A casting method of cathode structure phosphor cast iron and a cathode structure

Abstract

The present invention discloses a casting method for phosphorus cast iron of a cathode structure and the cathode structure, belonging to the technical field of preparation of electrolytic aluminum cathodes. The casting method comprises the following steps: Step 1: A plurality of brackets are sequentially arranged at intervals along the length direction of the cathode carbon block in the dovetail groove penetrating through the cathode carbon block; Step 2: Two steel bars are placed on the brackets, and the two steel bars are arranged at intervals and located in the dovetail groove, so that the brackets, the groove walls of the dovetail groove of the cathode carbon block and the steel bars enclose a plurality of spaces to be cast, and each steel bar corresponds to at least two spaces to be cast; Step 3: Phosphorus cast iron is sequentially cast into the plurality of spaces to be cast, and the casting time interval between two adjacent spaces to be cast is ≥ 24 h. The casting method for phosphorus cast iron of the cathode structure provided by the present invention does not require preheating, thus reducing energy consumption, and there will be no oxidation phenomenon of the cathode carbon block and the cathode steel bar, reducing the voltage drop and improving the casting success rate.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of cathodes for electrolytic aluminum, and particularly relates to a casting method of phosphorus cast iron for a cathode structure and a cathode structure. Background Art

[0002] In recent years, the graphitized cathode phosphorus cast iron casting technology has been widely used in the domestic aluminum electrolysis industry. The bottom voltage drop is generally controlled at about 200 mV and can be maintained within this range for a long time, which plays a positive role in promoting energy conservation and consumption reduction in aluminum electrolysis.

[0003] The cathode structure includes a cathode carbon block, steel bars, and phosphorus cast iron connecting the carbon block and the steel bars. Currently, the graphitized cathode carbon block phosphorus cast iron casting technology usually first assembles the cathode carbon block and the cathode steel bars to form a cathode group, and then preheats the entire cathode group to 500 - 600 °C, and then casts the molten phosphorus cast iron to achieve the assembly purpose of the cathode.

[0004] This traditional casting method requires a large amount of energy for preheating, and there are also risks such as natural gas explosion and fire; at the same time, the cathode structure formed by this preheating method has a large voltage drop during industrial application. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a casting method of phosphorus cast iron for a cathode structure and a cathode structure.

[0006] The technical solution of the present invention is as follows:

[0007] On the one hand, the present invention provides a casting method of phosphorus cast iron for a cathode structure, including the following steps:

[0008] Step 1: Arrange a plurality of brackets at intervals along the length direction of the cathode carbon block in the dovetail groove penetrating through the cathode carbon block;

[0009] Step 2: Place two steel bars on the brackets. The two steel bars are arranged at intervals and are located in the dovetail groove, so that the brackets, the dovetail groove wall of the cathode carbon block, and the steel bars enclose a plurality of spaces to be cast. Each steel bar corresponds to at least two spaces to be cast;

[0010] Step 3: Cast the phosphorus cast iron into the plurality of spaces to be cast in sequence. The casting time interval between two adjacent spaces to be cast is ≥ 24 h.

[0011] In some embodiments, in Step 3, when the phosphorus cast iron in the previous space to be cast cools to 200 - 300 °C, then cast the next space to be cast.

[0012] In some embodiments, in Step 3, the cooling rate of the phosphorus cast iron is 40 - 50 °C / h.

[0013] In some embodiments, the end portions of the two steel bars away from each other extend out of the dovetail groove. Among the multiple spaces to be cast, the length of the casting space closest to the outermost side of the cathode carbon block is the shortest.

[0014] In some embodiments, the length of the space to be cast closest to the outermost side of the cathode carbon block is 200 - 600 mm.

[0015] In some embodiments, the distance between the outermost bracket and the end face of the cathode carbon block is 50 - 100 mm.

[0016] In some embodiments, when there are at least 3 spaces to be cast corresponding to each steel bar, the casting sequence in step 3 is: first the middle and then the two ends, or first the two ends and then the middle.

[0017] In some embodiments, the material of the bracket is the same as that of the cathode carbon block.

[0018] In some embodiments, in step 1, the cathode carbon block is located in an anti-expansion structure, and the anti-expansion structure includes an anti-expansion cavity with an opening, and the cathode carbon block is located in the anti-expansion cavity.

[0019] In a second aspect, an embodiment of the present invention further provides a cathode structure obtained by using the aforementioned method for casting phosphor cast iron of the cathode structure.

[0020] The beneficial effects of the present invention at least include:

[0021] The method for casting phosphor cast iron of a cathode structure provided by the present invention includes the following steps: Step 1: Arrange a plurality of brackets at intervals along the length direction of the cathode carbon block in the through dovetail groove of the cathode carbon block; Step 2: Place two steel bars on the brackets, and the two steel bars are arranged at intervals and located in the dovetail groove, so that the brackets, the groove walls of the dovetail groove of the cathode carbon block, and the steel bars enclose a plurality of spaces to be cast, and each steel bar corresponds to at least two spaces to be cast; Step 3: Cast phosphor cast iron into the plurality of spaces to be cast in sequence, and the casting time interval between two adjacent spaces to be cast is ≥ 24 h. The method for casting phosphor cast iron of the cathode structure provided by the embodiment of the present invention uses normal temperature casting of phosphor cast iron to replace the technology of preheating and then casting phosphor cast iron in the prior art. Since preheating is not required, energy consumption is reduced, there are no safety hazards of natural gas explosion and fire, and the phenomenon of oxidation of the cathode carbon block and the cathode steel bar will not occur, reducing the voltage drop; this casting method divides the casting area into multiple parts, casts them in sequence and controls the time interval, reducing the risk of cracking of the cathode carbon block during the casting process and improving the casting success rate. The casting success rate of the casting method provided by the present invention is 96.5 - 97.5%, with a high success rate. When applied industrially, the cathode voltage drop is 196 - 197 V, the cathode voltage drop is low, and the energy consumption is low. Brief Description of the Drawings

[0022] Figure 1 It shows a schematic structural diagram during the casting of a cathode structure according to an embodiment of the present invention;

[0023] Figure 2 is Figure 1 a top view of the cathode structure during casting.

[0024] Figure 3 It shows a top view of another cathode structure during casting.

[0025] Description of the Reference Numerals:

[0026] 100 - steel bar; 200 - cathode carbon block; 300 - support; 510 - bottom plate, 520 - side plate, 530 - rib plate; 600 - paste; 700 - ferrophosphorus; 800 - insulation layer. Detailed Embodiments

[0027] In order to enable those skilled in the art in the technical field to which the present application belongs to more clearly understand the present application, the technical solution of the present application will be described in detail below with reference to the drawings through specific embodiments.

[0028] In the related art, the cathode carbon block and the steel bar are preheated as a whole cathode group and then cast. On the one hand, the energy consumption is large and the cost is high. On the other hand, during the preheating process of the cathode group, it will contact with air, causing oxidation of the cathode carbon block and the cathode steel bar to varying degrees, and the oxide layer will increase the cathode voltage drop during the industrial application of the cathode structure.

[0029] To solve the above technical problems, the present invention provides a casting method for ferrophosphorus of a cathode structure and a cathode structure, which reduces energy waste to at least a certain extent and reduces the cathode voltage drop.

[0030] In the first aspect, an embodiment of the present invention provides a casting method for ferrophosphorus of a cathode structure, including the following steps:

[0031] Step 1: Arrange a plurality of supports at intervals along the length direction of the cathode carbon block in the through - set dovetail grooves of the cathode carbon block;

[0032] Please refer to Figure 1 and Figure 2 . Generally speaking, the cathode carbon block 200 is provided with a plurality of dovetail grooves, for example, two. The dovetail grooves are through - set, and the plurality of dovetail grooves are arranged at intervals along the width direction of the cathode carbon block 200. The dovetail grooves are used to install the steel bar 100, and the current flow direction is cathode carbon block 200 - steel bar 100 - bus bar. There are at least six supports 300 in each dovetail groove, at least three supports 300 are in a group, and at least three supports 300 are arranged corresponding to the steel bar 100.

[0033] Step 2: Place two steel bars 100 on the bracket 300. The two steel bars 100 are arranged at intervals and located in the dovetail groove, so that the bracket 300, the dovetail groove wall of the cathode carbon block, and the steel bars 100 enclose a plurality of spaces to be cast. Each steel bar 100 corresponds to at least two spaces to be cast;

[0034] The function of the bracket 300 is to divide the dovetail groove into a plurality of spaces to be cast, that is, a plurality of casting areas, to ensure that the phosphorus cast iron 700 will not leak into other spaces to be cast during casting; at the same time, the bracket 300 also plays a role in supporting and installing the steel bars 100. Each steel bar 100 is placed on at least three corresponding brackets 300. Please refer to Figure 2 , when three brackets 300 are correspondingly arranged for each steel bar 100, each steel bar 100 corresponds to two spaces to be cast; please refer to Figure 3 , when four brackets 300 are correspondingly arranged for each steel bar 100, each steel bar 100 corresponds to three spaces to be cast. Each steel bar 100 can correspond to 2-6 spaces to be cast.

[0035] Step 3: Pour the phosphorus cast iron 700 into the plurality of spaces to be cast in sequence. The casting time interval between two adjacent spaces to be cast is ≥ 24 h. Casting in multiple spaces to be cast can allow heat to be conducted out through the steel bars 100, preventing local overheating and thermal expansion of the steel bars 100 from cracking the cathode carbon block 200; at the same time, it can also release the stress and deformation of the cathode carbon block 200 caused by the thermal expansion and contraction after the casting of the phosphorus cast iron 700, thus avoiding the cracking problem of the cathode carbon block 200; if the casting time interval is too short, it may cause the cracking of the cathode carbon block 200.

[0036] In some embodiments, in Step 3, when the phosphorus cast iron 700 in the previous space to be cast cools to 200 - 300 °C, then pour the phosphorus cast iron 700 into the next space to be cast. Pouring the phosphorus cast iron 700 into the next space to be cast when the cooling temperature is too high may cause local stress in the cathode carbon block 200 to be too high and crack. If the cooling temperature is too low, it will affect the casting efficiency.

[0037] In some embodiments, in Step 3, the cooling rate of the phosphorus cast iron 700 is 40 - 50 °C / h. Controlling a lower cooling rate can slowly release the stress and avoid cracks in the cathode carbon block 200 during the cooling process; if the cooling rate is too fast, the cathode carbon block 200 will crack to a certain extent; if the cooling rate is too slow, the production efficiency will be reduced to a certain extent. In the present application, in order to control the cooling rate of the phosphorus cast iron 700, a heat preservation cover plate can be covered above the cast area. The heat preservation cover plate can be made of asbestos board or nano heat insulation material.

[0038] In some embodiments, the end portions of the two steel bars 100 that are away from each other extend out of the dovetail groove. Among the multiple casting spaces to be cast, the length of the casting space closest to the outermost side of the cathode carbon block 200 is the shortest. The end portion of the cathode carbon block 200 has relatively low strength. Controlling the shortest length of the casting space on the outermost side of the cathode carbon block 200 can well protect the end portion of the carbon block 200 and reduce the risk of cracking.

[0039] Specifically, in some embodiments, the length of the casting space to be cast closest to the outermost side of the cathode carbon block 200 can be 200 - 600 mm.

[0040] In some embodiments, the distance between the outermost bracket 300 and the end face of the cathode carbon block 200 is 50 - 100 mm. By reserving no phosphor cast iron 700 at this position, the risk of cracking at the end of the cathode carbon block 200 can also be reduced; after casting, ramming paste 600 can be solidified at this reserved position to connect the steel bar 100 and the cathode carbon block 200, and it can also conduct electricity at the same time.

[0041] In some embodiments, when there are at least 3 casting spaces corresponding to each steel bar 100, the casting sequence in step 3 is: first in the middle and then at both ends, or first at both ends and then in the middle; for example, please refer to Figure 3 , along the length direction of the cathode carbon block 200, they are the first casting space, the second casting space, the third casting space, the fourth casting space, the fifth casting space, and the sixth casting space respectively. One steel bar 100 corresponds to the first casting space, the second casting space, and the third casting space, and the other steel bar 100 corresponds to the fourth casting space, the fifth casting space, and the sixth casting space. When casting, for one steel bar 100, the second casting space can be cast first, and then the first casting space and the third casting space; for the other steel bar 100, the fifth casting space can be cast first, and then the fourth casting space and the sixth casting space; in other embodiments, for one steel bar 100, the first casting space and the third casting space can be cast first, and then the second casting space; for the other steel bar 100, the fourth casting space and the sixth casting space can be cast first, and then the fifth casting space. In some other embodiments, for one steel bar 100, the first casting space, the second casting space, and the third casting space can be cast in sequence, and for the other steel bar 100, the fourth casting space, the fifth casting space, and the sixth casting space can be cast in sequence.

[0042] In some embodiments, the material of the support 300 is the same as that of the cathode carbon block 200, that is, the support 300 is made of carbon material. The carbon support 300 can act as a conductor and conduct electricity in the formed cathode structure. The support 300 can be a U-shaped support 300. The external dimensions of the U-shaped support 300 match the inner wall dimensions of the dovetail groove. The support 300 is provided with a through groove, and the steel bar 100 is placed in the through groove. The dimension of the support 300 along the length direction of the dovetail groove is 30 - 80 mm. If the dimension of the support 300 along the length direction of the dovetail groove is too large, it will reduce the dimension of the space to be cast, and to a certain extent, reduce the connection strength between the cathode carbon block 200 and the steel bar 100. If the dimension of the support 300 along the length direction of the dovetail groove is too small, it will, to a certain extent, reduce the support strength of the support 300, and may also cause penetration under the action of high-temperature phosphorus cast iron 700.

[0043] In some embodiments, in step 1, the cathode carbon block 200 is located in the anti-expansion structure. The anti-expansion structure includes an anti-expansion cavity with an opening, and the cathode carbon block 200 is located in the anti-expansion cavity. Specifically, the anti-expansion structure includes a bottom plate 510 and two side plates 520. The two side plates 520 are oppositely arranged along the width direction of the cathode carbon block 200. The two side plates 520 are connected to the top of the bottom plate 510. The bottom plate 510 and the two side plates 520 enclose the anti-expansion cavity. During use, the two side plates 520 respectively correspond to the two side surfaces of the cathode carbon block 200 in the width direction. The dovetail groove of the cathode carbon block 200 faces upward, and the side surface of the cathode carbon block 200 opposite to the dovetail groove abuts against the bottom plate 510. In some embodiments, the height of the anti-expansion cavity is higher than the height of the cathode carbon block 200. The dimension of the anti-expansion cavity along the width direction of the cathode carbon block 200 is 100 - 200 mm larger than the width of the cathode carbon block 200. A heat-insulating layer 800 is provided between the side plate 520 and the cathode carbon block 200. The heat-insulating layer 800 can be made of asbestos board, nano heat-insulating material, etc. The setting of the heat-insulating layer 800 can reduce the cooling rate of the phosphorus cast iron 700 molten iron and the cathode carbon block 200, and avoid cracks in the cathode carbon block 200 during the cooling process.

[0044] In some embodiments, in order to improve the connection strength between the side plate 520 and the bottom plate 510, the anti-expansion structure further includes a plurality of rib plates 530. The rib plates 530 are connected to the bottom plate 510 and the side plate 520. The rib plates 530 are located outside the anti-expansion cavity, and each side plate 520 is connected with rib plates 530. Specifically, each side plate 520 is connected with two, three or other numbers of rib plates 530, and the rib plates 530 are arranged at intervals along the length direction of the cathode carbon block 200.

[0045] Based on the same technical concept as the first aspect, in the second aspect, the embodiments of the present invention further provide a cathode structure obtained by using the casting method of phosphorus cast iron for the cathode structure of the first aspect.

[0046] Please refer to Figures 1 to 3 In the cathode structure provided by the embodiment of the present invention, it includes a cathode carbon block 200, steel bars 100, a bracket 300, and phosphorus cast iron 700. The cathode carbon block 200 is provided with dovetail grooves penetrating along the length direction. There are multiple dovetail grooves, and the multiple dovetail grooves are arranged at intervals in the width direction of the cathode carbon block. Each dovetail groove corresponds to at least six brackets 300, and at least six brackets 300 are arranged at intervals along the length direction of the dovetail groove. Each dovetail groove corresponds to two steel bars 100. The two steel bars 100 contact at least three brackets 300 and are both located in the dovetail groove. The two steel bars 100 located in the same dovetail groove extend along the length direction of the cathode carbon block 200. The two steel bars 100 are arranged at intervals, and the adjacent ends of the two steel bars 100 are located between two adjacent brackets 300. Phosphorus cast iron 700 is filled between the steel bars 100, the brackets 300, and the groove wall of the dovetail groove.

[0047] Next, the casting method of the phosphorus cast iron of the cathode structure provided by the embodiment of the present invention will be further described in combination with specific embodiments.

[0048] Example 1

[0049] Embodiment 1 provides a casting method for the phosphorus cast iron of the cathode structure. The cathode carbon block 200 is provided with two dovetail grooves that penetrate along the length direction of the cathode carbon block 200. The casting method includes the following steps:

[0050] 1. Place the cathode carbon block 200 into the anti-expansion cavity of the anti-expansion structure with the dovetail groove of the cathode carbon block 200 facing upward. A 50-mm thick heat-insulating layer 800 is arranged between the cathode carbon block 200 and the side plate 520. Six brackets 300 are sequentially placed at intervals along the length direction of the cathode carbon block 200 in each dovetail groove of the cathode carbon block 200. Four steel bars 100 are hoisted onto the brackets 300. Two steel bars 100 are placed in each dovetail groove, and there is a spacing of 200 mm between the two steel bars 100. Each dovetail groove is divided into four unequal casting spaces. The dimensions of the four casting spaces along the length direction of the cathode carbon block 200 are 600 mm, 1200 mm, 1200 mm, and 600 mm respectively. The distances between the outermost two brackets 300 and the end faces in the length direction of the cathode carbon block 200 are both 100 mm. The distance between the two middle brackets 300, that is, the distance between the third bracket 300 and the fourth bracket 300 counted from one end in the length direction of the cathode carbon block 200, is 400 mm.

[0051] 2. First, pour 700 kg of phosphor cast iron molten iron at 1300 °C into two casting spaces with a length of 600 mm. Immediately cover it with a heat preservation cover plate after casting and cool it at a rate of 43 °C / h. When it cools to 240 °C, pour it into two casting spaces with a length of 1200 mm, and then cover it with a heat preservation cover plate and cool it.

[0052] 3. After the temperature of 700 kg of phosphor cast iron in all casting spaces reaches room temperature, use 600 kg of paste to solidify the empty positions.

[0053] Example 2

[0054] Example 2 provides a casting method for the phosphor cast iron of the cathode structure. The cathode carbon block 200 is provided with two dovetail grooves, and the two dovetail grooves penetrate along the length direction of the cathode carbon block 200. The casting method includes the following steps:

[0055] 1. Place the cathode carbon block 200 into the anti-expansion cavity of the anti-expansion structure, with the dovetail grooves of the cathode carbon block 200 facing upwards. A heat preservation layer 800 with a thickness of 50 mm is arranged between the cathode carbon block 200 and the side plate 520. Along the length direction of the cathode carbon block 200, 8 brackets 300 are sequentially and spacedly placed in each dovetail groove of the cathode carbon block 200. Lift four steel bars 100 onto the brackets 300. Two steel bars 100 are placed in each dovetail groove, and there is a spacing of 200 mm between the two steel bars 100. Each steel bar 100 is supported by four brackets 300. Each dovetail groove is divided into 6 unequal casting spaces. The dimensions of the 6 casting spaces along the length direction of the cathode carbon block 200 are 400 mm, 600 mm, 800 mm, 800 mm, 600 mm, and 400 mm respectively. The distances between the two outermost brackets 300 and the end faces of the cathode carbon block 200 in the length direction are both 60 mm. The distance between the two middle brackets 300, that is, the distance between the fourth bracket 300 and the fifth bracket 300 counted from one end of the cathode carbon block 200 in the length direction, is 320 mm.

[0056] 2. First, cast 700 kg of phosphor cast iron into two casting spaces with a length of 600 mm. Immediately cover it with a heat preservation cover plate after casting and cool it at a rate of 48 °C / h. When it cools to 200 °C, cast it into two casting spaces with a length of 400 mm and two casting spaces with a length of 800 mm, and then cover it with a heat preservation cover plate and cool it at a rate of 48 °C / h.

[0057] 3. After the temperature of 700 kg of phosphor cast iron in all areas reaches room temperature, use 600 kg of paste to solidify the empty positions.

[0058] Example 3

[0059] Example 3 is taken as a reference to Example 2. The difference between Example 3 and Example 2 is that in step 2, two spaces to be cast with a length of 800 mm are first cast, and when they are cooled to 200°C, two spaces to be cast with a length of 600 mm are cast, and when they are cooled to 200°C, two spaces to be cast with a length of 400 mm are cast.

[0060] Example 4

[0061] Example 4 is based on Example 2. The difference between Example 4 and Example 2 is that in step 1, the dimensions of the six spaces to be cast along the length direction of the cathode carbon block 200 are 300 mm, 600 mm, 900 mm, 900 mm, 600 mm and 300 mm respectively.

[0062] Example 5

[0063] Example 5 provides a casting method for cathode structure phosphorus pig iron. The cathode carbon block 200 is provided with two dovetail grooves. The two dovetail grooves are provided through the length direction of the cathode carbon block 200. The casting method includes the following steps:

[0064] 1. Place the cathode carbon block 200 into the anti-expansion cavity of the anti-expansion structure, with the dovetail groove of the cathode carbon block 200 facing upwards, and place a 50mm thick insulation layer 800 between the cathode carbon block 200 and the side plate 520; place 6 brackets 300 in each dovetail groove of the cathode carbon block 200 along the length direction of the cathode carbon block 200, and hoist four steel rods 100 onto the brackets 300, with two steel rods 100 placed in each dovetail groove, with a spacing of 200mm between the two steel rods 100, and each steel rod 100 is supported by three brackets 300. 00 support, each dovetail groove is divided into four unequal spaces to be cast, the dimensions of the four spaces to be cast along the length direction of the cathode carbon block 200 are 500mm, 1300mm, 1300mm and 500mm respectively, the distance between the two outermost brackets 300 and the end face of the cathode carbon block 200 in the length direction is 80mm, the distance between the two middle brackets 300 is counted from one end of the cathode carbon block 200 in the length direction, and the distance between the third bracket 300 and the fourth bracket 300 is 360mm.

[0065] 2. First, cast two 700 phosphorus pig irons with a length of 1300mm in the casting space. Immediately after the casting is completed, cover it with an insulation cover and cool it at a rate of 45℃ / h. When it cools to 280℃, cast two more 500mm long casting spaces, and then cover it with an insulation cover and cool it.

[0066] 3. After the temperature of phosphorus pig iron 700 in all areas reaches room temperature, use paste 600 to fix the remaining space.

[0067] Comparative Example 1

[0068] Comparative Example 1 was referenced to Example 2. The difference between Comparative Example 1 and Example 2 was that the anti-expansion structure was not used, and the rest was the same as Example 2.

[0069] Comparative Example 2

[0070] Comparative Example 2 was referenced to Example 2. The difference between Comparative Example 2 and Example 2 was that the bracket 300 was not used, and one-time normal temperature casting was adopted.

[0071] Comparative Example 3

[0072] In Comparative Example 3, the whole cathode carbon block 200 and the steel bar 100 were preheated to 500 °C, and then the phosphorus cast iron 700 was cast at a high temperature at one time.

[0073] Table 1

[0074] Number Success rate / % Pressure drop / V Example 1 96.5 196 Example 2 97 197 Example 3 97.5 197 Example 4 97 196 Example 5 97 196 Comparative Example 1 92 202 Comparative Example 2 81 195 Comparative Example 3 96 210

[0075] The casting methods of the cathode structure phosphorus cast iron provided by Examples 1 to 5 and Comparative Examples 1 to 3 were used for casting, the casting success rate was counted, and the obtained cathode structure was used for aluminum electrolysis production, and the voltage drop data of the cathode structure were collected, as shown in Table 1.

[0076] After casting, the appearance of cracks in the cathode carbon block 200 indicated casting failure, and the appearance of the cathode carbon block 200 being intact without cracks indicated casting success. The success rate in Table 1 referred to the percentage of the number of successful castings in the total number of castings.

[0077] As can be seen from the data in Table 1, for the casting methods provided by Examples 1 to 5 of the present invention, the casting success rate was 96.5 - 97.5%, the success rate was high, the cathode voltage drop was 196 - 197 V during industrial application, the cathode voltage drop was low, and the energy consumption was low.

[0078] For the casting methods provided by Comparative Examples 1 to 2, the casting success rate was 81 - 92%, and the casting success rate was lower than that of Examples 1 to 5 of the present invention; the cathode voltage drop was 195 - 202 V during industrial application, and the cathode voltage drop was at the same level as that of Examples 1 to 5 of the present invention.

[0079] For the casting method provided by Comparative Example 3, the casting success rate was 96%, which was close to that of Examples 1 to 5 of the present invention. The cathode voltage drop was 210 V during industrial application, the cathode voltage drop was higher than that of Examples 1 to 5 of the present invention, and the energy consumption was high.

[0080] The casting method of the phosphorus cast iron for the cathode structure provided by the embodiment of the present invention and the cathode structure adopt the normal-temperature casting of the phosphorus cast iron 7 to replace the technology of preheating and then casting the phosphorus cast iron in the prior art. Since preheating is not required, the energy consumption is reduced, and the phenomenon of oxidation of the cathode carbon block and the cathode steel bar will not occur, reducing the voltage drop. The casting method divides the casting area into multiple parts, casts them in sequence and controls the time interval, reducing the risk of cracking of the cathode carbon block during the casting process, improving the casting success rate, having no safety hazards of natural gas explosion and fire, improving the work efficiency and safety, and reducing the production cost and environmental pollution. For the casting method provided by the present invention, the casting success rate is 96.5-97.5%, with a high success rate. When applied industrially, the cathode voltage drop is 196-197V, the cathode voltage drop is low, and the energy consumption is low.

[0081] Although the preferred embodiments of the present application have been described, those of ordinary skill in the art can make additional changes and modifications to these embodiments once they learn the basic creative concepts. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present application.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

1. A casting method for cathode structure phosphorus cast iron, characterized in that, It includes the following steps: Step 1: Arrange multiple brackets at intervals along the length direction of the cathode carbon block in the through dovetail grooves of the cathode carbon block; Step 2: Place two steel bars on the brackets. The two steel bars are arranged at intervals and located in the dovetail grooves, so that the brackets, the dovetail groove walls of the cathode carbon block, and the steel bars enclose multiple spaces to be cast. Each steel bar corresponds to at least two spaces to be cast; Step 3: Cast phosphor cast iron into the multiple spaces to be cast in sequence. The casting time interval between two adjacent spaces to be cast is ≥24 h; when the phosphor cast iron in the previous space to be cast cools to 200 - 300 °C, then cast the next space to be cast; the cooling rate of the phosphor cast iron is 40 - 50 °C / h.

2. The casting method of the cathode structure phosphor cast iron according to claim 1, characterized in that Both ends of the two steel bars extending away from each other protrude out of the dovetail grooves. Among the multiple spaces to be cast, the length of the casting space closest to the outermost side of the cathode carbon block is the shortest.

3. The casting method of the cathode structure phosphorus cast iron according to claim 2, characterized in that, The length of the space to be cast closest to the outermost side of the cathode carbon block is 200 - 600 mm.

4. The casting method of the cathode structure phosphorus pig iron according to claim 1, characterized in that, The distance between the outermost bracket and the end face of the cathode carbon block is 50 - 100 mm.

5. The casting method of the cathode structure phosphor cast iron according to claim 1, characterized in that, When each steel bar corresponds to at least 3 of the spaces to be cast, the casting order in Step 3 is: first in the middle and then at both ends, or first at both ends and then in the middle.

6. The casting method of the cathode structure phosphor cast iron according to claim 1, characterized in that The material of the bracket is the same as that of the cathode carbon block.

7. The casting method of the cathode structure phosphor cast iron according to claim 1, characterized in that, In Step 1, the cathode carbon block is located in an anti-expansion structure. The anti-expansion structure includes an anti-expansion cavity with an opening, and the cathode carbon block is located in the anti-expansion cavity.

8. A cathode structure, characterized in that, Obtained by using the casting method of the cathode structure phosphor cast iron according to any one of claims 1 - 7.

Images