CN110802222A - Vacuum induction pouring tundish - Google Patents
Vacuum induction pouring tundish Download PDFInfo
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- CN110802222A CN110802222A CN201810881727.3A CN201810881727A CN110802222A CN 110802222 A CN110802222 A CN 110802222A CN 201810881727 A CN201810881727 A CN 201810881727A CN 110802222 A CN110802222 A CN 110802222A
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- slag
- weir
- tundish
- dam
- flow channel
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
The invention discloses a vacuum induction pouring tundish, which prolongs the retention time of molten steel in the tundish and changes the flowing property of the molten steel in the tundish by unique L-shaped tundish design and adding a slag-stopping weir, so that the molten steel is changed from a turbulent flow state into a laminar flow state in a transition zone, slag particles and impurities float to the surface of the molten steel for sufficient time and are stopped by the slag-stopping weir and the slag-stopping weir, the quality of the molten steel is finally improved, and the requirement of high purity is met.
Description
Technical Field
The invention relates to a corrosion detection method, in particular to a vacuum induction pouring tundish.
Background
The vacuum induction melting technology is a special metallurgical melting means for melting materials by utilizing electromagnetic induction to generate eddy current under the condition of high vacuum. The method is usually used for smelting high-value-added steel grades such as high-temperature alloy, high-alloy steel and the like, has extremely high requirement on purity, and is required to avoid abnormal conditions such as slag inclusion, excessive inclusion content and the like. During normal smelting and pouring, molten steel is poured into a tundish from a crucible in a smelting chamber and then flows into an ingot mould from a steel outlet of the tundish. Due to the particularity of the vacuum induction furnace equipment, special slag removing equipment such as a slag raking machine and a slag blocking ball is lacked, so that the purity of the vacuum induction furnace equipment to a great extent depends on the slag blocking effect of the pouring tundish.
In recent years, vacuum induction furnaces have been becoming larger, and 25-30t furnaces are not uncommon, and related products have made higher and higher demands on purity. The larger the capacity of the tundish is, the more molten steel is contained, and the more impurities are contained in the molten steel, so that the design of the large tundish with good slag stopping effect is very important for improving the purity of the product.
The structure of the conventional tundish is shown in figure 1, and specifically comprises the following steps:
a ladle 11 for bearing molten steel, the middle of the interior of which is provided with a refractory lining; a slag dam 12 is fixed on one side of molten steel entering the steel ladle, the top of the slag dam is close to the ladle opening of the steel ladle 11, and a certain gap is formed between the bottom of the slag dam and the inner bottom plate of the steel ladle 11, so that the slag dam plays a first blocking role on the steel slag in the molten steel.
A slag dam 13 which is arranged at a certain distance is arranged behind the first slag dam 12, and the bottom of the slag dam 13 is fixedly connected with the bottom plate in the ladle 11 so as to further block the steel slag in the molten steel. The height of the slag dam 13 is slightly higher than the gap at the bottom of the slag dam 12, and the distance between the two is relatively long, about 300 mm and 400 mm. A second slag retaining weir 14 is arranged behind the slag retaining dam 13, the top of the second slag retaining weir is close to the ladle opening of the ladle 11, and a certain gap is formed between the bottom of the second slag retaining weir and the inner bottom plate of the ladle 11, so that the second slag retaining weir can finally block steel slag in molten steel.
A molten steel outlet 15 is arranged at the bottom of one side of the molten steel in the ladle 11.
As shown by a dotted arrow in fig. 1, the molten steel flows in the conventional tundish structure, flows into the tundish from a tundish I region (a region in front of the slag weir 12), flows into a tundish II region (a region between the slag weir 12 and the slag weir 14, which belongs to a transition region) through a gap between the slag weir 12 and the bottom plate of the ladle, finally flows into a tundish III region through a gap between the slag weir 14 and the bottom plate, and flows out from a molten steel outlet 15 for casting.
The existing tundish design has a good blocking effect on large-size slag inclusion, and can basically block the area of the tundish I, II. However, for small-particle slag inclusion (slag particles smaller than the gap between the slag dam and the slag weir), because of the design defect, the molten steel is still in a semi-turbulent state in the tundish II area, and the molten steel is difficult to float upwards within enough time.
Disclosure of Invention
The invention aims to solve the defects and provides a vacuum induction pouring tundish which can quickly and accurately evaluate the corrosion resistance of an electric heating pipe material for a water heater.
In order to achieve the above object, the present invention adopts the following technical solutions.
A vacuum induction pouring tundish with anti-corrosion and anti-wear properties comprises a ladle body which is formed by connecting a right rectangular chamber and a left rectangular chamber and is L-shaped when viewed from above, a partition plate is arranged in the right rectangular chamber, the right rectangular chamber is separated into a right full turbulent flow channel and a left laminar flow channel through the partition plate, a space is reserved between the partition plate and the inner wall of the right rectangular chamber, so that the right full turbulent flow channel is communicated with the left laminar flow channel at the tail end of the left laminar flow channel, a molten steel outlet is arranged at the tail part of the left rectangular chamber, the head part of the left rectangular chamber is horizontally vertical to the left laminar flow channel and is communicated with the tail part of the left laminar flow channel, a first slag dam is arranged at the tail end communication part of the right full turbulent flow channel and the left laminar flow channel, a second slag dam is arranged in the left laminar flow channel, a third slag dam is arranged in the left rectangular, and a second slag retaining dam is arranged behind the third slag retaining weir.
The first slag dam and the second slag dam are separated by a distance L1, and L1 is 30-100 mm.
The bottom gap heights of the first slag retaining weir, the second slag retaining weir and the third slag retaining weir are all H2, and H2 is 20-80 mm.
The height of the first slag dam is higher than the height of the gap at the bottom of the second slag dam by H1, and H1 is 20-80 mm.
The distance between the second slag dam and the first slag dam is larger than the distance between the third slag dam and the second slag dam by 1-10mm, and the height of the second slag dam is higher than that of the first slag dam by 2-10 mm.
The width L2 of the first slag weir is controlled at 200-400 mm.
The distance between the second slag weir and the inner wall of the head part of the left laminar flow channel is L3, and L3 is 600-1500 mm.
The distance between the second slag weir and the inner wall of the tail part of the left laminar flow channel is L4, and L4 is 1000 mm.
The distance between the third slag weir and the molten steel outlet is L5, and L5 is 200-400 mm.
And a distance L6 is reserved between one end of the second slag dam and the side wall of the left rectangular chamber, and L6 is 30 mm.
By adopting the vacuum induction pouring tundish, the residence time of the molten steel in the tundish is prolonged and the flowing property of the molten steel in the tundish is changed through the unique L-shaped tundish design and the addition of the slag-stopping dam, so that the molten steel is changed from a turbulent state to a laminar state in a transition zone, slag particles and impurities float to the surface of the molten steel for sufficient time and are stopped by the slag-stopping dam and the slag-stopping dam, the quality of the molten steel is finally improved, and the requirement of high purity is met.
Drawings
FIG. 1 is a cross-sectional view of a prior art tundish construction;
FIG. 2 is a top view of the vacuum induction casting tundish of the present invention;
fig. 3 is a schematic view of the structure between the dam and the weir of the present invention.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings.
As shown in figure 2, in order to prolong the residence time of molten steel in the tundish, the vacuum induction casting tundish with the corrosion and wear resistance is designed into an L shape, and the method specifically comprises the following steps: the bag comprises a bag body 21 which is formed by connecting a right rectangular chamber and a left rectangular chamber and is L-shaped when viewed from above, the bag body 21 is used for carrying molten steel, a fireproof lining is arranged in the bag body, a partition plate 1 is arranged in the right rectangular chamber, the right rectangular chamber is separated into a right full turbulent flow channel and a left laminar flow channel through the partition plate 1, a space is reserved between the partition plate 1 and the inner wall of the right rectangular chamber, so that the right full turbulent flow channel is communicated with the left laminar flow channel at the tail end of the right full turbulent flow channel, a molten steel outlet 27 is arranged at the tail part of the left rectangular chamber, the head part of the left rectangular chamber is horizontal and vertical to the left laminar flow channel and is communicated with the tail part of the left laminar flow channel, a first slag dam 22 is arranged at the tail end communication part of the right full turbulent flow channel and the left laminar flow channel, a second slag dam 23 is arranged in the left laminar flow channel, a third slag dam 25 is arranged, a second slag weir 26 is provided after the third slag weir 25. Wherein:
the distance between the first slag dam 24 and the second slag dam 23 is L1, and L1 is 30-100 mm. When the distance between L1 and L1 is greater than 100, it is difficult to rapidly change the flow direction of molten steel and increase the residence time of molten steel. When L1 is less than 30, the distance is too close, so that the flow resistance of molten steel is large and the smooth casting is not facilitated.
The height of the bottom gap of the second slag weir 23 is H2, H2 is 20-80mm, and the height of the bottom gap of the first slag weir and the third slag weir can be consistent with the height of the bottom gap of the first slag weir and the third slag weir. When H2 is larger than 80, the gap is too large, so that the slag particle blocking effect is difficult to achieve; and when the H2 time gap is less than 20, the gap is too small, which causes the pouring to be influenced by too large molten steel flow resistance. The height of the first slag dam 24 is higher than the height of the gap at the bottom of the second slag dam 23 by a distance H1, and H1 is 20-80 mm. When H1 is less than 20, it is difficult to form an effective upwelling, resulting in insufficient floating time of inclusions, and when H1 is more than 80, the molten steel stays for too long time, which affects casting. The specific structure is schematically shown in FIG. 3.
In order to enhance the slag-stopping effect, the resistance coefficient between the third slag-stopping weir 25 and the second slag-stopping dam 26 is required to be higher than the resistance coefficient between the second slag-stopping weir 23 and the first slag-stopping dam 24. Therefore, the distance between the second slag dam 23 and the first slag dam 24 is designed to be slightly larger than the distance between the third slag dam 25 and the second slag dam 26, preferably 1-10mm larger. Meanwhile, the height of the second slag blocking dam 26 is slightly higher than that of the first slag blocking dam 24, preferably 2-10 mm. The upper ends of the first and second slag dams 24 and 26 are rounded to prevent molten steel from swirling while flowing.
The width L2 of the first slag weir 22 is controlled at 200-400mm, when the width is too narrow, the residence time of the molten steel in the ladle is too long, the temperature drop is serious, and the pouring is influenced; and too wide is disadvantageous for the slag-stopping effect.
The distance between the second slag weir 23 and the inner wall of the head part of the left laminar flow channel is L3, and L3 is 600-. When L3 is less than 600, the time that the molten steel is in a laminar state in the tundish II area is too short, which is not beneficial to floating, gathering and growing of inclusions; when the thickness is more than 1500mm, the molten steel stays for too long time, so that pouring is influenced.
The distance between the second slag weir 23 and the inner wall of the tail part of the left laminar flow channel is L4, and L4 is 1000 mm-. When L4 is less than 400, the time that the molten steel is in a laminar state in a tundish III area is too short to help inclusions float upwards; when the thickness is more than 1000mm, the temperature drop is serious and even the casting cannot be smoothly carried out due to the overlong residence time of the molten steel.
The distance between the third slag weir 25 and the molten steel outlet 27 is L5, and when the L5 is too small or too large, the tapping position is not favorable for the stability of pouring steel and pouring flow, the vortex flow is easy to generate and the like; therefore, L5 should be controlled to 200-. Meanwhile, in order to better control the flow of molten steel and prevent the pouring plug flow, a certain distance is reserved between one end of the second slag blocking dam 26 and the inner wall of the left rectangular chamber on the same side, and the length is about 30 mm.
In fig. 3, a dotted arrow indicates the flow direction of molten steel in the tundish, and the molten steel flows into the tundish from a tundish I area (right side area of the first slag weir 22), flows into a tundish II area (area between the first slag weir 22 and the second slag weir 23) through a gap between the first slag weir 22 and the ladle bottom plate, flows into a tundish III area (area between the second slag weir 23 and the third slag weir 25) through a gap between the second slag weir 23 and the ladle bottom plate, flows into a tundish IV area through a gap between the third slag weir 25 and the ladle bottom plate, and flows out from a molten steel outlet 27 for casting. Because the unique tundish design enables the molten steel to move in an S-shaped flow direction in the tundish, the residence time of the molten steel is prolonged, and the temperature drop condition of the molten steel is superior to that of a straight-flow design.
The design mode of the invention ensures that the molten steel is quickly changed into the laminar flow state of the areas II and III from the full turbulent flow state just before entering the area I. II. The space of the III zone belongs to the largest laminar flow area in the tundish, and most of large-size slag particles or impurities are blocked before the second slag weir; the inclusion or slag particles in the molten steel flowing into the tundish III area basically exist in smaller sizes, and the fine particles float upwards and are gathered to grow up in enough time so as to be blocked in front of the third slag dam, so that the molten steel finally entering the tundish IV area has higher purity and meets the extremely high requirements of high-temperature alloy, high-alloy steel and the like on the purity of products.
Tests prove that the vacuum induction pouring tundish designed by the invention can realize good slag blocking effect and meet the high purity requirement of related products. The vacuum induction pouring test is carried out by adopting four novel tundishes respectively, and the relevant size, the using effect and the comparison result with the original tundish are shown in tables 1, 2 and 3.
The test is to smelt a certain high-temperature alloy, the smelting furnace is a 25t vacuum induction furnace, and the smelting process is charging, melting period, refining period, alloying period and pouring. And finally, after the chemical components reach the standard, adjusting the casting temperature to 1480 ℃ for tapping.
The details of examples 1-4 are shown in the following table.
TABLE 1 Effect of the invention
Table 2 compares the effect of the original tundish and the rating results of the related steel ingot inclusions
TABLE 3 comparison of water model test results for original tundish and improved tundish
Therefore, the novel tundish designed by the invention has better slag stopping effect, and the comparison of the grading results of inclusions can also find that the tundish of the invention is more favorable for improving the purity of molten steel compared with the conventional tundish, and the water model result also reflects that the average residence time of the tundish of the invention for the molten steel is obviously prolonged compared with the original tundish.
It will be appreciated by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.
Claims (10)
1. A vacuum induction pouring tundish is characterized by comprising a ladle body which is formed by connecting a right rectangular chamber and a left rectangular chamber and is L-shaped in overlook, wherein a partition plate is arranged in the right rectangular chamber, the right rectangular chamber is divided into a right full turbulent flow channel and a left laminar flow channel by a partition plate, a space is reserved between the partition plate and the inner wall of the right rectangular chamber to ensure that the right full turbulent flow channel is communicated with the left laminar flow channel at the tail end of the right full turbulent flow channel, the tail part of the left rectangular chamber is provided with a molten steel outlet, the head part of the left rectangular chamber is horizontally vertical to the left laminar flow channel and is communicated with the tail part of the left laminar flow channel, a first slag weir is arranged at the tail-end communication position of the right full turbulent flow channel and the left laminar flow channel, a second slag weir is arranged in the left laminar flow channel, and a third slag weir is arranged in the left rectangular chamber, a first slag weir is arranged behind the second slag weir, and a second slag weir is arranged behind the third slag weir.
2. The vacuum induction casting tundish of claim 1, wherein: the first slag dam and the second slag dam are separated by a distance L1, and L1 is 30-100 mm.
3. The vacuum induction casting tundish of claim 1, wherein: the bottom gap heights of the first slag retaining weir, the second slag retaining weir and the third slag retaining weir are all H2, and H2 is 20-80 mm.
4. The vacuum induction casting tundish of claim 1, wherein: the height of the first slag dam is higher than the height of the gap at the bottom of the second slag dam by H1, and H1 is 20-80 mm.
5. The vacuum induction pouring tundish according to claim 1 or 2, wherein: the distance between the second slag dam and the first slag dam is larger than the distance between the third slag dam and the second slag dam by 1-10mm, and the height of the second slag dam is higher than that of the first slag dam by 2-10 mm.
6. The vacuum induction casting tundish of claim 1, wherein: the width L2 of the first slag weir is controlled at 200-400 mm.
7. The vacuum induction casting tundish of claim 1, wherein: the distance between the second slag weir and the inner wall of the head part of the left laminar flow channel is L3, and L3 is 600-1500 mm.
8. The vacuum induction casting tundish of claim 1, wherein: the distance between the second slag weir and the inner wall of the tail part of the left laminar flow channel is L4, and L4 is 1000 mm.
9. The vacuum induction casting tundish of claim 1, wherein: the distance between the third slag weir and the molten steel outlet is L5, and L5 is 200-400 mm.
10. The vacuum induction casting tundish of claim 1, wherein: and a distance L6 is reserved between one end of the second slag dam and the side wall of the left rectangular chamber, and L6 is 30 mm.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810881727.3A CN110802222B (en) | 2018-08-06 | 2018-08-06 | Vacuum induction pouring tundish |
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| CN201810881727.3A CN110802222B (en) | 2018-08-06 | 2018-08-06 | Vacuum induction pouring tundish |
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| CN110802222B CN110802222B (en) | 2021-03-23 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111306937A (en) * | 2020-04-02 | 2020-06-19 | 钢铁研究总院 | Launder and vacuum induction melting furnace |
| CN114734031A (en) * | 2022-04-11 | 2022-07-12 | 成都先进金属材料产业技术研究院股份有限公司 | Pouring chute of vacuum induction furnace and pouring method of vacuum induction smelting |
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| US4961563A (en) * | 1989-06-12 | 1990-10-09 | Inco Alloys International, Inc. | Tundish for ingot pouring |
| JPH0323044A (en) * | 1989-06-21 | 1991-01-31 | Kawasaki Steel Corp | Method and apparatus for pouring molten steel into tundish in continuous casting |
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| KR20120051410A (en) * | 2010-11-12 | 2012-05-22 | 주식회사 포스코 | Block for flowing molten steel and tundish using the same |
| CN104107905A (en) * | 2013-04-19 | 2014-10-22 | 宝钢特钢有限公司 | Slab continuous casting tundish |
| CN108555256A (en) * | 2018-06-11 | 2018-09-21 | 江苏集萃先进金属材料研究所有限公司 | A kind of devices and methods therefor improving vacuum induction ingot solidification quality |
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| JPS4825866B1 (en) * | 1970-12-03 | 1973-08-01 | ||
| US4961563A (en) * | 1989-06-12 | 1990-10-09 | Inco Alloys International, Inc. | Tundish for ingot pouring |
| JPH0323044A (en) * | 1989-06-21 | 1991-01-31 | Kawasaki Steel Corp | Method and apparatus for pouring molten steel into tundish in continuous casting |
| JPH06126393A (en) * | 1992-10-16 | 1994-05-10 | Kobe Steel Ltd | Tundish for continuous casting |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111306937A (en) * | 2020-04-02 | 2020-06-19 | 钢铁研究总院 | Launder and vacuum induction melting furnace |
| CN114734031A (en) * | 2022-04-11 | 2022-07-12 | 成都先进金属材料产业技术研究院股份有限公司 | Pouring chute of vacuum induction furnace and pouring method of vacuum induction smelting |
| CN114734031B (en) * | 2022-04-11 | 2023-12-15 | 成都先进金属材料产业技术研究院股份有限公司 | Pouring launder of vacuum induction furnace and pouring method of vacuum induction smelting |
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Effective date of registration: 20200522 Address after: 200940 room 1277, building 216, 1269 Shuishui Road, Baoshan District, Shanghai Applicant after: Baowu Special Metallurgy Co., Ltd Address before: 200940 No. 1269, Fisheries Road, Shanghai, Baoshan District Applicant before: BAOSTEEL SPECIAL STEEL Co.,Ltd. |
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