Calcium carbide furnace electrode cylinder structure optimization method

Abstract

The application provides a calcium carbide furnace electrode cylinder structure optimization method and relates to the technical field of calcium carbide furnace electrode cylinder.The application realizes accurate mixed loading of different width rib plates through stepped positioning grooves, avoids radial misplacement, realizes collinear automatic production of three specifications of blank through the reform of a blanking system, saves equipment investment, improves material flow efficiency, enhances the radial heat transfer and gas flow capacity of the high-temperature area through the transverse rectangular hole and the differential distribution density, increases the heat dissipation area and the electric conduction section in the high-temperature area through mixed configuration of widened rib plates and conventional rib plates, solves the problem that the side rib plate of the existing uniform rib plate structure is easy to overburn and the electric conduction capacity is insufficient, and establishes a low-resistance axial electric conduction path at the upper and lower electrode cylinder connection through the welding structure of the small rib plate connecting the upper and lower widened rib plates, avoiding local overheating and melting accidents caused by traditional end surface contact.

Description

Technical Field

[0001] This invention relates to the field of calcium carbide furnace electrode cylinder technology, specifically a method for optimizing the structure of calcium carbide furnace electrode cylinder. Background Technology

[0002] The calcium carbide furnace is the core thermal equipment for calcium carbide production, and its electrode system plays a crucial role in electrical and heat transfer. The electrode cylinder, serving as the container for the electrode paste and the sintering mold, is a key component of the electrode system. The electrode cylinder is constructed by welding a metal shell, stiffening ribs, and arc plates. The stiffening ribs are arranged circumferentially along the inner wall of the electrode cylinder shell and extend radially towards the center of the electrode cylinder. During furnace operation, the electrode paste fills the interior of the electrode cylinder and gradually sinterstales under high temperature to form a solid electrode with electrical conductivity. The electrode cylinder shell protects the internal electrode paste from oxidation, while the stiffening ribs bear most of the current during sintering, conducting the current from the shell to the center of the electrode. Simultaneously, the stiffening ribs also increase the heat dissipation area and conduct heat. The structural design of the electrode cylinder directly affects the sintering quality, electrical conductivity, and service life of the electrode, thus influencing the load capacity and operational stability of the calcium carbide furnace.

[0003] In existing technologies, the ribs of the electrode cylinder typically adopt a single radial width specification and are uniformly arranged circumferentially on the inner wall of the electrode cylinder shell. This uniformly distributed rib structure presents the following problems in the actual operation of the calcium carbide furnace: due to the significant non-uniformity of the thermal and electric field distribution inside the furnace, the side facing the furnace center (i.e., the inner corner region) experiences the strongest high-temperature radiation and the highest current density. The ribs in this region are under constant high heat load, and the tips are prone to overheating, oxidation, thinning, or even melting. Meanwhile, the ribs facing away from the furnace center have a lower heat load and fail to fully utilize their electrical conductivity and heat dissipation capabilities. This uniform rib distribution method results in both overheating failure of the ribs in the high-temperature zone and redundant capacity of the ribs in the low-temperature zone, limiting the overall current-carrying capacity improvement of the electrode cylinder.

[0004] Therefore, a method for optimizing the structure of the electrode cylinder of a calcium carbide furnace is provided. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention provides the following technical solution: a method for optimizing the structure of an electrode cylinder in a calcium carbide furnace, comprising the following steps: S1: The electrode cylinder assembly plate is processed by cutting inward based on the original groove depth to form a stepped positioning groove with a depth difference, so that the widened stiffener and the conventional stiffener are positioned on the assembly plate with the same outer diameter reference plane. S2: Modify the stiffener blanking system to enable it to simultaneously punch and fold at least three different specifications of steel plates, including conventional stiffener blank specifications, widened stiffener blank specifications, and small stiffener blank specifications. S3: Replace the punching machine mold with a square horizontal hole mold to punch a horizontal rectangular hole on the rib plate. The area of ​​the horizontal rectangular hole is larger than the area of ​​the original C-shaped hole. S4: Use a shearing machine to cut the steel plate of the small stiffener blank into small stiffeners of the preset size; S5: Assemble the stiffeners and arc plates on the assembly plate. Mix conventional stiffeners and widened stiffeners in the same electrode cylinder. The radial width of the widened stiffeners is greater than that of the conventional stiffeners. The widened stiffeners are concentrated in the first arc-shaped area corresponding to the high-temperature zone of the furnace core in the circumference of the electrode cylinder. The conventional stiffeners are arranged in the second arc-shaped area corresponding to other areas in the furnace in the circumference of the electrode cylinder. The first arc-shaped area and the second arc-shaped area together form a complete circumferential distribution. The radial width is calculated from the opening on the inner wall of the electrode cylinder.

[0006] S6: Position the inner corner area within the ring, weld the small stiffener to the bottom of the widened stiffener, and weld the widened stiffener to the inner corner area, so that the upper and lower adjacent electrode cylinders form an enhanced axial conductive path in the inner corner area.

[0007] Furthermore, in S1, the depth of the inward cut is 45mm, and the depth difference of the stepped positioning groove is 45mm.

[0008] Furthermore, in S5, the radial width of the conventional stiffener is 270mm, and the radial width of the widened stiffener is 315mm, an increase of 45mm in radial width; the number of conventional stiffeners is 8 or 10, and the number of widened stiffeners is 6.

[0009] Furthermore, in S3, the length direction of the transverse rectangular hole is parallel to the radial direction of the electrode cylinder shell; the heat-conducting hole distribution density on the widened stiffener is greater than that on the conventional stiffener.

[0010] Furthermore, in S5, the first arc-shaped region extends symmetrically to both sides with the shell position of the electrode cylinder corresponding to the furnace core direction as the central reference point; the widened stiffeners are evenly arranged at equal intervals in the first arc-shaped region, and the conventional stiffeners are evenly arranged at equal intervals in the second arc-shaped region.

[0011] Furthermore, in S2, the three different specifications of steel plates are: conventional stiffening plate blanks with a specification of 330×1498×3mm, widened stiffening plate blanks with a specification of 375×1498×3mm, and small stiffening plate blanks with a specification of 240×1500×3mm; in S4, the preset size of the small stiffening plate is 240×375×3mm.

[0012] Furthermore, prior to S5, the process also includes: placing regular stiffening plate blanks, widened stiffening plate blanks, and small stiffening plate blanks on the stiffening plate loading platform, performing punching and bending processes in sequence, and then hoisting them from the unloading platform to the assembly frame unloading platform.

[0013] Furthermore, before S6, it also includes: welding the sheared small stiffening plate to the bottom of the electrode cylinder, and then using a single beam crane to lift the electrode cylinder to the ring for docking; in S6, the welding specifically includes: using an F wrench to press the small stiffening plate tightly against the stiffening plate of the lower electrode cylinder, and then placing the widened stiffening plate in the inner corner direction before welding and fixing it.

[0014] Furthermore, in S6, the widening stiffeners are concentrated in the inner corner area of ​​the electrode cylinder, and the small stiffeners are welded tightly to the widening stiffeners of the lower electrode cylinder to form an enhanced conductive path in the inner corner area.

[0015] Furthermore, in S6, there is a preset length difference between the bottom end of the widening stiffener and the bottom end of the electrode cylinder shell, so that after the upper and lower adjacent electrode cylinders are connected, an axial flow guide gap is formed between the bottom end of the widening stiffener in the upper electrode cylinder and the top surface of the lower electrode cylinder shell; the axial flow guide gap is used to allow the high temperature gas in the electrode cylinder to flow axially, and at the same time, the widening stiffener is electrically connected to the widening stiffener of the lower electrode cylinder through a small stiffener welded to its bottom end.

[0016] Beneficial effects The present invention has the following beneficial effects: 1. This invention achieves precise mixing of stiffeners of different widths through stepped positioning grooves, avoiding radial misalignment; it enables automated production of three specifications of billets on the same line through modification of the feeding system, saving equipment investment and improving material flow efficiency; it enhances radial heat transfer and gas flow capacity in the high-temperature zone through transverse rectangular holes and differentiated distribution density; it increases the heat dissipation area and conductive cross-section in the high-temperature zone by mixing widened stiffeners with conventional stiffeners, solving the problems of easy overheating and insufficient conductivity of furnace core side stiffeners in existing uniformly distributed stiffener structures; and it establishes a low-resistance axial conductive path at the connection of the upper and lower electrode cylinders through a welded structure of small stiffeners connecting the upper and lower widened stiffeners, avoiding local overheating and melting accidents caused by traditional end-face contact.

[0017] 2. This invention increases the radial width of the widened stiffeners by 45mm, extending the heat dissipation path by approximately 16.7%. This allows for more effective heat transfer to the center of the electrode paste in the high-temperature zone of the furnace core, significantly reducing the risk of overheating at the stiffener tips. The combination of 6 widened stiffeners and 8 conventional stiffeners increases the total effective conductive cross-sectional area of ​​the electrode cylinder. According to the law of resistance, an increased cross-sectional area reduces resistance. Under the same temperature rise control standard, the maximum current carrying capacity of the electrode cylinder can be increased from 95KA to 97KA, corresponding to an increase in the calcium carbide furnace load from 31MW to 33MW, providing electrode hardware support for increased production. The number of conventional stiffeners can be adjusted between 8 and 10 depending on the furnace conditions, improving the applicability and flexibility of the method.

[0018] 3. This invention overcomes the technical bias of the traditional uniform circumferential distribution of electrode cylinder ribs by setting up arc-shaped region division and rib arrangement. The wider ribs with larger radial width are concentrated in the first arc-shaped region where the furnace core has the strongest high temperature effect, realizing targeted reinforcement of this weak link of thermoelectric coupling and solving the problem of furnace core side ribs failing first due to overheating in the traditional uniform distribution structure. The first arc-shaped region is symmetrically expanded with the furnace core direction as the center, ensuring the structural symmetry and heating uniformity of the electrode cylinder in the high temperature zone. Conventional ribs are arranged at equal intervals in the second arc-shaped region, maintaining the overall mechanical stability and circumferential stiffness of the electrode cylinder, while avoiding unnecessary material and weight increases. The asymmetric hybrid configuration allows the electrode cylinder to adapt to the non-uniform thermal field distribution in the calcium carbide furnace and the non-uniform electric field distribution in the calcium carbide furnace, improving the current carrying capacity and extending the service life of the electrode cylinder.

[0019] 4. The axial flow-guiding notch of this invention provides an axial flow channel for the high-temperature volatile gases generated during the electrode paste sintering process, preventing gas from accumulating at the root of the rib plate at the joint of the upper and lower electrode cylinders and forming eddies, thereby preventing localized ablation at the root of the rib plate due to flue gas accumulation; the conductive function and the gas guiding function are structurally separated: the axial current is conducted through the welding path on the side of the small rib plate, without relying on the bottom end face contact of the widened rib plate; the presence of the axial flow-guiding notch does not affect the conductive connection; the functional separation design ensures both the thermal stability and electrical stability of the electrode cylinder under high load operating conditions, solving the problem of localized burn-off caused by poor flue gas emission, ensuring reliable axial current conduction, extending the service life of the electrode cylinder, and improving the safety of the calcium carbide furnace operation.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] Figure 1 This is a side view of the electrode cylinder of the present invention.

[0022] Figure 2 This is a distribution diagram of the conventional stiffening plates and the widened stiffening plates of the present invention.

[0023] Figure 3 This is a side view of the conventional stiffening plate of the present invention.

[0024] Figure 4 This is a side view of the widened stiffener of the present invention.

[0025] In the diagram: Electrode cylinder 1, conventional stiffener 2, widened stiffener 3, small stiffener 4. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figures 1 to 4 The present invention provides a technical solution: a method for optimizing the structure of an electrode cylinder in a calcium carbide furnace, comprising the following steps: S1: The electrode cylinder assembly plate is processed by cutting inward based on the original groove depth to form a stepped positioning groove with a depth difference, so that the widened stiffener 3 and the conventional stiffener 2 are positioned on the assembly plate with the same outer diameter reference plane. S2: Modify the stiffener blanking system to enable it to simultaneously punch and fold at least three different specifications of steel plates, including conventional stiffener blank specifications, widened stiffener blank specifications, and small stiffener blank specifications. S3: Replace the punching machine mold with a square horizontal hole mold to punch a horizontal rectangular hole on the rib plate. The area of ​​the horizontal rectangular hole is larger than the area of ​​the original C-shaped hole. S4: Use a shearing machine to cut the steel plate of the small stiffener blank into small stiffener 4 of the preset size; S5: Assemble the stiffeners and arc plates on the assembly plate. Mix and configure conventional stiffeners 2 and widened stiffeners 3 in the same electrode cylinder 1. The radial width of the widened stiffeners 3 is greater than that of the conventional stiffeners 2. The widened stiffeners 3 are concentrated in the first arc-shaped area of ​​the electrode cylinder 1 corresponding to the high temperature zone of the furnace core. The conventional stiffeners 2 are configured in the second arc-shaped area of ​​the electrode cylinder 1 corresponding to other areas in the furnace. The first arc-shaped area and the second arc-shaped area together form a complete circumferential distribution. S6: Position the inner corner area within the ring, weld the small stiffener 4 to the bottom of the widened stiffener 3, and weld the widened stiffener 3 to the inner corner area, so that the upper and lower adjacent electrode cylinders 1 form an enhanced axial conductive path in the inner corner area.

[0028] In specific implementation, step S1 is executed first. The original electrode cylinder assembly plate has a uniform depth of positioning groove, which only fits a single radial width rib. Using a cutting device, material is removed radially inward along the electrode cylinder assembly plate to a depth of 45mm, forming a stepped positioning groove with a depth difference of 45mm. The stepped positioning groove includes a first positioning surface and a second positioning surface, which correspond to the positioning positions of the widened rib 3 and the conventional rib 2, respectively. The two positioning surfaces differ radially by 45mm but share the same outer diameter reference surface, which is the cylindrical surface of the inner wall of the electrode cylinder 1 shell.

[0029] Next, proceed to step S2. The stiffener plate unloading system includes a loading suction cup, a unloading suction cup, a material fixing device, and a conveying line. Adjusting the suction cup position, adding a fixing device, and modifying the control program enable the system to process three specifications of steel plate blanks: conventional stiffener plate blanks (330mm×1498mm×3mm), widened stiffener plate blanks (375mm×1498mm×3mm), and small stiffener plate blanks (240mm×1500mm×3mm). The conventional and widened stiffener plate blanks have bending areas of 10mm and 20mm respectively at both ends along the width direction, forming a folded edge structure welded to the electrode cylinder 1 shell after bending.

[0030] Then proceed to step S3. Remove the original C-shaped hole mold and install a square transverse hole mold. The length direction of the punch is consistent with the width direction of the rib plate, so that the length direction of the transverse rectangular hole formed by stamping is parallel to the radial direction of the electrode cylinder 1 shell, and the area of ​​a single hole is larger than the area of ​​the original C-shaped hole.

[0031] Next, proceed to step S4. The small stiffener blank 240mm×1500mm×3mm processed in step S2 is fed into the shearing machine and cut to a length of 375mm to obtain a small stiffener 4 with dimensions of 240mm×375mm×3mm.

[0032] Then, step S5 is executed. On the modified electrode cylinder assembly plate, the widened stiffener 3 is placed on the first positioning surface, and the conventional stiffener 2 is placed on the second positioning surface, with the outer edges of both abutting the same outer diameter reference surface. A single electrode cylinder 1 is configured with a combination of widened stiffener 3 with a radial width of 315mm and conventional stiffener 2 with a radial width of 270mm. The widened stiffener 3 is concentrated in the first arc-shaped area, and the conventional stiffener 2 is arranged in the second arc-shaped area, with the two areas forming a complete circumference. After the stiffeners are placed, the arc plate is welded to the inner edge of the stiffener to form the electrode cylinder 1.

[0033] Finally, proceed to step S6. Before hoisting, weld the small stiffening plate 4 to the inner side of the lower cylinder wall of the electrode cylinder 1, corresponding to the bottom end of the widening stiffening plate 3. Use a single-beam crane to hoist the electrode cylinder 1 into the ring, axially align it with the lower electrode cylinder 1, and perform positioning in the inner corner area to align the upper and lower widening stiffening plates 3 circumferentially. Use an F-wrench to press the side of the small stiffening plate 4 tightly against the side of the lower widening stiffening plate 3 before welding, forming a reinforced axial conductive path connecting the upper and lower widening stiffening plates 3 with the small stiffening plate 4.

[0034] The stepped positioning grooves enabled precise mixing of stiffeners of different widths, avoiding radial misalignment. The modification of the feeding system enabled the automated production of three specifications of billets on the same line, saving equipment investment and improving material flow efficiency. The transverse rectangular holes and differentiated distribution density enhanced the radial heat transfer and gas flow capacity in the high-temperature zone. By mixing and configuring the widened stiffeners 3 with the conventional stiffeners 2, the heat dissipation area and conductive cross-section in the high-temperature zone were concentrated to increase, solving the problems of easy overheating and insufficient conductivity of the furnace core side stiffeners in the existing uniformly distributed stiffener structure. The welded structure connecting the upper and lower widened stiffeners 3 with small stiffeners 4 established a low-resistance axial conductive path at the connection of the upper and lower electrode cylinders 1, avoiding local overheating and melting accidents caused by traditional end-face contact.

[0035] Furthermore, in S1, the depth of the inward cut is 45mm, and the depth difference of the stepped positioning groove is 45mm.

[0036] In practice, the electrode cylinder assembly plate is fixed to a milling machine or wire cutting equipment and aligned with the central axis as a reference. The circumferential radius of the bottom of the original positioning groove is measured, a cutting line offset radially inward by 45mm is marked, and material is removed. After removal, a first positioning area and a second positioning area with a radii differing by 45mm are formed, respectively accommodating the widened stiffener 3 and the conventional stiffener 2. During assembly, the widened stiffener 3 is embedded in the first positioning area, and the conventional stiffener 2 is embedded in the second positioning area, with both outer surfaces in contact with the same outer diameter reference surface. Thus, the widened stiffener 3 extends 45mm further towards the center of the electrode cylinder 1 than the conventional stiffener 2, ensuring accurate radial positioning.

[0037] The stepped positioning groove design solves the problem that traditional assembly trays cannot accurately position two different radial width stiffeners simultaneously. By making the widened stiffener 3 and the conventional stiffener 2 share the same outer diameter reference plane, the consistency of the inner diameter of the electrode cylinder 1 is ensured, and the outer edge of the stiffener is tightly fitted to the cylinder wall. This provides a reliable tooling foundation for subsequent mixed configuration of stiffeners and avoids uneven welding gaps or deviations in the inner diameter of the electrode cylinder caused by radial misalignment of the stiffeners.

[0038] Furthermore, in S5, the radial width of the conventional stiffening plate 2 is 270mm, and the radial width of the widened stiffening plate 3 is 315mm, with the radial width increased by 45mm; the number of conventional stiffening plates 2 is 8 or 10, and the number of widened stiffening plates 3 is 6.

[0039] In practical implementation, taking electrode cylinder 1 of a 40500KVA calcium carbide furnace as an example, a single electrode cylinder 1 is equipped with 8 conventional stiffeners 2 and 6 widened stiffeners 3, totaling 14 stiffeners. The radial width of the conventional stiffeners 2 is 270mm, and the radial width of the widened stiffeners 3 is 315mm, which is 45mm wider. During assembly, the inner edge of the widened stiffeners 3 extends 45mm further towards the center than the inner edge of the conventional stiffeners 2, increasing the contact area with the electrode paste and increasing the heat dissipation path. In another implementation scenario, 10 conventional stiffeners 2 can be configured, while the number of widened stiffeners 3 remains 6, with the dimensional relationship unchanged.

[0040] The radial width of the widened stiffener 3 is increased by 45mm, which extends its heat dissipation path by about 16.7%. This allows for more effective heat transfer to the center of the electrode paste in the high-temperature zone of the furnace core, significantly reducing the risk of overheating at the stiffener tip. The combination of 6 widened stiffeners 3 and 8 conventional stiffeners 2 increases the total effective conductive cross-sectional area of ​​the electrode cylinder 1. According to the law of resistance, an increase in cross-sectional area reduces resistance. Under the same temperature rise control standard, the maximum current carrying capacity of the electrode cylinder 1 can be increased from 95KA to 97KA, corresponding to an increase in the calcium carbide furnace load from 31MW to 33MW, providing electrode hardware support for increased production. The number of conventional stiffeners 2 can be adjusted between 8 and 10 depending on the furnace conditions, improving the applicability and flexibility of the method.

[0041] Furthermore, in S3, the length direction of the transverse rectangular hole is parallel to the radial direction of the electrode cylinder 1 shell; the heat-conducting hole distribution density on the widened stiffener 3 is greater than the heat-conducting hole distribution density on the conventional stiffener 2.

[0042] In practical implementation, the length direction of the punch in the punching die is consistent with the width direction of the rib plate, and after punching, the length direction of the transverse rectangular hole is parallel to the radial direction of the electrode cylinder 1 shell. The spacing of the heat-conducting holes on the widened rib plate 3 in both the length and width directions is smaller than that of the conventional rib plate 2, that is, the heat-conducting hole distribution density of the widened rib plate 3 is greater than that of the conventional rib plate 2. The transverse rectangular holes are arranged radially, and the heat and sintering gas in the furnace can be conducted and escaped radially along the length direction of the holes. The widened rib plate 3 is located in the high-temperature zone and has a greater distribution density, which enhances the heat transfer and gas flow capacity in this area; the conventional rib plate 2 is located in the lower heat load area, and its distribution density is correspondingly reduced.

[0043] The transverse rectangular holes are arranged radially along their length, forming a directional heat transfer channel from the outside of the electrode cylinder 1 shell to the central electrode paste area. This aligns with the escape direction of volatile gases generated during electrode paste sintering, promoting efficient heat and gas exchange. The higher density of heat-conducting holes on the widened stiffener 3 specifically enhances the heat dissipation capacity of the high-temperature zone in the furnace core, helping to reduce local temperature peaks in this area and preventing oxidation and burn-off of the stiffener material due to excessive temperature, as well as poor local sintering of the electrode paste due to excessive temperature. The lower density of heat-conducting holes on the conventional stiffener 2 ensures the structural strength of the electrode cylinder 1 in non-high-temperature areas. Furthermore, the single-hole area of ​​the transverse rectangular holes is larger than that of the original C-shaped holes, and the increased opening ratio reduces the self-weight of the stiffeners, thereby reducing the mechanical load on the electrode lifting hydraulic system during the electrode lifting process of the 40500KVA calcium carbide furnace.

[0044] Furthermore, in S5, the first arc-shaped region extends symmetrically to both sides with the shell position of the electrode cylinder 1 corresponding to the furnace core direction as the central reference point; the widened stiffeners 3 are evenly arranged at equal intervals in the first arc-shaped region, and the conventional stiffeners 2 are evenly arranged at equal intervals in the second arc-shaped region.

[0045] In practical implementation, the outer shell generatrix of electrode cylinder 1 facing the furnace core is used as the central reference point, and approximately 77 degrees of central angle are measured to both sides to define the first arc-shaped region (totaling approximately 154 degrees). This region directly faces the high-temperature radiation zone of the furnace core. Six widened stiffening plates 3 are arranged at equal intervals within the first arc-shaped region. The remaining approximately 206-degree range constitutes the second arc-shaped region, where eight or ten conventional stiffening plates 2 are arranged at equal intervals. The widened stiffening plates 3 are concentrated in the high-temperature zone to enhance heat dissipation and conductivity, while the conventional stiffening plates 2 are evenly distributed in the remaining areas to ensure structural symmetry and stability.

[0046] The arc-shaped region division and stiffener arrangement method breaks through the technical bias of the traditional uniform circumferential distribution of electrode cylinder stiffeners. The widened stiffeners 3 with a larger radial width are concentrated in the first arc-shaped region where the furnace core temperature is strongest, realizing targeted reinforcement of this weak link of thermoelectric coupling and solving the problem of furnace core side stiffeners failing first due to overheating in the traditional uniform distribution structure. The first arc-shaped region is symmetrically expanded with the furnace core direction as the center, ensuring the structural symmetry and heating uniformity of electrode cylinder 1 in the high-temperature zone. Conventional stiffeners 2 are arranged at equal intervals in the second arc-shaped region, maintaining the overall mechanical stability and circumferential stiffness of electrode cylinder 1, while avoiding unnecessary material and weight increases. The asymmetric hybrid configuration allows electrode cylinder 1 to adapt to the non-uniform thermal field distribution in the calcium carbide furnace and the non-uniform electric field distribution in the calcium carbide furnace, improving the current carrying capacity and extending the service life of electrode cylinder 1.

[0047] Furthermore, in S2, the three different specifications of steel plates are: conventional stiffening plate blanks with a specification of 330×1498×3mm, widened stiffening plate blanks with a specification of 375×1498×3mm, and small stiffening plate blanks with a specification of 240×1500×3mm; in S4, the preset size of the small stiffening plate 4 is 240×375×3mm.

[0048] In specific implementation, the dimensions of the three types of steel plate blanks are clearly defined: the conventional rib plate blank is 330mm wide, 1498mm long, and 3mm thick, with 10mm and 20mm bending areas at both ends along the width direction; the widened rib plate blank is 375mm wide, 1498mm long, and 3mm thick, with 10mm and 20mm bending areas at both ends along the width direction; and the small rib plate blank is 240mm wide, 1500mm long, and 3mm thick. The thickness of all three blanks is consistent with the wall thickness of the electrode cylinder 1 shell. In step S4, the small rib plate blank is fed into a shearing machine, with the shearing stop set to 375mm, and is cut along the length direction to obtain a 240mm×375mm×3mm small rib plate 4. The width direction of the small rib plate 4 corresponds to the circumferential bonding direction, and the length direction corresponds to the axial bridging direction.

[0049] The width of the widened stiffener blank is 375mm, which is 45mm wider than the conventional stiffener blank width of 330mm. This provides a larger radial heat dissipation area and a larger conductive cross-sectional area for the widened stiffener 3. Bending areas of 10mm and 20mm are set at both ends along the width direction. The folded edge structure formed after bending can achieve surface contact welding with the inner wall of the electrode cylinder 1 shell, which improves the welding strength and conductivity reliability. The design of the small stiffener 4 with dimensions of 240mm×375mm×3mm takes into account both the convenience of welding operation and the axial conductive cross-sectional area requirement. The axial length of 375mm ensures that it forms a sufficient overlap length between the upper and lower widened stiffeners 3. The circumferential width of 240mm matches the fit width of the side of the widened stiffener 3, ensuring that the conductive path after welding has low resistance characteristics.

[0050] Furthermore, prior to S5, the process also includes: placing regular stiffening plate blanks, widened stiffening plate blanks, and small stiffening plate blanks on the stiffening plate loading platform, performing punching and bending processes in sequence, and then hoisting them from the unloading platform to the assembly frame unloading platform.

[0051] In practice, the three types of blanks are hoisted to the stacking position on the loading platform in batches. The loading suction cups pick up each blank and send it to the punching station to punch horizontal rectangular holes, and then send it to the bending station for edge bending. After processing, the stiffening plates are stacked on the collection rack by the unloading suction cups. After accumulating a certain number, they are hoisted as a whole to the unloading platform of the adjacent assembly tray for use in step S5.

[0052] The modified rib plate feeding system enables continuous automated processing of three different widths of blanks on the same production line, avoiding the need to configure a separate production line for new specifications and saving approximately 500,000 yuan in equipment investment. The continuous operation of feeding, punching, bending, feeding, and hoisting reduces the space occupied by intermediate storage and the amount of secondary handling work. Even with an increase in the types of materials, no additional operators were needed, and the feeding volume increased by 17 tons, improving labor efficiency. The processed rib plates are temporarily stored on the material release platform adjacent to the assembly tray, facilitating quick access during the assembly process and shortening the material transfer distance.

[0053] Furthermore, before S6, it also includes: welding the sheared small stiffening plate 4 to the bottom of the electrode cylinder 1, and then using a single beam crane to lift the electrode cylinder 1 to the ring for docking; in S6, the welding specifically includes: using an F wrench to press the small stiffening plate 4 tightly against the stiffening plate of the lower electrode cylinder 1, and then placing the widened stiffening plate 3 in the inner corner direction before welding and fixing it.

[0054] In practice, firstly, small stiffening plates 4 are welded to the inner side of the lower cylinder wall of the assembled electrode cylinder 1 at the position corresponding to the widening stiffening plate 3, so that the lower half of the small stiffening plate 4 extends out of the bottom end of the shell. A single-beam crane lifts the electrode cylinder 1 into the ring, axially aligns it with the lower electrode cylinder 1, and rotates it to align with the widening stiffening plate 3. Then, an F-wrench is used to press the side of the small stiffening plate 4 tightly against the side of the lower widening stiffening plate 3, and fully welds it along the contact edge to form a conductive connection bridge bridging the upper and lower widening stiffening plates 3.

[0055] Before hoisting, the small stiffener 4 is pre-welded to the bottom of the electrode cylinder 1, which simplifies the difficulty of high-altitude welding operations inside the ring and improves operational safety. After welding, the side of the small stiffener 4 is pressed tightly against the side of the lower widened stiffener 3 using an F-wrench, ensuring close contact of the welding surfaces and avoiding increased contact resistance or incomplete welding caused by gaps. The formed conductive connection bridge is located in the inner corner area, which is the main current axial conduction path. This structure greatly increases the conductive contact area at the connection, reduces contact resistance, and can carry a larger axial current without generating local overheating.

[0056] Furthermore, in S6, the widening stiffeners 3 are concentrated in the inner corner area of ​​the electrode cylinder 1, and the small stiffeners 4 are welded tightly to the widening stiffeners 3 of the lower electrode cylinder 1 to form an enhanced conductive path in the inner corner area.

[0057] In practice, the widened stiffener 3 is concentrated in the inner corner area (the high-temperature main current area facing the furnace core) in step S5. After welding, the current flows through the upper widened stiffener 3, the small stiffener 4, and the weld interface to the lower widened stiffener 3, forming a continuous axial conductive path. The conductive cross-sectional area is larger than that of the traditional end-face contact structure, resulting in lower contact resistance.

[0058] This structure overcomes the inherent defects of traditional electrode cylinders where the connection between the upper and lower sections relies solely on the contact between the shell end faces or the tiny contact surfaces at the ends of the stiffeners for conductivity. In traditional structures, the shell end faces have high contact resistance and are prone to arcing and burning due to gaps caused by thermal expansion. This method establishes a conductive bridge in the inner corner region by welding small stiffeners 4 to the side walls of the upper and lower widened stiffeners 3, creating a reliable axial current path between the upper and lower electrode cylinder sections 1. Because the contact area between the small stiffeners 4 and the side of the widened stiffeners 3 is much larger than the contact area of ​​the stiffener end faces, this conductive path has lower contact resistance and stronger current carrying capacity. It can maintain conductivity stability under high-load operation of the calcium carbide furnace, avoiding stiffener melting due to overheating at the connection and preventing electrode soft breakage accidents caused by overheating at the connection.

[0059] Furthermore, in S6, there is a preset length difference between the bottom end of the widening stiffener 3 and the bottom end of the electrode cylinder 1 shell, so that after the upper and lower adjacent electrode cylinders 1 are connected, an axial flow guide gap is formed between the bottom end of the widening stiffener 3 in the upper electrode cylinder 1 and the top surface of the lower electrode cylinder 1 shell; the axial flow guide gap is used to allow the high temperature gas in the electrode cylinder 1 to flow axially, and at the same time, the widening stiffener 3 is electrically connected to the widening stiffener 3 of the lower electrode cylinder 1 through the small stiffener 4 welded to its bottom end.

[0060] In practical implementation, during manufacturing, the axial length of the widened stiffener 3 is controlled to be 5mm to 10mm shorter than the bottom end of the electrode cylinder 1 shell. After the upper and lower electrode cylinders 1 are joined, an axial flow-guiding notch with a height of 5mm to 10mm is formed between the bottom end of the upper widened stiffener 3 and the top surface of the lower shell. High-temperature gas can flow axially through the notch, avoiding the accumulation and erosion of flue gas at the root of the stiffener; axial conductivity is achieved by welding the side of the small stiffener 4, and the notch does not affect the continuity of conductivity.

[0061] The axial flow-guiding notch provides an axial flow channel for the high-temperature volatile gases generated during the electrode paste sintering process, preventing the gas from accumulating at the root of the rib plate at the joint of the upper and lower electrode cylinders 1 and forming eddies, thereby preventing the problem of local ablation at the root of the rib plate due to flue gas accumulation. The conductive function and the gas guiding function are structurally designed separately: the axial current is conducted through the welding path on the side of the small rib plate 4, without relying on the bottom end face contact of the widened rib plate 3; the existence of the axial flow-guiding notch does not affect the conductive connection. The functional separation design ensures that the thermal stability and electrical stability of the electrode cylinder 1 are guaranteed under high load operating conditions, which not only solves the problem of local burn-out caused by poor flue gas emission, but also ensures the reliable conduction of axial current, extends the service life of the electrode cylinder 1, and improves the safety of the calcium carbide furnace operation.

Claims

1. A method for optimizing the structure of an electrode cylinder in a calcium carbide furnace, characterized in that: Includes the following steps: S1: The electrode cylinder assembly plate is processed by cutting inward on the basis of the original groove depth to form a stepped positioning groove with a depth difference, so that the widened stiffener (3) and the conventional stiffener (2) are positioned on the assembly plate with the same outer diameter reference surface. S2: Modify the stiffener blanking system so that it can simultaneously punch and fold at least three different specifications of steel plates, including conventional stiffener blank specifications, widened stiffener blank specifications, and small stiffener blank specifications. S3: Replace the punching machine mold with a square horizontal hole mold to punch a horizontal rectangular hole on the rib plate. The area of ​​the horizontal rectangular hole is larger than the area of ​​the original C-shaped hole. S4: Use a shearing machine to cut the steel plate of the small stiffener blank into small stiffeners of the preset size (4). S5: Assemble the ribs and arc plates on the assembly plate. Mix conventional ribs (2) and widened ribs (3) in the same electrode cylinder (1). The radial width of the widened ribs (3) is greater than that of the conventional ribs (2). The widened ribs (3) are concentrated in the first arc-shaped area of ​​the electrode cylinder (1) corresponding to the high temperature zone of the furnace core. The conventional ribs (2) are arranged in the second arc-shaped area of ​​the electrode cylinder (1) corresponding to other areas in the furnace. The first arc-shaped area and the second arc-shaped area together form a complete circumferential distribution. S6: Position the inner corner area within the ring, weld the small stiffener (4) to the bottom end of the widening stiffener (3), and weld the widening stiffener (3) to the inner corner area, so that the upper and lower adjacent electrode cylinders (1) form an enhanced axial conductive path in the inner corner area.

2. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S1, the depth of the inward cut is 45mm, and the depth difference of the stepped positioning groove is 45mm.

3. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S5, the radial width of the conventional stiffening plate (2) is 270mm, the radial width of the widened stiffening plate (3) is 315mm, and the radial width is increased by 45mm; the number of conventional stiffening plates (2) is 8 or 10, and the number of widened stiffening plates (3) is 6.

4. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S3, the length direction of the transverse rectangular hole is parallel to the radial direction of the electrode cylinder (1) shell; the heat-conducting hole distribution density on the widened stiffener (3) is greater than the heat-conducting hole distribution density on the conventional stiffener (2).

5. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S5, the first arc-shaped region is symmetrically extended to both sides with the shell position of the electrode cylinder (1) corresponding to the furnace core direction as the center reference point; the widened stiffener (3) is evenly arranged at equal intervals in the first arc-shaped region, and the conventional stiffener (2) is evenly arranged at equal intervals in the second arc-shaped region.

6. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S2, the three different specifications of steel plates are 330×1498×3mm for conventional stiffening plate blanks, 375×1498×3mm for widened stiffening plate blanks, and 240×1500×3mm for small stiffening plate blanks; in S4, the preset size of the small stiffening plate (4) is 240×375×3mm.

7. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: Prior to S5, the process also included placing regular stiffening plate blanks, widened stiffening plate blanks, and small stiffening plate blanks on the stiffening plate loading platform, performing punching and bending processes in sequence, and then hoisting them from the unloading platform to the assembly frame unloading platform.

8. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: Before S6, it also includes: welding the sheared small stiffening plate (4) to the bottom of the electrode cylinder (1), and then using a single beam crane to lift the electrode cylinder (1) to the ring for docking; in S6, the welding specifically includes: using an F wrench to press the small stiffening plate (4) against the stiffening plate of the lower electrode cylinder (1), and then placing the widened stiffening plate (3) in the inner corner direction for welding and fixing.

9. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S6, the widening stiffener (3) is concentrated in the inner corner area of ​​the electrode cylinder (1), and the small stiffener (4) is welded to the widening stiffener (3) of the lower electrode cylinder (1) to form an enhanced conductive path in the inner corner area.

10. The method for optimizing the structure of an electrode cylinder in a calcium carbide furnace according to claim 1, characterized in that: In S6, there is a preset length difference between the bottom end of the widening stiffener (3) and the bottom end of the electrode cylinder (1) shell, so that after the upper and lower adjacent electrode cylinders (1) are connected, an axial flow guide gap is formed between the bottom end of the widening stiffener (3) in the upper electrode cylinder (1) and the top surface of the lower electrode cylinder (1) shell; the axial flow guide gap is used to allow the high temperature gas in the electrode cylinder (1) to flow axially, and at the same time, the widening stiffener (3) is electrically connected to the widening stiffener (3) of the lower electrode cylinder (1) through the small stiffener (4) welded to its bottom end.

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