A method of hoisting a vaporizing flue

Abstract

This invention relates to the field of mechanical equipment installation technology, specifically to a method for hoisting a vaporization flue, comprising a base and a panel: the base is composed of two symmetrically arranged L-shaped aluminum alloy pieces, which are respectively installed on the structural base on both sides of the expansion joint; the base is equipped with anchor bolts, sliding rods, and temporary fixing bolts; the anchor bolts are used to securely connect the panel to the base; the sliding rods are used to limit the horizontal displacement direction of the panel and reserve deformation sliding allowance; the temporary fixing bolts are used for pre-positioning of the base during the construction phase; the panel is made of aluminum alloy with bolt holes on its surface, the bolt hole positions corresponding one-to-one with the anchor bolt positions on the base; after the panel and base are assembled, an expansion and contraction adjustment gap is reserved along the extension direction of the expansion joint; after construction, the cover plate is flush with the structural surface, the overall flatness of the floor slab is consistent, and the load-bearing capacity is high, making it less prone to deformation, thus meeting the needs of production and daily use.

Description

Technical Field

[0001] This invention relates to the field of mechanical equipment installation technology, specifically a method for hoisting a vaporization flue. Background Technology

[0002] Once the steel structure tower for steelmaking has been completed, the installation of the vaporization flue will face the following technical challenges: After the steel structure tower is enclosed, large hoisting equipment cannot enter the tower or reach the hoisting work surfaces on each floor, making it difficult to hoist each section of the vaporization flue into place in the forward direction; if the top or side steel structure of the steel structure tower is removed for hoisting, it will not only damage the structural integrity of the tower and increase the cost of construction machinery, but also prolong the construction period and affect the subsequent production progress.

[0003] While some existing technologies involve reverse hoisting or inverted installation, these are mostly limited to partial hoisting within enclosed factory spaces. They fail to consider the structural characteristics of steelmaking tower structures and lack a standardized inverted installation method that integrates pre-reserved installation holes, top hoisting frames, and winches. This makes it difficult to address the core requirement of accurately, safely, and efficiently positioning the vaporization flue after tower completion. Therefore, we propose a new method for installing vaporization flues. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this solution provides a method for the inverted installation and hoisting of vaporization flues that is suitable for the post-construction working conditions of steelmaking steel structure towers, requires no damage to the tower structure, and features high hoisting accuracy and strong safety.

[0005] This application provides a method for hoisting a vaporization flue: S1. Construction Preparation: Inspect the completed steel structure tower of the steelmaking plant to confirm that the strength and stability of the tower's steel structure and the size and location of the reserved gasification flue openings meet the design requirements. Verify that the dimensions of each section of the gasification flue components are suitable for the hoisting requirements. Prepare hoisting frame materials, winches, wire ropes, pulley blocks, hand chain hoists, and safety protection facilities, and complete equipment debugging. Among them, the gasification flue hoisting operation is completed before the converter installation and is carried out through the reserved gasification flue openings above the converter. S2. Installation of the hoisting frame: The hoisting frame is fabricated according to the reserved opening size of the vaporization flue, the maximum weight of a single section of the vaporization flue, and the structural characteristics of the top of the tower. The hoisting frame is made of welded steel sections and includes longitudinal and transverse beams, supporting columns, and diagonal braces. The center of the hoisting frame is coaxially aligned with the center of the reserved opening. The frame size is larger than the reserved opening size. The hoisting frame is fixed to the steel structure at the top of the tower by welding. Stiffening plates are installed at the connection points for reinforcement. The hoisting frame is put into use after passing the stress calculation and load test. S3. Layout of hoisting equipment: Two winches are symmetrically arranged on both sides of the middle of the hoisting frame. The two winches are symmetrically distributed with the center of the reserved hole. The winches are variable frequency winches with electromagnetic brakes. The rated tension is calculated to meet the dynamic load and unbalanced load requirements for the hoisting of the largest single section of the vaporization flue. Pulley blocks are installed below the middle of the hoisting frame and on both sides of the reserved hole. The wire rope of the winch passes through the pulley block and is connected at the end to a flexible sling that matches the vaporization flue component. The hoisting, lowering and braking functions of the winch are tested to confirm that the synchronous control accuracy meets the requirements. S4. Inverted Installation of Vaporization Flue: A top-down, section-by-section inverted installation method is adopted. First, the top section of the vaporization flue is hoisted, and then each section below is hoisted in sequence until all sections are in place. When hoisting a single section, the vaporization flue component is transported to the reserved opening at the top of the tower. The component is lifted by a winch and its posture is adjusted so that the center of the component is aligned with the center of the reserved opening before being lowered. After the current section of the component is in place, it is fixed with a temporary fixing device. After removing the hoisting equipment, the hoisting process is repeated to complete the hoisting, docking and fixing of the remaining sections of the vaporization flue in sequence.

[0006] Furthermore, in step S4, during the hoisting of the middle and lower flue, the position of the winch and pulley block is adjusted according to the hoisting height, and the hoisting operation is coordinated with the inspection and maintenance vehicle inside the tower.

[0007] Furthermore, in step S1, the minimum breaking strength of the wire rope used for hoisting preparation is not less than 5 times the hoisting load, thus meeting the hoisting safety factor requirements.

[0008] Furthermore, in step S1, the length and width of each segment of the vaporization flue are smaller than the corresponding dimensions of the reserved vaporization flue hole, and the reserved gap on one side is not less than 100mm.

[0009] Furthermore, in step S2, the longitudinal and transverse beams of the hoisting frame are welded from I-beams or H-beams, the height of the supporting columns is not less than 500mm, and the angle between the diagonal braces and the columns and beams is set to 45°-60°.

[0010] Furthermore, in step S2, the load test of the hoisting frame is carried out with a load weight of 1.25 times the maximum single-section hoisting weight, and the load holding time is not less than 30 minutes. After confirming that the frame has no deformation and the welded parts have no cracks, it is put into use.

[0011] Furthermore, in step S3, the synchronous control accuracy deviation of the two winches is no greater than 20mm, and the rated pulling force of a single winch is no less than 1.5 times the maximum single-section lifting weight.

[0012] Furthermore, in step S4, during the hoisting and lowering of a single section of vaporization flue, two traction ropes are set on each side of the component, and ground workers control the posture of the component to avoid collision with the steel structure of the tower or the edge of the reserved opening.

[0013] Furthermore, in step S4, after the current section of the vaporization flue is in place, at least four sets of symmetrically arranged temporary fixing plates are used to temporarily connect it to the upper component or tower steel structure. The load-bearing capacity of the temporary fixing device is not less than twice the weight of a single component.

[0014] Furthermore, after all the vaporization flues are hoisted and connected, all welds will be subjected to non-destructive testing. Only after the testing is passed will all temporary fixing devices be removed.

[0015] The technical solution provided in this application has at least the following technical effects or advantages: 1. This invention addresses the situation where the steel structure tower of a steelmaking plant has already been constructed. By utilizing the pre-reserved gasification flue holes at the top of the tower and employing a collaborative operation method of "top hoisting frame + winch", the gasification flue sections can be installed in reverse without dismantling the steel structure of the tower. This avoids damage to the tower structure, ensures the integrity and safety of the tower structure, and reduces the construction cost and time required for structural repair. 2. During the construction process of this invention, the safety of hoisting operations is ensured through stress calculation, load testing, trial hoisting inspection, and full-process monitoring. At the same time, the inverted construction method simplifies the hoisting process, reduces the amount of high-altitude work, improves construction efficiency, shortens the construction cycle, and reduces the labor intensity of construction personnel. 3. This invention is adaptable to vaporization flues and steelmaking steel structure towers of different specifications. It has strong versatility, a highly operable construction process, does not require complex large-scale equipment, has low investment costs, and is easy to promote and apply. It is suitable for the installation of vaporization flues after the completion of various steelmaking steel structure towers, and is especially suitable for reverse hoisting scenarios in enclosed spaces. Attached Figure Description

[0016] Figure 1 This is a segmented diagram of the vaporization flue in this application; Figure 2 This is a diagram of another section of the vaporization flue in this application; Figure 3 This is a partial schematic diagram of the steel structure tower for steelmaking in this application; Figure 4 This is a schematic diagram of the winch used in this application; Figure 5 This is a schematic diagram of the fixed frame of this application; Figure 6 A schematic diagram of the reserved vaporization flue hole for this application; Figure 7 This is a schematic diagram of the alignment plate for this application; Figure 8 This is a schematic diagram of the side sectional view of the alignment plate in this application.

[0017] In the diagram: 1-Steelmaking steel structure tower; 2-Wind machine; 3-Wire rope; 4-Pulley block; 5-Lifting frame; 51-Support leg; 6-Reserved opening for vaporization flue; 7-Hand chain hoist; 8-Alignment mechanism; 81-Fixed frame; 82-Double threaded screw; 83-Moving block; 84-Connecting support rod; 85-Alignment plate; 851-Positioning cavity; 852-Connecting spring; 853-Positioning plate; 86-Rotating gear; 87-Electric push rod; 88-Push frame; 89-Push rack; 9-Section 1; 91-Section 2; 93-Section 3; 94-Section 4; 95-Section 5; 96-Section 6; 97-Section 7. Detailed Implementation

[0018] This application discloses a method for hoisting a vaporization flue. The technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0019] To better understand the above technical solution, the following will provide a detailed explanation of the above technical solution in conjunction with the accompanying drawings and specific implementation methods.

[0020] Please see Figures 1 to 4 , Figure 1 The vaporization flue segmentation diagram of this invention shows that the vaporization flue is segmented according to the pre-reserved installation holes and the safe lifting weight, and the hoisting construction is carried out in sequence, with the hoisting sequence being segment 3-segment 4-segment 2-segment 1-segment 5-segment 6-segment 7.

[0021] Figure 2 This is a top view of the hoisting frame in an embodiment of the present invention. The top view clearly shows the structure of the horizontal beams, vertical beams and supporting columns of the hoisting frame, and clarifies that the frame is compatible with the reserved vaporization flue hole.

[0022] This embodiment is applied to a steel structure tower project in a steelmaking workshop with an annual steel production capacity of 3 million tons. The tower is a fully welded H-beam steel frame structure with a total height of 68m. The construction has been completed and accepted. A 4.2m × 3.8m installation hole for the vaporization flue gas duct is reserved above the converter installation position at the top of the tower. The vaporization flue gas duct being hoisted is the core section of the converter flue gas cooling system and also the most difficult part to install in the entire system. It is divided into 7 segmented components, with the largest single section weighing 27t and the largest single section length being 2.1m. The total length after assembly is 12m, and the designed installation position is 42m above the tower ground. This construction method is implemented before the converter equipment arrives on site and does not require modification to the existing steel structure of the tower. The specific construction steps are as follows: 1. Construction preparation stage A specialized work team was formed, including a hoisting supervisor, slingers, welders, and equipment commissioning personnel. Safety and technical briefings were conducted for all personnel, and the qualifications of special operations personnel were verified. First, a comprehensive inspection of the top load-bearing area of ​​the steel structure tower 1 was carried out: ultrasonic flaw detection was used to verify the quality of the steel structure welds around the reserved openings, and a stress testing instrument was used to verify the load-bearing capacity of the steel beams, confirming that the overall strength, stability, and overturning resistance coefficient of the tower met the design requirements. Simultaneously, the actual dimensions and center coordinates of the reserved vaporization flue opening 6 were checked. The measured length and width of the opening were 4220mm and 3810mm respectively, with a positional deviation of less than 5mm, meeting the installation requirements.

[0023] The factory certificates of conformity and dimensional inspection reports of the 7 sections of the vaporization flue were checked one by one to confirm that the length and width of all components were smaller than the corresponding dimensions of the reserved holes, and the minimum gap on one side was 105mm, which met the requirements for hoisting and passage.

[0024] Preparation for hoisting materials: The main frame is made of HM450×300 steel, equipped with two 5t variable frequency winches with electromagnetic brakes, and high-strength steel wire ropes (nominal tensile strength 1960MPa, minimum breaking strength 156kN, reaching 5.2 times the maximum hoisting load, meeting safety factor requirements) with 16mm diameter, 6×37+1 specification. It is also equipped with two sets of 32t-class 4×4 specification pulley blocks, four 10t hand-operated hoists, four sets of temporary fixing clamps, two 20m long nylon traction ropes, safety helmets, fall arrestors, safety warning tapes, and other protective facilities. Completion of on-site commissioning of all equipment: The hoisting, lowering, and braking functions of the winches 2 were tested under no-load conditions. The rotational flexibility of the pulley blocks 4 and the wear of the steel wire ropes 3 were fully inspected to confirm that all equipment was operating normally.

[0025] 2. Fabrication and installation of the top hoisting frame 5 Based on the reserved hole size, the maximum weight of a single flue section, and the layout of the steel beams at the top of the tower, the hoisting frame 5 was designed: The overall frame size is 12m×8m. The longitudinal and transverse beams and supporting columns are all welded from HM450×300 H-beams. The height of the supporting columns is set to 600mm. The diagonal braces are made of HM200×200 steel. The angle between the diagonal braces and the columns and transverse beams is controlled at 50°. After the frame is processed, all welds are subjected to magnetic particle testing to confirm that there are no cracks or porosity defects.

[0026] The hoisting frame 5 is hoisted to the installation position at the top of the tower. The position is adjusted so that the center of the frame is coaxially aligned with the center of the reserved hole, with the deviation controlled within 3mm. The bottom of the frame is fully welded to the steel beam of the steel structure at the top of the tower, and all connection parts are reinforced with 10mm thick stiffening plates.

[0027] After installation, a load test was conducted: the load was gradually increased to 33.75t (1.25 times the maximum single-section lifting weight) at the stress points of the frame and held for 30 minutes. During this period, displacement sensors were used to monitor the deformation of the frame in real time. Finally, it was confirmed that the maximum deformation of the frame was less than 2mm, there was no displacement, and there were no cracks in the welded parts. After passing the acceptance test, it was put into use.

[0028] 3. Installation of winch 2 and its supporting equipment Two 5t variable frequency winches 2 are symmetrically arranged on both sides of the upper part of the hoisting frame 5. The horizontal distance between the two winches 2 is 8m, and they are symmetrically distributed with the center of the reserved hole. The base of the winch 2 is made of 20mm thick steel plate and is fully welded to the steel structure beam of the tower. The calculated overturning safety factor is 2.8 and the slippage safety factor is 2.2, both of which meet the specifications.

[0029] Install one set of 32t-class 4×4 pulley blocks 4 on each side of the reserved hole below the middle of the hoisting frame 5. The pulley blocks 4 are connected to the frame by pins and are equipped with anti-detachment pin safety devices. Pass the wire rope 3 of the winch 2 through the pulley blocks 4 in sequence. The end of the wire rope 3 is connected to a flexible sling adapted to the flue hoisting point. The rated load of the sling is not less than 40t.

[0030] After the equipment is installed, online commissioning is carried out: two winches 2 are started synchronously and no-load lifting tests are conducted 3 times to verify the synchronous control accuracy, confirm that the lifting height deviation of the two winches 2 is not greater than 15mm, the braking response time is less than 0.5s, and the hoisting synchronization requirements are met.

[0031] 4. Install each section of the vaporization flue in reverse order. The construction sequence is "top-down, section-by-section inverted installation". First, the topmost section (section 1) of the flue is hoisted, followed by the sections 2 through 7 below, until all sections are in place. ① Before hoisting a single section, the vaporization flue component to be hoisted is transported to the reserved opening at the top of the tower by the construction elevator. The component number and hoisting point position are checked. Flexible slings are used to bind the symmetrical hoisting points at both ends of the component. A 20m long traction rope is attached to each side of the component and controlled by two ground workers.

[0032] ② Start winch 2 for trial lifting. Slowly lift the component 200mm and then hold it statically for 10 minutes to check the tension of the slings, the braking reliability of winch 2, and the amount of frame deformation. After confirming that there are no abnormalities, start the formal lifting.

[0033] ③ During the lifting process, ground workers adjust the posture of the component by pulling the guide rope, and the command personnel use a double theodolite to monitor the position of the component throughout the process, so that the center of the component is aligned with the center of the reserved hole. After the deviation is controlled within 5mm, the component is slowly lowered so that it passes smoothly through the reserved hole.

[0034] ④ After the component is lowered to the design elevation, fine-tune the horizontality and verticality of the component to ensure that the interface docking error with the upper installed component is no more than 2mm. After docking, use 4 sets of symmetrically arranged temporary fixing clamps to temporarily connect the current section to the upper component or tower steel structure. The bearing capacity of a single set of temporary fixing clamps is 15t, and the total bearing capacity reaches 2.2 times the weight of a single component. After confirming that it is firmly fixed, remove the lifting equipment.

[0035] ⑤ Repeat the above process to complete the hoisting, docking, and welding of the remaining 6 flue sections in sequence. For the hoisting of the lower 5th to 7th flue sections, when the hoisting height exceeds 40m, adjust the installation position of pulley block 4 to the steel beam at an elevation of 38m inside the tower, and coordinate with the 10t inspection and maintenance vehicle inside the tower to carry out the hoisting operation, thereby reducing the risk of swaying during long-distance hoisting.

[0036] After all seven sections of the vaporization flue were hoisted and connected, 100% ultrasonic non-destructive testing was carried out on all circumferential and longitudinal butt welds. After the tests were passed and the overall verticality and horizontality met the acceptance standards, all temporary fixing devices were removed step by step.

[0037] This embodiment, through the above-described construction method, eliminates the need to demolish any existing structure of the steelmaking tower 1. By utilizing the top hoisting frame 5 and the double winches 2 working together, the precise and safe inverted installation of all 7 sections of the vaporization flue was completed in just 7 working days. Compared with the traditional method of dismantling and modifying the tower structure for upright hoisting, the construction period is shortened by 60%, the construction cost is reduced by about 45%, the hoisting and docking accuracy is controlled within 2mm, and no safety hazards occurred throughout the process. It fully meets the equipment installation requirements for converter production and has good practicality and promotion value.

[0038] Example 2 Please see Figures 3 to 8 This embodiment is an optimized supplement to embodiment one. By adding an alignment mechanism 8 to the top hoisting frame 5, the positioning accuracy of the frame installation and the centering efficiency of the flue hoisting are further improved. It is suitable for construction scenarios where the position deviation of the reserved hole is strictly controlled and the wind speed conditions of the hoisting operation are unstable. The rest of the construction process and equipment parameters are consistent with embodiment one.

[0039] 1. Alignment Mechanism 8 Structural Design The bottom of the top hoisting frame 5 is equipped with four HM450×300 steel support legs 51, each 600mm high. Multiple support legs 51 are fixedly connected to each other by an alignment mechanism 8. The alignment mechanism 8 is used for automatic positioning during the installation of the hoisting frame 5 and for auxiliary alignment and temporary fixing during the hoisting of flue components. The specific structure is as follows: The alignment mechanism 8 includes an outer rectangular fixed frame 81. The four sides of the fixed frame 81 are fully welded to the inner sides of the four support legs 51. Each of the four sides of the fixed frame 81 has an independent receiving cavity. Each receiving cavity is rotatably connected to a bidirectional threaded screw 82 with a length adapted to the cavity through a bearing seat. On the outer side of the bidirectional threaded screw 82, two reverse threads are symmetrically connected to a moving block 83. The inner side of the fixed frame 81 has a strip-shaped moving opening that communicates with the receiving cavity. The moving block 83 slides through the moving opening and extends to the inner side of the fixed frame 81. One end of the moving block 83 located outside the moving opening is rotatably connected to a connecting support rod 84 through a hinge support.

[0040] The two connecting rods 84 corresponding to each bidirectional threaded screw 82 are hinged to each other and connected to the alignment plate 85. There are a total of 4 alignment plates 85, which correspond to the east, south, west and north directions of the reserved hole respectively. A 5mm thick rubber buffer pad is pasted on the side of the alignment plate 85 near the reserved hole to avoid scratching the anti-corrosion layer of the flue component.

[0041] Each alignment plate 85 is also provided with a positioning cavity 851 at the bottom. Inside the positioning cavity 851, 6 sets of connecting springs 852 with a stiffness coefficient of 20N / mm are evenly fixedly installed along the length direction. The bottom of the multiple sets of connecting springs 852 are fixedly connected to a positioning plate 853. The positioning plate 853 slides through the bottom of the positioning cavity 851. In its natural state, the positioning plate 853 protrudes 20mm from the bottom of the alignment plate 85.

[0042] The bidirectional threaded screw 82 is fixedly sleeved with a rotating gear 86 on the outer side of the receiving cavity near the support leg 51. A motorized electric push rod 87 is fixedly installed at the bottom of the top hoisting frame 5. A rectangular push frame 88 is fixedly connected to the bottom of the electric push rod 87. A push rack 89 is vertically fixedly connected to the four corners of the bottom of the push frame 88. The push rack 89 is meshed with the rotating gear 86 at the corresponding position. When the electric push rod 87 extends or retracts, it can synchronously drive the four bidirectional threaded screws 82 to rotate through rack and gear transmission.

[0043] The alignment mechanism 8 in this embodiment can achieve dual functions, and the specific implementation process is as follows: ① Installation and positioning function of hoisting frame 5: After the hoisting frame 5 is hoisted to the top of the tower and initially aligned, the synchronous electric push rod 87 drives the push frame 88 to move downwards. Through the meshing transmission of the rack 89 and the rotating gear 86, the four double-sided threaded screws 82 are driven to rotate synchronously, causing the two moving blocks 83 on each screw to move towards each other, driving the four connecting support rods 84 to push the alignment plate 85 towards the center of the reserved hole; during the movement of the alignment plate 85, the bottom protruding positioning plate 853 first contacts the outer plane of the reserved hole at the top of the tower, and as the alignment plate moves, the positioning plate 85 moves towards the center of the reserved hole. As the positioning plate 85 continues to move, the positioning plate 853 is compressed by the plane and the connecting spring 852 retracts into the positioning cavity 851. When the positioning plate 85 moves to the edge of the reserved hole, the positioning plate 853 loses its plane support and pops out under the elastic force of the connecting spring 852 and fits against the inner side wall of the reserved hole. At this time, the four positioning plates 85 are respectively locked at the four side walls of the reserved hole, automatically completing the coaxial calibration between the center of the hoisting frame 5 and the center of the reserved hole. Then the frame and the tower steel beam can be welded and fixed, greatly shortening the time for manual calibration and alignment.

[0044] ② Auxiliary alignment and temporary fixing function for flue hoisting: During the lowering of a single flue component through the reserved hole, when the top of the component approaches the height of the alignment mechanism 8, the stroke of the electric push rod 87 is adjusted synchronously according to the component's posture, controlling the opening and closing dimensions of the four alignment plates 85 to guide and correct any misaligned components, so that the center of the component is quickly aligned with the design installation center, and to prevent the component from swinging and scraping against the steel structure around the hole; after the component is adjusted to the design elevation and the interface is connected, the alignment plates 85 are controlled to clamp the outer wall of the component inward, which can serve as a supplementary constraint for temporary fixing, and together with the temporary fixing clamps, they bear the load, further improving the safety of high-altitude docking operations. After the interface welding is completed, the alignment plates 85 are controlled to open again to prepare for the hoisting operation of the next component.

[0045] 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.

[0046] The above description is merely a preferred embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present application, based on the technical solution and concept of the present application, should be covered within the scope of protection of the present application.

Claims

1. A method for hoisting a vaporization flue, characterized in that: S1. Construction Preparation: Inspect the completed steel structure tower of the steelmaking plant to confirm that the strength and stability of the tower's steel structure and the size and location of the reserved gasification flue openings meet the design requirements. Verify that the dimensions of each section of the gasification flue components are suitable for the hoisting requirements. Prepare hoisting frame materials, winches, wire ropes, pulley blocks, hand chain hoists, and safety protection facilities, and complete equipment debugging. Among them, the gasification flue hoisting operation is completed before the converter installation and is carried out through the reserved gasification flue openings above the converter. S2. Installation of the hoisting frame: The hoisting frame is fabricated according to the reserved opening size of the vaporization flue, the maximum weight of a single section of the vaporization flue, and the structural characteristics of the top of the tower. The hoisting frame is made of welded steel sections and includes longitudinal and transverse beams, supporting columns, and diagonal braces. The center of the hoisting frame is coaxially aligned with the center of the reserved opening. The frame size is larger than the reserved opening size. The hoisting frame is fixed to the steel structure at the top of the tower by welding. Stiffening plates are installed at the connection points for reinforcement. The hoisting frame is put into use after passing the stress calculation and load test. S3. Layout of hoisting equipment: Two winches are symmetrically arranged on both sides of the middle of the hoisting frame. The two winches are symmetrically distributed with the center of the reserved hole. The winches are variable frequency winches with electromagnetic brakes. The rated tension is calculated to meet the dynamic load and unbalanced load requirements for the hoisting of the largest single section of the vaporization flue. Pulley blocks are installed below the middle of the hoisting frame and on both sides of the reserved hole. The wire rope of the winch passes through the pulley block and is connected at the end to a flexible sling that matches the vaporization flue component. The hoisting, lowering and braking functions of the winch are tested to confirm that the synchronous control accuracy meets the requirements. S4. Inverted Installation of Vaporization Flue: A top-down, section-by-section inverted installation method is adopted. First, the top section of the vaporization flue is hoisted, and then each section below is hoisted in sequence until all sections are in place. When hoisting a single section, the vaporization flue component is transported to the reserved opening at the top of the tower. The component is lifted by a winch and its posture is adjusted so that the center of the component is aligned with the center of the reserved opening before being lowered. After the current section of the component is in place, it is fixed with a temporary fixing device. After removing the hoisting equipment, the hoisting process is repeated to complete the hoisting, docking and fixing of the remaining sections of the vaporization flue in sequence.

2. A method of hoisting a vaporizing flue according to claim 1, characterized in that, In step S4, when hoisting the middle and lower flue, the position of the winch and pulley block is adjusted according to the hoisting height, and the hoisting operation is coordinated with the inspection and maintenance vehicle inside the tower.

3. A method of hoisting a vaporizing flue according to claim 1, characterized in that, In step S1, the minimum breaking strength of the wire rope used for hoisting preparation shall not be less than 5 times the hoisting load, thus meeting the hoisting safety factor requirements.

4. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S1, the length and width of each segment of the vaporization flue are smaller than the corresponding dimensions of the reserved vaporization flue hole, and the reserved gap on one side is not less than 100mm.

5. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S2, the longitudinal and transverse beams of the hoisting frame are welded from I-beams or H-beams, the height of the supporting columns is not less than 500mm, and the angle between the diagonal braces and the columns and beams is set to 45°-60°.

6. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S2, the load test of the hoisting frame is carried out with a load weight of 1.25 times the maximum single-section hoisting weight, and the load holding time is not less than 30 minutes. After confirming that the frame has no deformation and the welded parts have no cracks, it is put into use.

7. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S3, the synchronous control accuracy deviation of the two winches shall not exceed 20mm, and the rated pulling force of a single winch shall not be less than 1.5 times the maximum single-section lifting weight.

8. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S4, during the hoisting and lowering of a single vaporization flue section, two traction ropes are set on each side of the component, and ground workers control the posture of the component to avoid collision with the steel structure of the tower or the edge of the reserved opening.

9. The method for hoisting a vaporization flue according to claim 1, characterized in that, In step S4, after the current section of the vaporization flue is in place, at least four sets of symmetrically arranged temporary fixing plates are used to temporarily connect with the upper components or the tower steel structure. The load-bearing capacity of the temporary fixing device is not less than twice the weight of a single component.

10. A method for hoisting a vaporization flue according to claim 9, characterized in that, After all the vaporization flues are hoisted and connected, non-destructive testing is carried out on all welds. Only after the testing is passed can all temporary fixing devices be removed.

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