CN110842163A - Wire feeding method and device for reducing oxygen content of rare earth wire - Google Patents
Wire feeding method and device for reducing oxygen content of rare earth wire Download PDFInfo
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- CN110842163A CN110842163A CN201910939341.8A CN201910939341A CN110842163A CN 110842163 A CN110842163 A CN 110842163A CN 201910939341 A CN201910939341 A CN 201910939341A CN 110842163 A CN110842163 A CN 110842163A
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- rare earth
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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
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
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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
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/108—Feeding additives, powders, or the like
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
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Abstract
The invention relates to a wire feeding method and a device for reducing the oxygen content of rare earth wires, wherein in the wire feeding process of continuous casting molten steel, a rare earth wire coil is arranged on a wire coil wheel, the rare earth wires are drawn out to pass through a wire scraping device to remove a surface oxide layer, and the wires are fed through a wire feeding machine; placing an isolation hood in the crystallizer, and immersing part of the isolation hood into the casting powder and the molten steel to seal and isolate a small part of the casting powder; the rare earth wires are inserted into the casting powder and the molten steel inside the isolation cover through the guide steel pipe in the middle of the isolation cover, the rare earth wires are in contact with the casting powder inside the isolation cover, and the casting powder outside the isolation cover is not in direct contact with the rare earth wires. The invention purifies the rare earth wires in the process of feeding the molten steel, avoids harmful impurities generated after the rare earth wires with low purity are fed into the steel, and plays the beneficial effects of improving the strength, toughness, corrosion resistance and the like of the steel by the rare earth.
Description
Technical Field
The invention relates to the field of ferrous metallurgy, in particular to a wire feeding method and a wire feeding device for reducing the oxygen content of rare earth wires.
Background
The rare earth added into the steel can play a role in modifying and microalloying the inclusions, and can improve the strength, toughness, corrosion resistance and other properties of the steel. In China, rare earth treated steel has wide development space. At present, the continuous casting process is generally adopted to produce billets, and the method for adding rare earth mainly adopts a crystallizer wire feeding method. However, because the oxygen content in rare earth is always high, the purity often cannot meet the process requirements, and large-particle inclusions are generated after feeding, so that the performance of continuous casting billets is reduced.
In the present continuous steel casting process, the only feasible process for adding rare earth into steel is a process for feeding rare earth wires into molten steel of a crystallizer. The rare earth-containing steel has high requirement on the total oxygen content of the rare earth wires, and the total oxygen content is required to be lower than 30 ppm. Rare earth is chemically very active and is easily oxidized, has higher reactivity with oxygen than aluminum, begins to form an oxide layer after a few minutes of exposure to air, and the thickness of the oxide layer increases with time. Therefore, the surface oxidation layer is inevitable in the process of preparing and storing the rare earth wire. Through detection, the oxygen content of the surface oxide layer of the rare earth wire accounts for more than 60 percent of the total oxygen content of the rare earth wire.
How to improve the purity of the rare earth wire and reduce the oxygen content of the rare earth wire to an ideal level is always the main research content of metallurgical workers.
Disclosure of Invention
The invention aims to solve the technical problem of providing a wire feeding method and a wire feeding device for reducing the oxygen content of rare earth wires, solving the problem of low purity of the rare earth wires used in the prior continuous casting steel, avoiding harmful impurities generated after the low-purity rare earth wires are fed into the steel, and playing the beneficial effects of rare earth in improving the strength, toughness, corrosion resistance and the like of the steel.
In order to achieve the purpose, the invention adopts the following technical scheme:
a wire feeding method for reducing the oxygen content of rare earth wires is characterized in that in the wire feeding process of continuous casting molten steel, surface oxide layers of the rare earth wires are removed, the rare earth wires are inserted into covering slag and the inner molten steel which are sealed and isolated by an isolation cover in a crystallizer through a guide steel pipe, and the process comprises the following steps:
1) mounting the rare earth wire coil on a rare earth wire coil wheel, drawing rare earth wires, passing the rare earth wires through a wire scraping device to remove a surface oxide layer, and feeding the wires through a wire feeding machine;
2) placing an isolation hood in the crystallizer, and immersing part of the isolation hood into the casting powder and the molten steel to seal and isolate a small part of the casting powder;
3) the rare earth wires are inserted into the casting powder and the molten steel inside the isolation cover through the guide steel pipe in the middle of the isolation cover, the rare earth wires are in contact with the casting powder inside the isolation cover, and the casting powder outside the isolation cover is not in direct contact with the rare earth wires.
The wire feeding device for reducing the oxygen content of the rare earth wires comprises a rare earth wire winding wheel, a wire scraping device, a wire feeding machine and an isolation cover, wherein the middle part of the isolation cover is in threaded connection with a guide steel pipe.
The isolation cover comprises a positioning disc and isolation cups, the isolation cups are sleeved outside the positioning disc, and vent holes communicated with the outside are formed in the contact surfaces of the positioning disc and the isolation cups.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention purifies the rare earth wires in the process of feeding the molten steel, avoids harmful impurities generated after feeding the low-purity (high oxygen content) rare earth wires into the steel, and plays the beneficial effects of improving the strength, toughness, corrosion resistance and the like of the steel by the rare earth.
2. After the surface oxide layer of the rare earth wire is removed, the bare rare earth wire is directly contacted with the covering slag when being fed into the molten steel of the crystallizer, and the bare rare earth wire and the molten steel react with each other to deteriorate the performance of the covering slag in the crystallizer, so that the function of the covering slag is lost, and the continuous casting cannot be continued. The invention adopts a process of sealing and isolating a small part of the casting powder contacted with the rare earth wires, so that most of the casting powder is not influenced by the rare earth wires, the continuous casting is smooth, the function is realized by using the isolation cover, and the problem is successfully solved.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a schematic structural diagram of the isolation hood.
In the figure: the device comprises a rare earth wire winding wheel 1, a wire scraping device 2, a wire feeding machine 3, an isolation cover 4, a guide steel pipe 5, a positioning disc 41, an isolation cup 42 and a vent hole 43.
Detailed Description
The following further describes embodiments of the present invention with reference to the accompanying drawings:
referring to fig. 1-2, the wire feeding device for reducing the oxygen content of the rare earth wire comprises a rare earth wire winding wheel 1, a wire scraping device 2, a wire feeding machine 3 and an isolation cover 4, wherein the middle part of the isolation cover 4 is in threaded connection with a guide steel pipe 5.
The isolation cover 4 comprises a positioning plate 41 and isolation cups 42, the isolation cups 42 are sleeved outside the positioning plate 41, and vent holes 43 communicated with the outside are arranged on the contact surface of the positioning plate 41 and the isolation cups 42.
A wire feeding method for reducing the oxygen content of rare earth wires is characterized in that in the wire feeding process of continuous casting molten steel, surface oxide layers of the rare earth wires are removed, and the rare earth wires are inserted into closed and isolated covering slag in a crystallizer and the internal molten steel through a guide steel pipe, and the process comprises the following steps:
1) mounting the rare earth wire coil on a wire coil wheel, drawing the rare earth wire to pass through a wire scraping device to remove a surface oxide layer, and feeding the wire by a wire feeding machine;
2) placing an isolation hood in the crystallizer, and immersing part of the isolation hood into the casting powder and the molten steel to seal and isolate a small part of the casting powder;
3) and (3) inserting the rare earth wires into the casting powder and molten steel in the isolation cover through a guide steel pipe in the middle of the isolation cover, wherein the rare earth wires are in contact with the casting powder in the isolation cover, and the casting powder outside the isolation cover is not in direct contact with the rare earth wires.
The total oxygen content of the rare earth wire with the surface oxide layer removed is 0.0019-0.0021 percent.
The wire feeding speed of the wire feeding machine is 170 mm/s-200 mm/s.
The depth of the rare earth wire entering the molten steel is 25 mm-30 mm.
The wire feeding process comprises the following steps:
1. mounting the rare earth wire coil on a wire coil wheel;
2. drawing rare earth wires to respectively pass through the wire scraping device, the wire feeding machine and the guide steel pipe;
3. placing the isolation hood in a crystallizer, and partially immersing the isolation hood into the casting powder and the molten steel;
4. the wire feeding machine is inching to move the rare earth wires a little, and the wire scraping device enables the wire scraping thickness of the rare earth wires to reach a target value;
5. the wire feeder is started, and the roller drives the rare earth wires to move in the direction indicated by the arrow in the figure. The rare earth wire passes through the wire scraping device, and the surface oxide layer is scraped, so that the purified rare earth wire is obtained. The rare earth wires are inserted into the covering slag and the molten steel in the isolation cup through the guide steel pipe until the wire feeding is finished.
Example 1
Steel grade: the weathering steel 09CuPTiRE, the diameter of the rare earth wire is 2.5mm, the thickness of an oxide layer of the rare earth wire is 70 mu m, the radius of the isolation hood is 25mm, the continuous casting and drawing speed is 1.5m/min, and the section size of a casting blank is as follows: 230 x 1400mm, 3 pots of continuous casting, each pot weighing 180 tons of molten steel.
1. The rare earth wire coil is arranged on a wire coil wheel 1. Sampling and detecting the total oxygen content of the rare earth wires as follows: 0.0073 percent;
2. drawing rare earth wires to respectively pass through the wire scraping device 2, the wire feeding machine 3 and the guide steel pipe 5;
3. placing the isolation hood 4 in a crystallizer 6, and immersing the isolation hood into the casting powder 7 and the molten steel 8 to a depth of 25 mm;
4. the wire feeding machine 3 is inching to enable the rare earth wires to move a little, and the wire scraping device enables the wire scraping thickness of the rare earth wires to be 75-85 mu m; sampling and detecting the total oxygen content of the rare earth wires as follows: 0.0021%;
5. the wire feeding machine 3 is started, and the roller drives the rare earth wire 9 to move at the speed of 200 mm/s. The rare earth wires 9 are scraped by the wire scraping device 2 to a thickness of 85 μm. Thus, purified rare earth wires 9 are obtained. The rare earth wires 9 are inserted into the casting powder 7 and the molten steel 8 in the isolation cup 4 through the guide steel tube 5, and the wires are fed until the 3-pot continuous casting is finished.
And (3) taking a continuous casting billet sample, detecting inclusions in steel by using a metallographic microscope, and compared with the method of feeding common rare earth wires, reducing the content of the inclusions with the size of more than 50 mu m in the steel by 93.1 percent and improving the corrosion resistance of steel by 28.5 percent.
Example 2
Steel grade: ship plate steel E36, the diameter of the rare earth wire is 3.0mm, the thickness of the rare earth wire oxidation layer is 75 microns, the radius of the isolation hood is 30mm, the continuous casting and drawing speed is 1.0m/min, and the section size of the casting blank is as follows: 300 x 1550mm, continuously casting 4 pots, each of which is 100 tons of molten steel.
1. The rare earth wire coil is arranged on a wire coil wheel 1. Sampling and detecting the total oxygen content of the rare earth wires as follows: 0.0061%;
2. drawing rare earth wires to respectively pass through the wire scraping device 2, the wire feeding machine 3 and the guide steel pipe 5;
3. placing the isolation hood 4 in a crystallizer 6, and immersing the isolation hood into the casting powder 7 and the molten steel 8 to a depth of 30 mm;
4. the wire feeding machine 3 is inching to move the rare earth wire a little, the wire scraping device enables the wire scraping thickness of the rare earth wire to be 80-90 mu m, and the sampling detection on the total oxygen content of the rare earth wire is as follows: 0.0019%;
5. the wire feeding machine 3 is started, and the roller drives the rare earth wire 9 to move at the speed of 200 mm/s. The rare earth wires 9 are scraped by the wire scraping device 2 to a thickness of 90 μm. Thus, purified rare earth wires 9 are obtained. The rare earth wires 9 are inserted into the casting powder 7 and the molten steel 8 in the isolation cup 4 through the guide steel tube 5, and the wires are fed until the 3-pot continuous casting is finished.
The foregoing is considered as illustrative only of the principles of the invention and is not to be in any way limiting, since all equivalent changes and modifications are intended to be included within the scope of the appended claims.
Claims (3)
1. A wire feeding method for reducing the oxygen content of rare earth wires is characterized in that in the wire feeding process of continuous casting molten steel, surface oxide layers of the rare earth wires are removed, the rare earth wires are inserted into covering slag and the inner molten steel which are sealed and isolated by an isolation cover in a crystallizer through a guide steel pipe, and the process comprises the following steps:
1) mounting the rare earth wire coil on a rare earth wire coil wheel, drawing rare earth wires, passing the rare earth wires through a wire scraping device to remove a surface oxide layer, and feeding the wires through a wire feeding machine;
2) placing an isolation hood in the crystallizer, and immersing part of the isolation hood into the casting powder and the molten steel to seal and isolate a small part of the casting powder;
3) the rare earth wires are inserted into the casting powder and the molten steel inside the isolation cover through the guide steel pipe in the middle of the isolation cover, the rare earth wires are in contact with the casting powder inside the isolation cover, and the casting powder outside the isolation cover is not in direct contact with the rare earth wires.
2. The utility model provides a reduce wire feeding device of tombarthite silk oxygen content which characterized in that, includes tombarthite silk winding up wheel, scrapes silk device, wire feeding machine, each part of cage, the middle part and the direction steel pipe threaded connection of cage.
3. The wire feeding device for reducing the oxygen content of the rare earth wires according to claim 2, wherein the isolation cover comprises a positioning plate and isolation cups, the isolation cups are sleeved outside the positioning plate, and vent holes communicated with the outside are formed in the contact surface of the positioning plate and the isolation cups.
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| CN201910939341.8A CN110842163A (en) | 2019-09-30 | 2019-09-30 | Wire feeding method and device for reducing oxygen content of rare earth wire |
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| CN201910939341.8A CN110842163A (en) | 2019-09-30 | 2019-09-30 | Wire feeding method and device for reducing oxygen content of rare earth wire |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113403449A (en) * | 2021-06-11 | 2021-09-17 | 山西太钢不锈钢股份有限公司 | Production method for wide steel strip iron-chromium-aluminum continuous casting slab rare earth alloying |
| CN114769530A (en) * | 2022-03-29 | 2022-07-22 | 鞍钢股份有限公司 | Device for reducing oxygen content of rare earth wire added into steel |
| CN115592084A (en) * | 2022-10-25 | 2023-01-13 | 东北大学（Cn） | Method for high-speed continuous casting of super austenitic stainless steel plate blank |
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| CN113403449A (en) * | 2021-06-11 | 2021-09-17 | 山西太钢不锈钢股份有限公司 | Production method for wide steel strip iron-chromium-aluminum continuous casting slab rare earth alloying |
| CN114769530A (en) * | 2022-03-29 | 2022-07-22 | 鞍钢股份有限公司 | Device for reducing oxygen content of rare earth wire added into steel |
| CN115592084A (en) * | 2022-10-25 | 2023-01-13 | 东北大学（Cn） | Method for high-speed continuous casting of super austenitic stainless steel plate blank |
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Application publication date: 20200228 |