A hoisting construction method for high-level platform large equipment of a converter steelmaking plant

Abstract

The present application belongs to the technical field of heavy equipment installation and construction in metallurgical engineering, and particularly relates to a hoisting construction method for large equipment of a high platform in a converter steelmaking workshop, characterized by the following steps: Step 1, pre-hoisting reinforcement and tooling prefabrication installation construction; Step 2, vertical hoisting of a bridge crane to an intermediate transition station; Step 3, first-stage pulley block cross-column force transfer; Step 4, second-stage pulley block lifting to a high installation platform; Step 5, equipment disengagement from a bracket and precise installation; and Step 6, tooling and reinforcement system dismantling and roof restoration. Compared with the prior art, the present application has the beneficial effect of greatly reducing roof modification work quantity, relying on a built-in bridge crane in the workshop + double-stage pulley block force transfer reverse installation process, without the need for rental of high-cost caterpillar cranes and automobile cranes, saving off-site crane platform shifts, entry and exit costs, greatly reducing roof restoration labor and material costs, and reducing comprehensive construction cost by more than 25%.

Description

Technical Field

[0001] This invention belongs to the field of heavy equipment installation and construction technology in metallurgical engineering, specifically relating to a hoisting and construction method for large equipment on a high-level platform in a converter steelmaking workshop. Background Technology

[0002] Currently, converter steelmaking production lines require a large number of heavy-duty, large-size core process equipment, including steam drums, waste heat flues, gravity dust collectors, deaerators, overflow venturi tubes, secondary venturi tubes, and double-stage cyclone dehydrators. These devices typically weigh 30-50 tons, and their installation elevations are mostly concentrated on the +45m to +60m high steel platform of the plant. When the main steel structure and roof enclosure of a newly built converter plant are not enclosed, the industry standard is to use crawler cranes, truck cranes, and workshop bridge cranes for installation. The common traditional installation sequence is: furnace body → waste heat flue → dust removal equipment → steam drum, with open construction space and unobstructed hoisting paths.

[0003] However, for existing or renovated old converter steelmaking workshops, the main steel columns, roof beams, pergolas, purlins, color-coated steel sheet cladding, and surrounding ancillary structures of the plant have all been completed. If traditional large off-site cranes are used to lift heavy equipment at high positions, the following significant technical drawbacks exist: 1. Extremely high safety risks during roof demolition and alteration: Crawler crane and truck crane operations require the removal of large areas of the plant's roof beams, purlins, and roof panels. High-altitude, near-edge hot work and large-scale demolition operations greatly increase the risk of falling objects, localized instability of the steel structure, and fires. 2. Significantly increased construction costs: The cost of transporting and renting large crawler cranes and truck cranes is exorbitant; the large roof... 1. After demolition, secondary restoration is required, incurring additional costs for roof waterproofing, color steel panels, purlins, and labor, increasing the overall cost by more than 30%; 2. The factory structure is prone to permanent damage: The original steel structure design of the old factory did not consider the additional vertical and horizontal loads generated by the lifting load of the off-site crane. Large-area openings and demolition of the roof will reduce the overall rigidity of the factory, and the lifting load can easily cause permanent deformation of the steel columns and main roof beams; 3. The construction period is extended: The three processes of roof demolition, hoisting, and roof restoration are carried out in an interleaved manner, extending the overall construction period by 15 to 25 days; Demolition of the roof will also damage the original insulation and waterproofing structure of the factory, making it very easy for roof leakage defects to occur later.

[0004] Current indoor hoisting technology relies solely on single-point vertical lifting by workshop bridge cranes. Constrained by the maximum span of the bridge crane's trolley and gantry, it cannot directly transport equipment to high-level installation points deep within the plant. Individual winch pulley hoisting lacks intermediate transition bearing positions, resulting in long-distance, suspended equipment transport. This leads to easy displacement of the cylinder, damage to the anti-corrosion layer and weld bevels, and insufficient safety redundancy in the hoisting of large-tonnage equipment. Furthermore, there is a lack of complete sets of reinforcement, transition tooling, and standardized segmented relocation procedures. For example, in the converter workshop, the steam drum installation is 12m long, weighs 38t, and is designed for an installation height of +54m. Existing 32 / 5t bridge cranes cannot reach the installation point directly across multiple steel columns using only one crane. Currently, the industry lacks a standardized construction method that integrates steel structure reinforcement, intermediate transition bearing, equipment protection, and multi-segment pulley relay transport. Summary of the Invention

[0005] The purpose of this invention is to provide a method for hoisting large equipment on a high-level platform in a converter steelmaking workshop. This method overcomes the shortcomings of existing technologies, eliminating the need for large-scale demolition of the factory roof. It utilizes the existing bridge crane and double-section winch pulley system for relay-style installation, along with a dedicated steel structure reinforcement system, a mid-level temporary transition support platform, and protective brackets for cylindrical equipment. This allows for the smooth, layered, segmented, and cross-row transfer of 30-50 ton heavy equipment to high-level installation locations, reducing the risks of high-altitude operations and saving on the costs of renting large lifting machinery and repairing the roof. The entire system is reusable and adaptable to the installation of all high-level cylindrical metallurgical equipment in the workshop. The hoisting force is balanced, with sufficient safety redundancy, standardized construction procedures, and controllable equipment positioning accuracy.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for hoisting large equipment on a high-level platform in a converter steelmaking workshop, utilizing a bridge crane and a temporary transition support platform, employs eight sets of pulley blocks to transfer the large equipment from the ground to the high-level platform. The method includes the following construction steps: Step 1: Pre-hoisting reinforcement and prefabrication installation of tools; installation of cross-bracing reinforcement members within the range of columns 201-203 of column 1 / D2-E in the factory building; welding of thickened reinforcing plates to the roof pulley suspension points; erection of a temporary transition bearing platform at +49m elevation and completion of rated load test; prefabrication of hoisting brackets; assembly of winches and eight sets of pulley blocks on site and completion of tensile load test; stable placement of the large equipment to be installed on the bracket panel, and use flexible strapping to limit and fix the equipment. Step 2: The bridge crane vertically lifts the equipment to the intermediate transition position. The bridge crane hooks the four corner lugs of the bracket and lifts the large equipment and bracket assembly vertically from the ±0m ground. It crosses the platforms of each floor of the factory building to the temporary transition platform at the +49m elevation. The hook is slowly lowered to place the assembly smoothly on the temporary platform, completing the first transfer. Step 3: The first section of the pulley block is used for cross-column relay lateral transfer. Start the +38m platform winch to pull the first group of four pulley blocks of steel columns 201-202 in column DE. The lower hook of the pulley block is connected to the bracket lifting lug. Simultaneously and slowly wind up the rope to lift the bracket assembly from the temporary platform of steel column 201 to the area of ​​steel column 202 in column 1 / D2-E, thus completing the cross-column relay transfer. Step 4: The second pulley block is raised to the high-level installation platform. The winch is switched to pull the wire rope to the second group of four pulley blocks of steel columns 202-203 in column 1 / D2-E. The winch synchronously and uniformly winds up the rope to raise the large equipment. The entire bracket is raised to the design installation elevation platform height of +54m. It is then moved laterally to the temporary fixed position of column 202. Step 5: The equipment is detached from the bracket and precisely positioned for installation. The bottom of the bracket is temporarily fixed by spot welding to the pre-embedded plate of the +54m platform. The flexible binding straps between the equipment and the bracket are removed. The connection points between the bracket lifting lugs and the rigging are cut using gas cutting to separate the large equipment from the lifting bracket. The pulley block above the 203 steel column is activated to slowly and laterally move the cylindrical equipment to the designed installation support position of the 203 steel column. Four hydraulic jacks are used to simultaneously lift the large equipment. The adjusting pads at the fixed end of the support and the movable roller assembly at the floating end are adjusted. After the cylinder level is checked with a level and meets the design tolerance, the hydraulic jacks are removed and all connecting bolts of the support are tightened. Step 6: Dismantle the tooling and reinforcement system and restore the roof. After the large equipment installation is accepted, dismantle the pulley block, winch, hoisting bracket, and +49m temporary transition platform in sequence; dismantle the steel column reinforcement diagonal tie rods of the DE column; only dismantle small sections of roof panels at the pulley lifting points. After the hoisting operation is completed, restore the roof panels, waterproofing and enclosure structure; the entire set of tooling is reused for the relocation construction of other large equipment in the workshop.

[0007] After the steel structure reinforcement and tooling prefabrication and installation in step 1 are completed, the non-destructive testing of the reinforcement welds and the deflection deformation of the steel columns are completed; the temporary transition platform, winch, and pulley block are all tested and accepted under 1.25 times the rated load, and hoisting operations can only be carried out after all test items are qualified.

[0008] When the equipment is detached from the bracket in step 5, protective measures should be taken throughout the gas cutting operation to avoid damaging the anti-corrosion layer of the equipment cylinder and the welding bevel.

[0009] The entire construction process does not require the removal of large areas of the factory's roof beams, purlins, and color-coated steel sheet enclosure structure; only small sections of roof panels at the pulley suspension points need to be removed.

[0010] The tooling includes a reinforced plant structure, a temporary transition support platform, brackets, and a pulley system. The reinforced plant structure is located in the area of ​​steel columns 201-203 in columns 1 / D2-E of the plant, and includes cross-bracing rods for the steel columns, column joint clamps, and roof suspension point reinforcement plates. Cross-bracing rods are installed between the steel columns in columns D, 1 / D2, and E, with both ends of the rods secured to the flanges of the steel columns by clamp bolts. Thickened reinforcement plates are welded at the +61m roof pulley suspension point. The temporary transition support platform is built at the +49m elevation platform of the plant, at the equipment hoisting holes of steel columns 201-202 in columns CD. It is supported by multiple I-beam columns for the lower main beam, and the platform panel is made of anti-slip thickened steel plate with high protective features around the perimeter. The railing; the bracket is a flat load-bearing structure, with lifting lugs with through holes welded to the four corners of the bracket panel, and multiple vertical support ribs set at the bottom of the bracket. The cylindrical equipment to be lifted is placed on the bracket panel and fixed with flexible straps; the pulley block transfer system includes a workshop bridge crane, a winch, and two sets of eight pulley blocks with rated loads; the safety factor of the bridge crane's rated load is 1.25 times; the winch is fixedly installed on the +38m low-level fixed platform of the factory building; the first set of four pulley blocks is arranged between columns 201-202 of column DE, and the second set of four pulley blocks is arranged at the roof lifting point above the +54m elevation of columns 202-203 of column 1 / D2-E. The lower hook of the pulley block is connected to the lifting lugs at the four corners of the bracket through steel wire rope slings.

[0011] The rated safe lifting weight of the bridge crane is suitable for the overall lifting operation of large cylindrical equipment such as steam drums.

[0012] The large cylindrical equipment of the steam drum type is any one of the following: steam drum, waste heat flue, deaerator, gravity dust collector, overflow venturi tube, secondary venturi tube, or double-stage cyclone dehydrator.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly reduces the amount of roof demolition and alteration work, lowering safety and construction cost risks. This invention utilizes a bridge crane built into the factory building and a double-section pulley system for relay installation, removing only small sections of roof panels at the lifting points, eliminating the need for large-scale demolition of roof beams, purlins, and color-coated steel sheet cladding; reducing high-altitude hot work and edge demolition work by more than 85%, thus preventing potential hazards such as falling objects, structural instability, and fire caused by roof demolition and alteration; eliminating the need to rent expensive crawler cranes and truck cranes, saving on off-site crane shifts and access costs, while also significantly reducing labor and material costs for roof repair, resulting in an overall construction cost reduction of more than 25%. 2. A complete set of reinforcement and transition tooling is used, ensuring high hoisting stability and comprehensive equipment protection. The supporting steel column cross reinforcement system evenly distributes the vertical and horizontal concentrated loads generated by multi-segment hoisting, avoiding permanent bending deformation of the original steel structure of the old factory building; the +49m temporary transition platform provides a reliable mid-level load-bearing position, enabling step-by-step transfer and smooth hook changing, and preventing long-distance drift of the equipment while it is suspended in the air; the special bracket isolates the slings from the cylindrical equipment, and the flexible binding limit prevents the cylindrical equipment from being bumped and scratched, fully protecting the factory anti-corrosion layer and welding bevels of the equipment, reducing equipment repair costs; 3. Layered and segmented relay transfer: Overcoming the limitations of the travel span of bridge cranes, the relay transfer process of two independent sections with four sets of 20t pulley blocks solves the industry pain point that the travel limits of a single bridge crane's trolley and trolley cannot reach the +54m high installation point deep in the factory. The eight sets of pulleys synchronously distribute the 38t equipment load evenly, with a rated load of 20t for each pulley. The multi-pulley collaboration provides sufficient safety redundancy, and the equipment posture is controllable during the hoisting process with no risk of overturning. 4. High versatility; the tooling can be reused for all large metallurgical equipment in the workshop. This hoisting device and standardized construction method are not limited to steam drum installation; they can be directly adapted to the inverted installation of all high-level, large-tonnage cylindrical equipment such as waste heat flues, various dust collectors, deaerators, and venturi tubes in the converter workshop. The reinforcing rods, hoisting brackets, and winch pulley system are all detachable and reusable. One set of equipment covers multiple equipment installation procedures in the entire workshop, improving overall construction efficiency by 40%. 5. Standardized construction procedures ensure precise and controllable equipment installation quality. The standardized step-by-step reverse installation process is adopted, which includes "ground prefabrication of tooling → bridge-type vertical lifting → first-section pulley cross-column transfer → second-section pulley lifting to a higher position → jack fine-tuning and positioning". Each process is subject to multiple acceptance nodes, including load testing, weld flaw detection, deflection detection, and levelness verification. The load, displacement, and attitude are fully controllable throughout the hoisting process, and the equipment positioning elevation and level accuracy fully meet the tolerance requirements of the metallurgical heavy equipment installation specifications. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the factory building reinforcement structure in the tooling of an embodiment of the present invention; Figure 2 This is a schematic diagram of the temporary transition bearing platform structure in the tooling of an embodiment of the present invention; Figure 3 This is a schematic diagram of the bracket structure in the tooling of an embodiment of the present invention; Figure 4 This is a schematic diagram of the process of lifting a steam drum to a temporary platform using a bridge crane in an embodiment of the present invention. The lifting operation begins. Figure 5 This is a schematic diagram of the first section of the pulley block relay transfer process for the steam drum in an embodiment of the present invention, showing the middle stage of hoisting; Figure 6This is a schematic diagram of the second pulley block lifting the steam drum to the +54m installation platform in an embodiment of the present invention, indicating the completion of the hoisting. In the diagram: 1-Steel column D of the factory building; 2-Steel column 1 / D2 of the factory building; 3-Steel column E of the factory building; 4-Crossing diagonal bracing rod for steel columns; 5-Column node clamp; 6-Roof suspension point reinforcement plate; 7-+49m temporary transition platform; 8-Platform support I-beam column; 9-Bracket; 10-Bracket lifting lug; 11-Flexible binding strap; 12-Steam drum body; 13-32 / 5t bridge crane; 14-75hp winch; 15-20t pulley block; 16-+38m low-level fixed platform; 17-Hydraulic jack; 18-Steam drum installation support. Detailed Implementation

[0015] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the specific embodiments used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some embodiments of the present invention. For those skilled in the art, other specific embodiments can be obtained based on these specific embodiments without creative effort.

[0017] See Figure 1-6 This is an operational schematic diagram of an embodiment of the hoisting construction method for large equipment on a high-level platform in a converter steelmaking workshop according to the present invention. Taking a modified converter steelmaking workshop as an example, the steel structure and roof enclosure of the workshop are all completed. The steam drum equipment is 12m long and weighs 38t. The design installation elevation is +54m. The workshop has a built-in 32 / 5t bridge crane. The low-level platform at +38m can be used to arrange hoisting equipment. The steel columns 201-203 in column DE are the steam drum hoisting operation area.

[0018] Before operation, arrange for the reinforcement of the factory structure, such as... Figure 1 As shown, the temporary transition support platform is as follows: Figure 2 As shown, the bracket is as follows Figure 3 The pulley block transfer system shown includes: The reinforced structure of the factory building is located in the work area of ​​steel columns 201-203 in columns 1 / D2-E of the factory building, including steel columns 1 in column D, steel columns 2 in columns 1 / D2, and steel columns 3 in column E. Components include cross-bracing rods 4, column joint clamps 5, and roof suspension point reinforcement plates 6. Cross-bracing rods are installed between the longitudinal steel columns in columns D, 1 / D2, and E, and between steel columns 201 / 202 / 203. All rods are secured to the column flanges at both ends with fully enclosed clamps and high-strength bolts. Thick steel plates are welded to the pre-set pulley blocks on the +61m roof beam of the factory building as reinforcement plates to distribute the concentrated load during hoisting and prevent local yielding and bending deformation of the roof beam. The overall structure of the reinforcement system is as follows: Figure 1 As shown.

[0019] The temporary transition platform is built at the +49m elevation platform of the factory building, at the location of the reserved equipment hoisting holes in the steel columns 201-202 of column CD. The +49m temporary transition platform 7 is a box-shaped structure. The bottom of the platform is supported by multiple load-bearing H-beam columns 8 on the main beam of the lower +38m platform, and the columns are fully welded to the main beam. The top surface of the platform is covered with thickened anti-slip patterned steel plates, and a 1.2m high safety guardrail is continuously erected around the platform. As an intermediate transition bearing position after the bridge crane lifts the equipment, it supports the equipment and bracket assembly, realizing the hook change conversion of the lifting, pulley relay transfer process. The platform structure is shown in [details omitted]. Figure 2 .

[0020] The bracket 9 is a flat-plate load-bearing fixture, suitable not only for steam drums but also for various high-level cylindrical heavy equipment in converter steelmaking workshops, such as waste heat flues, deaerators, gravity dust collectors, overflow venturi tubes, secondary venturi tubes, and double-stage cyclone dehydrators. The bracket 9 features symmetrically welded lifting lugs 10 with circular lifting holes at its four corners. Multiple vertical support ribs are welded at equal intervals at the bottom of the bracket 9 to enhance overall rigidity. The cylindrical equipment is placed on the bracket 9 panel and rigidly secured using flexible strapping 11. During the entire lifting process, the slings are only connected to the lifting lugs 10; the steam drum body 12 does not directly contact the wire rope slings, preventing damage to the anti-corrosion layer and weld bevels. The bracket can be transported synchronously with the equipment and can be disassembled after the equipment is in place. The bracket structure is as follows: Figure 3 As shown.

[0021] The pulley block transfer system includes the workshop's existing bridge crane, a 75-horsepower winch 14, and two sets of independent four 20t pulley blocks 15. The bridge crane is the original 32 / 5t bridge crane 13 in the factory. The lifting load safety factor is taken as 1.25 times the standard requirement, and the rated safe lifting weight is 40t, which meets the overall lifting requirements of 38t steam drum equipment. It is responsible for vertically lifting the equipment + bracket assembly from ±0m ground to +49m temporary transition platform. The winch is a 75-horsepower winch 14, which is rigidly fixed to the factory building +38m low-level fixed platform 16, serving as the unified traction power source for the entire pulley block. Relay pulley system: A total of eight 20t pulley systems (15 sets) are configured, arranged independently in two relay sections. The first pulley block (four blocks in total, 1#-4#): installed between steel columns 201-202 and elevations +49m-+61m in column DE, is responsible for laterally transporting the bracket assembly on the temporary platform to the area of ​​steel column 202; The second pulley system (4 sets in total, 5#-8#): installed on the steel columns 202~203 of column 1 / D2-E, and the roof lifting point above the +54m installation elevation, responsible for lifting the equipment to the +54m design installation platform and moving it laterally to the 203 steel column mounting position; each pulley system consists of two pulleys, one fixed pulley located on the upper part of the steel structure of the factory building and the other a movable pulley located on the lower part of the steel structure of the factory building).

[0022] All pulley blocks are fixed to the roof reinforcement suspension points of the steel structure reinforcement system. The lower hooks are connected to the bracket lifting lugs 10 at the four corners via flexible binding straps 11 (steel wire rope slings). Multiple pulley blocks are synchronously stressed and the lifting load is evenly distributed. See Figure 4 .

[0023] This invention utilizes a bridge crane and a temporary transition support platform, employing eight sets of pulley blocks to transfer large equipment from the ground to a high-level platform, and includes the following construction steps: Step 1: Pre-lifting reinforcement and tooling prefabrication and installation: 1.1 Steel structure reinforcement construction: Before the equipment hoisting operation, all steel columns 201-203 of column DE of the factory building shall be reinforced with cross diagonal bracing members, and all pulley blocks on the roof shall be welded with thickened reinforcing plates. After the reinforcement construction is completed, non-destructive testing of welds and deflection deformation testing of steel structure shall be carried out. Only after all test indicators are qualified can the next process be carried out. 1.2 Temporary transition platform construction: A temporary load-bearing platform was welded and fabricated at the locations of holes 201 to 202 in column CD at elevation +49m. The I-beam support columns were fully welded and fixed to the main beam of the platform, and protective railings were erected around the platform. After the platform was completed, a test load of 1.25 times the rated load was applied to test the platform's load-bearing capacity and deformation. 1.3 Prefabrication of brackets and assembly of lifting equipment: special lifting brackets are processed according to the outer dimensions of the steam drum, four corner lifting lugs are welded, and flexible protective strapping is provided; a 75 horsepower winch and eight sets of 20t pulley blocks are assembled on site, and traction steel wire ropes are threaded through them. Tensile load flaw detection tests are carried out on the winch, pulleys and steel wire ropes. 1.4 Equipment fixing and limiting: The steam drum is steadily hoisted and placed in the center area of ​​the bracket panel, and the steam drum body is rigidly fixed to the bracket using flexible strapping to prevent the body from sliding or rolling during the transfer process.

[0024] Step 2: The bridge crane vertically lifts the crane to the intermediate transition position. 2.1 Using the main hook of the workshop's 32 / 5t bridge crane, hook the four corner lugs of the bracket to vertically lift the steam drum and bracket assembly from the ±0m ground level, across the various floors of the factory building, to above the temporary transition platform at +49m elevation. Slowly and evenly lower the hook to place the assembly smoothly onto the temporary platform, completing the first transfer. See the process diagram below. Figure 4 ; 2.2 Load verification calculation: The rated safe lifting capacity of the bridge crane is 32t × 1.25 = 40t, which is greater than the self-weight of the steam drum of 38t, thus meeting the safety factor requirements of the hoisting specifications.

[0025] Step 3: The first section of the pulley system is used to lift and transfer the load across the column. 3.1 Start the 75hp winch on the +38m platform to pull the first section of four pulley blocks of steel columns 201-202 in column DE. Connect the lower hook of the pulley block to the bracket lifting lug. Simultaneously and slowly wind up the rope to lift the steam drum bracket assembly laterally from the temporary platform of steel column 201 to the area of ​​steel column 202 in column 1 / D2-E, completing the cross-column relay transfer. See the process diagram. Figure 5 .

[0026] Step 4: Raise the second pulley block to the high-position installation platform: 4.1 Switch the winch traction rope to the second pulley block of steel columns 202-203 in column 1 / D2-E. The winch will then uniformly and synchronously wind up the rope to lift the equipment, raising the entire steam drum support frame to the +54m steam drum design installation elevation platform height. It will then be laterally moved to the temporary fixed position on steel column 202. See the process diagram below. Figure 6 .

[0027] Step 5: Remove the equipment from the bracket and install it precisely in place: 5.1 Temporary Fixing of the Bracket: The bottom of the bracket is temporarily fixed by spot welding to the pre-embedded steel plate of the +54m platform. The flexible binding strap between the steam drum and the bracket is removed. The connection point between the bracket lifting lug and the rigging is cut by gas cutting to isolate the steam drum body from the lifting bracket. The gas cutting operation is covered with fireproof and scratch-resistant protective materials to avoid damaging the anti-corrosion layer of the steam drum and the bevel of the pipe seat. 5.2 Lateral translation and positioning of the steam drum: Activate the pulley block above the 203 steel column and slowly move the steam drum cylinder laterally to the steam drum installation support 18 designed for the 203 steel column; 5.3 Elevation and Level Fine Adjustment: Four 32t hydraulic jacks (17) are used to simultaneously lift the steam drum cylinder. The fixed end adjustment pads and the movable roller assembly of the floating end of the support are adjusted step by step. The axial and radial level of the cylinder are checked with a precision level. After meeting the equipment installation design tolerances, the hydraulic jacks (17) are withdrawn simultaneously and all the connecting bolts of the support are tightened.

[0028] Step 6: Dismantling of tooling and reinforcement systems and roof restoration: 6.1 After the equipment installation is completed and accepted, the pulley block, winch, hoisting bracket, and +49m temporary transition platform shall be dismantled in the following order from top to bottom. 6.2 Remove the cross-reinforcement diagonal bracing members of the DE column steel columns, grind the weld scars on the steel column surface, and restore the anti-corrosion coating of the steel structure; 6.3 Only a small section of roof panels at the pulley lifting points is removed, and the removal area is less than 15% of the roof demolition and modification area of ​​the traditional hoisting scheme. After the entire hoisting operation is completed, the roof panels, roof waterproofing and color plate enclosure structure are restored. 6.4 All the reinforcing components, brackets, and winch pulley systems in this set are detachable, reusable, and can be directly applied to the inversion construction of other high-level large equipment such as waste heat flues, deaerators, gravity dust collectors, overflow venturi tubes, secondary venturi tubes, and double-stage cyclone dehydrators in the factory.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for hoisting and installing large equipment on a high-level platform in a converter steelmaking workshop, characterized in that, Using a bridge crane and a temporary transition support platform, eight sets of pulley blocks are employed to transfer large equipment from the ground to the elevated platform. The construction steps include the following: Step 1: Pre-hoisting reinforcement and prefabrication installation of tools; installation of cross-bracing reinforcement members within the range of steel columns 201-203 of column 1 / D2-E in the factory building; welding of thickened reinforcing plates to the roof pulley suspension points; erection of a temporary transition bearing platform at +49m elevation and completion of rated load test; prefabrication of brackets; assembly of winches and eight sets of pulley blocks on site and completion of tensile load test; stable placement of the large equipment to be installed on the bracket panel, and use flexible strapping to limit and fix the equipment. Step 2: The bridge crane vertically lifts the equipment to the intermediate transition position. The bridge crane hooks the four corner lugs of the bracket and lifts the large equipment and bracket assembly vertically from the ±0m ground. It crosses the platforms of each floor of the factory building to the temporary transition platform at the +49m elevation. The hook is slowly lowered to place the assembly smoothly on the temporary platform, completing the first transfer. Step 3: The first section of the pulley block is used for cross-column relay lateral transfer. Start the +38m platform winch to pull the first group of four pulley blocks of steel columns 201-202 in column DE. The lower hook of the pulley block is connected to the bracket lifting lug. Simultaneously and slowly wind up the rope to lift the bracket assembly from the temporary platform of steel column 201 to the axis area of ​​column 1 / D2-E 202, thus completing the cross-column relay transfer. Step 4: The second pulley block is raised to the high-level installation platform. The winch is switched to pull the wire rope to the second group of four pulley blocks of steel columns 202-203 in column 1 / D2-E. The winch synchronously and uniformly winds up the rope to raise the large equipment. The entire bracket is raised to the design installation elevation platform height of +54m. It is then moved laterally to the temporary fixed position of column 202. Step 5: The equipment is detached from the bracket and precisely positioned for installation. The bottom of the bracket is temporarily fixed by spot welding to the pre-embedded plate of the +54m platform. The flexible binding strap between the equipment and the bracket is removed. The connection point between the bracket lifting lug and the rigging is cut with gas cutting to separate the large equipment from the lifting bracket. Activate the pulley block above axis 203 and slowly move the cylinder equipment laterally to the designed installation support position of the 203 steel column; Four hydraulic jacks were used to lift the large equipment simultaneously. The fixed end adjustment pads and the movable roller assembly of the floating end of the support were adjusted. After the cylinder level was checked with a level and met the design tolerance, the hydraulic jacks were removed and all the connecting bolts of the support were tightened. Step 6: Dismantle the tooling and reinforcement system and restore the roof. After the large equipment installation is accepted, dismantle the pulley block, winch, hoisting bracket, and +49m temporary transition platform in sequence; dismantle the steel column reinforcement diagonal tie rods of the DE column; only dismantle small sections of roof panels at the pulley lifting points. After the hoisting operation is completed, restore the roof panels, waterproofing and enclosure structure; the entire set of tooling is reused for the relocation construction of other large equipment in the workshop.

2. The hoisting and construction method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 1, characterized in that, After the steel structure reinforcement and tooling prefabrication and installation in step 1 are completed, the non-destructive testing of the reinforcement welds and the deflection deformation of the steel columns are completed; the temporary transition platform, winch, and pulley block are all tested and accepted under 1.25 times the rated load, and hoisting operations can only be carried out after all test items are qualified.

3. The hoisting and construction method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 1, characterized in that, When the equipment is detached from the bracket in step 5, protective measures should be taken throughout the gas cutting operation to avoid damaging the anti-corrosion layer of the equipment cylinder and the welding bevel.

4. The hoisting and construction method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 1, characterized in that, The entire construction process does not require the removal of large areas of the factory's roof beams, purlins, and color-coated steel sheet enclosure structure; only small sections of roof panels at the pulley suspension points need to be removed.

5. The hoisting and installation method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 1, characterized in that, The tooling includes a factory building reinforcement structure, a temporary transition support platform, brackets, and a pulley system. The factory building reinforcement structure is located in the area of ​​steel columns 201-203 in column DE of the factory building, and includes cross-bracing reinforcement rods for steel columns, column joint clamps, and roof suspension point reinforcement plates. Cross-bracing reinforcement members are installed between the steel columns in column D, 1 / D2, and E, with both ends of the rods locked to the flanges of the steel columns by clamp bolts. Thickened reinforcement plates are welded at the +61m roof pulley suspension point. The temporary transition support platform is built at the +49m elevation platform of the factory building, at the equipment hoisting holes of steel columns 201-202 in column CD, supported by multiple I-beam columns for the lower main beam. The platform panel is made of anti-slip thickened steel plate, and high protective railings are installed around it. The bracket is a flat-plate load-bearing structure. Lifting lugs with through holes are welded to the four corners of the bracket panel. Multiple vertical support ribs are installed at the bottom of the bracket. The cylindrical equipment to be lifted is placed on the bracket panel and secured with flexible strapping. The pulley system includes a workshop bridge crane, a winch, and two sets of pulleys with a total rated load of eight. The safety factor for the rated load of the bridge crane is 1.

25. The winch is fixedly installed on a +38m low-level platform in the factory building. The first set of four pulleys is arranged between steel columns 201-202 in column DE, and the second set of four pulleys is arranged at the roof lifting point above steel columns 202-203 in column 1 / D2-E at an elevation of +54m. The lower hooks of the pulleys are connected to the lifting lugs at the four corners of the bracket via wire rope slings.

6. The hoisting and construction method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 1, characterized in that, The rated safe lifting weight of the bridge crane is suitable for the overall lifting operation of large cylindrical equipment such as steam drums.

7. The hoisting and installation method for large equipment on a high-level platform in a converter steelmaking workshop according to claim 6, characterized in that, The large cylindrical equipment of the steam drum type is any one of the following: steam drum, waste heat flue, deaerator, gravity dust collector, overflow venturi tube, secondary venturi tube, or double-stage cyclone dehydrator.

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