Safe and efficient dismounting and replacing method for 120 t converter evaporative cooling flue

Abstract

The invention discloses a safe and efficient dismounting and replacing method for a 120 t converter evaporative cooling flue. According to the scheme, the 120 t converter evaporative cooling flue is disassembled and installed through the method, specifically, a non-metal compensator between an evaporative cooler and a tail section flue is installed in place, the tail section flue is hoisted, a main II section flue is hoisted, a main I section flue is hoisted, a furnace mouth section flue is hoisted, and a furnace mouth section flue supporting beam is recovered. The method comprises the following steps of: correcting centers of flues at the sections of an oxygen lance opening and a furnace mouth; correcting and fastening the flues by connecting bolts; correcting and welding a support and a suspension; mounting a movable smoke hood, mounting a heat-insulating suspended ceiling, mounting a charging hole and the oxygen lance opening, piping, testing pressure, mounting and recovering platform plates at each layer, transferring waste materials and cleaning a tower building. The replacement construction process is safely and efficiently completed in a high-quality and high-quality manner, the maintenance cost is saved, and the labor intensity of maintenance personnel is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of flue treatment, and in particular relates to a safe and efficient dismantling and replacing method for a 120t converter vaporization cooling flue. Background Art

[0002] The 120t converter vaporization and cooling flue system is an important part of the converter production equipment. The 120t converter vaporization and cooling flue is a key equipment for converter gas recovery. The method of safe and efficient replacement during the maintenance process is very important. How to complete the replacement safely and efficiently within the effective scheduled maintenance time is crucial. Taking into account the influence of factors such as the long size and heavy weight of the vaporization flue body itself, the 120t converter vaporization and cooling flue must be hoisted in sections. How to ensure the installation quality of the 120t converter vaporization and cooling flue and improve the installation efficiency are the key points to consider.

[0003] How to safely and efficiently dismantle and replace the 120t converter vaporization cooling flue construction operation is a key construction in the converter maintenance. How to fully identify the safety risks during the implementation process, formulate complete and detailed safety precautions, and strictly implement them during the implementation process to ensure safety, efficiency and convenient operation.

[0004] Therefore, in view of the above technical defects, it is urgent to design and develop a safe and efficient dismantling and replacement method for the 120t converter vaporization cooling flue. Summary of the invention

[0005] The object of the present invention is to provide a safe and efficient dismantling and replacement method for a 120t converter vaporization cooling flue;

[0006] The first object of the present invention is achieved as follows: the method comprises the removal of a 120t converter vaporization cooling flue and the installation of a 120t converter vaporization cooling flue;

[0007] The demolition of the 120t converter gasification cooling flue includes: construction preparation, furnace shutdown and signboard, dust cleaning, flue hanging point arrangement, installation and hanging of winch pulley block, tower three-story platform and insulation ceiling demolition, four-story or five-story or six-story platform beams and plates demolition, secondary dust removal hood demolition, separation of movable smoke hood and its lifting mechanism, demolition of movable smoke hood, demolition of furnace mouth section flue, demolition of main section I flue, demolition of main section II flue, and demolition of the final section flue;

[0008] The installation of the 120t converter vaporization cooling flue includes, in sequence: installing the non-metallic compensator between the evaporative cooler and the last section of the flue, hoisting the last section of the flue, hoisting the main section II flue, hoisting the main section I flue, hoisting the furnace mouth section flue, restoring the furnace mouth section flue support beam, calibrating the center of the oxygen gun mouth and the furnace mouth section flue, calibrating each section of the flue and tightening the connecting bolts, calibrating and welding the supports and suspension, installing the movable smoke hood, installing the insulation ceiling, installing the charging port and oxygen gun mouth, piping and pressure testing, installing and restoring the platform plates on each floor, unloading the waste materials and cleaning the tower.

[0009] The scheme of the present invention is a safe and efficient method for dismantling and replacing the 120t converter vaporization cooling flue, which can be completed safely, efficiently, and with high quality and quantity during the replacement construction process, saving maintenance costs and reducing the labor intensity of maintenance personnel. Moreover, the scheme of the present invention has the characteristics of low investment cost, easy implementation, reduced spare parts consumption, and safe and efficient use during the implementation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic diagram of the arrangement of a crane and a winch for a safe and efficient removal and replacement method of a 120t converter vaporization cooling flue in the present invention;

[0011] Figure 2 A schematic diagram of the removal and installation of a movable smoke hood of a safe and efficient removal and replacement method for a 120t converter vaporization cooling flue of the present invention;

[0012] Figure 3 It is a schematic diagram of the removal and installation of a movable smoke hood of a safe and efficient removal and replacement method for a 120t converter vaporization cooling flue of the present invention;

[0013] Figure 4 Three schematic diagrams of the removal and installation of a movable smoke hood of a safe and efficient removal and replacement method for a 120t converter vaporization cooling flue of the present invention;

[0014] Figure 5 The present invention is a schematic diagram of the removal and installation of the furnace mouth section flue of a safe and efficient removal and replacement method for a 120t converter vaporization cooling flue.

[0015] Figure 6 The present invention provides a method for safely and efficiently removing and replacing a 120t converter vaporization cooling flue, and shows two schematic diagrams of removing and installing the furnace mouth section flue.

[0016] Figure 7 Three schematic diagrams of the removal and installation of the furnace mouth section flue of a safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to the present invention.

[0017] Figure 8The present invention is a flow chart of a safe and efficient dismantling and replacing method for a 120t converter vaporization cooling flue. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the accompanying drawings and embodiments so that those skilled in the art can understand the present invention in detail, but the present invention is not limited in any way. Any changes or improvements made based on the technical enlightenment of the present invention belong to the protection scope of the present invention.

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] like Figure 1-8 As shown, the present invention provides a safe and efficient removal and replacement method for a 120t converter vaporization and cooling flue, the method comprising removal of a 120t converter vaporization and cooling flue and installation of a 120t converter vaporization and cooling flue;

[0021] The demolition of the 120t converter gasification cooling flue includes: construction preparation, furnace shutdown and signboard, dust cleaning, flue hanging point arrangement, installation and hanging of winch pulley block, tower three-story platform and insulation ceiling demolition, four-story or five-story or six-story platform beams and plates demolition, secondary dust removal hood demolition, separation of movable smoke hood and its lifting mechanism, demolition of movable smoke hood, demolition of furnace mouth section flue, demolition of main section I flue, demolition of main section II flue, and demolition of the final section flue;

[0022] The installation of the 120t converter vaporization cooling flue includes, in sequence: installing the non-metallic compensator between the evaporative cooler and the last section of the flue, hoisting the last section of the flue, hoisting the main section II flue, hoisting the main section I flue, hoisting the furnace mouth section flue, restoring the furnace mouth section flue support beam, calibrating the center of the oxygen gun mouth and the furnace mouth section flue, calibrating each section of the flue and tightening the connecting bolts, calibrating and welding the supports and suspension, installing the movable smoke hood, installing the insulation ceiling, installing the charging port and oxygen gun mouth, piping and pressure testing, installing and restoring the platform plates on each floor, unloading the waste materials and cleaning the tower.

[0023] In the layout of the winch: the winch is installed in a flat place without obstacles, the distance between the winch drum and the nearest guide pulley is greater than 20 times the length of the drum; when the rope is wound around both ends of the drum, the deflection angle of the wire rope is less than 5°; when the rope is wound around the center of the drum, the center line of the drum and the rope should be perpendicular to each other.

[0024] During the arrangement and construction work of the winch, the hoisting technology combining the winch with a 50t truck crane was adopted; a 50t truck crane was arranged on the 9.1-meter platform of the converter to cooperate with the removal and installation of the flue.

[0025] At least one 16t traction winch is arranged on the 9.1m platform to pull the movable smoke hood and lift the furnace mouth section smoke duct as the main force; at the same time, cooperate with the 50t truck to lift the smoke hood and the furnace mouth section smoke duct to the bottom of the charging straddle car;

[0026] After the winch is arranged, clean the accumulated dust and protectively remove the supporting beams before and after the flue of the furnace mouth section and the platform plates and small beams nearby, remove the beams and plates above the dustproof room, and use a 50t truck crane to remove the secondary dust hood.

[0027] In the method, the removal and installation operation methods of the movable smoke hood are as follows:

[0028] Turn the converter mouth to a horizontal lower position, use four 5t hand chain hoists to hang the movable smoke hood on all sides, detach the movable smoke hood and its lifting mechanism, and simultaneously loosen the four 5t hand chain hoists to place the movable smoke hood flat on the converter shell; then use the traction winch rope to pull the movable smoke hood from the back of the furnace, hang it on the 50t truck, disengage the four hand chain hoist hooks, and then slowly rotate the furnace to cooperate, move out the movable smoke hood, slowly lift it up with the 50t truck crane, untie the traction winch rope, and slowly lift it out of the fire door in front of the furnace with the 50t truck crane, and then place it on the charging span 9.1m platform, and use the crane to transport the movable smoke hood to the open space at the molten iron entrance under the furnace, and wait for it to be transported away later;

[0029] The installation method of the movable smoke hood is the same as the removal method, but the steps are reversed.

[0030] In the method, the removal and installation operation of the furnace mouth section flue is as follows:

[0031] After the movable smoke hood is removed, the furnace mouth section flue begins to be removed. First, the vaporization cooling ascending and descending pipes connected to the furnace mouth section flue are removed, and they are numbered one by one to facilitate later restoration; then the 18.6m and 23.5m platforms and beams are removed;

[0032] Two lifting lugs are welded on the sides of the oxygen gun nitrogen sealing platform beam and the opposite platform beam as the main hoisting 32t pulley rope hanging points. The hanging point is located 2m below the flange connecting the working section and the fixed section. The wire rope is tied to the 32-ton pulley wheel, and the 50-ton truck crane is placed on the outer side of the ring pipe of the flue downcomer header of the furnace mouth section, close to the charging span.

[0033] The main I section flue removal and installation operation method is as follows:

[0034] Arrange at least one 8t load winch on the 33.8m platform, hang a set of pulley No. 2 on the lug under the 44.3m platform beam to dismantle and install the main I section flue, and use the No. 1 pulley set to complete the work;

[0035] The main section I flue removal: when removing this section of flue, first use the main hoisting steel rope of the winch above the section I flue to fix its upper part, and use the winch steel rope above the furnace mouth section to fix its lower part. After the connection between the section I flue and the section II is removed, lower the flue; when the flue falls, use the No. 1 pulley block of the lower winch to adjust the direction of the flue;

[0036] When the main I-section flue descends to the furnace mouth, the converter is used to tilt the furnace shell to move it, and then the charging straddle crane is used to lift out each section of the flue, and then hoisted to the molten iron pretreatment for recycling and disposal;

[0037] The installation method of the main section I flue is the same as the removal method, with the steps being reversed.

[0038] In the method, the removal and installation operation of the main II section flue is as follows:

[0039] At least one 8t and at least one 5t load-carrying winch are arranged on the 44.3m platform. A set of pulleys are hung on the lifting ears under the 56.2m platform beam to dismantle and install the main II section flue, which is completed with the cooperation of No. 2 pulley group. The 8t winch main lifting rope just above the II section flue is used for dismantling. During the descent, the other two winches assist in the descent. The dismantling method when the flue is descended to the furnace mouth is the same as that of the I section flue. The installation method of the main II section flue is the same as that of the dismantling, but the steps are reversed.

[0040] In the method, the method for removing and installing the last section of the flue is as follows:

[0041] When dismantling the last section of the flue, first use three 10t hand hoists to move the flue to the flue mouth, just above the main section II flue, and then use the top 8t winch system to lift it out. During the descent of the flue, the other two winches assist in the descent. The dismantling method when the flue is lowered to the furnace mouth is the same as that of the section II flue.

[0042] The installation method of the final flue section is the same as that of the removal, but the steps are reversed.

[0043] Specifically, in an embodiment of the present invention, a method for safely and efficiently removing and replacing a 120t converter vaporization cooling flue is achieved as follows: Analysis of construction difficulties in replacing a 120t converter vaporization cooling flue:

[0044] The five sections of the converter flue are arranged above the converter span. There is only one 10-meter crane, which cannot meet the lifting capacity of each section of the flue. How to replace the flue safely and efficiently with guaranteed quality and quantity is a difficult point in the construction operation:

[0045] (1) How to hang the flue and lower it when there is no crane during demolition; (2) How to change the angle of the flue from the converter span to the charging span during demolition; (3) How to control and reduce the overlap with production when dismantling the old flue and installing the new flue; (4) How to protect the flue and reduce flue collision when hoisting the new flue; (5) How to facilitate the charging span crane and truck crane to cooperate with the winch to lift the flue when hoisting the flue.

[0046] In view of the above difficulties, through the first three flue replacement operations, an operation method of arranging a winch for lifting the converter platform and tower and coordinating the platform with a truck crane was summarized as a safe and efficient replacement operation method for the vaporization cooling flue of a 120t converter.

[0047] Operation preparation and construction sequence: Installation measurement benchmark reservation: In order to make the converter center, flue oxygen gun mouth center and flue lower mouth center concentric. Before dismantling, reserve the center of the original flue, the center and elevation of the oxygen gun mouth, and return the center, level and elevation of the lower mouth of the horizontal flue to the columns and beams near the flue on the 23.5m platform. After the flue, flue lower mouth and oxygen gun mouth are installed in place, hang the plumb bob and steel wire to return the center of the converter to the 23.5m platform, compare the converter center with the original flue center line and oxygen gun center to see if there is any deviation, and then make adjustments. Hang a plumb line based on the oxygen gun center as the reference point, calibrate the oxygen gun mouth center and the furnace mouth section flue center. The closer the concentricity data of the two are, the more accurate the flue center positioning is.

[0048] The construction operation sequence of the demolition of the 120t converter gasification cooling flue is as follows: construction preparation → shutdown and hanging → dust cleaning → flue hanging point arrangement → installation and hanging of winch pulley block → tower three-story platform, insulation ceiling demolition → fourth-story, (fifth-story, sixth-story) platform beams and slab demolition → secondary dust removal hood demolition → separation of the movable smoke hood and its lifting mechanism → demolition of the movable smoke hood → demolition of the furnace mouth section flue → demolition of the main I section flue → demolition of the main II section flue → demolition of the final section flue;

[0049] Installation construction operation sequence of 120t converter vaporization cooling flue: install the non-metallic compensator between the evaporative cooler and the last section of the flue in place → hoist the last section of the flue → hoist the main section II flue → hoist the main section I flue → hoist the furnace mouth section flue → restore the furnace mouth section flue support beam → calibrate the oxygen gun mouth and the furnace mouth section flue center → calibrate each section of the flue and tighten the connecting bolts, support, suspension calibration, welding, etc. → install movable smoke hood → install insulation ceiling → install charging port, oxygen gun mouth → pipe fitting, pressure testing → install and restore the platform plates on each floor → unload waste materials, clean up the tower, and exit with "three cleanups".

[0050] Specific implementation steps of the operation method:

[0051] Layout of winch: Principles of winch layout: The winch is installed in a flat place without obstacles, so that the operator can clearly see the lifting equipment and communicate with the commander. The distance between the winch drum and the nearest guide pulley should be greater than 20 times the length of the drum. When the rope is wound around the two ends of the drum, the deflection angle of the wire rope is less than 5° to ensure that the rope is neatly arranged on the drum. When the rope is wound around the center of the drum, the center line of the drum and the rope should be perpendicular to each other. The winch must be set in a place that is easy to reinforce, and the winch must be firmly, solidly and steadily installed to prevent tilting or slipping when lifting heavy objects.

[0052] During the construction work, one converter was under maintenance, and the other converter next to it was in production. Due to the working conditions and geographical conditions, it was impossible to use the factory crane for direct construction work throughout the whole process. According to the site conditions and construction organization control and to reduce the impact on the normal production of the other converter next to it, the hoisting technology of the winch and 50t truck crane was adopted. A 50t truck crane was installed on the 9.1m platform of the converter to assist in the removal and installation of the flue. Its layout is as follows Figure 1 shown.

[0053] A 16t traction winch is arranged on the 9.1m platform, which is mainly used to pull the movable smoke hood and lift the furnace mouth section flue as the main force. At the same time, it cooperates with the 50t truck crane to send the smoke hood and the furnace mouth section flue to the bottom of the charging straddle crane for lifting.

[0054] After the winch is arranged, clean the accumulated dust and protectively remove the supporting beams before and after the flue of the furnace mouth section and the platform plates and small beams nearby, remove the beams and plates above the dustproof room, and use a 50t truck crane to remove the secondary dust removal hood.

[0055] Disassembly and installation of each section of flue and smoke hood: Disassembly and installation of movable smoke hood:

[0056] Since the distance between the movable smoke hood and the furnace mouth is 760mm, the height of the furnace shell after shaking flat is about 1200mm with the movable smoke hood, and the movable smoke hood cannot be moved out as a whole at the smelting position, the converter mouth needs to be turned to a horizontal lower position, and the movable smoke hood is suspended on all sides with 4 5t hand winches, separated from the movable smoke hood and its lifting mechanism (and the position of the lifting mechanism chain is recorded to facilitate the recovery of the movable skirt cover), and the 4 5t hand winches are synchronously loosened to place the movable smoke hood flat on the converter shell. Then, the movable smoke hood is pulled from the back of the furnace with the traction winch rope, the 50t truck is hung, and the 4 hand winch hooks are disconnected. Then the furnace is slowly rotated to cooperate, and the movable smoke hood is moved out, and the 50t truck crane slowly lifts it, untied the traction winch rope, and the 50t truck crane slowly lifts it out of the fire door in front of the furnace, and then placed on the 9.1m platform for charging, and the movable smoke hood is transported to the open space at the entrance of the molten iron under the furnace by a crane, and then transported away later. The installation method of the movable smoke hood is the same as the removal method, but the steps are reversed. Figure 2-Figure 4shown.

[0057] Dismantling and installation of the furnace mouth section flue: After the movable smoke hood is dismantled, the furnace mouth section flue is dismantled. First, the vaporization cooling ascending and descending pipes connected to the furnace mouth section flue are dismantled, and the corresponding numbers are numbered one by one for easy restoration later. Then, the 18.6m and 23.5m platforms and beams are dismantled, with the principle of being able to dismantle and install the furnace mouth section flue smoothly.

[0058] Weld δ=30mm on the oxygen gun nitrogen sealing platform beam and the side of the opposite platform beam; two 500×900 lifting ears are used as the main hoisting 32t pulley rope hanging points. The hanging point position is 2m below the connecting flange between the working section and the fixed section. The wire rope is "big" and tied to the wheel of the 32-ton pulley group. The lifting point of the 50t truck crane is on the outside of the ring pipe of the flue downcomer header of the furnace mouth section, close to the charging span.

[0059] Strength verification of wire rope at lifting point:

[0060]

[0061] Where: [Fg] is the allowable tension of the wire rope (kgf), The reduction factor to take into account the uneven load between the steel wires is For 6×37 wire rope K is the safety factor of the wire rope. Assuming that all loads are borne by the wire rope, and considering that the wire rope is not subjected to vertical force during the lifting process, the safety factor is calculated as 10. Fg is the total breaking force of the wire rope (kgf). The breaking force value of the wire rope can be found in the table. F is the actual force of the wire rope (kgf).

[0062]

[0063] According to the table, the nominal tensile strength of 6×37Φ43mm steel wire rope is 1700N / mm 2 Calculation shows that its breaking force is 118500kgf, which meets the use requirements.

[0064] Selection of winch system: Determination of winch model and its arrangement: The running rope is led out from the fixed pulley of the 2×4 pulley group, passes through two guide pulleys and is coiled on the winch drum.

[0065] The calculation formula of the winch's traction force S is:

[0066]

[0067] Where: f ais the guide pulley resistance coefficient, k is the number of guide pulleys, f is the pulley block resistance coefficient, and Q is the load. The 2×4 pulley block uses bronze bushings, and its f=1.04. The guide pulley also uses bronze bushings, and its f a =1.04.

[0068]

[0069] Therefore, the 5t winch can meet the use requirements. The selection of winch wire rope assumes that the safety factor of the winch wire rope is 6.

[0070] 6×2730.84=16385.04kgf≤29600kgf; therefore, the use of 21.5mm steel wire rope can meet the use requirements. (The nominal tensile strength of 6×37 steel wire rope is 170Kg / mm 2 Calculated, its breaking force is 29600kgf.)

[0071] After tying and tightening the main hoisting pulley group (4×4; 32t) and traction ropes of two load-bearing winches, loosen the furnace mouth section flue and the main I section flue and other connections, slowly lower it about 1m, use a hand-pulled hoist (falling chain) to tilt it backwards, lift it with a traction winch, and slowly pull it to the outside of the fire door in front of the furnace, so that the upper end of the flue falls on the furnace body (support ring), re-tie the main hoisting rope, use the crane to lift it, untie the hoisting point of the winch, disengage the crane hoisting point, and use the crane to lift it out to the designated position for placement. During construction, the furnace body can be appropriately rotated to cooperate with the winch. During dismantling, the furnace mouth is tilted 45° backwards to make room for hoisting. According to the situation of the lower flue, the furnace body is appropriately rotated to safely lift out the flue. After the hoisting is completed, attention should be paid to the restoration of various pipelines, platforms, etc. to ensure accuracy and success of the welding work at one time. The installation method of each section of the flue (movable smoke hood, furnace mouth section flue, main section I flue, main section II flue, and final section flue) is the same as the removal method, but the steps are reversed. See below for details. Figure 5-Figure 7 shown.

[0072] The operation method of dismantling and installing the main flue section I: Arrange an 8t load-bearing winch on the 33.8m platform, hang a set of pulleys (2#) under the 44.3m platform beam to dismantle and install the main flue section I, and use the 1# pulley group to complete it. Dismantling of the main flue section I: When dismantling this section of the flue, first use the main hoisting steel rope of the winch above the flue section I to fix its upper part, and use the winch steel rope above the furnace mouth section to fix its lower part. After the connection between the flue section I and the flue section II is removed, lower the flue; when the flue falls, use the 1# pulley group of the lower winch to adjust the direction of the flue to avoid hitting the pipes next to it. When the main flue section I descends to the furnace mouth, use the converter tilting furnace shell to move it, and then use the charging straddle crane to lift out each section of the flue, and then lift it to the molten iron pretreatment for recycling. The installation method of the main flue section I is the same as the dismantling method, but the steps are reversed.

[0073] The method of dismantling and installing the main section II flue is as follows: an 8t and a 5t load winch are arranged on the 44.3m platform, and a set of pulleys (3#, 4#) are hung on the ears under the beam of the 56.2m platform to dismantle and install the main section II flue, and the 2# pulley group is used to complete the dismantling. This section of the flue is located at a higher position, and the main hoisting steel rope of the winch (8t) directly above the section II flue is mainly used for dismantling. During the descent process, the other two winches assist in the descent. The dismantling method when the flue descends to the furnace mouth is the same as that of the section I flue. The installation method of the main section II flue is the same as the dismantling method, and the steps are reversed.

[0074] Dismantling and installation of the final flue: When dismantling the final flue, first use three 10t hand winches to move the flue to the flue opening (just above the main II flue), then use the top 8t winch system to hoist it out. During the descent of the flue, the other two winches assist in the descent. When the flue is lowered to the furnace opening, the dismantling method is the same as that of the II flue. The installation method of the final flue is the same as the dismantling method, but the steps are reversed.

[0075] The present invention provides a method for safely and efficiently dismantling and replacing a 120t converter vaporization cooling flue, which is a method for safely and efficiently replacing a 120t converter vaporization cooling flue in an original factory building. During the implementation process, safety risks are fully identified, and complete and detailed safety precautions are formulated and strictly implemented to ensure safety, efficiency and convenient operation. The 120t converter vaporization cooling flue (movable smoke hood, furnace mouth section flue, main I section flue, main II section flue, and end section flue) is replaced. During the flue replacement construction process, it is completed safely, efficiently, with high quality and quantity, saving maintenance costs and reducing the labor intensity of maintenance personnel, so as to better complete the steelmaking production technical indicators and create economic benefits, which has high value.

[0076] The five sections of the converter flue are all arranged in the converter span. There is only one 10-meter crane above the converter span, which cannot meet the lifting capacity of each section of the flue. How to replace the flue safely, efficiently, and with guaranteed quality is a difficult point in the construction operation. Figure 1 A 50t truck crane is installed on the 9.1m platform of the converter to assist in the removal and installation of the flue. After the hoist is arranged, the dust accumulation is cleaned and the support beams before and after the flue of the furnace mouth section and the platform plates and small beams nearby are removed in a protective manner. The beams and plates above the dustproof room are removed, and the secondary dust removal cover is removed by a 50t truck crane. Figure 2-Figure 4 Then use the traction winch rope to pull the movable smoke hood from the back of the furnace, hang it on the 50t truck, disengage the 4 hand-pulled hoist hooks, and then slowly rotate the furnace to cooperate, move out the movable smoke hood, slowly lift it up with the 50t truck crane, untie the traction winch rope, and slowly lift it out of the fire door in front of the furnace with the 50t truck crane, and then place it on the charging span 9.1m platform, and use the crane to transport the movable smoke hood to the open space at the entrance of the molten iron under the furnace, and then transport it away later. The installation method of the movable smoke hood is the same as the removal method, and the steps are reversed. Figure 5-Figure 7The hoisting method of each section of the flue (movable smoke hood, furnace section flue, main section I flue, main section II flue, and end section flue) is the same as the removal method, and the steps are reversed. Features: The present invention has the characteristics of low investment cost, easy implementation, reduced spare parts consumption, safe and efficient use during the process, etc.

Claims

1. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue, characterized in that: The method comprises dismantling a 120t converter vaporization cooling flue and installing a 120t converter vaporization cooling flue; The demolition of the 120t converter gasification cooling flue includes: construction preparation, furnace shutdown and signboard, dust cleaning, flue hanging point arrangement, installation and hanging of winch pulley block, tower three-story platform and insulation ceiling demolition, four-story or five-story or six-story platform beams and plates demolition, secondary dust removal hood demolition, separation of movable smoke hood and its lifting mechanism, demolition of movable smoke hood, demolition of furnace mouth section flue, demolition of main section I flue, demolition of main section II flue, and demolition of the final section flue; The installation of the 120t converter vaporization cooling flue includes, in sequence: installing the non-metallic compensator between the evaporative cooler and the last section of the flue, hoisting the last section of the flue, hoisting the main section II flue, hoisting the main section I flue, hoisting the furnace mouth section flue, restoring the furnace mouth section flue support beam, calibrating the center of the oxygen gun mouth and the furnace mouth section flue, calibrating each section of the flue and tightening the connecting bolts, calibrating and welding the supports and suspension, installing the movable smoke hood, installing the insulation ceiling, installing the charging port and oxygen gun mouth, piping and pressure testing, installing and restoring the platform plates on each floor, unloading the waste materials and cleaning the tower.

2. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1, characterized in that: In the layout of the winch: the winch is installed in a flat place without obstacles, the distance between the winch drum and the nearest guide pulley is greater than 20 times the length of the drum; when the rope is wound around both ends of the drum, the deflection angle of the wire rope is less than 5°; when the rope is wound around the center of the drum, the center line of the drum and the rope should be perpendicular to each other.

3. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1 or 2, characterized in that: During the arrangement and construction work of the winch, the hoisting technology combining the winch with a 50t truck crane was adopted; a 50t truck crane was arranged on the 9.1-meter platform of the converter to cooperate with the removal and installation of the flue.

4. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 3, characterized in that: At least one 16t traction winch is arranged on the 9.1m platform to pull the movable smoke hood and lift the furnace mouth section smoke duct as the main force; at the same time, cooperate with the 50t truck to lift the smoke hood and the furnace mouth section smoke duct to the bottom of the charging straddle car; After the winch is arranged, clean the accumulated dust and protectively remove the supporting beams before and after the flue of the furnace mouth section and the platform plates and small beams nearby, remove the beams and plates above the dustproof room, and use a 50t truck crane to remove the secondary dust hood.

5. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1, characterized in that: In the method, the removal and installation operation methods of the movable smoke hood are as follows: Turn the converter mouth to a horizontal lower position, use four 5t hand chain hoists to hang the movable smoke hood on all sides, detach the movable smoke hood and its lifting mechanism, and simultaneously loosen the four 5t hand chain hoists to place the movable smoke hood flat on the converter shell; then use the traction winch rope to pull the movable smoke hood from the back of the furnace, hang it on the 50t truck, disengage the four hand chain hoist hooks, and then slowly rotate the furnace to cooperate, move out the movable smoke hood, slowly lift it up with the 50t truck crane, untie the traction winch rope, and slowly lift it out of the fire door in front of the furnace with the 50t truck crane, and then place it on the charging span 9.1m platform, and use the crane to transport the movable smoke hood to the open space at the molten iron entrance under the furnace, and wait for it to be transported away later; The installation method of the movable smoke hood is the same as the removal method, but the steps are reversed.

6. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1 or 5, characterized in that: In the method, the removal and installation operation of the furnace mouth section flue is as follows: After the movable smoke hood is removed, the furnace mouth section flue begins to be removed. First, the vaporization cooling ascending and descending pipes connected to the furnace mouth section flue are removed, and they are numbered one by one to facilitate later restoration; then the 18.6m and 23.5m platforms and beams are removed; Two lifting ears are welded on the side of the oxygen lance nitrogen sealing platform beam and the opposite platform beam as the main winch 32t pulley rope hanging points. The hanging point is 2m below the connecting flange of the working section and the fixed section. It is tied to the 32-ton pulley group wheel with a φ43 steel wire rope. The 50t truck crane hanging point is on the outside of the ring pipe of the flue downcomer header of the furnace mouth section, close to the charging span.

7. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1, characterized in that: The main I section flue removal and installation operation method is as follows: Arrange at least one 8t load winch on the 33.8m platform, hang a set of pulley No. 2 on the lug under the 44.3m platform beam to dismantle and install the main I section flue, and use the No. 1 pulley set to complete the work; The main section I flue removal: when removing this section of flue, first use the main hoisting steel rope of the winch above the section I flue to fix its upper part, and use the winch steel rope above the furnace mouth section to fix its lower part. After the connection between the section I flue and the section II is removed, lower the flue; when the flue falls, use the No. 1 pulley block of the lower winch to adjust the direction of the flue; When the main I-section flue descends to the furnace mouth, the converter is used to tilt the furnace shell to move it, and then the charging straddle crane is used to lift out each section of the flue, and then hoisted to the molten iron pretreatment for recycling and disposal; The installation method of the main section I flue is the same as the removal method, with the steps being reversed.

8. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1, characterized in that: In the method, the removal and installation operation of the main II section flue is as follows: Arrange at least one 8t and at least one 5t load winch on the 44.3m platform, hang a set of pulleys on the lifting lugs under the 56.2m platform beam to dismantle and install the main II section flue, and use the No. 2 pulley block to complete the dismantling; use the 8t winch main hoisting rope just above the II section flue to dismantle, and the other two winches assist in the descent during the descent. The dismantling method when the flue is lowered to the furnace mouth is the same as that of the I section flue; The installation method of the main II section flue is the same as the removal method, with the steps being reversed.

9. A safe and efficient removal and replacement method for a 120t converter vaporization cooling flue according to claim 1, characterized in that: In the method, the method for removing and installing the last section of the flue is as follows: When dismantling the last section of the flue, first use three 10t hand hoists to move the flue to the flue mouth, just above the main section II flue, and then use the top 8t winch system to lift it out. During the descent of the flue, the other two winches assist in the descent. The dismantling method when the flue is lowered to the furnace mouth is the same as that of the section II flue. The installation method of the final flue section is the same as that of the removal, but the steps are reversed.

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