CN214250524U - Anti-leakage furnace body structure of direct current electric arc furnace with furnace bottom electrode - Google Patents
Anti-leakage furnace body structure of direct current electric arc furnace with furnace bottom electrode Download PDFInfo
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- CN214250524U CN214250524U CN202023012973.7U CN202023012973U CN214250524U CN 214250524 U CN214250524 U CN 214250524U CN 202023012973 U CN202023012973 U CN 202023012973U CN 214250524 U CN214250524 U CN 214250524U
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Abstract
The utility model discloses an anti-leakage furnace body structure of a direct current electric arc furnace with a furnace bottom electrode, wherein a graphite electrode and the furnace bottom electrode are connected above a molten pool slag limit in the furnace body to generate electric arcs to smelt materials in the furnace body, the furnace bottom electrode is connected and installed on a furnace bottom shell, a conducting strip is installed at the upper end of the furnace bottom electrode, and the conducting strip is conducted with a molten pool in the furnace body; the furnace body is built by refractory bricks and is also provided with a tap hole; the anode lead wiring terminal is connected with the furnace bottom electrode through an anode lead segment; the cooling circulation pipeline section is arranged at the bottom of the furnace body, and is embedded into the inner branch of the furnace bottom electrode and connected with the conducting strip. The utility model relates to a have pertinence to the structural feature of direct current electric arc furnace body, thoroughly stop the stove bottom seepage and violate the evil, provide the safety guarantee for direct current electric arc furnace's production, the utility model discloses rational in infrastructure ensures that stove bottom safety does not have the seepage, can adapt to the smelting technology demand of complicated material, has established solid foundation for developing direct current electric arc furnace smelting technique.
Description
Technical Field
The utility model relates to a nonferrous metallurgy and steelmaking field, especially a take antiseep furnace body structure of stove bottom electrode direct current electric arc furnace.
Background
A dc arc furnace is an arc furnace that uses dc power as an energy source. It is basically the same as AC electric arc furnace, and changes three-phase AC into single-phase DC to produce electric arc on the metal furnace charge between furnace bottom electrode (anode) and graphite electrode (cathode) for smelting. The main differences between dc arc furnaces and ac arc furnace installations are: the rectifying device is added, the furnace top graphite electrode is changed into one (cathode) from three, the furnace bottom electrode (anode) is added, and the like. The arrangement of the bottom electrode is the biggest characteristic of the direct current electric arc furnace and is one of the keys of success of the direct current smelting technology. Although the technology is advanced and feasible, the fireproof heat-insulating material is easy to be impacted by electromagnetism, the fireproof heat-insulating material is corroded and cracks appear after the pressure of the furnace bottom is increased, the anode lead of the electrode at the furnace bottom is influenced by expansion caused by heat and contraction caused by cold of the furnace temperature, the molten liquid in the molten pool in the furnace can seep out along the gaps and the periphery of the anode lead of the electrode at the furnace bottom, great influence is caused to the production and the direct-current smelting process technology, and the normal production and the safety cannot be guaranteed. Heretofore, when a dc arc furnace is used with a furnace type structure having a bottom electrode, such a furnace bottom failure in the event of leakage is difficult to solve. Therefore, the key point of adopting the technical scheme is how to prevent the easy leakage problem of the furnace bottom.
Usually, the anode input end of the electrode at the furnace bottom is introduced at the outer opening of the furnace shell. As the temperature in the furnace is as high as 1800-2000 ℃, the furnace bottom is bombarded by cathode electrons and the electromagnetic stirring force of materials in the furnace is acted, the refractory heat-insulating material of the furnace bottom is quickly changed after being affected by impact and temperature rise, cracks can be generated slowly, and molten pool melt can seep out of the furnace shell along the gaps through the input end of the anode lead of the furnace bottom after being melted. When the molten bath has serious leakage, the whole furnace bottom can be damaged or penetrated. Therefore, in general furnace body structures with furnace bottom electrodes, if effective anti-leakage cooling measures are adopted for temperature rise of the outer opening of the furnace shell and the shell part of the furnace bottom without the anode input end of the furnace bottom electrode, the aim of normal operation and process technology of direct current smelting is difficult to realize, and direct current furnaces with bottom electrodes without anti-leakage cooling measures are mainly maintained by a furnace supplementing technology in production and are often stopped. The anode current is transmitted into a molten pool through steel columns built in furnace bottom refractory materials, the tapping temperature in the furnace is 1600 ℃, the stainless steel tapping temperature is 1800 ℃, and the furnace bottom temperature is 250-500-1600-1800-2000 ℃ from the bottom to the slag limit respectively.
How to design a take antiseep furnace body structure of stove bottom electrode direct current electric arc furnace, have rational in infrastructure, with strong points, easy operation, maintain advantages such as simple and convenient, resistant magnetic force erodees, high temperature resistant, safe no seepage, long-lived, have very important meaning.
Disclosure of Invention
In order to solve the technical problem, the utility model provides a take bottom electrode direct current electric arc furnace's antiseep furnace body structure has solved bottom electrode seepage problem, realizes the needs of direct current electric arc furnace smelting process technical characteristic, has reached the good economic benefits of direct current electric arc furnace technique.
According to an aspect of the utility model, relate to a take antiseep furnace body structure of stove bottom electrode direct current electric arc furnace, including furnace body, molten bath sediment limit, graphite electrode and stove bottom electrode, the stove bottom electrode constitutes inside branch road, and the graphite electrode is connected above the molten bath sediment limit in the furnace body with stove bottom electrode and is produced electric arc and smelt the material in the furnace body, still includes stove bottom shell, resistant firebrick, taphole, positive pole lead wire binding post, positive pole lead wire section, conducting strip, cooling cycle pipeline section, and the stove bottom shell is the bottom of furnace body, the stove bottom electrode is connected and is installed on the stove bottom shell, and the conducting strip is installed to stove bottom electrode upper end, and the conducting strip switches on with the molten bath in the furnace body; the furnace body is built by refractory bricks and is also provided with a taphole; the anode lead wiring terminal is connected with the furnace bottom electrode through an anode lead segment; the cooling circulation pipeline section is arranged at the bottom of the furnace body, embedded into the inner branch of the furnace bottom electrode and connected with the conducting strip.
According to the utility model discloses an at least one embodiment still includes positive pole lead wire guard shield, positive pole lead wire section outside is equipped with positive pole lead wire guard shield, and positive pole lead wire guard shield is inside to be filled there is graphite refractory material.
According to at least one embodiment of the utility model, the positive pole lead wire guard shield is welded with sealed steel sheet with furnace body contact department and is sealed.
According to at least one embodiment of the present invention, the anode lead shield is higher than the slag limit of the molten bath in the furnace body.
The total height of the slag limit of the melting pool in the furnace is not higher than the height of the anode lead segment shield in normal production.
According to the utility model discloses an at least one embodiment, the cooling circulation pipeline section is equipped with cooling circulation pipeline import and cooling circulation pipeline export, cooling circulation pipeline import, cooling circulation pipeline export are worn out respectively from the furnace body and are located the furnace body both sides.
According to at least one embodiment of the present invention, the cooling circulation pipe section is provided with a cooling circulation pipe shield on the outside, and the cooling circulation pipe shield is filled with graphite refractory material on the inside.
According to at least one embodiment of the present invention, the fluid in the cooling circulation pipe section is water-cooled or air-cooled.
According to at least one embodiment of the present invention, the anode lead connecting terminal and the furnace body form a "U" shaped structure; the anode lead wiring terminal and the furnace body form an L-shaped structure; the anode lead wiring terminal and the furnace body form a T-shaped structure; the anode lead wiring terminal and the furnace body form a convex structure.
All the terminals, cooling circulation pipeline section ports and lead wire shields led in from the bottom of the furnace body shell are firmly connected to the furnace body bottom shell.
The upper end of the conducting strip and the molten pool form a discharge area, and the graphite electrode and the furnace bottom electrode are connected above the slag limit of the molten pool in the furnace body to generate electric arc for smelting materials in the furnace body.
The utility model discloses a substantive characteristics and progress are:
the structure of the direct current electric arc furnace is characterized in that only one electrode is arranged above the furnace top and is a negative electrode, and the electrode at the furnace bottom is a positive electrode. Its power supply system is different from AC arc furnace, and is equipped with rectifier and reactor, and the contacts mounted on the furnace bottom can be formed into current loop.
The utility model discloses take bottom electrode direct current electric arc furnace's antiseep furnace body structure, the design is simple, the preparation is simple and convenient, low in manufacturing cost, can stop the seepage and violate, for direct current electric arc furnace body provides production operation safety guarantee, has rational in infrastructure, resistant electromagnetic shock, ensures that bottom electrode safety does not have the seepage, smelts material strong adaptability, characteristics such as high temperature resistant smelting and extension furnace life are smelted. The utility model discloses a furnace body structure's beneficial effect does:
(1) the electric arc is stable and centralized, the molten pool is well stirred, the temperature in the furnace is uniformly distributed, and the erosion amount of the furnace lining is small;
(2) the current and voltage fluctuation is small, the impact on a power grid is reduced, and the service life of the cable is prolonged;
(3) the electrode consumption is less, and the ton electrode consumption is more than 50% less than that of an alternating current electric arc furnace;
(4) can meet the requirement of the technical characteristics of the smelting process of the direct-current electric arc furnace.
Through calculating, the utility model discloses a good economic benefits of direct current electric arc furnace technique: 1. the consumption of the graphite electrode is reduced by more than 50-60%; 2. the electric energy consumption is saved by 8-15%; 3. refractory materials are saved by 30-35%; 4. saving the cable material of the short network; 5. the problem of furnace bottom electrode leakage which cannot be solved so far is solved; 6. the molten bath melt obtains even stirring effect, improves the power factor, reduces the voltage flicker rate, reduces the noise and has obvious economic benefit.
Drawings
Fig. 1 is a schematic structural diagram of an embodiment of the present invention.
Fig. 2 is a schematic view of a "U" shape structure according to another embodiment of the present invention.
Fig. 3 is a schematic view of an "L" structure according to another embodiment of the present invention.
Fig. 4 is a schematic view of a T-shaped structure according to another embodiment of the present invention.
Fig. 5 is a schematic view of a "convex" structure according to another embodiment of the present invention.
Part numbers and names in the figures:
the device comprises a graphite electrode 1, an anode lead wiring terminal 2, an anode lead segment 3, an anode lead shield 4, a cooling circulation pipeline inlet 5, a sealing steel plate 6, a furnace bottom electrode 7, a conducting strip 8, a furnace bottom shell 9, a cooling circulation pipeline segment 10, a cooling circulation pipeline shield 11, a cooling circulation pipeline outlet 12, an iron outlet 13, refractory bricks 14 and a molten pool slag limit 15.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the invention. It should be noted that, for convenience of description, only the parts related to the present invention are shown in the drawings.
In the present invention, the embodiments and the features of the embodiments may be combined with each other without conflict. The present invention will be described in detail with reference to the accompanying drawings in conjunction with embodiments.
In at least one embodiment of the present invention, as shown in fig. 1, the present invention provides an anti-leakage furnace body structure of dc arc furnace with bottom electrode 7, comprising a furnace body, a molten pool slag limit 15, a graphite electrode 1 and a bottom electrode 7, wherein the bottom electrode 7 constitutes an internal branch, the graphite electrode 1 and the bottom electrode 7 are connected above the molten pool slag limit 15 in the furnace body to generate electric arc for smelting materials in the furnace body, the anti-leakage furnace body structure further comprises a bottom shell 9, a refractory brick 14, an iron outlet 13, an anode lead terminal 2, an anode lead segment 3, a conducting strip 8 and a cooling circulation pipeline segment 10, the bottom shell 9 is the bottom of the furnace body, the bottom electrode 7 is connected and installed on the bottom shell 9, the conducting strip 8 is installed on the top of the bottom electrode 7, and the conducting strip 8 is conducted with the molten pool in the furnace body; the furnace body is built by refractory bricks 14, and is also provided with an iron notch 13; the anode lead wiring terminal 2 is connected with a furnace bottom electrode 7 through an anode lead segment 3; the cooling circulation pipeline section 10 is arranged at the bottom of the furnace body, the cooling circulation pipeline section 10 is embedded into a branch inside the furnace bottom electrode 7, and the cooling circulation pipeline section 10 is connected with the conducting strip 8.
The upper end of the conducting strip 8 and a molten pool form a discharge area, the graphite electrode 1 and the furnace bottom electrode 7 are connected above a molten pool slag limit 15 in the furnace body to generate electric arcs to smelt metal in the furnace body, and the smelted metal flows out through the taphole 13. The furnace bottom electrode 7 is connected with the anode lead wiring terminal 2 through the anode lead segment 3, the conducting strip 8 is used for point reaching control of the furnace bottom electrode 7, and the cooling circulating pipeline segment 10 is in contact connection with the furnace bottom electrode 7 to cool the furnace bottom electrode 7. The refractory bricks 14 play a role in heat preservation and insulation for the furnace body.
According to the utility model discloses a still another embodiment, still include anode lead wire guard shield 4, anode lead wire section 3 outside is equipped with anode lead wire guard shield 4, and anode lead wire guard shield 4 is inside to be filled with graphite refractory material.
An anode lead shield 4 is arranged outside the anode lead segment 3, and graphite refractory material is filled in the anode lead shield 4 to realize heat insulation and anti-leakage protection. When a small amount of molten bath in the furnace seeps out from the periphery of the furnace bottom electrode 7, the molten bath in the furnace can not seep out all the time due to the obstruction of the pressure of the anode lead shield 4 and the graphite refractory material.
According to another embodiment of the present invention, the anode lead shield 4 is welded and sealed with the sealing steel plate 6 at the furnace body contact position.
The contact portion between the shield and the furnace body is sealed with the seal steel plate 6, and the molten bath melt is leaked from the periphery of the furnace bottom electrode 7, and the seal steel plate 6 is not leaked.
According to another embodiment of the present invention, the anode lead shield 4 is higher than the slag limit 15 of the furnace.
The slag limit 15 of the smelting pool refers to the total height of the smelting pool and slag in the furnace, and the total height of the slag limit 15 of the smelting pool in the furnace in normal production is not higher than the height of the shield of the anode lead segment 3.
According to the utility model discloses a still another embodiment, cooling circulation pipeline section 10 is equipped with cooling circulation pipeline import 5 and cooling circulation pipeline export 12, cooling circulation pipeline import 5, cooling circulation pipeline export 12 are worn out respectively from the furnace body and are located the furnace body both sides.
According to another embodiment of the present invention, the cooling circulation pipe segment 10 is externally provided with a cooling circulation pipe shield 11, and the cooling circulation pipe shield 11 is internally filled with graphite refractory material.
According to another embodiment of the present invention, the fluid in the cooling circulation pipe section 10 is water-cooled or air-cooled.
A large amount of heat can be generated in the working process of the furnace bottom electrode 7, and the temperature is reduced through a cooling circulating pipeline. The cooled fluid is water-cooled or air-cooled, enters through the inlet 5 of the cooling circulation pipeline and flows out from the outlet 12 of the cooling circulation pipeline, and is in contact connection with the furnace bottom electrode 7 during the process, so that the furnace bottom electrode 7 is cooled.
The cooling circulation pipeline section 10 is also provided with a cooling circulation pipe shield 11 outside, and the cooling circulation pipe shield 11 is filled with graphite refractory material inside to realize heat insulation and anti-leakage protection. When a small amount of molten bath in the furnace seeps out from the periphery of the furnace bottom electrode 7, the molten bath in the furnace can not seep out all the time due to the separation of the pressure of the cooling circulating pipe shield 11 and the graphite refractory material.
According to another embodiment of the present invention, the anode lead terminal 2 and the furnace body form a "U" structure, as shown in fig. 2.
The anode lead wiring terminal 2 and the furnace body form an L-shaped structure as shown in figure 3.
The anode lead wiring terminal 2 and the furnace body form a T-shaped structure as shown in figure 4.
The anode lead wiring terminal 2 and the furnace body form a convex structure as shown in figure 5.
According to the conditions of different furnace bodies, a proper structure can be adopted in due time so as to achieve the purpose of leakage prevention.
Wherein, the furnace bottom electrode 7 is cast by alloy materials, and the anode lead wiring terminal 2 is made of red copper. The material of the cooling circulation pipeline section 10 is high temperature resistant alloy or red copper. The cooling circulation pipe shield 11 is made of steel and graphite heat-insulating materials.
The utility model discloses a take bottom electrode direct current electric arc furnace's antiseep furnace body structure can stop and take bottom electrode direct current electric arc furnace bottom and the outside seepage of 7 lead wire sections of bottom electrode, tolerates the electromagnetic impact of higher smelting temperature and smelts the ability, so this is the whole stove shape structure of taking bottom electrode direct current electric arc furnace antiseep of permanent type. Furthermore, the utility model has the characteristics of simple design, the preparation is convenient, low in manufacturing cost, antiseep effect safe and reliable etc. The operation is safe and stable in the smelting process, the bottom of the furnace body and the lead of the anode lead wiring terminal 2 of the furnace bottom electrode 7 are well sealed without leakage, and the working state and the cooling effect of the furnace bottom electrode 7 both meet the design requirements. Can completely meet the requirements of high smelting temperature and no leakage of the direct current electric arc furnace and can realize the technical effect of the smelting process of the direct current electric arc furnace.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that are not thought of through the creative work should be covered within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope defined by the claims.
Claims (8)
1. The utility model provides a take antiseep furnace body structure of stove bottom electrode direct current electric arc furnace, includes furnace body, molten bath sediment limit (15), graphite electrode (1) and stove bottom electrode (7), stove bottom electrode (7) constitute inside branch road, and graphite electrode (1) and stove bottom electrode (7) are connected the molten bath sediment limit (15) top in the furnace body and are produced electric arc and smelt its characterized in that to the material in the furnace body: the furnace bottom electrode is characterized by further comprising a furnace bottom shell (9), refractory bricks (14), an iron outlet (13), an anode lead wiring terminal (2), an anode lead segment (3), a conducting strip (8) and a cooling circulating pipeline segment (10), wherein the furnace bottom shell (9) is the bottom of the furnace body, the furnace bottom electrode (7) is connected and installed on the furnace bottom shell (9), the conducting strip (8) is installed at the upper end of the furnace bottom electrode (7), and the conducting strip (8) is communicated with a molten pool in the furnace body; the furnace body is built by refractory bricks (14), and is also provided with an iron outlet (13); the anode lead wiring terminal (2) is connected with the furnace bottom electrode (7) through an anode lead section (3); the cooling circulation pipeline section (10) is arranged at the bottom of the furnace body, the cooling circulation pipeline section (10) is embedded into a branch inside the furnace bottom electrode (7), and the cooling circulation pipeline section (10) is connected with the conducting strip (8).
2. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 1, which is characterized in that: the anode lead wire is characterized by further comprising an anode lead wire shield (4), wherein the anode lead wire shield (4) is arranged outside the anode lead wire section (3), and graphite refractory materials are filled in the anode lead wire shield (4).
3. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 2, which is characterized in that: and the contact part of the anode lead shield (4) and the furnace body is welded and sealed by a sealing steel plate (6).
4. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 2, which is characterized in that: the height of the anode lead wire shield (4) is higher than the slag limit (15) of the molten pool in the furnace body.
5. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 1, which is characterized in that: the cooling circulation pipeline section (10) is provided with a cooling circulation pipeline inlet (5) and a cooling circulation pipeline outlet (12), and the cooling circulation pipeline inlet (5) and the cooling circulation pipeline outlet (12) penetrate out of the furnace body and are arranged on two sides of the furnace body respectively.
6. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 1, which is characterized in that: and a cooling circulation pipe shield (11) is arranged outside the cooling circulation pipeline section (10), and graphite refractory materials are filled in the cooling circulation pipe shield (11).
7. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 1, which is characterized in that: and the fluid in the cooling circulation pipeline section (10) is water-cooled or air-cooled.
8. The leakage-proof furnace body structure of the DC electric arc furnace with the bottom electrode of claim 1, which is characterized in that: the anode lead wiring terminal (2) and the furnace body form a U-shaped structure; or the anode lead wiring terminal (2) and the furnace body form an L-shaped structure; or the anode lead wiring terminal (2) and the furnace body form a T-shaped structure; or the anode lead wiring terminal (2) and the furnace body form a convex structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202023012973.7U CN214250524U (en) | 2020-12-15 | 2020-12-15 | Anti-leakage furnace body structure of direct current electric arc furnace with furnace bottom electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202023012973.7U CN214250524U (en) | 2020-12-15 | 2020-12-15 | Anti-leakage furnace body structure of direct current electric arc furnace with furnace bottom electrode |
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| CN214250524U true CN214250524U (en) | 2021-09-21 |
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| CN202023012973.7U Active CN214250524U (en) | 2020-12-15 | 2020-12-15 | Anti-leakage furnace body structure of direct current electric arc furnace with furnace bottom electrode |
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| CN (1) | CN214250524U (en) |
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