A step-by-step commissioning method for short-grid side path insulation of a submerged arc furnace

Abstract

This invention provides a step-by-step insulation debugging method for the short-circuit side path of a submerged arc furnace (SAF). This method includes the following steps: an electrical circuit inspection step, where the electrical circuits on the short-circuit side of the SCF are inspected and adjusted; and an insulation debugging step, where, after the electrical circuit inspection is completed, insulation debugging is performed on each structural component of the SCF path using a current generator based on the short-circuit current method. During insulation debugging, each structural component of the SCF path is divided into three main sections: the furnace body, the furnace top, and the electrode columns. Each section undergoes progressive short-circuit current insulation debugging on adjacent structures along the short-circuit side. This invention, by inspecting the electrical circuits before short-circuit debugging and using the short-circuit current method to progressively debug adjacent structures along the short-circuit side section, enables testing and debugging of different components along the short-circuit test path, thus overcoming the current limitation that insulation testing on the short-circuit side of a SCF cannot be visually tested using a megohmmeter.

Description

Technical Field

[0001] This invention relates to the field of electrical engineering technology, and more specifically, to a method for step-by-step commissioning of insulation on the short-circuit side of a submerged arc furnace. Background Technology

[0002] In the handover or preventative testing of power supply and distribution equipment, insulation testing of electrical equipment is essential. The short network is a general term for the secondary busbar connection path from the secondary terminal of the single-phase transformer in a submerged arc furnace to the furnace electrodes. The short network consists of several crisscrossing water-cooled copper pipes, wall-penetrating supports, and hanging components. Its insulation performance directly determines whether the electrical system can operate safely under power, and is directly related to the stability of the submerged arc furnace's start-up and production operation.

[0003] Currently, the commonly used method for debugging short-circuit insulation is the low-pass voltage method. Typically, an AC 380V voltage source is connected to the primary side of three single-phase transformers. After transformation, a low voltage of about 1V is induced on the short-circuit side. By measuring the primary side voltage and current, and comparing them with the phase-to-phase and phase-to-ground voltages on the short-circuit side, it is determined whether the insulation of the short-circuit path is good.

[0004] During insulation testing between different components on the short network side path, due to the wide lateral extension and high longitudinal density between the components and the steel structure, the insulation value measured by the insulation megohmmeter shows a short circuit state, and the insulation megohmmeter cannot effectively test the insulation condition between them. Summary of the Invention

[0005] In view of this, the present invention proposes a step-by-step commissioning method for the short-circuit side path insulation of a submerged arc furnace, which aims to solve the problem of the existing short-circuit insulation commissioning method using the low-pass voltage method.

[0006] This invention proposes a step-by-step insulation debugging method for the short-circuit side path of a submerged arc furnace. This method includes the following steps: an electrical circuit inspection step, where the electrical circuits on the short-circuit side of the submerged arc furnace are inspected and adjusted; an insulation debugging step, where, after the electrical circuit inspection is completed, insulation debugging is performed on each structural component of the short-circuit side path of the submerged arc furnace using a current generator based on the short-circuit current method; during insulation debugging, each structural component of the short-circuit side path of the submerged arc furnace is divided into three major sections: the furnace body, the furnace top, and the electrode columns, and each section undergoes progressive short-circuit current insulation debugging using adjacent structures on the short-circuit side path.

[0007] Furthermore, the above-mentioned step-by-step debugging method for short-circuit side path insulation of the submerged arc furnace includes the following sub-steps for debugging the furnace body area path insulation: Furnace bottom rotating table and track insulation test sub-step, connecting the negative lead of the current generator to the furnace bottom rotating table, and lapping the positive clamp of the current generator to the metal track set on the furnace bottom rotating table, and performing insulation debugging between the two; Furnace body and track insulation test sub-step, connecting the negative lead of the current generator to the metal track, and lapping the positive clamp of the current generator to the furnace body, and performing insulation debugging between the two; Burn-through device and burn-through device track insulation test sub-step, connecting the negative lead of the current generator to the burn-through device, and lapping the positive clamp of the current generator to the burn-through device track, and performing insulation debugging between the two; Fume hood and furnace body insulation test sub-step, connecting the negative lead of the current generator to the furnace body, and lapping the positive clamp of the current generator to the flue, and performing insulation debugging between the two.

[0008] Furthermore, the above-mentioned step-by-step debugging method for the short-circuit side path insulation of the submerged arc furnace includes the following sub-steps for debugging the path insulation in the furnace top area: a sub-step for testing the insulation between the hopper and the feed pipe, where the negative lead of the current generator is connected to the hopper, the positive clamp of the current generator is connected to the feed pipe, and insulation debugging is performed between the two; a sub-step for testing the insulation between the feed pipe and the track, where the negative lead of the current generator is connected to the feed pipe, the positive clamp of the current generator is connected to the furnace body, and insulation debugging is performed between the two; a sub-step for testing the insulation between the nozzle and the furnace cover, where the negative lead of the current generator is connected to the nozzle component, the positive clamp of the current generator is connected to the furnace cover component, and insulation debugging is performed between the two.

[0009] Furthermore, the above-mentioned step-by-step debugging method for short-circuit side path insulation of the submerged arc furnace includes the following sub-steps for the electrode column area path insulation debugging: Copper pipe and hanger insulation test sub-step: connect the negative lead of the current generator to the copper pipe, overlap the positive clamp of the current generator with the hanger, and perform insulation debugging between the two; Flue and furnace cover insulation test sub-step: connect the negative lead of the current generator to the flue, overlap the positive clamp of the current generator with the furnace cover, and perform insulation debugging between the two; Edge furnace cover insulation test sub-step: connect the negative lead of the current generator and the positive clamp of the current generator to two adjacent edge furnace covers respectively, and perform insulation debugging between the two; Center furnace cover insulation test sub-step: connect the negative lead of the current generator and the positive clamp of the current generator to two adjacent center furnace cover components respectively, and perform insulation debugging between the two; Center furnace cover and edge furnace cover insulation test sub-step: connect the current generator... The negative lead of the current generator and the positive clamp of the current generator are connected to the adjacent central furnace cover and edge furnace cover components, respectively, and insulation testing is performed between them; In the insulation test sub-step between the guide wheel and the sealing ring, the negative lead of the current generator is connected to the guide wheel component, and the positive clamp of the current generator is briefly overlapped with the sealing ring component, and insulation testing is performed between them; In the insulation test sub-step between the pressure ring and the copper tile, the negative lead of the current generator is connected to the pressure ring, and the positive clamp of the current generator is overlapped with the copper tile, and insulation testing is performed between them; In the insulation test sub-step between the copper tile and the protective screen, the negative lead of the current generator is connected to the copper tile, and the positive clamp of the current generator is overlapped with the protective screen installed outside the copper tile, and insulation testing is performed between them; In the insulation test sub-step between the brake and the brake base, the negative lead of the current generator is connected to the brake, and the positive clamp of the current generator is overlapped with the brake base, and insulation testing is performed between them.

[0010] Furthermore, in the above-mentioned step-by-step debugging method for the short-circuit side insulation of the electric arc furnace, if the voltage meter on the current generator instrument interface does not change abruptly when adjacent structures are overlapped, then the insulation test of each path of the short-circuit is qualified; if the voltage meter reading at the overlapped part decreases, then there is a short circuit between the overlapped parts. The cause and point of the short circuit should be found, and after handling, the current generator overlap debugging should continue.

[0011] Furthermore, the above-mentioned step-by-step commissioning method for short-circuit side path insulation of the submerged arc furnace includes the following sub-steps in the electrical circuit inspection process: Inspect the electrical circuits of the three single-phase transformers and short-circuit the primary and tertiary side terminals to ground; inspect and test the transformer upstream switchgear to ensure it is in the test position; inspect and test the ABC phase low-voltage capacitor compensation electrical room on the short-circuit side, and ensure the capacitor compensation cabinet knife switch and contactor are in the open position; check the connection between the copper pipe and the single-phase transformer, and the connection between the copper pipe and the water cooling device, checking for reliability, and adjusting if unreliable; check the stability of the connection between the copper pipe and the wall-penetrating bracket; check the reliability of the connection between the copper pipe and the hanging contact surface; check for debris at the copper tile, copper pipe bend, and connection surface with the copper tile, cleaning if necessary; check the tightness of the connection between the electrode post and the copper tile.

[0012] Furthermore, the above-mentioned step-by-step debugging method for the short-circuit side path insulation of the electric arc furnace includes the following steps before the electrical circuit inspection step: preparatory work, determining the scope of the work area, various structural components on the short-circuit side, and the electrical schematic diagram of the short-circuit.

[0013] The present invention provides a step-by-step commissioning method for the insulation of the short-circuit side path of a submerged arc furnace. Before short-circuit commissioning, the electrical circuits are inspected, and the short-circuit current method is used to progressively commission adjacent structures of the short-circuit side path, segment by segment. This allows for testing and commissioning of different components of the short-circuit side path, overcoming the limitation that a megohmmeter cannot be used for direct insulation testing of the short-circuit side of the submerged arc furnace. This ensures the quality of the short-circuit side path system commissioning, shortens the commissioning period, significantly increases the insulation of the short-circuit side system, reduces the safety risks of system testing and commissioning, stabilizes the operation cycle of furnace start-up, maintenance, and production, and saves costs. Performing short-circuit current testing and commissioning on different components of the electrical path on the short-circuit side ensures the quality of electrical system commissioning, accurately and efficiently reflects the insulation status of the short-circuit path, and guarantees the safety of testing personnel, the testing process, and the testing equipment. Furthermore, this method also has the following advantages:

[0014] 1. Provide high-voltage equipment for electric arc furnaces with improved short-circuit insulation safety factor during handover maintenance and testing, ensuring the reliability and stability of the testing process;

[0015] 2. It saved labor costs, shortened the debugging cycle of short network paths, and ensured the debugging quality of electrical systems;

[0016] 3. It is easy to use and operate, and the debugging steps are clear. Compared with the low-pass voltage method, it can accurately and efficiently reflect the insulation status of the short network side diameter.

[0017] 4. After the test, the site is cleaned up quickly and safely without leaving any hidden dangers, which greatly improves the efficiency of short-circuit side path insulation testing and personnel safety. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0019] Figure 1 This is a schematic diagram of the structure of the short grid side path of the electric arc furnace provided in an embodiment of the present invention;

[0020] Figure 2 A flowchart illustrating the step-by-step commissioning method for short-grid side path insulation of a submerged arc furnace provided in an embodiment of the present invention;

[0021] Figure 3 A schematic block diagram illustrating the debugging sequence of the short network path provided in an embodiment of the present invention;

[0022] Figure 4 This is another flowchart of the step-by-step commissioning method for short-grid side path insulation of a submerged arc furnace provided in an embodiment of the present invention;

[0023] Figure 5 A flowchart for furnace body area path insulation debugging provided in an embodiment of the present invention;

[0024] Figure 6 A flowchart illustrating the process of debugging the path insulation in the furnace top area, as provided in an embodiment of the present invention.

[0025] Figure 7 A flowchart for electrode post area path insulation debugging provided in an embodiment of the present invention;

[0026] Figure 8 A flowchart illustrating the electrical circuit inspection steps provided in an embodiment of the present invention. Detailed Implementation

[0027] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] See Figure 1This is a schematic diagram of the structure of the short-grid side path of the electric arc furnace provided in an embodiment of the present invention. As shown in the figure, the short-grid side path of the electric arc furnace includes: a furnace bottom rotary table 8, an electric furnace body 7, and three unidirectional transformers 1; wherein,

[0029] The furnace bottom rotating platform 8 provides support and is equipped with metal tracks for guiding the rotation of the electric furnace body 7. The electric furnace body 7 is positioned above the furnace bottom rotating platform 8, allowing it to rotate along the metal tracks. The electric furnace body 7 holds silica, wood chips, and coal. Three electrode posts 5 are located above the electric furnace body 7, each equipped with a copper tile 6. Each copper tile 6 is connected to a corresponding unidirectional transformer 1 via a copper pipe 4. The three electrode posts 5 can move up and down to penetrate into the electric furnace body 7. Through a short circuit between the three electrode posts 5, the silica, wood chips, and coal can then form molten silica. The electrode posts 5 are equipped with brakes to allow for vertical movement; the copper pipes 4 are equipped with hangers 3 for fixation; the unidirectional transformer 1 is located outside the wall 2, and the copper pipes 4 can pass through the wall 2 to connect to the copper tiles 6 installed inside the wall 2. The electric furnace body 7 is provided with several discharge holes, and a blocking block can be installed at each discharge hole. During discharge, the blocking block can be removed from the discharge hole, allowing the hot molten silicon to drain. The electric furnace body 7 is provided with a burn-through track 9 arranged along its outer periphery. A burn-through device 10 is installed on the burn-through track 9 and can rotate along the burn-through track 9 to move to the discharge hole and remove the corresponding blocking block. A furnace cover 11 is also provided above the electric furnace body 7. The furnace cover 11 includes several central furnace covers and several edge furnace covers corresponding to the central furnace covers. The central furnace covers surround a central portion, and the edge furnace covers are arranged around the outer periphery of the central portion. The central furnace covers are used to fix and support the electrode columns, etc., while the edge furnace covers can support the flue 12, the feeding pipe 13, etc.

[0030] See Figure 2 This is a flowchart illustrating the step-by-step insulation commissioning method for the short-grid side path of a submerged arc furnace provided in an embodiment of the present invention. As shown in the figure, the step-by-step insulation commissioning method includes the following steps:

[0031] Electrical circuit inspection step S1: Inspect and adjust the electrical circuits on the short network side of the electric arc furnace.

[0032] Specifically, the electrical circuits on the short grid side of the electric arc furnace can be inspected and adjusted first to ensure the safety of the insulation commissioning on the short grid side of the electric arc furnace.

[0033] In insulation commissioning step S2, after the electrical circuit inspection of the short grid side of the electric arc furnace is completed, insulation commissioning is carried out on each structural component of the short grid side path of the electric arc furnace based on the short-circuit current method using a current generator instrument. During insulation commissioning, each structural component of the short grid side path of the electric arc furnace is divided into three major sections: furnace body, furnace top and electrode column. Each section is subjected to progressive short-circuit current insulation commissioning with each adjacent structure of the short grid side path.

[0034] Specifically, the structural components of the short-circuit side path of the electric arc furnace can be divided into three major sections: furnace body, furnace top, and electrode column. Then, the insulation of these three sections is tested sequentially using the short-circuit current method. The insulation testing of the three sections can proceed sequentially from furnace body to furnace top to electrode column; other orders are also possible, and this embodiment does not impose any limitations. During the insulation testing of each section, the short-circuit current method is used. A current generator instrument is used to progressively test the insulation of each adjacent structure within each section using a step-by-step short-circuit current method, overcoming the limitation that a megohmmeter cannot be used for direct insulation testing on the short-circuit side of the electric arc furnace. If the voltage reading on the current generator instrument does not change abruptly when adjacent structures are connected (i.e., when the negative lead and positive clamp of the current generator are connected to adjacent structures for insulation testing), then the insulation test of each path in the short-circuit test is qualified. If the voltage reading at the connection point decreases, a short circuit exists between the connected components. The cause and point of the short circuit are located, and the current generator connection testing continues until the voltage reading on the current generator instrument does not change abruptly during insulation testing. In this embodiment, when each module undergoes progressive short-circuit current insulation testing using adjacent structures along the short-circuit side path, it can be done according to... Figure 3 The insulation is adjusted step by step along the path. That is, in the furnace body module: furnace bottom rotary table 8 → electric furnace body 7 → metal track → burn-through device 10 → fume hood i.e. flue 12; in the furnace top module: hopper → material pipe i.e. feeding pipe 13 → material nozzle; in the electrode column module: electrode column → hanging 3 → copper pipe 4 → flue 12 → furnace cover 11, electrode column → guide wheel → sealing ring, electrode column → bottom ring → pressure ring → copper tile 6 → protective screen, electrode column → brake.

[0035] See Figure 4 This is another flowchart illustrating the step-by-step insulation commissioning method for the short-grid side path of a submerged arc furnace provided in this embodiment of the invention. As shown in the figure, the step-by-step insulation commissioning method includes the following steps:

[0036] Preparation work S3: Determine the scope of the work area, the various structural components on the short network side, and the electrical schematic diagram of the short network.

[0037] Specifically, the preparation work for commissioning can begin by confirming the scope of the work area; setting up warning lines and hanging warning signs, and preparing fire extinguishers; then, familiarizing oneself with the paths of each structural component on the short network side; and being familiar with the electrical schematic diagram of the short network; finally, preparing the instruments, meters, equipment, and auxiliary tools for commissioning, such as current generators, digital multimeters, walkie-talkies, wrenches, screwdrivers, etc.

[0038] Electrical circuit inspection step S1: Inspect and adjust the electrical circuits on the short network side of the electric arc furnace.

[0039] In insulation commissioning step S2, after the electrical circuit inspection of the short grid side of the electric arc furnace is completed, insulation commissioning is carried out on each structural component of the short grid side path of the electric arc furnace based on the short-circuit current method using a current generator instrument. During insulation commissioning, each structural component of the short grid side path of the electric arc furnace is divided into three major sections: furnace body, furnace top and electrode column. Each section is subjected to progressive short-circuit current insulation commissioning with each adjacent structure of the short grid side path.

[0040] See Figure 5 This is a flowchart of the furnace body area path insulation debugging provided in the embodiment of the present invention.

[0041] As shown in the figure, the furnace body area path insulation debugging includes the following sub-steps:

[0042] In the sub-step S211 of the furnace bottom rotary table and track insulation test, the negative terminal lead of the current generator is connected to the furnace bottom rotary table, the positive terminal clamp of the current generator is connected to the metal track set on the furnace bottom rotary table, and the insulation between the two is adjusted.

[0043] In the furnace body and track insulation test sub-step S212, the negative terminal lead of the current generator is connected to the metal track, the positive terminal clamp of the current generator is connected to the furnace body, and the insulation between the two is adjusted.

[0044] In the burn-through device and burn-through device track insulation test sub-step S213, connect the negative terminal lead of the current generator to the burn-through device, connect the positive terminal clamp of the current generator to the burn-through device track, and perform insulation testing between the two.

[0045] In sub-step S214 of the insulation test between the fume hood and the furnace body, connect the negative lead of the current generator to the furnace body, connect the positive clamp of the current generator to the flue, and perform insulation testing between the two.

[0046] See Figure 6 This is a flowchart of the furnace top area path insulation debugging provided in the embodiment of the present invention.

[0047] As shown in the figure, the insulation debugging of the furnace top area path includes the following sub-steps:

[0048] In the insulation test sub-step S221 between the hopper and the feed pipe, the negative lead of the current generator is connected to the hopper, the positive clamp of the current generator is connected to the feed pipe, and the insulation between the two is tested. Specifically, the top of the feed pipe 13 is connected to a hopper for feeding material into the feed pipe 13 so that the material is guided into the furnace body 7.

[0049] In the insulation test sub-step S222 between the feed tube and the furnace body, connect the negative lead of the current generator to the feed tube, connect the positive clamp of the current generator to the furnace body, and perform insulation testing between the two.

[0050] In sub-step S223 of the insulation test between the nozzle and the furnace cover, the negative lead of the current generator is connected to the nozzle component, the positive clamp of the current generator is connected to the furnace cover component, and the insulation between the two is adjusted. Specifically, the discharge port of the feeding pipe 13 is equipped with a nozzle component for discharging materials.

[0051] See Figure 7 This is a flowchart illustrating the electrode post area path insulation debugging process provided in this embodiment of the invention. As shown in the figure, the electrode post area path insulation debugging includes the following sub-steps:

[0052] In the copper pipe and hanging insulation test sub-step S231, connect the negative lead of the current generator to the copper pipe, connect the positive clamp of the current generator to the hanging, and perform insulation testing between the two.

[0053] In the insulation test sub-step S232 between the flue and the furnace cover, connect the negative lead of the current generator to the flue, overlap the positive clamp of the current generator with the furnace cover, and perform insulation testing between the two.

[0054] In the insulation test sub-step S233 between edge furnace covers, connect the negative terminal lead of the current generator and the positive terminal clamp of the current generator to the two adjacent edge furnace covers respectively, and perform insulation testing between them.

[0055] In the insulation test sub-step S234 between the central furnace covers, the negative terminal lead of the current generator and the positive terminal clamp of the current generator are connected to the two adjacent central furnace cover components respectively, and the insulation between them is adjusted.

[0056] In the insulation test sub-step S235 between the center furnace cover and the edge furnace cover, the negative terminal lead of the current generator and the positive terminal clamp of the current generator are connected to the adjacent center furnace cover and edge furnace cover components, respectively, and the insulation between them is adjusted.

[0057] In sub-step S236 of the insulation test between the guide wheel and the sealing ring, the negative terminal lead of the current generator is connected to the guide wheel assembly, the positive terminal clamp of the current generator is briefly overlapped with the sealing ring assembly, and insulation adjustment is performed between the two. Specifically, the guide wheel is used to guide the up and down movement of the electrode post 5, and the sealing ring is placed between the guide wheel and the electrode post 5.

[0058] In sub-step S237 of the insulation test between the pressure ring and the copper tile, the negative lead of the current generator is connected to the pressure ring, the positive clamp of the current generator is overlapped with the copper tile, and insulation adjustment is performed between the two. Specifically, the copper tile 6 wraps around the outer periphery of the electrode post 5, and a pressure ring is provided between the copper tile 6 and the electrode post 5.

[0059] In the copper tile and protective screen insulation test sub-step S238, connect the negative lead of the current generator to the copper tile, overlap the positive clamp of the current generator with the protective screen installed outside the copper tile, and perform insulation testing between the two.

[0060] In sub-step S239 of the brake-base insulation test, the negative lead of the current generator is connected to the brake, the positive clamp of the current generator is connected to the brake base, and insulation testing is performed between the two. The brake base is used to straighten the brake 14, and the brake 14 is used to move the electrode post 5 up and down.

[0061] See Figure 7 This is a flowchart of the electrical circuit inspection steps provided in an embodiment of the present invention. As shown in the figure, the electrical circuit inspection step S1 includes the following sub-steps:

[0062] Sub-step S11 involves inspecting the electrical circuits of the three single-phase transformers and short-circuiting the primary and tertiary terminals to ground. Specifically, the primary and tertiary terminals of the three single-phase transformers are short-circuited to ground to prevent voltage induction from the short-circuit side to the high-voltage side of the single-phase transformers during short-circuit testing.

[0063] Sub-step S12 involves inspecting and testing the upstream switchgear of the transformer to ensure it is in the test position. Specifically, the upstream switchgear is used to control the single-phase transformer. When the switch in the switchgear is closed, a voltage input of, for example, 35kV is applied to the transformer. The upstream switchgear has two positions: a test position and a working position. The test position is used for testing the switchgear. The upstream switchgear corresponding to the three single-phase transformers is inspected and tested sequentially to ensure that they are all in the test position, the grounding switch is in the closed position, and the feeder cable terminations and shielding connections are correct.

[0064] Sub-step S13 involves inspecting and testing the low-voltage capacitor compensation electrical room for phases ABC on the short-circuit side, and ensuring that the disconnect switches and contactors of the capacitor compensation cabinet are in the open position. Specifically, in the low-voltage capacitor compensation electrical room for phases ABC on the short-circuit side, check that the disconnect switches and contactors of the capacitor compensation cabinet are in the open position.

[0065] Sub-step S14 involves checking the connection between the copper pipe and the unidirectional transformer, and the connection between the copper pipe and the water cooling device. The reliability of these connections is checked, and adjustments are made if necessary. Specifically, copper pipe 3 is a water-cooled copper pipe containing water for cooling. The reliability of the connection between copper pipe 3 and the unidirectional transformer 1, as well as the connection between copper pipe 3 and the water cooling device, can be checked.

[0066] Sub-step S15: Check the stability of the connection between the copper pipe and the through-wall bracket. Specifically, the wall 2 is equipped with a sleeve and a through-wall bracket. Adjust and check the installation of the copper pipe to ensure a stable connection between the copper pipe and the through-wall bracket.

[0067] Sub-step S16: Check the reliability of the connection between the copper pipe and the hanging contact surface. Specifically, check the reliability of the contact surface between the short network water-cooled copper pipe and the ceramic hanging surface of the furnace top steel structure.

[0068] Sub-step S17: Check for debris at the copper pipe joints, copper pipe bends, and the connection surface with the copper pipe joints. If any is found, clean it. Specifically, check that there is no debris at the copper pipe joints, copper pipe bends, and the connection surface with the copper pipe joints.

[0069] Sub-step S18: Check the tightness of the connection between the electrode post and the copper tile. Specifically, check the tightness of the connection between the electrode post and the copper tile.

[0070] In summary, the step-by-step commissioning method for short-circuit side path insulation of the submerged arc furnace provided in this embodiment first checks the electrical circuits before short-circuit commissioning, and then uses the short-circuit current method to progressively commission adjacent structures of each section of the short-circuit side path. This allows for testing and commissioning of different components of the short-circuit test path, thus overcoming the current limitation that insulation testing on the short-circuit side of the submerged arc furnace cannot be directly tested using a megohmmeter. This ensures the commissioning quality of the short-circuit side path system of the submerged arc furnace, shortens the commissioning period, significantly increases the insulation of the short-circuit side system of the submerged arc furnace, reduces the safety risks of system testing and commissioning, stabilizes the operation cycle of submerged arc furnace start-up, maintenance, and production, and shortens the commissioning cycle, saving costs. Performing short-circuit current testing and commissioning on different components of the electrical path on the short-circuit side ensures the commissioning quality of the electrical system, accurately and efficiently reflects the insulation status of the short-circuit path, and guarantees the safety of test personnel, the test process, and the test equipment. In addition, this method also has the following advantages:

[0071] 1. Provide high-voltage equipment for electric arc furnaces with improved short-circuit insulation safety factor during handover maintenance and testing, ensuring the reliability and stability of the testing process;

[0072] 2. It saved labor costs, shortened the debugging cycle of short network paths, and ensured the debugging quality of electrical systems;

[0073] 3. It is easy to use and operate, and the debugging steps are clear. Compared with the low-pass voltage method, it can accurately and efficiently reflect the insulation status of the short network side diameter.

[0074] 4. After the test, the site is cleaned up quickly and safely without leaving any hidden dangers, which greatly improves the efficiency of short-circuit side path insulation testing and personnel safety.

[0075] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0076] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0077] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for step-by-step debugging of insulation on the short-circuit side of a submerged arc furnace, characterized in that, Includes the following steps: The electrical circuit inspection procedure involves inspecting and adjusting the electrical circuits on the short network side of the electric arc furnace. After the electrical circuit inspection of the short grid side of the electric arc furnace is completed, insulation commissioning is carried out on each structural component of the short grid side path of the electric arc furnace based on the short-circuit current method using a current generator instrument. During insulation commissioning, each structural component of the short grid side path of the electric arc furnace is divided into three major sections: furnace body, furnace top and electrode column. Each section is subjected to progressive short-circuit current insulation commissioning with each adjacent structure of the short grid side path. The path insulation debugging of the furnace body plate includes the following sub-steps: The insulation test sub-step of the furnace bottom rotary table and track involves connecting the negative lead of the current generator to the furnace bottom rotary table, and lapping the positive clamp of the current generator with the metal track set on the furnace bottom rotary table, and then performing insulation testing between the two. The furnace body and track insulation test sub-step involves connecting the negative lead of the current generator to the metal track, lapping the positive clamp of the current generator to the furnace body, and then performing insulation testing between the two. The insulation test sub-steps for the burn-through device and its track involve connecting the negative lead of the current generator to the burn-through device, lapping the positive clamp of the current generator to the burn-through device track, and then performing insulation testing between the two. The insulation test sub-step between the fume hood and the furnace body involves connecting the negative lead of the current generator to the furnace body, connecting the positive clamp of the current generator to the flue, and then adjusting the insulation between the two. The path insulation debugging of the furnace top plate includes the following sub-steps: The insulation test sub-step between the hopper and the pipe involves connecting the negative lead of the current generator to the hopper, lapping the positive clamp of the current generator onto the pipe, and then performing insulation testing between the two. The insulation test sub-step between the feed pipe and the furnace body involves connecting the negative lead of the current generator to the feed pipe, connecting the positive clamp of the current generator to the furnace body, and then performing insulation testing between the two. The insulation test sub-step between the nozzle and the furnace cover involves connecting the negative lead of the current generator to the nozzle component, lapping the positive clamp of the current generator to the furnace cover component, and then performing insulation testing between the two. The path insulation debugging of the electrode post plate includes the following sub-steps: The copper pipe and hanging insulation test sub-step involves connecting the negative lead of the current generator to the copper pipe, lapping the positive clamp of the current generator to the hanging, and then performing insulation testing between the two. The insulation test sub-step between the flue and the furnace cover involves connecting the negative lead of the current generator to the flue, lapping the positive clamp of the current generator to the furnace cover, and then adjusting the insulation between the two. The insulation test sub-step between edge furnace covers involves connecting the negative lead wire of the current generator and the positive clamp of the current generator to the two adjacent edge furnace covers respectively, and then performing insulation testing between them. The insulation test sub-step between the central furnace covers involves connecting the negative lead wire of the current generator and the positive clamp of the current generator to the two adjacent central furnace cover components, and then performing insulation testing between them. The insulation test sub-step for the center furnace cover and the edge furnace cover involves connecting the negative lead wire of the current generator and the positive clamp of the current generator to the adjacent center furnace cover and edge furnace cover components, respectively, and then performing insulation testing between them. In the insulation test sub-step between the guide wheel and the sealing ring, connect the negative lead of the current generator to the guide wheel component, briefly overlap the positive clamp of the current generator with the sealing ring component, and perform insulation testing between the two. The insulation test sub-step between the pressure ring and the copper tile involves connecting the negative lead of the current generator to the pressure ring, lapping the positive clamp of the current generator onto the copper tile, and then performing insulation testing between the two. The insulation test sub-step for copper tile and protective screen involves connecting the negative lead of the current generator to the copper tile, lapping the positive clamp of the current generator with the protective screen installed outside the copper tile, and then performing insulation testing between the two. The insulation test sub-step for the brake and brake base involves connecting the negative lead of the current generator to the brake, lapping the positive clamp of the current generator to the brake base, and then performing insulation testing between the two. During insulation commissioning, if the voltage meter on the current generator interface does not change abruptly when adjacent structures are overlapped, the insulation test of each path in the short network is qualified; if the voltage meter reading at the overlapped part decreases, there is a short circuit between the overlapped parts. Find the cause and point of the short circuit, and continue the current generator overlap commissioning after handling it.

2. The method for step-by-step debugging of insulation on the short-grid side path of a submerged arc furnace according to claim 1, characterized in that, The electrical circuit inspection steps include the following sub-steps: The electrical circuits of the three single-phase transformers were inspected, and the primary and tertiary terminals were shorted to ground. Inspect and test the upstream switchgear of the transformer to ensure it is in the test position; Inspect and test the electrical room for low-voltage capacitor compensation of phases ABC on the short grid side, and ensure that the knife switch and contactor of the capacitor compensation cabinet are in the open position. Check the connection between the copper pipe and the single-phase transformer, and the connection between the copper pipe and the water cooling device. Check if the connection is reliable. If it is not reliable, adjust it. Check the stability of the connection between the copper pipe and the through-wall bracket; Check the reliability of the connection between the copper pipe and the hanging contact surface; Check for debris at the copper pipes where they meet the copper tiles, at the bends of the copper pipes, and at the joints with the copper tiles. If any debris is found, clean it. Check the tightness of the connection between the electrode post and the copper tile.

3. The method for step-by-step debugging of insulation on the short-grid side path of a submerged arc furnace according to claim 1, characterized in that, Prior to the electrical wiring inspection step, the following steps are also included: Preparation work includes determining the scope of the work area, the various structural components on the short network side, and the electrical schematic diagram of the short network.

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