A tundish eccentric beam integrated lifting device without adjustment and a setting method thereof

Abstract

This application discloses an integral eccentric beam lifting device for tundishes that requires no adjustment and its installation method, relating to the field of lifting equipment technology. The device includes a lifting beam, pulley blocks, fork-shaped components, a gantry hook, and a counterweight. This integral eccentric beam lifting device for tundishes that requires no adjustment, through precise mechanical calculations and structural design in the early stages, allows the lifting device to adapt to all working conditions of the tundish from empty to full after a single assembly. This solves the cumbersome problem of frequent counterweight adjustments required by existing lifting devices, significantly shortening preparation time and greatly improving operational efficiency, especially suitable for emergency lifting scenarios. The eccentric design of the pulley blocks and the precise balance of the counterweight effectively counteract the center of gravity shift of the tundish, preventing tilting and swaying during lifting. Reliable connection and locking structures for each component strictly prevent the risk of component loosening or displacement. The overall design significantly reduces the probability of major safety accidents such as molten steel leakage.

Description

Technical Field

[0001] This application belongs to the field of lifting equipment technology, and in particular relates to an integral lifting device with an eccentric beam that does not require adjustment and a method for setting it up. Background Technology

[0002] The tundish is a crucial piece of equipment in continuous casting production, responsible for receiving molten steel and smoothly conveying it to the crystallizer. Some continuous casting machines employ a double tundish design with an eccentric center of gravity, which inherently leads to a shift in the center of gravity. As a core lifting component of the crane, the stability of the tundish lifting device directly affects production safety and operational efficiency.

[0003] Under current technology, the lifting of eccentric tundishes has significant drawbacks: conventional split-type lifting devices mostly adopt a single lifting point design, with the lifting device beam directly connected to the crane hook, lacking an eccentric balancing structure. This easily leads to tundish tilting during lifting, causing the wire rope and pulley block to tilt and rub against each other. This not only fails to meet the heavy-load lifting requirements of tundishes carrying molten steel but also poses a significant safety hazard. Furthermore, the counterweights of existing eccentric beam integral lifting devices have not undergone systematic and precise mechanical calculations. When lifting tundishes at different molten steel levels, it is necessary to repeatedly load, unload, and adjust the weight or installation position of the counterweights to maintain a vertical lifting position. This frequent adjustment operation is not only cumbersome and inefficient but also prone to causing tundish tilting due to parameter deviations, human error, or loose counterweight fixation, potentially leading to serious safety accidents such as molten steel leakage. Summary of the Invention

[0004] To address some or all of the technical problems existing in the prior art, this application provides an integral lifting device for the eccentric beam of the intermediate tundish that requires no adjustment and a method for setting it up.

[0005] This application provides an integral eccentric beam lifting device for intermediate ballasts that requires no adjustment, including a lifting beam, pulley blocks, fork-shaped components, gantry hooks, and counterweights; gantry hooks are hinged to the four corners of the lifting beam via the fork-shaped components; pulley blocks are provided on both sides of the upper part of the lifting beam, and the center line of the pulley blocks is offset from the center line of the corresponding side end of the lifting beam along its length direction; the counterweights are symmetrically fixed at both ends of the lifting beam near the pulley blocks.

[0006] Preferably, the four corners of the lifting beam are provided with mounting holes, and a fixing pin is fitted through the mounting holes. The upper end of the fork-shaped part is hinged to the lifting beam through the fixing pin.

[0007] Preferably, the lower end of the fork-shaped component is hinged to the gantry hook via a gantry hook pin, and the four sets of gantry hooks are symmetrically distributed.

[0008] Preferably, both ends of the fixed pin are provided with fixed plates, and the fixed plates are fixedly connected to the lifting beam by fixed bolts.

[0009] Preferably, a heat insulation plate is provided at the lower end of the lifting beam.

[0010] Preferably, the counterweight is fixed by fastening bolts.

[0011] A method for setting up an integral eccentric beam lifting device for intermediate tundish that requires no adjustment, comprising the following steps: Step S1: Center of gravity trajectory modeling: For the eccentric tundish, establish a model of the change in center of gravity corresponding to different liquid level heights from the empty ladle state to the state of the maximum designed molten steel capacity. Step S2: Determine the theoretical suspension point: Analyze the center of gravity data from step S1, find the range of variation of the center of gravity in the width direction [Y_min, Y_max], and take the center value of this range Y_center = (Y_min + Y_max) / 2 as the theoretical optimal suspension point center position; Step S3: Calculate the counterweight parameters: Based on the principle of torque balance, establish a static model of the spreader-intermediate bag system. With the theoretical lifting point center Y_center as a reference, calculate the mass M_p of the fixed counterweight block and its installation position L_p that need to be applied on the other side of the spreader to balance the eccentric torque generated by the intermediate bag at the Y_center position through the calculation formula. Step S4: Lifting device assembly: Determine the eccentricity of the pulley block according to the center position of the lifting point in step S2, and set the counterweight block at the designated position on the lifting device beam according to the counterweight parameters in step S3.

[0012] Preferably, in step S3, the principle of the calculation formula is: M_p×g×L_p≈M_ladle×g×|Y_ladle-Y_center|; where M_p is the mass of the counterweight, L_p is the distance between the installation position of the counterweight and the theoretical lifting point center, M_ladle is the maximum load mass of the intermediate bag, Y_ladle is the center of gravity position of the intermediate bag under maximum load, Y_center is the theoretical lifting point center position, and g is the acceleration due to gravity.

[0013] The integral lifting device and installation method for the eccentric beam of the intermediate tundish that requires no adjustment in this application have the following advantages and positive effects: (1) Through precise mechanical calculations and structural design in the early stage, the lifting device can be adapted to the full working conditions of the intermediate package from empty package to full package after one assembly. This solves the cumbersome problem of frequent adjustment of counterweight of existing lifting devices, greatly shortens the lifting preparation time, significantly improves the operation efficiency, and is especially suitable for emergency lifting scenarios.

[0014] (2) The eccentric design of the pulley block and the precise balance of the counterweight effectively counteract the center of gravity shift of the tundish, avoiding tilting and swaying during hoisting; each component adopts a reliable connection and locking structure to strictly prevent the risk of component loosening or displacement; the heat insulation plate further enhances the stability of the lifting equipment in long-term use. The overall design significantly reduces the probability of major safety accidents such as molten steel leakage. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for further understanding of the embodiments of this application and constitute a part of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a structural schematic diagram of the integral eccentric beam lifting device for intermediate tundish that requires no adjustment, as described in this application. Figure 2 This is a side view of the integral eccentric beam lifting device for intermediate tundish that requires no adjustment, as described in this application. Explanation of reference numerals in the attached figures: 1-Pulley block, 2-Lifting beam, 3-Fixing pin, 4-Fixing bolt, 5-Fixing clamp, 6-Fork-shaped part, 7-Gantry hook pin, 8-Gantry hook, 9-Fastening bolt, 10-Heat insulation board, 11-Counterweight block. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0017] like Figure 1 and Figure 2As shown, the adjustment-free intermediate eccentric beam integral lifting device of this application includes a lifting device crossbeam 2, a pulley block 1, a fork-shaped component 6, a gantry hook 8, and a counterweight block 11. The four corners of the lifting device crossbeam 2 are respectively provided with mounting holes, and fixed pins 3 are fitted through the mounting holes. Fixed clamping plates 5 are provided at both ends of the fixed pins 3, and the fixed clamping plates 5 are fixedly connected to the lifting device crossbeam 2 by fixing bolts 4, forming a bidirectional locking of the fixed pins 3, effectively preventing the fixed pins 3 from rotating or axially loosening under vibration conditions, ensuring connection reliability. Gantry hooks 8 are hinged to the four corners of the lifting device crossbeam 2 via the fork-shaped component 6. The upper end of the fork-shaped component 6 is hinged to the lifting device crossbeam 2 via the fixed pin 3; the lower end of the fork-shaped component 6 is hinged to the gantry hook 8 via the gantry hook pin 7. The four sets of gantry hooks 8 are symmetrically distributed.

[0018] Both sides of the upper part of the lifting beam 2 are equipped with pulley blocks 1. The centerline of the pulley blocks 1 is offset from the centerline of the corresponding side end of the lifting beam 2 along its length. The double-lifting-point structure formed by the two pulley blocks 1 can better distribute the load compared to a single lifting point, avoiding horizontal imbalance of the lifting equipment and improving the stability of the lifting process. Counterweight blocks 11 are symmetrically fixed at both ends of the lifting beam 2 near the pulley blocks 1, and are secured by fastening bolts 9. The mass and installation position of the counterweight blocks 11 are determined through precise mechanical calculations in the early stage. They can generate a stable balancing torque to counteract the eccentric torque caused by the change in the center of gravity of the intermediate package as it goes from empty to full. The counterweight blocks 11 are fixed to the lifting beam 2 by the fixing bolts 9, ensuring a firm connection and preventing displacement due to vibration during the lifting process. The symmetrical arrangement ensures the lifting equipment itself is balanced, further improving the stability of the lifting process.

[0019] A heat insulation plate 10 is installed at the lower end of the spreader beam 2. The heat insulation plate 10 is laid at the lower end of the spreader beam 2 and is made of a high-temperature resistant material with excellent heat insulation performance. Its coverage area corresponds to the high-temperature radiation area of ​​the tundish. Its function is to isolate the high temperature conducted by the tundish, avoid the degradation of material performance and lubrication failure of the spreader beam 2 and various metal connecting parts due to long-term exposure to high temperatures, extend the service life of the spreader, and reduce maintenance costs under high-temperature conditions.

[0020] Specifically, the lifting beam 2 is in the shape of an "I". The lifting beam 2 includes a longitudinal beam and a transverse beam. The transverse beams are symmetrically and vertically arranged at both ends of the longitudinal beams, and the longitudinal beams are offset from the center line of the transverse beams.

[0021] like Figure 1 As shown, a represents the center line of the lifting device, and b represents the center line of pulley block 1.

[0022] The method for setting up the integral eccentric beam lifting device for the intermediate tundish that requires no adjustment, as described in this application, includes the following steps: Step S1: Center of gravity trajectory modeling: For the eccentric tundish, establish a model of the change in center of gravity corresponding to different liquid level heights from the empty ladle state to the state of the maximum designed molten steel capacity. During the modeling process, it is crucial to analyze the dynamic shift of the center of gravity along the width of the lifting device under different molten steel levels, ensuring that the model comprehensively covers all actual lifting conditions. This step provides accurate foundational data for subsequent lifting point settings and counterweight calculations, preventing balance failures caused by missing center of gravity data and guaranteeing the accuracy and comprehensiveness of the data.

[0023] Step S2: Determine the theoretical suspension point: Analyze the center of gravity data from step S1, find the range of change of the center of gravity in the width direction [Y_min, Y_max], and take the center value of this range Y_center = (Y_min + Y_max) / 2 as the theoretical optimal suspension point center position; The logic behind setting this central position is to make it a "balance benchmark" for changes in the center of gravity under all operating conditions, minimizing the impact of center of gravity shift on the verticality of the hoisting under different liquid levels, and reducing the load requirement of counterweight 11. Its advantage lies in providing a reasonable benchmark for subsequent counterweight calculations by optimizing the hoisting point position, ensuring that counterweight 11 can achieve balance under all operating conditions with minimal mass.

[0024] Step S3: Calculate the counterweight parameters: Based on the principle of torque balance, establish a static model of the spreader-intermediate tundish system. Using the theoretical lifting point center Y_center as a reference, calculate the mass M_p of the fixed counterweight block and its installation position L_p that need to be applied to the other side of the spreader to balance the eccentric torque generated by the intermediate tundish at the Y_center position. The principle of the calculation formula is: M_p×g×L_p≈M_ladle×g×|Y_ladle-Y_center|; where M_p is the mass of counterweight block 11, L_p is the distance between the installation position of counterweight block 11 and the theoretical lifting point center, M_ladle is the maximum load mass of the intermediate tundish, Y_ladle is the center of gravity position of the intermediate tundish under maximum load, Y_center is the theoretical lifting point center position, and g is the acceleration due to gravity. Through precise mechanical calculation, the problem of blindly adjusting the counterweight block 11 is avoided.

[0025] Step S4: Lifting device assembly: Determine the eccentricity of pulley block 1 according to the center position of the lifting point in step S2, and set the counterweight block 11 at the designated position of the lifting device beam 2 according to the counterweight parameters in step S3.

[0026] This application takes the double tundish used in a ten-strand, ten-cup small billet continuous casting machine as an example: The first step was to measure the center of gravity width coordinate Y_empty = 120mm (biased towards the operating side) when the intermediate package was empty, and Y_full = 150mm when it was fully loaded. During this period, the center of gravity changed almost linearly between 120mm and 150mm as the liquid level changed.

[0027] The second step is to take the center value Y_center = (120 + 150) / 2 = 135 mm. Based on this, the eccentricity of the longitudinal beam of the lifting device's crossbeam 2 is calculated so that the center line of pulley block 1 is offset by 135 mm relative to the center of symmetry of the crossbeam.

[0028] The third step is to calculate the maximum load (ladle body + full molten steel) mass of the tundish, M_ladle = 80 tons. Using Y_center = 135mm as the target balance point, calculate the required balancing torque when the center of gravity is at the most unfavorable position, Y_full = 150mm. Calculations show that permanently installing a counterweight 11 with M_p = 600kg at the other end (drive side) of the spreader beam 2, at a distance L_p = 2000mm from the center, will ensure that the system's maximum tilt angle θ_max ≤ 2.1° under various liquid levels, far below the safety standard of 3°.

[0029] The fourth step involves manufacturing the lifting device according to these parameters, and welding and fixing the 600kg counterweight block 11 to both ends of the transmission side of the crossbeam. After the lifting device is put into use, whether lifting empty ladles, half-filled ladles, or full ladles, the lifting device and the tundish system can maintain a basically vertical state, the wire rope has no abnormal tilting, and no counterweight adjustment is required throughout the process, ensuring safety and efficiency.

[0030] The specific operating procedure is as follows: After the lifting equipment is assembled, it can be put into actual lifting operation: First, firmly connect the crane wire rope to the two sets of pulley blocks 1 of the lifting equipment to ensure that the wire rope is evenly stressed; then operate the crane to lower the lifting equipment and precisely align the four sets of gantry hooks 8 with the lifting lugs of the eccentric intermediate ladle. After confirming that the hooks are fully engaged, slowly raise the lifting equipment; during the lifting process, the lifting equipment, through the eccentric design of the pulley block 1 and the torque balancing effect of the counterweight block 11, counteracts the center of gravity shift of the intermediate ladle. Whether the intermediate ladle is empty, half-filled, or full, it can remain vertical and stable without the need for on-site counterweight adjustment; after the intermediate ladle is transferred to the target position, slowly lower it. After the intermediate ladle is stably placed, operate the lifting equipment to separate the gantry hooks 8 from the lifting lugs to complete one lifting operation.

[0031] This application, through precise mechanical calculations and structural design in the early stages, enables the lifting device to adapt to all working conditions of the tundish from empty to full after a single assembly. This solves the cumbersome problem of frequent counterweight adjustments required by existing lifting devices, significantly shortening preparation time and greatly improving operational efficiency. It is particularly suitable for emergency lifting scenarios, saving valuable time for production. The eccentric design of the pulley block 1 and the precise balance of the counterweight block 11 effectively counteract the center of gravity shift of the tundish, preventing tilting and swaying during lifting. Reliable connection and locking structures for each component strictly prevent the risk of loosening or displacement. The heat insulation plate 10 further enhances the long-term stability of the lifting device. The overall design significantly reduces the probability of major safety accidents such as molten steel leakage.

[0032] It should be noted that, unless otherwise expressly specified and limited, the term "connection" or its synonyms should be interpreted broadly in this document. For example, "connection" can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, expressions such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. At the same time, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In addition, the terms "front," "rear," "left," "right," "upper," and "lower" in this document refer to the placement states shown in the accompanying drawings.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A non-adjustable, integral eccentric beam lifting device for intermediate ballasts, characterized in that: It includes a lifting beam (2), a pulley block (1), a fork-shaped component (6), a gantry hook (8), and a counterweight (11); the four corners of the lifting beam (2) are all hinged with gantry hooks (8) through the fork-shaped component (6); the upper two sides of the lifting beam (2) are provided with pulley blocks (1), and the center line of the pulley blocks (1) is offset from the center line of the length direction of the corresponding side end of the lifting beam (2); the counterweight (11) is symmetrically fixed at both ends of the lifting beam (2) near the pulley block (1).

2. The integral eccentric beam lifting device for intermediate tundish that requires no adjustment according to claim 1, characterized in that: The four corners of the lifting beam (2) are respectively provided with mounting holes, and a fixing pin (3) is fitted through the mounting holes. The upper end of the fork-shaped part (6) is hinged to the lifting beam (2) through the fixing pin (3).

3. The integral eccentric beam lifting device for intermediate tundish that requires no adjustment according to claim 2, characterized in that: The lower end of the fork-shaped part (6) is hinged to the gantry hook (8) through the gantry hook pin (7), and the four sets of gantry hooks (8) are symmetrically distributed.

4. The integral eccentric beam lifting device for intermediate tundish that requires no adjustment according to claim 3, characterized in that: Both ends of the fixed pin (3) are provided with fixed plates (5), and the fixed plates (5) are fixedly connected to the lifting beam (2) by fixing bolts (4).

5. The integral eccentric beam lifting device for intermediate tundish that requires no adjustment according to claim 1, characterized in that: A heat insulation plate (10) is provided at the lower end of the lifting beam (2).

6. The integral eccentric beam lifting device for intermediate tundish that requires no adjustment according to claim 1, characterized in that: The counterweight (11) is fixed by fastening bolts (9).

7. A method for setting up an integral eccentric beam lifting device for a tundish that requires no adjustment, characterized in that: Based on the lifting device according to any one of claims 1-5, the following steps are included: Step S1: Center of gravity trajectory modeling: For the eccentric tundish, establish a model of the change in center of gravity corresponding to different liquid level heights from the empty state to the state of the maximum designed molten steel capacity; Step S2: Determine the theoretical suspension point: Analyze the center of gravity data from step S1, find the range of variation of the center of gravity in the width direction [Y_min, Y_max], and take the center value of this range Y_center = (Y_min + Y_max) / 2 as the theoretical optimal suspension point center position; Step S3: Calculate the counterweight parameters: Based on the principle of torque balance, establish a static model of the spreader-intermediate bag system. With the theoretical lifting point center Y_center as a reference, calculate the mass M_p of the fixed counterweight block and its installation position L_p that need to be applied on the other side of the spreader to balance the eccentric torque generated by the intermediate bag at the Y_center position through the calculation formula. Step S4: Lifting device assembly: Determine the eccentricity of the pulley block (1) according to the center position of the lifting point in step S2, and set the counterweight block (11) at the specified position on the lifting device beam (2) according to the counterweight parameters in step S3.

8. The method for setting up the integral eccentric beam lifting device for the intermediate tundish that requires no adjustment according to claim 7, characterized in that: In step S3, the principle of the calculation formula is: M_p×g×L_p≈M_ladle×g×|Y_ladle-Y_center|; where M_p is the mass of the counterweight (11), L_p is the distance between the installation position of the counterweight (11) and the theoretical lifting point center, M_ladle is the maximum load mass of the intermediate bag, Y_ladle is the center of gravity position of the intermediate bag under maximum load, Y_center is the theoretical lifting point center position, and g is the gravitational acceleration.

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