Construction method for hoisting steel ladle turret revolving body of steelmaking continuous casting machine

Abstract

The invention discloses a construction method for hoisting a steel-making continuous casting machine steel ladle turret revolving body, and belongs to the technical field of steel-making continuous casting machine steel ladle turret installation. The construction method comprises the following construction steps: loading materials and assembling the revolving body in an off-line manner; a hoisting point and a supporting protection device are arranged; a loading span 300 / 75t bridge crane is hoisted to a loading position through a 300t main hook; and air relay inter-span double-crane lifting is carried out in place. The method has the advantages that the construction period is shortened due to off-line assembly, and installation of other equipment is not affected; in the hoisting preparation stage, protection facilities such as a supporting rod, a pull rod, a pile pier and inclined iron are arranged, and the revolved body is protected against plastic deformation caused by large dead weight in the hoisting process; according to the overhead relay inter-span double-crane lifting, the construction time of a bridge crane occupying a casting span host area is reduced to the maximum extent, the overhead operation is reduced, the safety risk is reduced, and the construction cost is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of installation of ladle turrets for steel-making continuous casting machines, and particularly relates to a construction method for hoisting the rotating body of the ladle turret of a steel-making continuous casting machine, namely, a construction method for hoisting the rotating body of the ladle turret of a steel-making continuous casting machine using an aerial relay span lifting method. The present invention is suitable for installation and construction projects of the rotating body of the ladle turret of a steel-making continuous casting machine, which are difficult to assemble, the hoisting position is beyond the operating range of a bridge crane, the installation position cannot occupy a bridge crane for a long time, and the hoisting difficulty is high. Background Art

[0002] The ladle turret of a continuous casting machine is primarily used to transfer heavy ladles from the loading span to the casting span. After casting is complete, empty ladles are returned to the loading span. Due to its specialized function, the ladle turret can only be located on the third-level platform directly below the shared track beams used by the loading and casting span bridge cranes. Consequently, the assembly and hoisting of the ladle turret components are outside the operating range of the loading and casting span bridge cranes.

[0003] The ladle turret rotating body consists of 1 turntable, 2 brackets, 4 connecting rods, 2 left saddles, 2 right saddles, 2 lifting arms, 2 lifting cylinders, 2 sets of weighing devices, 14 spherical bearing assemblies, 1 set of ladder platform railings, etc. The total weight after assembly is 154.47t.

[0004] The traditional construction method involves using two bridge cranes, one for the loading span and one for the casting span, to lift and install the rotating body using a custom-made shoulder beam. The first step is to fabricate a 12,000mm-long shoulder beam. The second step is to use a bridge crane, one for each span, to lift and assemble the components using the shoulder beam. This method has two drawbacks: First, the construction period is 12 days, and one bridge crane, one for each span, must be occupied for a long period of time. This seriously impacts the equipment installation progress in both spans, particularly preventing the installation of equipment in the main casting span area, leading to work delays and delays. Second, due to the heavy weight of the various components of the ladle turret and the small distance between the top of the equipment and the bottom of the bridge crane's track beam, the lifting operation is difficult, involves numerous overhead operations, carries significant safety risks, requires a high level of manpower, and results in high construction costs.

[0005] To minimize construction time and costs while ensuring safety and quality, the decision was made to utilize an aerial relay span-to-span lifting method to install the ladle turret of the continuous casting machine. The following steps were taken: First, the turret was assembled offline in the loading bay; second, the lifting points and support guards were set; third, a 300t main hook of a 300 / 75t bridge crane was hoisted to the loading position; and fourth, dual cranes were used to lift the turret into position using aerial relay spans. This method, which required four days for assembly and two hours for hoisting, reduced the installation time of the equipment in both spans to just two hours. This method enabled more efficient and rapid completion of the construction task, resolving various challenges associated with traditional construction methods. Summary of the Invention

[0006] The purpose of the present invention is to provide a construction method for hoisting the gyroscopic body of the ladle turret of a steelmaking continuous casting machine using an aerial relay span-to-span lifting method. This method solves the problem that the installation of the gyroscopic body of the ladle turret of a steelmaking continuous casting machine requires the use of a bridge crane with two spans, namely a loading span and a casting span, which results in long construction time, high construction costs, and a significant impact on the installation of other equipment. The present invention provides time and process guarantees for the smooth progress of construction, greatly reducing construction costs, shortening construction time, and minimizing the impact on the installation of other equipment. The specific process steps and control technical parameters are as follows:

[0007] 1) Feasibility simulation calculation of bridge crane aerial relay span double crane lifting

[0008] Parameters of the 300 / 75t loading span bridge crane 1: The 300t main hook 2 has a limit height of 24,000mm and a maximum distance from the center of the ladle turret of 4,400mm; the 75t auxiliary hook 3 has a limit height of 27,700mm and a maximum distance from the center of the ladle turret of 3000mm.

[0009] The 140t bridge crane with a casting span has a limit height of 26,000mm and a maximum distance from the center of the ladle turret of 3,438mm.

[0010] After the 300t main hook 2 of the loading span 300 / 75t bridge crane 1 lifts the ladle turret slewing body 5 to the right side of the installation position and sends it to the extreme position, the extreme distance between the center of the lifting eye 7 on the end face of the left saddle 6 of the ladle turret slewing body 5 and the casting span 140t bridge crane 4 is 3438-(14170÷2-4400)=753mm. During lifting, the inclination angle of the casting span 140t bridge crane 4 is arctg(753÷8116)=5°, which can meet the lifting needs of two machines.

[0011] 2) Calculation of load capacity of bridge crane

[0012] When lifting with two machines between spans, only the 140t bridge crane 4 of the casting span and the 75t auxiliary hook 3 of the 300 / 75t bridge crane of the loading span can be used for lifting. The lifting load is evenly distributed, so the maximum load of a single bridge crane is 75t.

[0013] Take the dynamic load factor k1 = 1.1;

[0014] The maximum allowable lifting weight w = 75*2 / k1 = 136.4t

[0015] Calculation of the total weight of the ladle turret after assembly:

[0016] Serial number name unit quantity Weight kg Total weight kg Remark 1 Turntable indivual 1 29749.5 29749.5 2 bracket indivual 2 7703 15406 3 link indivual 4 1382 5528 4 Right saddle indivual 2 6988.1 13976.2 5 Weighing device indivual 2 822.1 1644.2 6 lifting arm indivual 2 18557 37114 7 Left saddle indivual 2 6988.1 13976.2 8 Steel hanging device indivual 4 70.46 281.84 9 Spherical bearing assembly indivual 1 7417.2 7417.2 10 Lift cylinder assembly indivual 2 12840.2 25680.4 11 Platform ladder railings indivual 1 3695 3695 154468.54

[0017] That is, the weight of the ladle turret's rotating body after assembly is 154.47t>136.4t, which exceeds the maximum allowable lifting weight. Therefore, the lifting cylinder assembly totaling 25.68t is not assembled for the time being. At this time, the lifting weight is 128.788t<136.4t, which meets the lifting requirements.

[0018] 3) Calculation of the length of wire rope buckle for lifting

[0019] ①、Calculation of the length of 300t main hook 2 main hoist wire rope buckle 8

[0020] The height of the 300t main hook 2 when it is lifted to the upper limit is 24000mm. When the ladle turret rotary body 5 is just lifted to the third-layer platform, the bottom height of the lifting arm 9 is 19950-2161=17789mm. At this time, the straight-line distance between the 300t main hook 2 and the bottom of the lifting arm 9 is 6211mm. The bottom width of the lifting arm is 500mm. Four 9800mm long steel wire ropes are used for lifting with an 8-fold buckle. During lifting, the maximum height of the ladle turret rotary body 5 rising to the third-layer platform is 6211-(9800-500)÷2=1561mm, which meets the construction needs.

[0021] ② Calculation of the length of the 140t bridge crane's 4 lifting wire rope buckle 2 (10) and the 75t auxiliary hook's 3 lifting wire rope buckle 3 (11)

[0022] The upper limit height of 140t bridge crane 4 is 26000mm, which is less than the upper limit height of 75t auxiliary hook 3, which is 27700mm. The calculation is based on the wire rope buckle 210 used for hoisting of 140t bridge crane 4.

[0023] The height of the 140t bridge crane 4 when it is lifted to the upper limit is 26000mm. After the ladle turret rotary body 5 is installed in place, the height of the lifting eye 7 on the left saddle 6 is 17750mm. At this time, the straight-line distance between the 140t bridge crane 4 and the lifting eye 7 is 8250mm. Two 12000mm long steel wire ropes are used and folded in half for lifting. During lifting, the ladle turret rotary body 5 can exceed the installation position by more than 2000mm, meeting the construction needs.

[0024] Similarly, the length of the wire rope buckle 11 used for lifting the 75t auxiliary hook 3 is also selected to be 12000mm long.

[0025] 4) Angle calculation of the lifting lug 1 (7) on the left saddle (6) and the lifting lug 2 (13) on the right saddle (12)

[0026] In order to make the force on the lifting lug 1 7 and the lifting lug 2 13 more reasonable during lifting, the horizontal angle between the lifting lug 1 7 and the end face of the left saddle 6 and the horizontal angle between the lifting lug 2 13 and the end face of the right saddle 12 cannot be selected arbitrarily. The installation dimensions of the left saddle 6 and the right saddle 12 are exactly the same, and the wire rope buckles used for lifting are also the same length. Therefore, the angles of the lifting lug 1 7 and the lifting lug 2 13 are also exactly the same. The angle calculation is based on the lifting lug 2 13 on the right saddle 12.

[0027] The center distance between the two right saddle end faces is 4725 mm, and the service length of the wire rope buckle 11 is 6000 mm. Then, the horizontal angle between the lifting lug 13 on the right saddle 12 and the end face of the right saddle 12 is arccos(4725÷2÷6000)=68°.

[0028] 5) Calculation of wire rope diameter

[0029] ①、Calculation of the diameter of the steel wire rope buckle 8 for the integral lifting of the ladle turret with a 300t main hook

[0030] The weight of the assembled ladle turret 5 is 128.8t. The support rod 14, the pull rod 15, and the wire rope buckle 1, 10, and 11 weigh a total of 3t. The calculated load is 131.8t. The 6*37+1 type wire rope with a diameter of φ65 is selected. Its main parameters are:

[0031] Breaking force of single wire rope buckle = 147.875t

[0032] For hoisting, four φ65mm steel wire ropes with a 8-point four-point system are used, folded in half (equivalent to two steel wire ropes at each lifting point). The maximum load-bearing capacity of a single lifting point steel wire rope is: 147.875t*2=295.75t

[0033] Safety factor of wire rope buckle 8: 295.75÷(131.8÷8)=17.95, which meets the lifting requirements.

[0034] ② Calculation of the diameter of the wire rope buckle 10 for lifting of 140t bridge crane and the wire rope buckle 11 for lifting of 75t auxiliary hook:

[0035] The double-machine lifting wire rope buckle 210 and wire rope buckle 311 both use 6*37+1 type wire rope with a diameter of φ48, 12m long and folded in half for use, 4 ropes for four-point lifting, and the breaking force of a single lifting wire rope buckle 210 and wire rope buckle 311 is 134t.

[0036] Safety factor of wire rope buckle 2 10 and wire rope buckle 3 11: 134÷(131.8÷8)=8.13, which meets the lifting requirements.

[0037] 6) Offline assembly of ladle turret 5

[0038] To avoid interfering with the installation of the casting and loading bay equipment, the ladle turret's rotating body 5 is assembled on the easternmost side of the loading bay building. This area serves as a spare parts storage area and can be occupied long-term. The assembly process follows: turntable 16 is leveled → bracket 17 is positioned and aligned according to design dimensions → connecting rod 18 is assembled → lifting arm 9 is assembled and supported → left saddle 6 is assembled → right saddle 12 is assembled → turntable 16 and bracket 17 are assembled → ladder platform railing 19 is assembled. The weighing device 20 and steel hanging device 21 are assembled along with the left and right saddles 6 and 12. The spherical bearing assembly 22 is assembled along with all other components.

[0039] 7) Preparation for hoisting of ladle turret 5

[0040] A lifting lug 7 is welded to each end face of the two left saddles 6, and a lifting lug 2 13 is welded to each end face of the two right saddles 12. The horizontal angle between the lifting lug 7 and the end face of the left saddle 6 is 68°, and the horizontal angle between the lifting lug 7 and the end face of the right saddle 13 is 68°. The lifting lug 7 and the lifting lug 2 13 are made of 400mm*300mm*50mm steel plates, and the center hole diameter is 2. A reinforcing rib is made of t=30mm steel plate on each side; a support rod 14 is made of H300*300 steel between the two left saddles 6 and the two right saddles 12; four pull rods 15 are made of t=30mm steel plate between the lifting arm 9 and the bracket 17; the gap between the connecting rod 18 and the bracket 17 is filled with a pile pier 23 and an inclined iron 24 made of H200*200 steel; a steel bar is used at the corner of the lifting arm 9 where the wire rope buckle 8 is passed. A semicircular thick-walled tube is used as a protective angle 25, and a rope retaining plate 26 is welded with a 600mm*100mm*30mm steel strip at the junction of the lifting arm 9 and the bracket 17.

[0041] 8) Aerial relay lifting and hoisting of the ladle turret 5

[0042] Use the 300t main hook 2 of the loading span 300 / 75t bridge crane 1 to lift the ladle turret slewing body 5, and at the same time hang the wire rope buckle 3 11 of the 75t auxiliary hook 3 and connect it with the lifting lug 2 13 on the right saddle 12, and lift the ladle turret slewing body 5 to the extreme position on the right side of the installation position; connect the wire rope buckle 2 10 used for lifting the casting span 140t bridge crane 4 to the lifting lug 1 7 of the left saddle 6, and at the same time lift the 75t auxiliary hook 3 and the 140t bridge crane 4 and tighten the wire rope buckle 3 11 and wire rope buckle 2 10, and synchronously lift the 75t auxiliary hook 3 and the 140t bridge crane 4 until the wire rope buckle 1 8 is completely relaxed. This process requires the 75t auxiliary hook 3 to be lifted along with the ladle turret. The turret slewing body 5 is moved horizontally by 753mm in the direction of the casting span, and the 300t main hook 2 is slowly lowered until the wire rope buckle 8 is completely removed; the 75t auxiliary hook 3 and the 140t bridge crane 4 are used to lift the ladle turret slewing body 5 horizontally in the direction of the casting span until it is aligned with the installation position; the 75t auxiliary hook 3 and the 140t bridge crane 4 are synchronously lifted again until the lower surface of the ladle turret slewing body 5 exceeds the height of the installation position by 100mm; finally, the 300 / 75t bridge crane 1 with the loading span and the 140t bridge crane 4 with the casting span are used to lift the ladle turret slewing body 5 horizontally to the installation position and align it, install the connecting bolts, and synchronously lower it into place to complete the lifting.

[0043] The outstanding innovations of the present invention include at least the following:

[0044] Feasibility simulation calculation of the bridge crane aerial relay span lifting with two cranes described in step 1);

[0045] In order to make the force of the lifting lug 1 7 and the lifting lug 2 13 more reasonable during lifting, the horizontal angle between the lifting lug 1 7 and the end face of the left saddle 6 and the horizontal angle between the lifting lug 2 13 and the end face of the right saddle 12 cannot be selected arbitrarily. The center distance between the two right saddle end faces is 4725 mm, and the usable length of the wire rope buckle 3 11 is 6000 mm. Then, the horizontal angle between the lifting lug 2 13 on the right saddle 12 and the end face of the right saddle 12 is arccos(4725÷2÷6000)=68°.

[0046] As described in step 7), a support rod 14 is made between the two left saddles 6 and the two right saddles 12 with H300*300 steel; four pull rods 15 are made of t=30mm steel plate between the lifting arm 9 and the bracket 17; the gap between the connecting rod 18 and the bracket 17 is filled with a pile pier 23 and an inclined iron 24 made of H200*200 steel; and a wire rope buckle 8 is used at the corner of the lifting arm 9. A semicircular thick-walled tube is used as an angle protector 25, and a rope retaining plate 26 is welded with a 600mm*100mm*30mm steel strip at the junction of the lifting arm 9 and the bracket 17.

[0047] The 300t main hook 2 of the loading span 300 / 75t bridge crane 1 described in step 8) is used to lift the ladle turret slewing body 5, and at the same time, the wire rope buckle 3 11 of the 75t auxiliary hook 3 is hung and connected to the lifting lug 2 13 on the right saddle 12, and the ladle turret slewing body 5 is lifted to the extreme position on the right side of the installation position; the wire rope buckle 2 10 used for lifting the casting span 140t bridge crane 4 is connected to the lifting lug 1 7 of the left saddle 6, and the 75t auxiliary hook 3 and the 140t bridge crane 4 are lifted at the same time and the wire rope buckle 2 10 and the wire rope buckle 3 12 are tightened, and the 75t auxiliary hook 3 and the 140t bridge crane 4 are lifted synchronously until the wire rope buckle 1 8 is completely relaxed. This process requires the 75t auxiliary hook 3 Move the ladle turret swivel body 5 horizontally 753mm in the direction of the casting span, and slowly lower the 300t main hook 2 until the wire rope buckle 8 is completely removed; use the 75t auxiliary hook 3 and the 140t bridge crane 4 to lift the ladle turret swivel body 5 horizontally in the direction of the casting span until it is aligned with the installation position; synchronously lift the 75t auxiliary hook 3 and the 140t bridge crane 4 again until the lower surface of the ladle turret swivel body 5 exceeds the height of the installation position by 100mm; finally, use the 300 / 75t bridge crane 1 with a loading span and the 140t bridge crane 4 with a casting span to lift the ladle turret swivel body 5 horizontally to the installation position and align it, install the connecting bolts, and synchronously lower it into place to complete the lifting.

[0048] The advantages of the present invention are: offline assembly, shortening the construction period, and not affecting the installation of other equipment, solving the problem that the equipment and structures in the casting span main machine area cannot be hoisted during the online assembly and installation of the ladle turntable because other bridge cranes have no station position; the lifting lug is set at a horizontal angle of 68° to the saddle end face when welding, and the force on the lifting lug is more reasonable during hoisting; support rods, pull rods, pile piers, inclined irons and other protective facilities are set in the hoisting preparation stage to protect the rotating body from plastic deformation due to its own weight during the hoisting process; the aerial relay span double-machine lifting minimizes the construction time occupied by the bridge crane in the casting span main machine area, reduces high-altitude operations, reduces safety risks, and saves construction costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is the layout diagram of the ladle turret, including: 350 / 75t bridge crane 1, 300t main hook 2, 75t auxiliary hook 3, 140t bridge crane 4, ladle turret rotating body 5, left saddle 6, and lifting eye 7.

[0050] Figure 2This is the assembly diagram of the ladle turret. It includes the 300t main hook 2, the 75t auxiliary hook 3, the left saddle 6, the first lifting eye 7, the first wire rope buckle 8, the lifting arm 9, the third wire rope buckle 11, the right saddle 12, the second lifting eye 13, the pull rod 15, the turret 16, the support 17, the connecting rod 18, the weighing device 20, the steel hanging device 21, the pile pier 23, the inclined iron 24, the protective angle 25, and the rope retaining plate 26.

[0051] Figure 3 This is a cross-sectional view of the ladle turret rotary assembly, which includes the turntable 16, the ladder platform railing 19, and the spherical bearing assembly 22.

[0052] Figure 4 Make a drawing for the tie rod. Among them, tie rod 15.

[0053] Figure 5 Make a drawing for the pile pier. Among them, pile pier 25.

[0054] Figure 6 Figure 140t bridge crane, part 4, wire rope buckle 3 11, right saddle 12, and lifting eye 2 13.

[0055] Figure 7 The figure shows the support rod arrangement, wherein the ladle turret includes a rotating body 5, a left saddle 6, a right saddle 12, and support rods 14.

[0056] Figure 8 Diagram of the aerial relay lift between spans of the ladle turret. The diagram shows the 350 / 75t bridge crane (1), the 300t main hook (2), the 75t auxiliary hook (3), the 140t bridge crane (4), the ladle turret (5), the wire rope buckle (1) (8), the wire rope buckle (2) (10), and the wire rope buckle (3) (11).

[0057] Figure 9 This diagram shows the lifting process between spans of the ladle turret's rotating body. It includes the 350 / 75t bridge crane (1), the 300t main hook (2), the 75t auxiliary hook (3), the 140t bridge crane (4), the ladle turret's rotating body (5), the wire rope buckle 2 (10), and the wire rope buckle 3 (11). DETAILED DESCRIPTION

[0058] Example 1

[0059] Guangdong Southern East China Sea 230x1350mm 2 The ladle turrets for the installation project of two twin-machine, twin-strand slab continuous casting machines were arranged on the +13.59m platform directly below the common track beam of the loading span and casting span bridge cranes. As a result, the assembly and hoisting operations of the various components of the ladle turrets were not within the operating range of the loading span and casting span bridge cranes.

[0060] The ladle turret rotating body consists of 1 turntable, 2 supports, 4 connecting rods, 2 left saddles, 2 right saddles, 2 lifting arms, 2 lifting cylinders, 2 sets of weighing devices, 1 set of ladder platform railings, etc. The total weight after assembly is 154.47t.

[0061] To minimize construction time and costs while ensuring safety and quality, the decision was made to utilize an aerial relay span-to-span lifting method to install the ladle turret of the continuous casting machine. The following steps were taken: First, the turret was assembled offline in the loading bay; second, the lifting points and support guards were set; third, a 300t main hook of a 300 / 75t bridge crane was hoisted to the loading position; and fourth, dual cranes were used to lift the turret into position using aerial relay spans. This method required four days for assembly and two hours for hoisting, reducing the equipment installation time for both spans to just two hours, completing the construction task more efficiently and quickly.

[0062] The specific process steps and control technical parameters are as follows:

[0063] 1) Feasibility simulation calculation of bridge crane aerial relay span double crane lifting

[0064] Parameters of 300 / 75t loading span bridge crane 1: 300t main hook 2 limit height 24000m, the maximum distance from the center of the ladle turret is 4400mm, 75t auxiliary hook 3 limit height 27700mm, the maximum distance from the center of the ladle turret is 3000mm.

[0065] The 140t bridge crane with a casting span has a limit height of 26,000mm and a maximum distance from the center of the ladle turret of 3,438mm.

[0066] After the 300t main hook 2 of the loading span 300 / 75t bridge crane 1 lifts the ladle turret slewing body 5 to the right side of the installation position and sends it to the extreme position, the extreme distance between the center of the lifting eye 7 on the end face of the left saddle 6 of the ladle turret slewing body 5 and the casting span 140t bridge crane 4 is 3438-(14170÷2-4400)=753mm. During lifting, the inclination angle of the casting span 140t bridge crane 4 is arctg(753÷8116)=5°, which can meet the lifting needs of two machines.

[0067] 2) Calculation of load capacity of bridge crane

[0068] When lifting with two machines between spans, only the 140t bridge crane 4 of the casting span and the 75t auxiliary hook 3 of the 300 / 75t bridge crane of the loading span can be used for lifting. The lifting load is evenly distributed, so the maximum load of a single bridge crane is 75t.

[0069] Take the dynamic load factor k1 = 1.1;

[0070] The maximum allowable lifting weight w = 75*2 / k1 = 136.4t

[0071] Calculation of the total weight of the ladle turret after assembly:

[0072] Serial number name unit quantity Weight kg Total weight kg Remark 1 Turntable indivual 1 29749.5 29749.5 2 bracket indivual 2 7703 15406 3 link indivual 4 1382 5528 4 Right saddle indivual 2 6988.1 13976.2 5 Weighing device indivual 2 822.1 1644.2 6 lifting arm indivual 2 18557 37114 7 Left saddle indivual 2 6988.1 13976.2 8 Steel hanging device indivual 4 70.46 281.84 9 Spherical bearing assembly indivual 1 7417.2 7417.2 10 Lift cylinder assembly indivual 2 12840.2 25680.4 11 Platform ladder railings indivual 1 3695 3695 154468.54

[0073] That is, the weight of the ladle turret's rotating body after assembly is 154.47t>136.4t, which exceeds the maximum allowable lifting weight. Therefore, the lifting cylinder assembly totaling 25.68t is not assembled for the time being. At this time, the lifting weight is 128.788t<136.4t, which meets the lifting requirements.

[0074] 3) Calculation of the length of wire rope buckle for lifting

[0075] ①、Calculation of the length of 300t main hook 2 main hoist wire rope buckle 8

[0076] The height of the 300t main hook 2 when it is lifted to the upper limit is 24000mm. When the ladle turret rotary body 5 is just lifted to the 13590mm platform, the bottom height of the lifting arm 9 is 19950-2161=17789mm. At this time, the straight-line distance between the 300t main hook 2 and the bottom of the lifting arm 9 is 6211mm. The bottom width of the lifting arm is 500mm. Four 9800mm long steel wire ropes are used for lifting with an 8-fold buckle. During lifting, the maximum height of the ladle turret rotary body 5 rising to the 13590mm platform is 6211-(9800-500)÷2=1561mm, which meets the construction needs.

[0077] ② Calculation of the length of the 140t bridge crane's 4 lifting wire rope buckle 2 (10) and the 75t auxiliary hook's 3 lifting wire rope buckle 3 (11)

[0078] The upper limit height of 140t bridge crane 4 is 26000mm, which is less than the upper limit height of 75t auxiliary hook 3, which is 27700mm. The calculation is based on the wire rope buckle 210 used for hoisting of 140t bridge crane 4.

[0079] The height of the 140t bridge crane 4 when it is lifted to the upper limit is 26000mm. After the ladle turret rotary body 5 is installed in place, the height of the lifting eye 7 on the left saddle 6 is 17750mm. At this time, the straight-line distance between the 140t bridge crane 4 and the lifting eye 7 is 8250mm. Two 12000mm long steel wire ropes are used and folded in half for lifting. During lifting, the ladle turret rotary body 5 can exceed the installation position by more than 2000mm, meeting the construction needs.

[0080] Similarly, the length of the wire rope buckle 11 used for lifting the 75t auxiliary hook 3 is also selected to be 12000mm long.

[0081] 4) Angle calculation of the lifting lug 1 (7) on the left saddle (6) and the lifting lug 2 (13) on the right saddle (12)

[0082] In order to make the force on the lifting lug 1 7 and the lifting lug 2 13 more reasonable during lifting, the horizontal angle between the lifting lug 1 7 and the end face of the left saddle 6 and the horizontal angle between the lifting lug 2 13 and the end face of the right saddle 12 cannot be selected arbitrarily. The installation dimensions of the left saddle 6 and the right saddle 12 are exactly the same, and the wire rope buckles used for lifting are also the same length. Therefore, the angles of the lifting lug 1 7 and the lifting lug 2 13 are also exactly the same. The angle calculation is based on the lifting lug 2 13 on the right saddle 12.

[0083] The center distance between the two right saddle end faces is 4725 mm, and the service length of the wire rope buckle 11 is 6000 mm. Then, the horizontal angle between the lifting lug 13 on the right saddle 12 and the end face of the right saddle 12 is arccos(4725÷2÷6000)=68°.

[0084] 5) Calculation of wire rope diameter

[0085] ①、Calculation of the diameter of the steel wire rope buckle 8 for the integral lifting of the ladle turret with a 300t main hook

[0086] The weight of the assembled ladle turret 5 is 128.8t. The support rod 14, the pull rod 15, and the wire rope buckle 1, 10, and 11 weigh a total of 3t. The calculated load is 131.8t. The 6*37+1 type wire rope with a diameter of φ65 is selected. Its main parameters are:

[0087] Breaking force of single wire rope buckle = 147.875t

[0088] For hoisting, four φ65mm steel wire ropes with a 8-point four-point system are used, folded in half (equivalent to two steel wire ropes at each lifting point). The maximum load-bearing capacity of a single lifting point steel wire rope is: 147.875t*2=295.75t

[0089] Safety factor of wire rope buckle 8: 295.75÷(131.8÷8)=17.95, which meets the lifting requirements.

[0090] ② Calculation of the diameter of the wire rope buckle 10 for lifting of 140t bridge crane and the wire rope buckle 11 for lifting of 75t auxiliary hook:

[0091] The double-machine lifting wire rope buckle 210 and wire rope buckle 311 both use 6*37+1 type wire rope with a diameter of φ48, 12m long and folded in half for use, 4 ropes for four-point lifting, and the breaking force of a single lifting wire rope buckle 210 and wire rope buckle 311 is 134t.

[0092] Safety factor of wire rope buckle 2 10 and wire rope buckle 3 11: 134÷(131.8÷8)=8.13, which meets the lifting requirements.

[0093] 6) Offline assembly of ladle turret 5

[0094] To avoid interfering with the installation of the casting and loading bay equipment, the ladle turret's rotating body 5 is assembled on the easternmost side of the loading bay building. This area serves as a spare parts storage area and can be occupied long-term. The assembly process follows: turntable 16 is leveled → bracket 17 is positioned and aligned according to design dimensions → connecting rod 18 is assembled → lifting arm 9 is assembled and supported → left saddle 6 is assembled → right saddle 12 is assembled → turntable 16 and bracket 17 are assembled → ladder platform railing 19 is assembled. The weighing device 20 and steel hanging device 21 are assembled along with the left and right saddles 6 and 12. The spherical bearing assembly 22 is assembled along with all other components.

[0095] 7) Preparation for hoisting of ladle turret 5

[0096] A lifting lug 7 is welded to the end faces of the two left saddles 6, and a lifting lug 2 13 is welded to the end faces of the two right saddles 12. The horizontal angle between the lifting lug 7 and the end face of the left saddle 6 is 68°, and the horizontal angle between the lifting lug 13 and the end face of the right saddle 12 is 68°. The lifting lug 7 and the lifting lug 2 13 are made of 400mm*300mm*50mm steel plates, and the center hole diameter is 1. A reinforcing rib is made of t=30mm steel plate on each side; a support rod 14 is made of H300*300 steel between the two left saddles 6 and the two right saddles 12; four pull rods 15 are made of t=30mm steel plate between the lifting arm 9 and the bracket 17; the gap between the connecting rod 18 and the bracket 17 is filled with a pile pier 23 and an inclined iron 24 made of H200*200 steel; a steel bar is used at the corner of the lifting arm 9 where the wire rope buckle 8 is passed. A semicircular thick-walled tube is used as a protective angle 25, and a rope retaining plate 26 is welded with a 600mm*100mm*30mm steel strip at the junction of the lifting arm 9 and the bracket 17.

[0097] 8) Aerial relay lifting and hoisting of the ladle turret 5

[0098] Use the 300t main hook 2 of the loading span 300 / 75t bridge crane 1 to lift the ladle turret slewing body 5, and at the same time hang the wire rope buckle 3 11 of the 75t auxiliary hook 3 and connect it to the lifting lug 2 13 on the right saddle 12, and lift the ladle turret slewing body 5 to the right extreme position of the installation position; connect the wire rope buckle 2 10 used for lifting the casting span 140t bridge crane 4 to the lifting lug 1 7 of the left saddle 6, and at the same time lift the 75t auxiliary hook 3 and the 140t bridge crane 4 and tighten the wire rope buckle 3 11 and the wire rope buckle 2 10, and synchronously lift the 75t auxiliary hook 3 and the 140t The bridge crane 4 is used to completely relax the wire rope buckle 8. During this process, the 75t auxiliary hook 3 is required to move 753mm horizontally along the ladle turret rotating body 5 in the direction of the casting span, and the 300t main hook 2 is slowly lowered until the wire rope buckle 8 is completely removed. The 75t auxiliary hook 3 and the 140t bridge crane 4 are used to lift the ladle turret rotating body 5 in the direction of the casting span and transport it horizontally to the installation position. The 75t auxiliary hook 3 and the 140t bridge crane 4 are then raised synchronously again until the lower surface of the ladle turret rotating body 5 exceeds the installation position by 100mm. Finally, the 300t / 75t loading span is used to lift the ladle turret rotating body 5 horizontally in the direction of the casting span.

[0099] The bridge crane 1 and the 140t casting span bridge crane 4 are used to lift the ladle turret slewing body 5 horizontally to the installation position and align it, install the connecting bolts, and simultaneously lower it into place to complete the lifting.

Claims

1. A construction method for hoisting the rotating body of the ladle turret of a steelmaking continuous casting machine, characterized in that: The specific process steps and control technical parameters are as follows: 1) Feasibility simulation calculation of bridge crane aerial relay lifting between two spans Loading span 300 / 75t bridge crane (1) parameters: 300t main hook (2) limit height 24000mm, the maximum distance from the ladle turret center is 4400mm; 75t auxiliary hook (3) limit height 27700mm, the maximum distance from the ladle turret center is 3000mm; The casting span 140t bridge crane (4) has a limit height of 26000mm and a maximum distance from the center of the ladle turret of 3438mm; After the 300t main hook (2) of the loading span 300 / 75t bridge crane (1) hoists the ladle turret rotary body (5) to the right side of the installation position and sends it to the limit position, the limit distance between the center of the lifting lug (7) on the end face of the left saddle (6) of the ladle turret rotary body (5) and the casting span 140t bridge crane (4) is 3438-(14170÷2-4400)=753mm. During the hoisting, the tilt angle of the casting span 140t bridge crane (4) is arctg(753÷8116)=5°, which can meet the lifting needs of two cranes. 2) Calculation of bridge crane load capacity When lifting with two cranes between spans, only the 140t bridge crane (4) of the casting span and the 75t auxiliary hook (3) of the 300 / 75t bridge crane of the loading span can be used for lifting. The lifting load is evenly distributed, so the maximum load of a single bridge crane is 75t. Take the dynamic load factor k1 = 1.1; The maximum allowable lifting weight w = 75*2 / k1 = 136.4t That is, the weight of the ladle turret's rotating body after assembly is 154.47t > 136.4t, exceeding the maximum allowable lifting weight. Therefore, the lifting cylinder assembly totaling 25.68t is temporarily not assembled. At this time, the lifting weight is 128.788t < 136.4t, meeting the lifting requirements. 3) Calculation of the length of the wire rope buckle for lifting, including 300t main hook (2) main hoist wire rope buckle one (8) length calculation Calculation of the length of the second wire rope buckle (10) for lifting on a 140t bridge crane (4) and the third wire rope buckle (11) for hoisting on a 75t auxiliary hook (3); 4) The horizontal angle between the first lifting lug (7) and the end face of the left saddle (6) and the horizontal angle between the second lifting lug (13) and the end face of the right saddle (12) cannot be selected arbitrarily. The installation dimensions of the left saddle (6) and the right saddle (12) are exactly the same, and the wire rope buckles used for lifting are also of the same length. Therefore, the angles of the first lifting lug (7) and the second lifting lug (13) are also exactly the same. The angle calculation is based on the second lifting lug (13) on the right saddle (12): The center distance between the two right saddle end faces is 4725 mm, and the usable length of the wire rope buckle 3 (11) is 6000 mm. Then, the horizontal angle between the second hanging ear (13) on the right saddle (12) and the end face of the right saddle (12) is arccos (4725÷2÷6000) = 68°; 5) Calculation of wire rope diameter, including Calculation of the diameter of the wire rope buckle (8) for the integral lifting of the ladle turret (5) by the 300t main hook (2). Calculation of the diameter of the second wire rope buckle (10) for lifting on a 140t bridge crane (4) and the third wire rope buckle (11) for hoisting on a 75t auxiliary hook (3); 6) Offline assembly of ladle turret (5) The ladle turret rotating body (5) is assembled at the easternmost side of the loading cross-plant building. The easternmost side of the loading cross-plant building is the spare parts storage area, which can be occupied for a long time. Assembly construction process: turntable (16) leveling → bracket (17) is positioned and aligned according to the design size → connecting rod (18) assembly → lifting arm (9) assembly and support → left saddle (6) assembly → right saddle (12) assembly → turntable (16) and bracket (17) assembly → ladder platform railing (19) assembly, weighing device (20) and steel hanging device (21) are assembled together with the left saddle (6) and right saddle (12), and joint bearing assembly (22) is assembled together with each assembly part; 7) Ladle turret rotating body (5) Hoisting preparation A lifting lug (7) is welded to the end faces of the two left saddles (6), and a lifting lug (13) is welded to the end faces of the two right saddles (12). The horizontal angle between the lifting lug (7) and the end face of the left saddle (6) is 68°, and the horizontal angle between the lifting lug 7 and the end face of the right saddle 13 is 68°. The lifting lug (7) and the lifting lug (13) are made of 400mm*300mm*50mm steel plates, and the center hole diameter is A reinforcing rib is made of t=30mm steel plate on each side; a support rod (14) is made of H300*300 steel between the two left saddles (6) and the two right saddles (12); four pull rods (15) are made of t=30mm steel plate between the lifting arm (9) and the bracket (17); the gap between the connecting rod (18) and the bracket (17) is filled with a pile pier (23) and an inclined iron (24) made of H200*200 steel; and a steel bar is used at the corner of the lifting arm (9) where the wire rope buckle (8) is passed. A semicircular thick-walled tube is used as a protective angle (25), and a rope retaining plate (26) is welded with a 600mm*100mm*30mm steel strip at the junction of the lifting arm (9) and the bracket (17); 8) Aerial relay lifting of the ladle turret (5) Use the 300t main hook (2) of the 300 / 75t bridge crane (1) with a loading span to lift the ladle turret slewing body (5), and at the same time hang the wire rope buckle 3 (11) of the 75t auxiliary hook (3) and connect it with the lifting lug 2 (13) on the right saddle (12), and lift the ladle turret slewing body (5) to the extreme position on the right side of the installation position; connect the wire rope buckle 2 (10) used for lifting of the 140t bridge crane (4) with the lifting lug 1 (7) on the left saddle (6), and at the same time lift the 75t auxiliary hook (3) and the 140t bridge crane (4) and tighten the wire rope buckle 3 (11) and the wire rope buckle 2 (10), and synchronously lift the 75t auxiliary hook (3) and the 140t bridge crane (4) until the wire rope buckle 1 (8) is completely relaxed. This process requires the 75t auxiliary hook (3) to lift the 140t bridge crane (4) and the 75t auxiliary hook (3) and the 140t bridge crane (4). (3) Move the ladle turret swivel body (5) horizontally 753mm in the direction of the casting span, and slowly lower the 300t main hook (2) until the wire rope buckle (8) is completely removed; use the 75t auxiliary hook (3) and the 140t bridge crane (4) to lift the ladle turret swivel body (5) horizontally in the direction of the casting span until it is aligned with the installation position; synchronously lift the 75t auxiliary hook (3) and the 140t bridge crane (4) again until the lower surface of the ladle turret swivel body (5) exceeds the height of the installation position by 100mm; finally, use the 300 / 75t bridge crane (1) with a loading span and the 140t bridge crane (4) with a casting span to lift the ladle turret swivel body (5) horizontally to the installation position and align it, install the connecting bolts, and synchronously lower it into place to complete the lifting.

2. The construction method for hoisting the rotating body of the ladle turret of a steelmaking continuous casting machine according to claim 1, characterized in that: Feasibility simulation calculation of the bridge crane aerial relay span double crane lifting described in step 1): after the 300t main hook (2) of the loading span 300 / 75t bridge crane (1) lifts the ladle turret slewing body (5) to the right side of the installation position and sends it to the limit position, the limit distance between the center of the lifting eye (7) of the left saddle (6) end face of the ladle turret slewing body (5) and the casting span 140t bridge crane (4) is 3438-(14170÷2-4400)=753mm. During lifting, the tilt angle of the casting span 140t bridge crane (4) is arctg(753÷8116)=5°, which can meet the double crane lifting needs.

3. The construction method for hoisting the rotating body of the ladle turret of a steelmaking continuous casting machine according to claim 1, characterized in that: In step 8), the 300t main hook (2) of the 300 / 75t bridge crane (1) with a loading span is used to lift the ladle turret slewing body (5), and at the same time, the wire rope buckle 3 (11) of the 75t auxiliary hook (3) is hung and connected to the lifting lug 2 (13) on the right saddle (12), and the ladle turret slewing body (5) is lifted to the limit position on the right side of the installation position; the wire rope buckle 2 (10) used for lifting the casting span 140t bridge crane (4) is connected to the lifting lug 1 (7) of the left saddle (6), and the 75t auxiliary hook (3) and the 140t bridge crane (4) are lifted at the same time and the wire rope buckle 2 (10) and the wire rope buckle 3 (12) are tightened, and the 75t auxiliary hook (3) and the 140t bridge crane (4) are lifted synchronously until the wire rope buckle 1 (8) is completely relaxed. This process requires The 75t auxiliary hook (3) moves horizontally 753mm along with the ladle turret rotating body (5) in the direction of the casting span, and slowly lowers the 300t main hook (2) until the wire rope buckle (8) is completely removed; the 75t auxiliary hook (3) and the 140t bridge crane (4) are used to lift the ladle turret rotating body (5) in the direction of the casting span and transport it horizontally to the installation position; the 75t auxiliary hook (3) and the 140t bridge crane (4) are synchronously lifted again until the lower surface of the ladle turret rotating body (5) exceeds the height of the installation position by 100mm; finally, the 300 / 75t bridge crane (1) with a loading span and the 140t bridge crane (4) with a casting span are used to lift the ladle turret rotating body (5) in the direction of the casting span and transport it horizontally to the installation position and align it, install the connecting bolts, and synchronously lower it into place to complete the lifting.

4. The construction method for hoisting the rotating body of the ladle turret of a steelmaking continuous casting machine according to claim 1, characterized in that: In step 3): Calculation of the length of the main hook (2) and main hoist wire rope buckle (8): When the 300t main hook (2) is lifted to the upper limit, the height is 24000mm. When the ladle turret rotary body (5) is just lifted to the third-layer platform, the bottom height of the lifting arm (9) is 19950-2161=17789mm. At this time, the straight-line distance between the 300t main hook (2) and the bottom of the lifting arm (9) is 6211mm. The bottom width of the lifting arm is 500mm. Four 9800mm long steel wire ropes (8) are used for lifting. When lifting, the maximum height of the ladle turret rotary body (5) rising to the third-layer platform is 6211-(9800-500)÷2=1561mm, which meets the construction requirements. Calculation of the length of the second wire rope buckle (10) for lifting on a 140t bridge crane (4) and the third wire rope buckle (11) for hoisting on a 75t auxiliary hook (3). The upper limit height of 26000mm of the 140t bridge crane (4) is less than the upper limit height of 27700mm of the 75t auxiliary hook (3). The calculation is based on the second wire rope buckle (10) used for hoisting of the 140t bridge crane (4): When the 140t bridge crane (4) is lifted to the upper limit, the height is 26000mm. After the ladle turret rotary body (5) is installed in place, the height of the lifting eye (7) on the left saddle (6) is 17750mm. At this time, the straight-line distance between the 140t bridge crane (4) and the lifting eye (7) is 8250mm. Two 12000mm long steel wire ropes (10) are used to fold in half for lifting. During the lifting, the ladle turret rotary body (5) can exceed the installation position by more than 2000mm, meeting the construction requirements. Similarly, the length of the wire rope buckle three (11) for hoisting the 75t auxiliary hook (3) is also selected to be 12000mm long.

5. The construction method for hoisting the rotating body of the ladle turret of a steelmaking continuous casting machine according to claim 1, characterized in that: In step 5): Calculation of the diameter of the wire rope buckle (8) for the integral lifting of the ladle turret (5) using the 300t main hook (2): The weight of the ladle turret rotary body (5) after assembly is 128.8t. The support rod (14), the pull rod (15) and the wire rope buckle 1 (8), the wire rope buckle 2 (10) and the wire rope buckle 3 (11) weigh a total of 3t. The calculated load is 131.8t. The wire rope of type 6*37+1 with a diameter of φ65 is selected. Its main parameters are: Breaking force of single wire rope buckle (8) = 147.875t, For hoisting, four φ65mm steel wire ropes with one (8) buckle are used for four-point hoisting, and they are folded in half (equivalent to two steel wire ropes with one (8) buckle at each hoisting point). The maximum load-bearing capacity of a single hoisting point steel wire rope with one (8) buckle is: 147.875t*2=295.75t, Safety factor of wire rope buckle (8): 295.75÷(131.8÷8)=17.95, meeting the lifting requirements; Calculation of the diameter of the second wire rope buckle (10) for lifting on a 140t bridge crane (4) and the third wire rope buckle (11) for hoisting on a 75t auxiliary hook (3): The double-machine lifting wire rope buckle 2 (10) and wire rope buckle 3 (11) are both made of 6*37+1 type wire rope with a diameter of φ48, 12m long and folded in half for use, and four wire ropes are used for four-point lifting. The breaking force of the single lifting wire rope buckle 2 (10) and wire rope buckle 3 (11) is 134t; Safety factor of wire rope buckle 2 (10) and wire rope buckle 3 (11): 134÷(131.8÷8)=8.13, meeting the lifting requirements.

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