme, the pressure spring can deform up and down when being pressed, the sealing performance is kept, meanwhile, the allowance for adjusting the vacuum tank cover up and down is provided, the adjustment of the vacuum tank cover is not required to be accurate, and the adjustment is more convenient.
The invention is further configured to: the U-shaped opening of the pressure spring is arranged outwards.
Through adopting above-mentioned technical scheme, the deformability of pressure spring can be better.
The invention is further configured to: a circle of vertical plate is fixedly arranged on the steel ladle flange, and a gap for deformation of the pressure spring is reserved between the upper end of the vertical plate and the top ring.
By adopting the technical scheme, in actual use, the pressure spring can be excessively deformed along with the increase of the use time or abnormal use; in order to protect the pressure spring, a circle of vertical plates are fixedly arranged on the steel ladle flange, and a gap for deformation of the pressure spring is reserved between the upper ends of the vertical plates and the top ring; after the arrangement, when the pressure spring is excessively deformed, the vertical plate can support the top ring to prevent the pressure spring from excessively deforming.
The invention is further configured to: an embedding groove is formed in the lower surface of the support ring along the circumferential direction, a sealing strip is arranged in the embedding groove, and the lower surface of the sealing strip is exposed out of the embedding groove.
Through adopting above-mentioned technical scheme, during the use, the lower surface of sealing strip can butt on the ladle flange, and the cooperation support ring lower surface plays sealed effect.
The invention is further configured to: the caulking groove is of a necking structure.
By adopting the technical scheme, the sealing strip is conveniently clamped.
In conclusion, the invention has the following beneficial effects:
1. the vacuum base and the vacuum tank cover only need to cover the bottom and the upper part of the steel ladle, and the steel ladle does not need to be completely coated; the time for forming a vacuum environment is short, the refining of the molten steel can be carried out as fast as possible, the temperature drop in the process is small, the refining quality of the molten steel is favorably ensured, and the method is suitable for small ladles;
2. the elastic compensation flange is arranged, so that the vacuum tank cover can be adjusted more conveniently.
Drawings
FIG. 1 is a sectional view of a prior art ladle vacuum refining furnace;
FIG. 2 is a sectional view of the ladle vacuum refining furnace in the present embodiment;
fig. 3 is an enlarged view of a portion a in fig. 2.
In the figure, 1, a vacuum tank; 2. a ladle; 20. covering the steel ladle; 21. a steel ladle flange; 22. an argon blowing port; 23. blowing an argon tube; 24. a casting gate; 3. vacuumizing the pipeline; 4. blowing an oxygen lance; 5. a vacuum hopper; 6. an observation hole; 7. a vacuum base; 8. a vacuum tank cover; 9. a compensating flange; 90. a support ring; 900. caulking grooves; 91. a pressure spring; 92. a top ring; 93. a vertical plate; 94. a sealing strip.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Examples
Referring to fig. 2, a ladle type vacuum refining furnace comprises a vacuum pumping pipeline 3, an oxygen blowing lance 4, a vacuum charging hopper 5, a vacuum base 7 and a vacuum tank cover 8; the vacuum base 7 is cylindrical and is provided with an opening at the top; the vacuum tank cover 8 is cylindrical, the bottom of the vacuum tank cover is provided with an opening, and the vacuum tank cover 8 and the vacuum base 7 are arranged up and down correspondingly; the vacuum-pumping pipeline 3 comprises a branch pipe and is communicated with the interior of the vacuum tank cover 8 and the vacuum base 7 through the branch pipe; the air outlet of the oxygen blowing lance 4 is arranged in the vacuum tank cover 8; the vacuum hopper 5 is disposed above the vacuum pot cover 8 and communicates with the inside of the vacuum pot cover 8.
When in use, the lower part of the ladle 2 is supported on the vacuum base 7 and forms a closed space with the vacuum base 7; the vacuum tank cover 8 is buckled at the upper part of the steel ladle 2 and forms a closed space with the upper part of the steel ladle 2 in a surrounding way; the vacuum pumping pipeline 3 works to form vacuum environments at the upper part and the lower part of the ladle 2; oxygen can be blown in from the opening of the ladle cover 20 through the oxygen blowing lance 4; the discharge hole of the vacuum charging hopper 5 corresponds to the opening of the ladle cover 20, and charging can be carried out in the using process.
Compared with the prior art, the vacuum base 7 and the vacuum tank cover 8 only need to cover the bottom and the upper part of the ladle 2, and the ladle 2 does not need to be completely coated; the time for forming the vacuum environment is short, the molten steel can be refined as fast as possible, the temperature drop in the process is small, and the refining quality of the molten steel is guaranteed. The application is suitable for the use of small ladles 2.
The bottom of the ladle 2 is provided with an argon blowing port 22 and is communicated with an argon blowing pipe 23, and the other end of the argon blowing pipe 23 is positioned outside the vacuum base 7. When the ladle 2 is to be taken out, the vacuum vessel cover 8 is opened upward, and then the ladle 2 is lifted and the molten steel is poured from the opening thereof, which is a small-sized ladle 2, in such a manner that the pouring of the molten steel is more convenient and the ladle 2 is structurally simpler.
In practical use, the ladle 2 has better sealing property with the vacuum base 7 by means of self weight; the vacuum can cover 8 cannot be reproduced on the ladle 2 in its own right, which affects the strength of the ladle 2; the vacuum vessel lid 8 is preferably sealed to the ladle 2 without excessive pressure on the ladle 2, which makes it difficult to adjust the elevation of the vacuum vessel lid 8.
With reference to fig. 2 and 3, in order to improve on the above-mentioned problem, a compensating flange 9 is designed in the present application.
Specifically, the compensating flange 9 comprises a support ring 90, a pressure spring 91 and a top ring 92; the support ring 90 and the top ring 92 are annular; the pressure spring 91 is annular, the cross section of the pressure spring 91 is U-shaped, and two side plate surfaces of the pressure spring 91 are respectively connected with the support ring 90 and the top ring 92; the top ring 92 is fixedly connected to the lower edge of the vacuum tank cover 8; the upper part of the ladle 2 is provided with a ring-shaped ladle flange 21, and the support ring 90 is supported on the ladle flange 21.
Therefore, when the vacuum cup is used, the pressure spring 91 can deform up and down when being pressed, the sealing performance is kept, meanwhile, the allowance for the up-and-down adjustment of the vacuum cup cover 8 is provided, the adjustment of the vacuum cup cover 8 is not required to be accurate, and the adjustment is more convenient.
The U-shaped opening of the pressure spring 91 is arranged outwards; so that the deformability of the pressing spring 91 is better.
In actual use, the pressure spring 91 can be deformed excessively along with the increase of the use time or abnormal use; in order to protect the compression spring 91, a circle of vertical plate 93 is fixedly arranged on the ladle flange 21, and a gap for the compression spring 91 to deform is reserved between the upper end of the vertical plate 93 and the top ring 92; when the compression spring 91 is excessively deformed, the vertical plate 93 can support the top ring 92 to prevent the compression spring 91 from excessively deforming.
An embedding groove 900 is formed in the lower surface of the support ring 90 along the circumferential direction, a sealing strip 94 is arranged in the embedding groove 900, and the lower surface of the sealing strip 94 is exposed out of the embedding groove 900; when the sealing device is used, the lower surface of the sealing strip 94 is abutted to the ladle flange 21 and is matched with the lower surface of the support ring 90 to play a sealing role.
The sealing strip 94 is made of a flexible refractory material. The caulking groove 900 is a necking structure, which facilitates the clamping of the sealing strip 94.
The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.
Claims (1)
1. The utility model provides a ladle formula vacuum refining furnace, includes evacuation pipeline (3), oxygen blowing rifle (4), vacuum charging hopper (5), its characterized in that: the vacuum cup also comprises a vacuum base (7) and a vacuum cup (1) cover; the vacuum base (7) is cylindrical and the top of the vacuum base is provided with an opening; the cover of the vacuum tank (1) is cylindrical, the bottom of the vacuum tank is provided with an opening, and the cover of the vacuum tank (1) and the vacuum base (7) are arranged up and down correspondingly; the vacuum pumping pipeline (3) comprises a branch pipe and is communicated with the inside of the vacuum tank (1) cover and the vacuum base (7) through the branch pipe; the air outlet of the oxygen blowing lance (4) is arranged in the cover of the vacuum tank (1); the vacuum charging hopper (5) is arranged above the vacuum tank (1) cover and is communicated with the interior of the vacuum tank (1) cover; a circle of elastic compensation flange (9) is arranged on the lower edge of the cover of the vacuum tank (1); the compensation flange (9) comprises a support ring (90), a pressure spring (91) and a top ring (92); the support ring (90) and the top ring (92) are annular; the pressure spring (91) is annular, the cross section of the pressure spring is U-shaped, and two side plate surfaces of the pressure spring (91) are respectively connected with the support ring (90) and the top ring (92); the top ring (92) is fixedly connected to the lower edge of the cover of the vacuum tank (1); a ring-shaped flange of the ladle (2) is arranged at the upper part of the ladle (2), and the support ring (90) is supported on the flange of the ladle (2); the U-shaped opening of the pressure spring (91) is arranged outwards; a circle of vertical plates (93) are fixedly arranged on a flange of the steel ladle (2), and a gap for the deformation of the pressure spring (91) is reserved between the upper ends of the vertical plates (93) and the top ring (92); an embedded groove (900) is formed in the lower surface of the support ring (90) along the circumferential direction, a sealing strip (94) is arranged in the embedded groove (900), and the lower surface of the sealing strip (94) is exposed out of the embedded groove (900); the caulking groove (900) is of a necking structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911110049.1A CN110747317B (en) | 2019-11-14 | 2019-11-14 | Ladle type vacuum refining furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911110049.1A CN110747317B (en) | 2019-11-14 | 2019-11-14 | Ladle type vacuum refining furnace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110747317A CN110747317A (en) | 2020-02-04 |
| CN110747317B true CN110747317B (en) | 2021-07-13 |
Family
ID=69283147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911110049.1A Expired - Fee Related CN110747317B (en) | 2019-11-14 | 2019-11-14 | Ladle type vacuum refining furnace |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110747317B (en) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1433413A1 (en) * | 1962-04-18 | 1968-11-07 | Friedrich Krupp Ag | Tapping degassing pan seal |
| JPS58181829A (en) * | 1982-04-16 | 1983-10-24 | Sasebo Jukogyo Kk | Countermeasure device against slopping in in-ladle refining apparatus |
| FR2564861B1 (en) * | 1984-05-24 | 1989-03-10 | Stein Heurtey | POCKET COVER FOR TREATING LIQUID STEEL. |
| JP4772404B2 (en) * | 2005-07-12 | 2011-09-14 | 新日本製鐵株式会社 | Vacuum processing apparatus and sealing method thereof |
| CN201411470Y (en) * | 2009-06-09 | 2010-02-24 | 西安新达炉业工程有限责任公司 | Small tonnage environment-friendly VOD ladle refining furnace |
| CN202898459U (en) * | 2012-09-04 | 2013-04-24 | 树赢(国际)控股西安装备有限公司 | Convenient and practical vacuum degassing(VD) refining furnace |
| CN103589823B (en) * | 2013-11-30 | 2015-08-05 | 西安新达炉业工程有限责任公司 | Integration ladle refining equipment and method for making steel |
| CN203582895U (en) * | 2013-11-30 | 2014-05-07 | 西安新达炉业工程有限责任公司 | Integrated ladle refining equipment |
-
2019
- 2019-11-14 CN CN201911110049.1A patent/CN110747317B/en not_active Expired - Fee Related
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| Publication number | Publication date |
|---|---|
| CN110747317A (en) | 2020-02-04 |
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