A reactor coolant shield motor pump main bolt hot stretching apparatus

Abstract

The application discloses a reactor coolant shielding motor pump main bolt hot stretching equipment and relates to the technical field of nuclear reactor equipment. The equipment comprises a moving vehicle seat, a lifting platform, a stretching mechanism and a translation drive. The moving vehicle seat is used for driving the equipment to move to the motor pump to perform hot stretching on the main bolt of the motor pump. The lifting platform is arranged on the moving vehicle seat and is used as a mounting support main body of the stretching equipment. The stretching mechanism is used for performing hot stretching on the main bolt of the motor pump. The translation drive is arranged on the upper end of the lifting platform and is used for driving the stretching mechanism to move horizontally close to the motor pump body. The stretching mechanism comprises a fixed arc-shaped seat fixedly arranged on the translation drive. A rotary drive is slidably arranged on the fixed arc-shaped seat. A movable arc-shaped seat is slidably connected to the rotary drive. A plurality of heating jacking mechanisms for controlling the lifting insertion of heating rods into the main bolt to perform hot stretching are mounted on the movable arc-shaped seat. The application ensures the uniform heating of the main bolt, thereby improving the sealing performance and long-term operation stability of the motor pump connecting structure.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor equipment technology, specifically to a hot stretching device for the main bolts of a reactor coolant shielded motor pump. Background Technology

[0002] In nuclear reactor cooling systems, the connection structure of reactor coolant shielded motor pumps commonly uses bolt connections instead of welding. The bolt installation process must strictly adhere to torque specifications. Its core principle is to apply precise torque to induce controllable elongation of the bolts, which, combined with gasket deformation, achieves reliable sealing and uniform stress distribution at the connection points. In the hot-stretching process, the main bolts expand thermally after heating, increasing their length. This creates a gap between the main nut and the pump body. Tightening the main nut eliminates this gap, allowing the bolts to maintain a preset elongation after cooling, thus ensuring uniform locking force in the circumferential direction. However, this process faces several technical obstacles: the existence of a small compressible gap between the motor pump body and the pump casing, the inherent differences in the physical properties of the bolt materials, and the randomness of the stretching sequence all make it difficult to maintain consistent actual elongation after a single stretch of each main bolt. More seriously, the circular array of main bolts generates heat conduction effects during heating, and the temperature field interference between adjacent bolts further exacerbates the uneven elongation, directly affecting the overall sealing performance and long-term operational stability of the connection structure.

[0003] The thermal stretching of the main bolts of the existing reactor coolant shielded motor pump is as follows: Figure 8 As shown, the main bolt 300 has a heating hole on its axis for the heating rod 500 to extend into. The main bolt 300 is threaded through the threaded hole on the pump housing 100 and then inserted into the pump body 200. It is then initially locked by the main nut 400. After the initial locking, the heating rod 500 is inserted into the heating hole of the main bolt 300. The main bolt 300 expands and lengthens due to heating. At this time, a gap A is created between the main nut 400 and the lower end of the pump body 200. Then, the main nut 400 is screwed until it fits tightly with the lower end of the pump body 200 to complete the shaping of the stretched main bolt 300. The fixed installation between the pump body 200 and the pump housing 100 is completed through multiple heating and stretching processes.

[0004] Current hot stretching operations rely entirely on manual labor, requiring operators to insert heating rods one by one into the heating holes of the main bolts distributed around the pump body. Because the main bolts are densely arranged circumferentially, manual operation not only necessitates repeated adjustments to position and angle but is also limited by confined working spaces, resulting in excessively long insertion times and inconsistent accuracy. This inefficient manual method cannot meet the requirements for simultaneous or sequential processing of multiple bolts, easily leading to overheating or underheating of some bolts and disrupting the uniform distribution of circumferential locking force. In the high-precision installation scenario of nuclear reactors, such operational defects significantly reduce the assembly quality of the motor pump, extend the project cycle, and may create safety hazards such as seal failure or stress concentration. Therefore, there is an urgent need to develop a specialized device capable of adapting to the annular array structure and achieving efficient and stable hot stretching to solve the efficiency bottlenecks and quality fluctuations caused by manual operation. Summary of the Invention

[0005] The purpose of this invention is to provide a hot stretching device for the main bolts of reactor coolant shielded motor pumps, which solves the technical problem that in the process of connecting the main bolts of reactor coolant shielded motor pumps, the heating rod is manually inserted into the heating hole of the main bolt, which is inefficient and makes it difficult to ensure the consistency of the locking force in the circumferential direction.

[0006] The objective of this invention can be achieved through the following technical solutions: A device for hot-stretching reactor coolant shielded motor pump main bolts, comprising: The moving seat, whose drive unit moves to the motor pump, has its main bolts subjected to thermal stretching. The lifting platform is set on the mobile carriage and serves as the main support for the installation of the stretching equipment. A tensioning mechanism, used for thermal stretching of the main bolts of the motor pump; The translation drive is located at the upper end of the lifting platform and is used to drive the tensioning mechanism to move horizontally closer to the motor pump body. The stretching mechanism includes a fixed arc-shaped seat fixedly mounted on a translation drive, a rotary drive slidably mounted on the fixed arc-shaped seat, a movable arc-shaped seat slidably connected to the rotary drive, and multiple heating lifting mechanisms for controlling the raising and lowering of the heating rod to be inserted into the main bolt for thermal stretching are installed on the movable arc-shaped seat.

[0007] Preferably, a push-pull handle for moving the device is fixedly provided on one side of the mobile seat, and a vehicle body lifting mechanism for driving the lifting platform to move up and down is provided at the upper end of the mobile seat. The lifting platform moves up and down, driving the stretching mechanism to move up and down close to the main bolt for thermal stretching.

[0008] Preferably, the translation drive includes two sets of platform plates fixedly mounted on the upper end of the lifting platform, a translation screw rotatably mounted between the two sets of platform plates, and a translation guide rod fixedly mounted therebetween. A translation motor for driving the translation screw to rotate is fixedly mounted on one set of platform plates. A translation slide is threadedly connected to the translation screw and the translation slide is slidably connected to the translation guide rod. The tensioning mechanism is fixedly mounted on the translation slide.

[0009] Preferably, the translation slide has a U-shaped plate structure, with its vertical end threaded through and mounted on the translation lead screw and slidably connected to the translation guide rod. Its horizontal plate can extend out of the end of the lifting platform, thereby completely separating the tensioning mechanism from the lifting platform and avoiding interference between the lifting platform and the outer peripheral protrusion of the motor pump during the hot stretching treatment of the main bolt.

[0010] Preferably, the fixed arc-shaped seat includes an arc-shaped guide plate fixedly mounted on a translation slide, the upper outer periphery of the arc-shaped guide plate is provided with guide teeth, the upper inner periphery of the arc-shaped guide plate is fixedly provided with a limiting inner guide plate, and the rotation drive is slidably connected to the guide teeth.

[0011] Preferably, the rotary drive includes a drive main board slidably disposed on the upper end of the arc-shaped guide plate. One side of the drive main board is provided with a guide plate sleeve that slides and engages with the inner guide plate. A bracket is fixedly disposed at the lower end of the other side of the drive main board. A motor is fixedly disposed at the lower end of the bracket. A gear that meshes with the guide external gear is fixedly mounted on the output shaft of the motor. A limit guide rail is fixedly disposed at the upper end of the drive main board. A movable arc-shaped seat is slidably disposed at the limit guide rail.

[0012] Preferably, a second bracket is fixedly installed on the upper end of the side of the drive motherboard near the first bracket, and a vertically downward motor is fixedly installed on the upper end of the second bracket. The output end of the second motor is fixedly connected to a gear for driving the movable arc-shaped seat to slide along the limiting guide rail.

[0013] Preferably, the movable arc-shaped seat includes a limiting slide that is slidably disposed on the limiting guide rail. Both ends of the limiting slide are provided with limiting end plates for sliding limiting. The upper end of the limiting slide is fixedly provided with an arc-shaped top plate for installing a heating lifting mechanism. The outer periphery of the arc-shaped top plate is fixedly provided with a plurality of driving external teeth that mesh with the gear. When it is necessary to perform hot stretching on the main bolts of the motor pump, since the main bolts are distributed in a circular array on the outer circumference of the motor pump, hot stretching of the main bolts at different positions around the circumference is achieved by moving the movable arc-shaped seat. First, the movable arc-shaped seat and the fixed arc-shaped seat are in the vertically overlapping position. At this time, multiple main bolts in the semi-circular position on the side of the motor pump closer to the fixed arc-shaped seat are hot stretched. Then, the rotary drive moves towards the left side of the fixed arc-shaped seat to the left end. Then, the rotary drive drives the movable arc-shaped seat to continue moving towards the left side of the fixed arc-shaped seat, so that the movable arc-shaped seat extends beyond the left side of the fixed arc-shaped seat. This achieves hot stretching of multiple main bolts in the left quarter-circle position on the side of the motor pump away from the fixed arc-shaped seat. Then, the rotary drive moves towards the right side of the fixed arc-shaped seat to the right end. Then, the rotary drive drives the movable arc-shaped seat to continue moving towards the right side of the fixed arc-shaped seat, so that the movable arc-shaped seat extends beyond the right side of the fixed arc-shaped seat. This achieves hot stretching of multiple main bolts in the right quarter-circle position on the side of the motor pump away from the fixed arc-shaped seat. Thus, hot stretching of several main bolts around the complete circumference of the motor pump is achieved.

[0014] Preferably, the heating lifting mechanism includes a fixed upright plate fixedly mounted on the upper end of the arc-shaped top plate, an electric telescopic cylinder fixedly mounted on the fixed upright plate, a connecting plate fixedly connected to the output end of the electric telescopic cylinder, a connecting top plate fixedly connected to the upper end of the connecting plate, a through hole for the heating rod to pass through on the connecting top plate, a pressing side plate fixedly mounted on the end of the connecting top plate away from the connecting plate, a pump body arc-shaped groove fitted to the outer periphery of the motor pump on the pressing side plate, and a lifting component for driving the heating rod to move up and down on the side of the pump body arc-shaped groove near the connecting plate.

[0015] Preferably, the lifting assembly includes a lifting base plate fixedly disposed on the lower part of the top pressure side plate, a lifting screw rotatably disposed between the lifting base plate and the connecting top plate, a lifting motor for driving the lifting screw to rotate is fixedly disposed at the lower end of the lifting base plate, a screw slide is threaded through the lifting screw, one end of the screw slide is slidably attached to the side wall of the top pressure side plate, and the heating rod is fixedly disposed on the screw slide.

[0016] The beneficial effects of this invention are as follows: the moving device is driven by the moving seat, and the lifting platform supports the stretching mechanism. The stretching mechanism includes a movable arc-shaped seat and a heating and lifting mechanism to achieve automatic heating at multiple positions, thereby efficiently and uniformly stretching the main bolts of the annular array. This improves the efficiency and accuracy of the hot stretching operation, ensures uniform heating of the main bolts, and thus enhances the sealing performance and long-term operational stability of the motor-pump connection structure. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1This is a three-dimensional structural diagram of the entire invention; Figure 2 This is an isometric structural schematic diagram of the entire invention; Figure 3 This is a three-dimensional structural schematic diagram of the stretching mechanism of the present invention; Figure 4 This is an isometric structural schematic diagram of the tensioning mechanism of the present invention; Figure 5 This is a top view of the tensioning mechanism of the present invention. Figure 6 This is the present invention. Figure 5 Schematic diagram of the cross-sectional structure in the middle BB direction; Figure 7 This is a schematic diagram of the heating and lifting mechanism of the present invention; Figure 8 This is a schematic diagram of the thermal stretching of the main bolts of the existing reactor coolant shielded motor pump.

[0019] In the diagram: 1. Movable seat; 2. Push-pull handlebars; 3. Body lifting mechanism; 4. Lifting platform; 5. Translation drive; 51. Platform upright; 52. Translation motor; 53. Translation lead screw; 54. Translation guide rod; 55. Translation slide; 6. Fixed arc-shaped seat; 61. Arc-shaped guide plate; 62. Guide external gear; 63. Limiting inner guide plate; 7. Rotation drive; 71. Drive main board; 72. Guide plate sleeve; 73. Bracket 1; 74. Bracket 2; 75. Motor 1; 7 6. Gear 1; 77. Motor 2; 78. Gear 2; 79. Limiting guide rail; 8. Movable arc-shaped seat; 81. Limiting slide; 82. Arc-shaped top plate; 83. Limiting end plate; 84. Drive external gear; 9. Heating lifting mechanism; 91. Fixed upright plate; 92. Electric telescopic cylinder; 93. Connecting plate; 94. Connecting top plate; 95. Top pressure side plate; 95. Pump body arc-shaped groove; 96. Lifting base plate; 97. Lifting screw; 98. Lifting motor; 99. Screw slide; 100, Pump casing; 200, Pump body; 300, Main bolt; 400, Main nut; 500, Heating rod. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] The traditional method of connecting the main bolts of reactor coolant shielded motor pumps requires thermal stretching of the main bolts during installation. However, since the main bolts are arranged in a ring array around the pump's circumference, the current method involves manually inserting heating rods into the heating holes of the main bolts. This single-insertion method is inefficient and makes it difficult to ensure consistent tightening force in the circumferential direction, thus affecting the overall installation quality and reliability of the motor pump.

[0022] For this, please refer to Figures 1-7 As shown, this application proposes a hot stretching device for the main bolts of a reactor coolant shielded motor pump. By configuring a movable carriage 1, a lifting platform 4, a translation drive 5, and a stretching mechanism, the device achieves flexible positioning and precise adjustment around the motor pump. The stretching mechanism includes a fixed arc-shaped seat 6, a rotary drive 7, a movable arc-shaped seat 8, and multiple heating and lifting mechanisms 9, enabling automated, efficient, and stable hot stretching of the main bolts distributed in a ring array, effectively improving installation efficiency and quality.

[0023] This embodiment provides a device for hot stretching the main bolts of a reactor coolant shielded motor pump.

[0024] The device includes a movable carriage 1, which drives the device to the motor pump for thermal stretching of its main bolts. Alternatively, the movable carriage 1 can be a wheeled platform, allowing the device to be moved manually or by a simple motor drive.

[0025] The lifting platform 4 is mounted on the movable carriage 1, serving as the main support for the installation of the stretching equipment. The lifting platform 4 can adopt a scissor-type structure, and its lifting and lowering can be achieved by a manual crank or a simple hydraulic cylinder to adjust the height of the stretching mechanism.

[0026] The tensioning mechanism is used for the thermal tensioning of the main bolts of the motor pump. The tensioning mechanism can be a modular unit that integrates heating, positioning, and lifting functions.

[0027] The translation drive 5 is located at the upper end of the lifting platform 4 and is used to drive the tensioning mechanism to move horizontally closer to the motor pump body. The translation drive 5 can consist of a simple lead screw and guide rail. The tensioning mechanism can be moved horizontally by manually rotating the lead screw or by a general-purpose motor driving the lead screw to rotate.

[0028] The tensioning mechanism includes a fixed arc-shaped seat 6 fixedly mounted on the translation drive 5. The fixed arc-shaped seat 6 can be a plate-like structure with an arc-shaped profile, fixed to the moving part of the translation drive 5 by bolts or welding, providing a foundation for subsequent rotation and movement.

[0029] A rotary drive 7 is slidably mounted on the fixed arc-shaped base 6. The rotary drive 7 can be a ring structure with a slider, which slides by cooperating with the guide groove on the fixed arc-shaped base 6, and can be rotated manually or by a motor through a friction wheel to rotate along the arc-shaped path.

[0030] A movable arc-shaped seat 8 is slidably connected to the rotary drive 7. The movable arc-shaped seat 8 can be an arc-shaped plate connected to the rotary drive 7 via a slide rail, which can slide on the rotary drive 7 by manual pushing or pulling or by a motor meshing with a rack on the movable arc-shaped seat 8 via gears.

[0031] Multiple heating lifting mechanisms 9 are installed on the movable arc-shaped base 8 to control the lifting and lowering of the heating rod 500 and its insertion into the main bolt for thermal stretching. The heating lifting mechanism 9 can be composed of a simple pneumatic cylinder or hydraulic cylinder, and its output end is connected to a component that clamps the heating rod 500. The lifting and lowering of the heating rod 500 is achieved by controlling the extension and retraction of the pneumatic cylinder or hydraulic cylinder.

[0032] Through the above technical solution, this equipment can achieve automated and efficient thermal stretching of the main bolts of the reactor coolant shielded motor pump. The coordinated action of the moving carriage 1, the lifting platform 4, and the translation drive 5 enables the equipment to flexibly position and precisely adjust to the main bolt location. The combination of the fixed arc-shaped seat 6, the rotary drive 7, and the movable arc-shaped seat 8 in the stretching mechanism allows the equipment to adapt to the annular array distribution of the main bolts, enabling continuous operation on main bolts at different positions. The heating and lifting mechanism 9 ensures that the heating rod 500 can be stably and accurately inserted into the main bolt for heating, thereby effectively solving the problems of low efficiency and uneven stretching in traditional manual operation, and improving the installation quality and reliability of the motor pump.

[0033] In some of the embodiments described above in this application, a movable carriage is proposed to drive the equipment to the motor pump. However, in its implementation, the equipment movement and lifting adjustment may be inefficient and inconvenient to operate, requiring manual pushing and manual height adjustment, which affects the accuracy and overall efficiency of thermal stretching.

[0034] In response, this application further proposes a hot stretching device for the main bolt of a reactor coolant shielded motor pump. A push-pull handle 2 for pushing the device is fixedly installed on one side of the moving seat 1. A vehicle lifting mechanism 3 for driving the lifting platform 4 to move up and down is installed at the upper end of the moving seat 1. The lifting platform 4 moves up and down, driving the stretching mechanism to move up and down close to the main bolt for hot stretching.

[0035] Through the above technical solution, since a push-pull handle 2 is fixedly installed on one side of the mobile carriage 1, the operator can easily push the equipment manually to move it to the motor pump, significantly improving the equipment's movement efficiency and operational convenience, and avoiding the inconvenience of moving equipment in the traditional way. Simultaneously, the vehicle body lifting mechanism 3 installed at the upper end of the mobile carriage 1 can drive the lifting platform 4 to move up and down, thereby driving the overall lifting of the stretching mechanism, achieving automated and precise adjustment of the equipment height. This allows the stretching mechanism to accurately align with the main bolt of the motor pump, avoiding errors that may be caused by manual adjustment, and greatly improving the accuracy and stability of the hot stretching operation. Overall, this application, by introducing the push-pull handle 2 and the vehicle body lifting mechanism 3, effectively solves the problems of low efficiency and inconvenient operation in equipment movement and lifting adjustment, ensuring the accuracy and efficiency of the hot stretching process, thereby improving the overall quality of the hot stretching of the motor pump's main bolt.

[0036] In some of the embodiments described above in this application, a translation drive is proposed to drive the stretching mechanism to move horizontally closer to the motor pump body. However, in its implementation, the translation drive structure may lack precise guidance and stable support, which may cause the stretching mechanism to sway or deviate during the movement, affecting the accuracy and efficiency of the hot stretching operation, and thus failing to ensure the uniform elongation of the main bolt.

[0037] In response, this application further proposes a method for implementing translation drive, specifically including: the translation drive 5 includes two sets of platform uprights 51 fixedly mounted on the upper end of the lifting platform 4. These two sets of platform uprights 51 serve as the basic support structure of the translation drive 5, effectively enhancing the overall rigidity and preventing tilting or deformation during the movement of the tensioning mechanism.

[0038] Between the two sets of platform plates 51, a translation screw 53 is rotatably mounted, and a translation guide rod 54 is fixedly mounted. The translation screw 53 is mainly responsible for converting rotational motion into linear displacement of the tensioning mechanism, ensuring its precise horizontal movement. This translation screw 53 can be a ball screw, where the rolling of balls between the screw and nut effectively reduces friction, thereby improving transmission efficiency and positioning accuracy; alternatively, a trapezoidal screw can be used, which has a relatively simple structure and low cost, suitable for applications where the precision requirements are not extremely high but stable transmission is still necessary. The translation guide rod 54 works in conjunction with the translation screw 53, providing stable sliding constraints for the horizontal movement of the tensioning mechanism, ensuring the straightness and stability of its movement trajectory. This translation guide rod 54 can be a precision linear guide, such as a cylindrical linear guide or a square linear guide, with a corresponding slider to provide high-precision linear motion; alternatively, a simple guide rod such as an optical axis can be used with a sliding bearing to provide basic linear guidance.

[0039] One of the platform plates 51 is fixedly equipped with a translation motor 52 for driving the translation screw 53 to rotate. This translation motor 52, as the power source for the translation drive 5, provides controllable power to achieve precise rotation control of the translation screw 53. The translation motor 52 can be a stepper motor, which achieves precise control of the rotation angle and position of the translation screw 53 through precise control pulse signals; alternatively, a servo motor can be used in conjunction with an encoder to achieve closed-loop control, thereby providing higher accuracy, response speed, and torque output.

[0040] A translation slide 55 is threadedly connected to the translation screw 53, and this translation slide 55 is slidably connected to the translation guide rod 54. The translation slide 55 is a key component supporting the tensioning mechanism. Through its threaded connection with the translation screw 53, it converts the rotational motion of the translation screw 53 into its own linear movement; simultaneously, through its slidable connection with the translation guide rod 54, it further restricts its degrees of freedom, effectively preventing swaying during movement. The translation slide 55 can be designed with an internally integrated nut that threadedly engages with the translation screw 53, and an externally fitted linear bearing or slider that engages with the translation guide rod 54; alternatively, it can be a single casting with threaded holes and guide holes machined on it for connection with the translation screw 53 and the translation guide rod 54, respectively. The tensioning mechanism is fixedly mounted on the translation slide 55, thus enabling precise horizontal movement along with the translation slide 55. The tensioning mechanism can be directly fixed to the mounting surface of the translation slide 55 using fasteners such as bolts; alternatively, it can be connected using structures such as dovetail grooves or T-slots to facilitate quick installation and disassembly.

[0041] Through the above technical solution, this application effectively solves the problems of insufficient precise guidance and stable support that may exist in translation drive during movement. Specifically, the two sets of platform plates 51 provide a solid structural foundation for the entire translation drive 5, enhancing its overall rigidity. The synergistic effect of the translation screw 53 and the translation guide rod 54 constructs a dual guiding mechanism. The translation screw 53 is responsible for accurately converting the rotational power of the translation motor 52 into the linear displacement of the tensioning mechanism, while the translation guide rod 54 provides stable sliding constraints, ensuring that the tensioning mechanism always maintains a straight trajectory during horizontal movement, avoiding swaying or deviation. The translation motor 52, as a controllable power source, can achieve precise control of the movement speed and position of the tensioning mechanism. The translation slide 55, as a bridge connecting the translation screw 53, the translation guide rod 54, and the tensioning mechanism, ensures the stability and positional accuracy of the tensioning mechanism during movement. Therefore, the stretching mechanism can move horizontally and precisely towards the motor pump body along a preset trajectory and position, thus laying a solid foundation for the subsequent precise insertion of the heating rods 500 by the heating lifting mechanism 9 and the hot stretching operation of the main bolts. This precise and stable translational capability significantly improves the accuracy and efficiency of the hot stretching operation, ensuring uniform elongation when the main bolts of the motor pump are hot stretched, thereby guaranteeing the tightness and uniformity of the motor pump installation and effectively improving the overall installation quality of the equipment.

[0042] In some of the embodiments described above in this application, a translation slide is proposed to drive the stretching mechanism to move horizontally closer to the motor pump body. However, in its implementation, the lifting platform may interfere with the outer peripheral protrusion of the motor pump, affecting the stability and efficiency of the hot stretching operation.

[0043] In this regard, this application further proposes that the translation slide 55 has a U-shaped plate structure, with its vertical end threaded through and installed on the translation lead screw 53 and slidably connected to the translation guide rod 54. Its horizontal plate can extend out of the end of the lifting platform 4, thereby completely separating the tensioning mechanism from the lifting platform 4 and avoiding interference between the lifting platform 4 and the outer peripheral protrusion of the motor pump during the hot stretching treatment of the main bolt.

[0044] Specifically, the L-shaped plate structure used in the translation slide 55 is a plate-like structure with L-shaped or right-angle bends, typically comprising a vertical section and a horizontal section. This structural design aims to provide a specific spatial layout and mechanical support, enabling it to cross or avoid certain obstacles while maintaining connection with the drive mechanism. For example, its vertical section can be used to connect the drive mechanism, while the horizontal section can extend to a specific area. This L-shaped structure can be formed by integral molding, welding, or bolting, and the material can be high-strength alloy steel or aluminum alloy to ensure its structural stability when bearing the weight of the tension mechanism and motion loads.

[0045] The vertical end of the translation slide 55 is threaded through and mounted on the translation lead screw 53, and is slidably connected to the translation guide rod 54. This connection ensures that when the translation motor 52 drives the translation lead screw 53 to rotate, the translation slide 55 can move precisely in a straight line along the lead screw axis. At the same time, the sliding connection with the translation guide rod 54 provides additional guidance and support, effectively preventing the translation slide 55 from deflecting or wobbling during movement, thereby ensuring the smooth and accurate horizontal movement of the tensioning mechanism.

[0046] Furthermore, the horizontal plate of the translation slide 55 can extend beyond the end of the lifting platform 4. This design allows the mounting base of the tensioning mechanism to extend beyond the physical boundary of the lifting platform 4 during horizontal movement, pushing the tensioning mechanism closer to the motor pump body. This design cleverly solves the problem that the lifting platform 4 itself cannot get sufficiently close to the motor pump body due to size or structural limitations. The length and shape of the horizontal plate can be optimized according to the specific structure of the motor pump body and the protruding parts that need to be avoided. For example, it can be designed as a telescopic structure, or through modular design, different lengths of horizontal plates can be replaced according to actual needs.

[0047] Through the above technical solution, when the translation slide 55 moves horizontally under the drive of the translation screw 53 and the translation guide rod 54, the tensioning mechanism moves accordingly. Due to the extension of the horizontal plate of the translation slide 55, the tensioning mechanism can get closer to the motor pump body, while the lifting platform 4 remains at a safe distance, thus achieving spatial "disengagement" between the tensioning mechanism and the lifting platform 4. This design cleverly solves the spatial interference problem between the lifting platform 4 and the protruding parts on the outer periphery of the motor pump, ensuring that the tensioning mechanism can stably and accurately position itself at the main bolt position, significantly improving the reliability of the hot tensioning operation. At the same time, it avoids additional adjustments or avoidance operations, simplifies the equipment deployment process, and thus improves work efficiency. Furthermore, this solution enhances the versatility and applicability of the equipment, enabling it to adapt to different models or motor pumps with complex shapes, and effectively reduces the risk of collision between the equipment and the motor pump body, protecting the integrity of both the equipment and the motor pump body.

[0048] In some of the embodiments described above in this application, a fixed arc-shaped seat is proposed to support the rotation drive. However, in its implementation, the lack of an effective guiding and limiting structure may lead to uneven sliding or inaccurate positioning, affecting the uniformity and efficiency of thermal stretching.

[0049] In response, this application further proposes a hot stretching device for the main bolt of a reactor coolant shielded motor pump, wherein the fixed arc-shaped seat 6 includes an arc-shaped guide plate 61 fixedly mounted on a translation slide 55, the upper outer periphery of the arc-shaped guide plate 61 is provided with guide teeth 62, the upper inner periphery of the arc-shaped guide plate 61 is fixedly provided with a limiting inner guide plate 63, and the rotary drive 7 is slidably connected to the guide teeth 62.

[0050] Specifically, the fixed arc-shaped seat 6, as a key component of the tensioning mechanism, primarily functions to provide a stable support base with a specific arc-shaped trajectory for the rotary drive 7. By being securely mounted on the translation slide 55, the fixed arc-shaped seat 6 ensures the stability of the entire rotary mechanism after horizontal translation, laying a solid foundation for subsequent rotation and heating lifting operations.

[0051] The arc-shaped guide plate 61 is the core structure of the fixed arc-shaped seat 6. It is arc-shaped and fixedly mounted on the translation slide 55. The function of the arc-shaped guide plate 61 is to provide a preset and precise arc-shaped motion trajectory for the rotary drive 7.

[0052] The guide gear 62 is located on the upper outer periphery of the arc-shaped guide plate 61. The main function of the guide gear 62 is to mesh with the corresponding gear (e.g., gear 76) on the rotary drive 7, thereby achieving precise guidance and drive of the rotary drive 7. The guide gear 62 can adopt various tooth profiles such as spur teeth, helical teeth, or herringbone teeth to adapt to different transmission requirements and load-bearing capacities, ensuring smooth, backlash-free sliding of the rotary drive 7 on the arc-shaped trajectory.

[0053] The inner guide plate 63 is fixedly mounted on the upper inner circumference of the arc-shaped guide plate 61. The function of this inner guide plate 63 is to provide radial limiting support for the rotary drive 7, preventing radial displacement or deviation from the preset trajectory during sliding. The inner guide plate 63 can be designed as a smooth arc-shaped flange, groove, or guide rail structure, cooperating with the guide plate sleeve 72 on the rotary drive 7 to ensure stable sliding of the rotary drive 7 on the arc-shaped guide plate 61.

[0054] The rotary drive 7 is slidably connected to the guide external gear 62, which means that the rotary drive 7 can move smoothly along the arc-shaped trajectory defined by the arc-shaped guide plate 61. This sliding connection achieves precise positioning and driving through the meshing of the guide external gear 62 and the drive gear on the rotary drive 7, while the limiting inner guide plate 63 provides additional radial constraint, ensuring the stability and reliability of the movement.

[0055] Through the above technical solution, the fixed arc-shaped seat 6, through the synergistic action of its arc-shaped guide plate 61, guide external teeth 62, and limiting inner guide plate 63, provides a structurally stable, precisely guided, and effectively limiting sliding platform for the rotary drive 7. The meshing of the guide external teeth 62 with the rotary drive 7 ensures the precise driving and positioning of the rotary drive 7 on the arc-shaped trajectory, effectively avoiding instability and inaccurate positioning during the sliding process. At the same time, the limiting inner guide plate 63 effectively constrains the radial offset of the rotary drive 7, further improving the stability and reliability of the motion. This design enables the tensioning mechanism to perform hot stretching on the main bolts of the motor pump with higher precision and stability, thereby ensuring the uniformity and efficiency of the hot stretching operation and ultimately improving the installation quality of the motor pump.

[0056] In some of the solutions described above in this application, a rotary drive is proposed to slide on a fixed arc-shaped seat to drive the movable arc-shaped seat to move. However, in this process, the sliding of the rotary drive may be unstable or inaccurate, resulting in inaccurate movement of the movable arc-shaped seat, which in turn affects the efficiency and accuracy of inserting the heating rod into the main bolt.

[0057] In response, this application further proposes a hot stretching device for the main bolt of a reactor coolant shielded motor pump. The rotary drive 7 includes a drive main board 71 slidably disposed on the upper end of an arc-shaped guide plate 61. A guide plate sleeve 72 is disposed on one side of the drive main board 71 and slidably engages with the inner guide plate 63. A bracket 73 is fixedly disposed on the lower end of the other side of the drive main board 71. A motor 75 is fixedly disposed on the lower end of the bracket 73. A gear 76 that meshes with the guide external gear 62 is fixedly mounted on the output shaft of the motor 75. A limit guide rail 79 is fixedly disposed on the upper end of the drive main board 71, and a movable arc-shaped seat 8 is slidably disposed at the limit guide rail 79.

[0058] Through the above technical solution, the drive main board 71 slides stably on the arc-shaped guide plate 61. The cooperation between the guide plate sleeve 72 and the limiting inner guide plate 63 effectively prevents lateral displacement, ensuring the precise motion trajectory of the rotary drive 7. The motor 75 provides a stable and controllable driving force through the meshing of the gear 76 and the guide external gear 62, accurately converting the rotational motion into arc-shaped displacement, avoiding the jamming or slippage that may occur with traditional sliding. At the same time, the limiting guide rail 79 provides reliable linear guidance for the movable arc-shaped seat 8, enabling the movable arc-shaped seat 8 to be precisely positioned and adjusted on the drive main board 71. Overall, this structure significantly improves the sliding stability and positioning accuracy of the rotary drive 7, thereby ensuring that the movable arc-shaped seat 8 can accurately move to the target position, thus improving the efficiency and accuracy of the heating rod 500 inserting into the main bolt, and effectively solving the problem of inaccurate movement of the movable arc-shaped seat caused by unstable or inaccurate rotary drive sliding.

[0059] In some of the embodiments described above in this application, a rotary drive is proposed to drive the movable arc seat to move. However, in its implementation, the sliding of the movable arc seat may lack stability and precise control, resulting in low efficiency of the thermal stretching operation of the main bolts at different positions on the outer periphery of the motor pump, affecting the uniformity and reliability of the overall installation.

[0060] In this regard, this application further proposes that a second bracket 74 is fixedly installed on the upper end of the drive motherboard 71 near the first bracket 73, and a vertically downward motor 77 is fixedly installed on the upper end of the second bracket 74. The output end of the second motor 77 is fixedly connected to a gear 78 for driving the movable arc-shaped seat 8 to slide along the limiting guide rail 79.

[0061] Through the above technical solution, a second bracket 74 is added to the drive main board 71, and a vertically downward motor 77 is fixedly installed on this second bracket 74. The output end of the second motor 77 meshes with the movable arc-shaped seat 8 through a gear 78. This design makes the sliding of the movable arc-shaped seat 8 no longer rely solely on sliding friction or indirect drive, but achieves precise and stable linear movement through a gear transmission mechanism. Given that gear transmission has advantages such as accurate transmission ratio, smooth transmission, and large load-bearing capacity, it can effectively overcome problems such as jamming, shaking, or inaccurate positioning that may occur during the sliding of the movable arc-shaped seat 8, thereby significantly improving the stability and precise control capability of the movable arc-shaped seat 8 on the limit guide rail 79. Because the movable arc-shaped seat 8 can be precisely and stably positioned, the heating and lifting mechanism 9 installed on it can more accurately perform hot stretching operations on the main bolts distributed in the annular array around the motor pump, ensuring the positional accuracy and consistency of the effect of each hot stretching operation. This not only improves the efficiency of hot stretching operations, but more importantly, it ensures the uniformity and reliability of the hot stretching treatment of the main bolts of the motor pump, thereby improving the overall installation quality of the motor pump.

[0062] In some of the solutions described above in this application, a movable arc-shaped seat is proposed for installing a heating lifting mechanism and controlling the lifting and lowering of the heating rod. However, in its implementation, since the main bolts are distributed in a ring array on the outer periphery of the motor pump, the movable arc-shaped seat may not be able to effectively cover all positions, resulting in blind spots or low efficiency when performing thermal stretching on the main bolts of the complete circumference.

[0063] In response, this application further proposes that the movable arc-shaped seat 8 includes a limiting slide 81 slidably disposed at the limiting guide rail 79. Both ends of the limiting slide 81 are provided with limiting end plates 83 for sliding limitation. The upper end of the limiting slide 81 is fixedly provided with an arc-shaped top plate 82 for installing the heating lifting mechanism 9. The outer periphery of the arc-shaped top plate 82 is fixedly provided with several driving external teeth 84 that mesh with gear 78. When it is necessary to heat-stretch the main bolts of the motor pump, since the main bolts are distributed in a circular array on the outer periphery of the motor pump, the movable arc-shaped seat 8 moves to achieve heat-stretching of the main bolts at different positions around the circumference. First, the movable arc-shaped seat 8 and the fixed arc-shaped seat 6 are in a vertically overlapping position. At this time, multiple main bolts at the semi-circular position near the fixed arc-shaped seat 6 of the motor pump are heat-stretched. The bolts are subjected to thermal stretching. Then, the rotary drive 7 moves to the left side of the fixed arc seat 6 to the left end. The rotary drive 7 then drives the movable arc seat 8 to continue moving to the left side of the fixed arc seat 6, so that the movable arc seat 8 extends beyond the left side of the fixed arc seat 6. This achieves thermal stretching of multiple main bolts at the left quarter circle position on the side of the motor pump away from the fixed arc seat 6. Then, the rotary drive 7 moves to the right side of the fixed arc seat 6 to the right end. The rotary drive 7 then drives the movable arc seat 8 to continue moving to the right side of the fixed arc seat 6, so that the movable arc seat 8 extends beyond the right side of the fixed arc seat 6. This achieves thermal stretching of multiple main bolts at the right quarter circle position on the side of the motor pump away from the fixed arc seat 6. Thus, thermal stretching of several main bolts around the complete circumference of the motor pump is achieved.

[0064] Specifically, the limiting slide 81 is the core load-bearing component of the movable arc-shaped seat 8, and its main function is to provide a stable moving platform for the arc-shaped top plate 82 and the heating lifting mechanism 9 installed on it. By sliding along the limiting guide rail 79, the limiting slide 81 can move precisely in a straight line or arc along a preset path, ensuring that the heating lifting mechanism 9 can accurately align with different positions of the motor pump main bolt. This can be achieved, but is not limited to: using linear rolling guide pairs, such as ball bearings or rollers, to reduce frictional resistance and improve motion accuracy and load-bearing capacity; or using a structure of sliding bearings and guide rods, achieving movement through sliding friction, suitable for applications with relatively low precision requirements but compact structures.

[0065] Limiting end plates 83 are located at both ends of the limiting slide 81. Their function is to provide physical boundaries for the sliding of the limiting slide 81, preventing it from exceeding the preset range during movement, thereby ensuring the accuracy and safety of the movement. This helps to avoid interference between the equipment and the motor pump or other components, and ensures that the movable arc seat 8 can stop accurately when thermally stretched at a specific position. The limiting end plates 83 can be implemented in ways including but not limited to: using mechanical blocks fixed to the end of the guide rail, which stop the movement when the limiting slide 81 touches the block; or combining them with limit switches or proximity sensors, which trigger a signal when the limiting slide 81 moves to a preset position, controlling the drive mechanism to stop.

[0066] The arc-shaped top plate 82 is the upper structure of the movable arc-shaped seat 8. Its arc shape is designed to better fit the outer contour of the motor pump, allowing the heating lifting mechanism 9 mounted on it to be more stable and closely positioned near the main bolt. The arc-shaped top plate 82 serves as the mounting base for the heating lifting mechanism 9, providing it with stable support and ensuring sufficient rigidity and stability during the lifting and lowering of the heating rod 500. Its installation methods can include, but are not limited to: fixing the heating lifting mechanism 9 to the arc-shaped top plate 82 with bolts for a secure connection; or using quick-installation structures such as dovetail grooves or T-slots to facilitate rapid replacement or adjustment of the heating lifting mechanism 9.

[0067] The external drive gear 84 is fixedly mounted on the outer periphery of the arc-shaped top plate 82. Its main function is to mesh with gear 78 to convert the rotational motion of motor 77 (via gear 78) into the sliding motion of the movable arc-shaped seat 8. This meshing connection ensures that the movement of the movable arc-shaped seat 8 on the limiting guide rail 79 is controlled and precise, enabling the heating lifting mechanism 9 to be positioned precisely at the main bolt as needed. The implementation of the external drive gear 84 can include, but is not limited to: using standard gear tooth profiles, such as involute tooth profiles, to ensure smooth transmission and high efficiency; or using specially designed tooth profiles to adapt to the curvature of the arc-shaped top plate 82 and optimize the meshing effect with gear 78.

[0068] Through the above technical solution, this application provides a method to effectively solve the problems of blind spots and low efficiency caused by the annular array distribution of main bolts in a motor pump during thermal stretching. Specifically, by designing the movable arc-shaped seat 8 as a sliding structure with a limiting function, and combining it with a step-by-step movement strategy, the heating lifting mechanism 9 can accurately and stably cover all the main bolts on the complete circumference of the motor pump. First, the movable arc-shaped seat 8 overlaps with the fixed arc-shaped seat 6, processing the semi-circular main bolts on the side closest to the fixed arc-shaped seat 6; then, the rotary drive 7 drives the movable arc-shaped seat 8 to extend to the left, covering the left quarter-circle area away from the fixed arc-shaped seat 6; next, it extends to the right, covering the right quarter-circle area. This segmented, step-by-step movement and positioning method not only eliminates the blind spots that may exist in traditional manual operation, ensuring that each main bolt receives uniform and sufficient thermal stretching, but also significantly improves the efficiency and accuracy of the thermal stretching operation, thereby ensuring the tightness and uniformity of the motor pump installation and improving the overall installation quality.

[0069] In some embodiments described above in this application, a heating lifting mechanism is proposed to control the heating rod to be raised and lowered and inserted into the main bolt for thermal stretching. However, in its implementation, it is necessary to drive the heating rod to move up and down more precisely and ensure that it is in close contact with the outer periphery of the motor pump in order to avoid insertion deviation and low efficiency, thereby improving the accuracy and operational reliability of thermal stretching.

[0070] In this regard, this application further proposes a heating lifting mechanism 9 including a fixed upright plate 91 fixedly installed on the upper end of the arc-shaped top plate 82, an electric telescopic cylinder 92 fixedly installed on the fixed upright plate 91, a connecting plate 93 fixedly connected to the output end of the electric telescopic cylinder 92, a connecting top plate 94 fixedly connected to the upper end of the connecting plate 93, a through hole for the heating rod 500 to pass through on the connecting top plate 94, a top pressure side plate 95 fixedly installed at the end of the connecting top plate 94 away from the connecting plate 93, a pump body arc-shaped groove 951 that fits against the outer periphery of the motor pump on the top pressure side plate 95, and a lifting component for driving the heating rod 500 to move up and down on the side of the pump body arc-shaped groove 951 near the connecting plate 93.

[0071] A lifting assembly for driving the heating rod 500 to rise and fall is provided on the side of the arc-shaped groove 951 of the pump body near the connecting plate 93. This lifting assembly is responsible for precise lifting and lowering control of the heating rod 500. The lifting assembly can adopt a miniature lead screw and nut mechanism, which drives the lead screw to rotate through a small stepper motor or servo motor to achieve precise lifting and lowering of the heating rod 500, with high precision and controllability; or it can adopt a gear and rack mechanism with a small DC motor, in which the rotation of the gear drives the linear motion of the rack to achieve lifting and lowering of the heating rod 500, which is suitable for applications requiring a certain speed and thrust.

[0072] Through the above technical solution, the heating lifting mechanism 9 provides a stable installation foundation through the fixed upright plate 91, ensuring that the entire mechanism does not shift during operation. The connecting plate 93 and the connecting top plate 94 realize the direct transmission of power and guide the heating rod 500 to accurate alignment. The pump body arc groove 951 on the top pressure side plate 95 fits tightly with the outer periphery of the motor pump, ensuring stable contact with the pump body during the thermal stretching process, preventing slippage or misalignment, and thus avoiding insertion deviation. On this basis, the lifting assembly further refines the control of the insertion depth and angle of the heating rod 500, achieving precise lifting and lowering movement. Overall, the heating lifting mechanism 9, through a multi-level, coordinated drive and positioning mechanism, significantly improves the accuracy and stability of the heating rod 500 insertion into the main bolt, effectively solving the problems of low efficiency and insertion deviation in traditional manual operation, thereby improving the overall efficiency and operational reliability of the thermal stretching treatment of the reactor coolant shielded motor pump main bolt.

[0073] In some of the solutions described above in this application, a lifting assembly is proposed to drive the heating rod to rise and fall and insert into the main bolt for thermal stretching. However, in this process, due to the lack of precise control of the driving mechanism or insufficient structural stability, the insertion position of the heating rod may be deviated, affecting the uniformity and efficiency of the thermal stretching of the main bolt, and thus failing to ensure the tightness and consistency of the motor pump installation.

[0074] In this regard, this application further proposes a lifting assembly including a lifting base plate 96 fixedly disposed at the lower part of the top pressure side plate 95, a lifting screw 97 rotatably disposed between the lifting base plate 96 and the connecting top plate 94, a lifting motor 98 for driving the lifting screw 97 to rotate fixedly disposed at the lower end of the lifting base plate 96, a screw slide 99 threadedly connected to the lifting screw 97, one end of the screw slide 99 slidably fitting against the side wall of the top pressure side plate 95, and a heating rod 500 fixedly disposed on the screw slide 99.

[0075] Through the above technical solution, the structure of the lifting assembly is optimized, providing a precise and stable driving mechanism. Specifically, the lifting base plate 96 provides a stable support foundation for the entire assembly, effectively preventing shaking during operation and ensuring system stability. The cooperation between the lifting screw 97 and the lifting motor 98 precisely converts the rotational motion of the motor into the linear lifting motion of the screw slide 99, achieving precise control of the lifting displacement of the heating rod 500. One end of the screw slide 99 slides against the side wall of the top pressure side plate 95, further limiting the lateral offset of the slide and ensuring the straightness and stability of the heating rod 500 during lifting. The heating rod 500 is directly fixed on the screw slide 99, so that the insertion position of the heating rod 500 is precisely controlled by the mechanical structure, eliminating the uncertainty and deviation that may be caused by manual operation. In view of this, this application can effectively solve the problem of heating rod insertion position deviation, ensuring that the heating rod 500 can be accurately and stably inserted into the heating hole of the main bolt, thereby improving the uniformity and efficiency of the main bolt's thermal stretching. This is crucial for ensuring the tightness and consistency of the motor pump installation, avoiding problems such as poor thermal stretching effect due to inaccurate insertion of heating rods, which in turn affects the overall performance and operational reliability of the equipment.

[0076] The following example will provide a more detailed explanation of the above technical solution: At a nuclear power plant equipment installation site, the main bolts of a reactor coolant shielded motor pump needed to be thermally stretched to ensure a tight connection between the pump body and the pump casing and to guarantee installation quality. Traditional bolt thermal stretching methods are inefficient and difficult to guarantee consistency. Therefore, the operators introduced this equipment for the task.

[0077] First, the operator pushes or pulls the equipment near the motor pump using the movable base 1. A push-pull handle 2 is fixedly installed on one side of the movable base 1, allowing the operator to easily move the equipment to the designated location. This method of movement avoids the problems of traditional equipment being bulky and difficult to position.

[0078] After the equipment arrives at the motor pump, the operator activates the vehicle lifting mechanism 3. The vehicle lifting mechanism 3 is located on top of the mobile seat 1, driving the lifting platform 4 to move up and down. The lifting platform 4 serves as the main support for the installation of the tensioning equipment; its movement causes the tensioning mechanism above it to rise and fall as a whole, ensuring that the tensioning mechanism can be precisely aligned with the height of the motor pump's main bolt.

[0079] After vertical alignment is completed, the operator activates the translation drive 5, causing the tensioning mechanism to move horizontally closer to the motor pump body. When the translation motor 52 operates, the translation lead screw 53 rotates, driving the translation slide 55 and its tensioning mechanism to move horizontally, precisely approaching the motor pump body. It is worth noting that the translation slide 55 has an elliptical plate structure, with its horizontal plate extending beyond the end of the lifting platform 4. This completely separates the tensioning mechanism from the lifting platform 4, effectively avoiding potential interference between the lifting platform 4 and the protruding parts on the outer periphery of the motor pump during the hot tensioning of the main bolts, thus improving operational flexibility and safety.

[0080] After the stretching mechanism approaches the motor pump body, it needs to perform heat stretching on each of the main bolts arranged in a ring array. The core of the stretching mechanism lies in its ability to achieve complete coverage of the main bolts in the ring array. During the heat stretching of the main bolts of the motor pump, firstly, the movable arc-shaped seat 8 and the fixed arc-shaped seat 6 are in a vertically overlapping position. At this time, multiple main bolts in the semi-circular position on the side of the motor pump closest to the fixed arc-shaped seat 6 are heat stretched. Then, motor one 75 drives the rotary drive 7 to move towards the left side of the fixed arc-shaped seat 6 to the left end. Next, motor two 77 drives gear two 78 to mesh with the drive external gear 84, causing the movable arc-shaped seat 8 to continue moving towards the left side of the fixed arc-shaped seat 6, so that the movable arc-shaped seat 8 extends beyond the left side of the fixed arc-shaped seat 6, achieving heat stretching on multiple main bolts in the left quarter-circle position on the side of the motor pump away from the fixed arc-shaped seat 6. Then, motor one 75 drives the rotary drive 7 to move towards the right side of the fixed arc-shaped seat 6 to the right end. Finally, motor 277 drives gear 278 to mesh with external drive gear 84, causing the movable arc-shaped seat 8 to continue moving towards the right side of the fixed arc-shaped seat 6. This causes the movable arc-shaped seat 8 to extend beyond the right side of the fixed arc-shaped seat 6, achieving thermal stretching of multiple main bolts located at the right quarter-circle position on the side of the motor pump away from the fixed arc-shaped seat 6. Through this step-by-step movement and extension method, this equipment can achieve thermal stretching of several main bolts around the complete circumference of the motor pump, solving the problems of low efficiency and inability to guarantee uniform stretching of the annular array bolts in traditional manual connection methods.

[0081] The specific operation of each heating and lifting mechanism 9 is as follows: When the main bolt needs to be heated, the electric telescopic cylinder 92 extends, driving the connecting top plate 94 and the top pressure side plate 95 to move towards the motor pump, so that the pump body arc groove 951 fits tightly with the outer periphery of the motor pump, providing stable support.

[0082] When the lifting screw 97 rotates, it drives the lifting motor 98 to rotate, causing the screw slide 99 and its heating rod 500 to move precisely up and down, inserting the heating rod 500 into the heating hole of the main bolt for thermal stretching. After heating is complete, the lifting screw 97 rotates in the opposite direction, pulling the heating rod 500 out of the main bolt. Subsequently, the electric telescopic cylinder 92 retracts, moving the entire heating lifting mechanism 9 away from the motor pump, preparing for the thermal stretching of the next main bolt. This automated and precise heating rod insertion and removal process significantly improves the efficiency and quality of thermal stretching operations, avoiding the uncertainty and inefficiency of traditional manual operation.

[0083] Through the aforementioned series of automated and precise mechanical movements, this equipment can efficiently and stably perform thermal stretching on the main bolts of the reactor coolant shielded motor pump annular array, greatly improving installation efficiency and quality, and solving the problems of low efficiency and compromised installation quality caused by manual operation in existing technologies.

[0084] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A device for hot-stretching the main bolts of a reactor coolant shielded motor pump, characterized in that, include: The moving seat (1) is moved to the motor pump and its main bolts are thermally stretched. The lifting platform (4) is set on the mobile seat (1) and serves as the main support for the installation of the stretching equipment; A tensioning mechanism, used for thermal stretching of the main bolts of the motor pump; Translation drive (5), which is set at the upper end of the lifting platform (4), is used to drive the stretching mechanism to move horizontally closer to the motor pump body; The stretching mechanism includes a fixed arc-shaped seat (6) fixedly mounted on a translation drive (5), a rotary drive (7) slidably mounted on the fixed arc-shaped seat (6), a movable arc-shaped seat (8) slidably connected to the rotary drive (7), and a plurality of heating lifting mechanisms (9) for controlling the heating rod (500) to rise and fall into the main bolt for thermal stretching are installed on the movable arc-shaped seat (8).

2. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 1, characterized in that, A push-pull handle (2) for pushing the device is fixedly installed on one side of the mobile seat (1). A vehicle body lifting mechanism (3) for driving the lifting platform (4) to move up and down is provided at the upper end of the mobile seat (1). The lifting platform (4) moves up and down, driving the stretching mechanism to move up and down and approach the main bolt for hot stretching.

3. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 1, characterized in that, The translation drive (5) includes two sets of platform plates (51) fixedly installed on the upper end of the lifting platform (4). A translation screw (53) is rotatably installed between the two sets of platform plates (51) and a translation guide rod (54) is fixedly installed. A translation motor (52) for driving the translation screw (53) to rotate is fixedly installed on one set of platform plates (51). A translation slide (55) is threadedly connected to the translation screw (53) and the translation slide (55) is slidably connected to the translation guide rod (54). The tensioning mechanism is fixedly installed on the translation slide (55).

4. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 3, characterized in that, The translation slide (55) has a spherical plate structure. Its vertical end is threaded through and installed on the translation screw (53) and slidably connected with the translation guide rod (54). Its horizontal plate can extend out of the end of the lifting platform (4), so that the tensioning mechanism is completely separated from the lifting platform (4), avoiding interference between the lifting platform (4) and the outer peripheral protrusion of the motor pump during the hot stretching treatment of the main bolt.

5. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 1, characterized in that, The fixed arc-shaped seat (6) includes an arc-shaped guide plate (61) fixedly mounted on the translation slide (55). The upper outer periphery of the arc-shaped guide plate (61) is provided with guide teeth (62), and the upper inner periphery of the arc-shaped guide plate (61) is fixedly provided with a limiting inner guide plate (63). The rotation drive (7) is slidably connected to the guide teeth (62).

6. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 5, characterized in that, The rotary drive (7) includes a drive main board (71) slidably disposed on the upper end of the arc-shaped guide plate (61). A guide plate sleeve (72) is provided on one side of the drive main board (71) and slides with the inner guide plate (63). A bracket (73) is fixedly disposed on the lower end of the other side of the drive main board (71). A motor (75) is fixedly disposed on the lower end of the bracket (73). A gear (76) meshing with the guide external gear (62) is fixedly installed on the output shaft of the motor (75). A limit guide rail (79) is fixedly disposed on the upper end of the drive main board (71). A movable arc-shaped seat (8) is slidably disposed at the limit guide rail (79).

7. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 6, characterized in that, The drive motherboard (71) is fixedly provided with a bracket two (74) on the upper end of the side near the bracket one (73). A vertically downward motor two (77) is fixedly installed on the upper end of the bracket two (74). A gear two (78) for driving the movable arc seat (8) to slide along the limiting guide rail (79) is fixedly connected to the output end of the motor two (77).

8. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 7, characterized in that, The movable arc-shaped seat (8) includes a limiting slide (81) slidably disposed on the limiting guide rail (79). Both ends of the limiting slide (81) are provided with limiting end plates (83) for sliding limiting. The upper end of the limiting slide (81) is fixedly provided with an arc-shaped top plate (82) for installing the heating lifting mechanism (9). The outer periphery of the arc-shaped top plate (82) is fixedly provided with a plurality of driving external teeth (84) that mesh with the gear two (78). When it is necessary to heat stretch the main bolts of the motor pump, since the main bolts are distributed in a ring array on the outer periphery of the motor pump, the hot stretching of the main bolts at different positions around the ring is achieved by moving the movable arc seat (8). First, the movable arc seat (8) and the fixed arc seat (6) are in the vertical overlapping position. At this time, multiple main bolts at the semi-circular position on the side of the motor pump close to the fixed arc seat (6) are heat stretched. Then, the rotary drive (7) moves towards the left side of the fixed arc seat (6) to the left end. Then, the rotary drive (7) drives the movable arc seat (8) to continue moving towards the left side of the fixed arc seat (6), so that the movable arc seat... (8) Extend the left side of the fixed arc seat (6) to achieve thermal stretching of multiple main bolts at the left quarter circle position on the side of the motor pump away from the fixed arc seat (6). Then, rotate the drive (7) towards the right side of the fixed arc seat (6) to the right end. Then, drive the movable arc seat (8) to continue moving towards the right side of the fixed arc seat (6) through the rotation drive (7), so that the movable arc seat (8) extends out of the right side of the fixed arc seat (6) to achieve thermal stretching of multiple main bolts at the right quarter circle position on the side of the motor pump away from the fixed arc seat (6), thereby achieving thermal stretching of several main bolts on the complete circumference of the motor pump.

9. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 8, characterized in that, The heating lifting mechanism (9) includes a fixed upright plate (91) fixedly installed on the upper end of the arc-shaped top plate (82). An electric telescopic cylinder (92) is fixedly installed on the fixed upright plate (91). A connecting plate (93) is fixedly connected to the output end of the electric telescopic cylinder (92). A connecting top plate (94) is fixedly connected to the upper end of the connecting plate (93). A through hole for the heating rod (500) to pass through is provided on the connecting top plate (94). A top pressure side plate (95) is fixedly provided at the end of the connecting top plate (94) away from the connecting plate (93). A pump body arc groove (951) that fits against the outer periphery of the motor pump is provided on the top pressure side plate (951). A lifting component for driving the heating rod (500) to move up and down is provided on the side of the pump body arc groove (951) near the connecting plate (93).

10. The reactor coolant shielded motor pump main bolt hot stretching device according to claim 9, characterized in that, The lifting assembly includes a lifting base plate (96) fixedly disposed at the lower part of the top pressure side plate (95). A lifting screw (97) is rotatably disposed between the lifting base plate (96) and the connecting top plate (94). A lifting motor (98) for driving the lifting screw (97) to rotate is fixedly disposed at the lower end of the lifting base plate (96). A screw slide (99) is threaded through the lifting screw (97). One end of the screw slide (99) slides against the side wall of the top pressure side plate (95). The heating rod (500) is fixedly disposed on the screw slide (99).

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