Bending device for production of steel structural member in nuclear reactor and residual stress inhibition process of bending device

Abstract

The invention relates to the technical field of production of steel structural parts in nuclear reactors, in particular to a bending device for production of steel structural parts in nuclear reactors and a residual stress suppression process of the bending device. The bending device comprises a workbench, a hydraulic jacking mechanism, a second bending mold, a second bending head and an auxiliary positioning mechanism; a plurality of penetrating holes are formed in the bottom of an inner cavity of the mounting groove in a penetrating mode, a bottom support is fixedly installed at the bottom of the workbench, and two sliding supporting mechanisms are fixedly installed at the top of the workbench. According to the bending device, the bending speed and the bending position can be changed by replacing multiple dies and supporting the dies through the hydraulic cylinders of multiple cylinders and a single cylinder to stretch out and draw back to be matched with bending, pre-bending heating is combined, generation of internal stress can be reduced to a certain degree, the bending operation machining requirements of different steel structural parts are met, and the bending machining efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of the production of steel structure components in a nuclear reactor, and particularly relates to a bending device for the production of steel structure components in a nuclear reactor and a residual stress suppression process thereof. Background Art

[0002] A nuclear reactor, also known as an atomic energy reactor or a reactor, is a device that can maintain a controllable self-sustaining chain nuclear fission reaction to realize the utilization of nuclear energy. By reasonably arranging nuclear fuel in the nuclear reactor, a self-sustaining chain nuclear fission process can occur therein without adding a neutron source. Strictly speaking, the term "reactor" should cover fission reactors, fusion reactors, and fission-fusion hybrid reactors, but generally only refers to fission reactors. Steel structure components are formed by connecting multiple parts together through various methods such as welding, riveting, or bolt connection. These parts are interconnected and restricted from each other, forming an organic whole.

[0003] During the structural installation and use process in a nuclear reactor, since the steel structure components need to be used in a special environment and ensure that the steel used meets the standards of steel for nuclear reactors, having the required high strength, high toughness, corrosion resistance, low activation, etc. characteristics to extend the service life. However, during the bending process, traditional bending devices and bending processes usually generate a certain amount of internal stress, which is not conducive to long-term use in a nuclear reactor. Moreover, for traditional bending devices, the bending dies are usually relatively single, and it is rather troublesome to replace them. Also, they cannot adapt to various bendings and the function of selecting die installation according to the bending size, thus requiring the production of multiple dies, unable to reduce the number of dies, resulting in an increase in capital use, and unable to control the bending process according to actual needs, thereby reducing the yield rate. Based on this, a bending device for the production of steel structure components in a nuclear reactor and a residual stress suppression process thereof are proposed. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems in the background art, and a bending device for the production of steel structure components in a nuclear reactor and a residual stress suppression process thereof are proposed.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A bending device for the production of steel structural parts in a nuclear reactor, comprising a workbench, a hydraulic lifting mechanism, a second bending die, a second bending head and an auxiliary positioning mechanism. A plurality of installation grooves are formed in the top of the workbench, and a plurality of through holes are formed in the bottom of the inner cavity of the installation groove in a penetrating manner. A bottom bracket is fixedly installed at the bottom of the workbench, and two sliding support mechanisms are fixedly installed at the top of the workbench. A bending mechanism is movably installed inside the two sliding support mechanisms, and a first bending head is installed at the output end of the bending mechanism. A first bending die is movably installed inside the installation groove, a reinforcement mechanism is fixedly installed at the bottom of the workbench, and a control console is fixedly installed at the top of the workbench.

[0007] The hydraulic lifting mechanism includes a second mounting plate. A third hydraulic telescopic rod is fixedly installed on one side of the second mounting plate. The output end of the third hydraulic telescopic rod is fixedly installed with a sealing piston. A connecting cylinder is movably sleeved outside the sealing piston. The output end of the connecting cylinder is communicated with a synchronous isobaric hydraulic pipe. An electric control valve is movably installed inside the synchronous isobaric hydraulic pipe. The end of the synchronous isobaric hydraulic pipe away from the connecting cylinder is communicated with a second hydraulic telescopic rod. A threaded groove is formed in the top of the output end of the second hydraulic telescopic rod. A first mounting plate is fixedly installed at the bottom of the second hydraulic telescopic rod. The hydraulic lifting mechanism is linearly and evenly distributed inside the reinforcement mechanism.

[0008] Preferably, the installation grooves are linearly and evenly distributed on the top of the workbench, and the through holes are linearly and evenly distributed inside the installation grooves. Both of the two sliding support mechanisms include sliding rails and reinforcing ribs. The reinforcing ribs are linearly and symmetrically fixedly installed on both sides of the sliding rails, and the sliding rails are fixedly installed on the top of the workbench.

[0009] Preferably, the reinforcement mechanism includes an installation box, which is fixedly installed at the bottom of the workbench. A plurality of reinforcement frames are fixedly installed at the bottom of the installation box, and the reinforcement frames are linearly and evenly distributed at the bottom of the installation box. The specification size of the output end of the second hydraulic telescopic rod is adapted to the specification size of the through hole. The hydraulic lifting mechanism is located inside the installation box. The output end of the second hydraulic telescopic rod movably penetrates through the installation box and extends into the installation groove. The third hydraulic telescopic rod and the first mounting plate are both fixedly installed inside the installation box through bolts and brackets. The distance between the output end of the synchronous isobaric hydraulic pipe and the second hydraulic telescopic rod is equal to the distance of the output end of the connecting cylinder at each place, and the second hydraulic telescopic rod and the synchronous isobaric hydraulic pipe are linearly and equidistantly and evenly distributed. Hydraulic oil is provided inside the connecting cylinder, the synchronous isobaric hydraulic pipe and the second hydraulic telescopic rod. There are two specifications for the second hydraulic telescopic rod. One is the hydraulic rod in a multi-cylinder synchronous hydraulic system, and the other is the hydraulic rod with single-cylinder high-precision control.

[0010] Preferably, the bending mechanism includes a gantry. At the bottom of both ends of the gantry, sliding seats are fixedly installed. Inside the sliding seats, sliding columns are movably sleeved. On one side of the sliding seats, a first hydraulic telescopic rod is fixedly installed. The sliding seats are slidably installed inside the sliding rails. The end of the first hydraulic telescopic rod away from the sliding seats is fixedly installed inside the sliding rails. Both ends of the sliding columns are fixedly installed inside the sliding rails. At the bottom surface of the top of the gantry, an electronically controlled high-precision hydraulic cylinder telescopic mechanism is fixedly installed. The output end of the electronically controlled high-precision hydraulic cylinder telescopic mechanism is fixedly installed with a connecting frame. At the bottom of the connecting frame, a first mounting seat is fixedly installed. Inside the inner sides of both ends of the first mounting seat, sliding rods are movably sleeved. The top of the sliding rods is fixedly installed at the bottom surface of the top of the gantry. The bottom end of the sliding rods is fixedly installed with a reinforcement seat, and the reinforcement seat is fixedly installed inside the gantry.

[0011] Preferably, the first bending head includes a bending die head. At the top of the bending die head, a number of first spring limit telescopic mechanisms are fixedly installed. The first spring limit telescopic mechanisms are linearly and evenly distributed at the top of the bending die head. Inside the top end of the first spring limit telescopic mechanism, a hexagon socket head cap screw is threadedly connected. The hexagon socket head cap screw movably penetrates through the first mounting seat and extends into the first spring limit telescopic mechanism. Inside the first mounting seat, a bolt hole adapted to the hexagon socket head cap screw is opened. The specification size of the hexagon socket head cap screw is adapted to the specification size of the thread groove. One end of the bending die head is an arc surface, and the other end is a right-angle surface.

[0012] Preferably, the first bending die includes a limit base. On the opposite sides of both ends of the limit base, rotating seats are movably installed through bearings. On the opposite sides of the rotating seats, bending die seats are fixedly installed. Inside the rotating seats, infrared thermopile sensors are embedded. Inside the bending die seats, a number of arc-shaped electromagnetic induction heating coil discs are installed. On the outside of the bending die seats, bending grooves are opened. The specification size of the bending die seats is adapted to the specification size of the bending die head. Through the bottom of the limit base, a number of hexagon socket head cap screws are movably penetrated. The specification size of the hexagon socket head cap screws is adapted to the specification size of the thread groove. The specification size of the limit base is adapted to the specification size of the installation groove. The notch of the bending die seat and the workbench are on the same horizontal plane. Inside the limit base, bolt holes adapted to the hexagon socket head cap screws are opened. The hexagon socket head cap screws are linearly and evenly distributed inside the limit base. The arc-shaped electromagnetic induction heating coil discs are in a curved arc shape inside the bending die seats. The arc-shaped electromagnetic induction heating coil discs are linearly and evenly distributed inside the bending die seats. The outer surface of the bending die seat is arc-shaped, and the angular range of the arc includes 90°, 120°, and 135°.

[0013] Preferably, the second bending die includes a first base. Inner hexagonal bolts III are movably inserted into the inner sides of both ends of the first base. The specification dimensions of the inner hexagonal bolts III are adapted to those of the threaded grooves. Bolt holes adapted to the inner hexagonal bolts III are provided in the interiors of both ends of the first base. A number of first adjustment holes are provided in the interiors of both sides of the top end of the first base. Steel bar limiting rollers are movably inserted into the interiors of the opposite sides of the first adjustment holes. Both ends of the steel bar limiting rollers are fixed to the opposite sides of the first base by bolts. The steel bar limiting rollers are composed of support shafts and bending rollers movably supported by bearings. A chute is provided in the middle of the top end of the first base. A slide bar is slidably mounted in the interior of the chute. Second spring limiting and telescoping mechanisms are fixedly mounted at the bottoms of both ends of the slide bar. The bottoms of the second spring limiting and telescoping mechanisms are fixedly mounted at the bottom of the inner cavity of the first base. A steel bar bending roller sleeve is movably sleeved on the outer side of the slide bar through a bearing. The second bending head includes a second base. Inner hexagonal bolts IV are movably inserted into the interiors of both ends of the second base. Bolt holes adapted to the inner hexagonal bolts IV are provided in the interiors of both ends of the second base. The specification dimensions of the inner hexagonal bolts IV are adapted to those of the threaded grooves. A number of second adjustment holes are provided in the interiors of both sides of the top end of the second base. The second adjustment holes are linearly and evenly distributed in the interiors of both ends of the second base. A third bending head is movably mounted inside the second base. The third bending head is fixed to the inside of the second base by bolts passing through the second adjustment holes. The specification dimensions of the second base and the first base are adapted to those of the installation groove. The specification dimensions of the third bending head are adapted to those of the first base.

[0014] Preferably, the auxiliary positioning mechanism includes an L-shaped plate. A third base is fixedly mounted at the bottom of the L-shaped plate. A number of clamping bolts are threadedly connected inside the L-shaped plate. A bearing support is sleeved on the outer side of the bottom end of the clamping bolt. A first connecting plate is fixedly mounted at the bottom of the bearing support. A number of third spring limiting and telescoping mechanisms are fixedly mounted at the bottom of the first connecting plate. The third spring limiting and telescoping mechanisms are linearly and evenly distributed at the bottom of the first connecting plate. A limiting clamping plate is fixedly mounted at the bottom of the third spring limiting and telescoping mechanisms. The specification dimensions of the third base are adapted to those of the installation groove. A number of inner hexagonal bolts V are movably inserted into the interior of the third base. The specification dimensions of the inner hexagonal bolts V are adapted to those of the threaded grooves. Bolt holes adapted to the inner hexagonal bolts V are provided in the interior of the third base. The inner hexagonal bolts V are linearly and evenly distributed in the interior of the third base. There are two specifications of the auxiliary positioning mechanism, and the two auxiliary positioning mechanisms are axially symmetrically distributed on the top of the workbench.

[0015] In the above-mentioned process for suppressing residual stress of steel structure parts in a nuclear reactor, the above-mentioned bending device for producing steel structure parts in a nuclear reactor is applied, including the following steps:

[0016] S1. Segment and cut the steel plates, steel sections, steel bars, and steel rods that need to be bent. For example, when bending a steel plate, determine the angle of die processing according to the processing requirements of the fittings. Common bending angles are 90°, 120°, and 135°. Then install the first bending die inside the installation groove, install the first bending head at the output end of the bending mechanism, and symmetrically install two auxiliary positioning mechanisms on both sides of the first bending die and the first bending head.

[0017] S2. Then select the bending radius according to the thickness of the bent steel. For low-carbon steel, when the thickness is 1 - 2 mm, the bending radius is 1 - 1.5 times the material thickness; when the thickness is 2 - 4 mm, the bending radius is about 1.5 - 2 times the thickness; when the thickness is 4 - 6 mm, the bending radius is 2 - 3 times the thickness; when the thickness is greater than 6 mm, the bending radius is not less than 3 times the thickness. For high-strength alloy steel, to prevent the material from cracking during bending, the bending radius is larger than that of low-carbon steel. For example, for high-strength alloy steel with a thickness of 1 - 2 mm, the bending radius is 1.5 - 2 times the material thickness; as the thickness increases, the multiple relationship between the bending radius and the thickness will also increase accordingly. Then, after selecting the die and processing mode, place the steel plate in the processing position.

[0018] S3. Then, according to the thickness of the steel plate, rotate the clamping bolt to make the clamping bolt rotate with the bearing support and extend downward, and squeeze the first connecting plate, the third spring limit telescopic mechanism, and the limit clamping plate to move downward, and clamp the outside of the steel plate. Then, by controlling the hydraulic lifting mechanism corresponding to the first bending head and the first bending die to extend, the second hydraulic telescopic rod is pushed out, the first bending die is pushed out, and the bending surface of the bending die seat is flush with the plane of the workbench and the bottom of the steel plate. Then, start the electric control high-precision hydraulic cylinder telescopic mechanism to extend, and push the connecting frame and the first mounting seat to move downward, thereby promoting the first spring limit telescopic mechanism and the bending die head to move downward, so as to contact the top of the steel plate and gradually move downward to gradually bend the steel plate to the position where it fits the bending die seat.

[0019] S4. Meanwhile, the arc-shaped electromagnetic induction heating coil disc starts to heat the bent part of the steel plate electromagnetically. The temperature is measured by an infrared thermopile sensor. By controlling the power of the arc-shaped electromagnetic induction heating coil disc and combining with the measured temperature of the infrared thermopile sensor, the bending temperature of the steel structure steel plate used in the nuclear reactor is controlled. For example, for high-strength low-alloy steel, the heating temperature is controlled within the range of 600 - 900 °C. For instance, when bending Q460 steel, the heating temperature is selected around 700 - 850 °C; for higher-strength alloy steels, such as some steels containing more alloying elements like chromium and molybdenum, the heating temperature needs to reach 800 - 900 °C to ensure that the material has good plasticity for easy bending and forming. By controlling the slow extension of the electro-controlled high-precision hydraulic cylinder telescopic mechanism, the bending speed and heating speed increase linearly, avoiding the situation of too fast temperature and bending speed. The operation of the two auxiliary positioning mechanisms clamping the steel plate is suitable for bending the middle part of the steel plate into shape. If a right-angle bend is required, replace the first right-angle bending head and the first bending die, and clamp and fix one end through the auxiliary positioning mechanism.

[0020] S5. After bending, the cooling speed has a great influence on the performance of the high-strength steel structure steel used in the nuclear reactor. Usually, it is necessary to control the cooling speed appropriately to avoid excessive internal stress or abnormal microstructure transformation. In the production after bending, air cooling or slow cooling methods need to be adopted. During air cooling, the cooling speed is relatively slow, generally about 5 - 15 °C per minute; for slow cooling, the workpiece can be placed in heat-insulating materials to make it cool slowly, and the cooling speed is in the range of 1 - 5 °C per minute. By reducing the bending speed, heating at the bent part, and slow cooling, the internal stress generated in the steel structure of the nuclear reactor during the bending process is reduced to increase the service strength. And by adopting the secondary bending process, when reducing the bending speed, after a slow first-time bending, the rigid bending contact force is reduced by the first spring limit telescopic mechanism, and then gradually heated during the bending process for secondary bending, thereby reducing the bending stress to ensure the quality during the bending process and increasing the yield rate.

[0021] Compared with the existing technology, the advantages of a bending device and its residual stress suppression process for producing steel structure parts in a nuclear reactor provided by the present invention are as follows:

[0022] 1. The steel plates, steel sections, steel bars, and steel rods to be bent are segmented and cut. When bending a steel plate, the angle of the die processing is determined according to the processing requirements of the fittings. Common bending angles are 90°, 120°, and 135°. Then, the first bending die is installed inside the installation groove, the first bending head is installed at the output end of the bending mechanism, and the two auxiliary positioning mechanisms are symmetrically installed on both sides of the first bending die and the first bending head, enabling the replacement of different bending dies.

[0023] 2. Also, when replacing the die for bending, the arc-shaped electromagnetic induction heating coil disc starts. The electromagnetic heating is carried out at the bending part of the steel plate, and the temperature is measured by an infrared thermopile sensor. By controlling the power of the arc-shaped electromagnetic induction heating coil disc and combining with the measured temperature of the infrared thermopile sensor, the bending temperature of the steel structure steel plate used in the nuclear reactor is controlled. For example, for high-strength low-alloy steel, the heating temperature is controlled within the range of 600 - 900 °C. For example, when bending Q460 steel, the heating temperature is selected around 700 - 850 °C; for higher-strength alloy steel, such as some steels containing more alloying elements such as chromium and molybdenum, the heating temperature needs to reach 800 - 900 °C to ensure that the material has good plasticity and is convenient for bending and forming. By controlling the slow extension of the electro-hydraulic high-precision hydraulic cylinder telescopic mechanism, the bending speed and the heating speed increase linearly, avoiding the situation of too fast temperature and bending speed. The operation of the two auxiliary positioning mechanisms clamping the steel plate is suitable for bending the steel plate into a middle shape;

[0024] 3. By reducing the bending speed, heating at the bending part, and slowly reducing the temperature, the internal stress generated during the bending process for the steel structure in the nuclear reactor is reduced to increase the service strength. And by adopting the secondary bending process, when reducing the bending speed, after a slow first-time bending, the rigid bending contact force is reduced by the spring limit telescopic mechanism I, and gradually heated during the bending process for secondary bending, thereby reducing the bending stress to ensure the quality during the bending process and increasing the yield rate;

[0025] In summary, by using the replacement of multiple dies and the telescopic cooperation of the hydraulic cylinders of multiple cylinders and single cylinders to support the die for bending, the bending speed and position can be changed. Combined with pre-bending heating, the generation of internal stress can be reduced to a certain extent, ensuring the bending operation processing requirements of different steel structure parts and increasing the bending processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the front view three-dimensional external structure schematic diagram of the present invention;

[0027] Figure 2 is the rear view upward three-dimensional external structure schematic diagram of the present invention;

[0028] Figure 3 is the front view sectional structure schematic diagram of the present invention;

[0029] Figure 4 is the right view sectional structure schematic diagram of the present invention;

[0030] Figure 5 is the three-dimensional external structure schematic diagram of the hydraulic lifting mechanism of the present invention;

[0031] Figure 6 It is a schematic front view sectional view of the hydraulic jacking mechanism of the present invention;

[0032] Figure 7 It is the present invention Figure 1 An enlarged schematic view of the structure at position A in;

[0033] Figure 8 It is the present invention Figure 1 An enlarged schematic view of the structure at position B in;

[0034] Figure 9 It is the present invention Figure 3 An enlarged schematic view of the structure at position C in;

[0035] Figure 10 It is the present invention Figure 3 An enlarged schematic view of the structure at position D in;

[0036] Figure 11 It is the present invention Figure 4 An enlarged schematic view of the structure at position E in;

[0037] Figure 12 It is a schematic view of the external shape of the arc-shaped electromagnetic induction heating coil disc of the present invention.

[0038] In the figure: 1, workbench; 101, mounting groove; 102, bottom support; 103, through hole; 2, sliding support mechanism; 201, sliding rail; 202, reinforcing rib; 3, reinforcing mechanism; 301, mounting box; 302, reinforcing frame; 4, control console; 5, bending mechanism; 501, gantry; 502, electro-controlled high-precision hydraulic cylinder telescopic mechanism; 503, sliding rod; 504, reinforcing seat; 505, sliding seat; 506, first hydraulic telescopic rod; 507, sliding column; 508, connecting frame; 509, first mounting seat; 6, hydraulic lifting mechanism; 601, second hydraulic telescopic rod; 602, first mounting plate; 603, threaded groove; 604, synchronous isobaric hydraulic pipe; 605, electro-controlled valve; 606, connecting cylinder; 607, third hydraulic telescopic rod; 608, second mounting plate; 609, sealing piston; 7, first bending head; 701, bending die head; 702, first hexagon socket head bolt; 703, first spring limit telescopic mechanism; 8, first bending die; 801, limit base; 802, rotating seat; 803, bending die seat; 804, second hexagon socket head bolt; 805, arc electromagnetic induction heating coil disc; 806, infrared thermopile sensor; 9, second bending die; 901, first base; 902, third hexagon socket head bolt; 903, first adjustment hole; 904, chute; 905, slide bar; 906, steel bar bending roller sleeve; 907, steel bar limit roller; 908, second spring limit telescopic mechanism; 10, second bending head; 1001, second base; 1002, fourth hexagon socket head bolt; 1003, second adjustment hole; 1004, third bending head; 11, auxiliary positioning mechanism; 1101, L-shaped plate; 1102, clamping bolt; 1103, bearing support; 1104, first connecting plate; 1105, third spring limit telescopic mechanism; 1106, limit clamping plate; 1107, third base; 1108, fifth hexagon socket head bolt. Detailed implementation manners

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0040] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0041] Refer to Figures 1 - 12A bending device for producing steel structural parts in a nuclear reactor comprises a workbench 1, a hydraulic lifting mechanism 6, a bending die 9, a bending head 10 and an auxiliary positioning mechanism 11. A plurality of mounting grooves 101 are provided on the top of the workbench 1, and a plurality of through holes 103 are provided at the bottom of the inner cavity of the mounting groove 101. A bottom bracket 102 is fixedly installed at the bottom of the workbench 1, two sliding support mechanisms 2 are fixedly installed on the top of the workbench 1, and a bending mechanism 5 is movably installed on the inner side of the two sliding support mechanisms 2, a bending head 7 is installed at the output end of the bending mechanism 5, a bending die 8 is movably installed inside the mounting groove 101, a reinforcement mechanism 3 is fixedly installed at the bottom of the workbench 1, and a control console 4 is fixedly installed on the top of the workbench 1.

[0042] The hydraulic jacking mechanism 6 includes a mounting plate 2 608, a hydraulic telescopic rod 3 607 is fixedly installed on one side of the mounting plate 2 608, a sealing piston 609 is fixedly installed on the output end of the hydraulic telescopic rod 3 607, a connecting tube 606 is movably sleeved on the outer side of the sealing piston 609, the output end of the connecting tube 606 is connected to a synchronous isobaric hydraulic pipe 604, an electric-controlled valve 605 is movably installed on the inner side of the synchronous isobaric hydraulic pipe 604, the end of the synchronous isobaric hydraulic pipe 604 away from the connecting tube 606 is connected to a hydraulic telescopic rod 2 601, a threaded groove 603 is provided on the top of the output end of the hydraulic telescopic rod 2 601, a mounting plate 1 602 is fixedly installed on the bottom of the hydraulic telescopic rod 2 601, and the hydraulic jacking mechanism 6 is linearly and evenly distributed inside the reinforcement mechanism 3.

[0043] In this implementation plan, steel plates, steel sections, steel bars, and steel rods that need to be bent are segmented and cut. For example, when bending a steel plate, the angle of die processing is determined according to the processing requirements of the fittings. Common bending angles are 90°, 120°, and 135°. Then, the first bending die 8 is installed inside the installation groove 101, the first bending head 7 is installed at the output end of the bending mechanism 5, and two auxiliary positioning mechanisms 11 are symmetrically installed on both sides of the first bending die 8 and the first bending head 7. After selecting the die and processing mode, the steel plate is placed at the processing position. Then, according to the thickness of the steel plate, the clamping bolt 1102 is rotated to make the clamping bolt 1102 extend downward with the rotation of the bearing support 1103 and its threaded connection with the L-shaped plate 1101, and it squeezes the first connecting plate 1104, the third spring limit telescopic mechanism 1105, and the limit clamping plate 1106 to move downward, and the outside of the steel plate is clamped. Then, by controlling the hydraulic lifting mechanism 6 corresponding to the first bending head 7 and the first bending die 8 to extend, the hydraulic telescopic rod 601 is pushed out to push out the first bending die 8, and the bending surface of the bending die base 803 is flush with the plane of the workbench 1 and the bottom of the steel plate. Then, the electric control high-precision hydraulic cylinder telescopic mechanism 502 is started to extend, and it pushes the connecting frame 508 and the first mounting seat 509 to move downward, thereby causing the first spring limit telescopic mechanism 703 and the bending die head 701 to move downward, so as to contact the top of the steel plate and gradually move downward to gradually bend the steel plate to the position where it fits the bending die base 803. At the same time, the arc-shaped electromagnetic induction heating coil disc 805 is started to electromagnetically heat the bent part of the steel plate, and the temperature is measured by the infrared thermopile sensor 806. By controlling the power of the arc-shaped electromagnetic induction heating coil disc 805 and combining the measured temperature of the infrared thermopile sensor 806, the bending temperature of the steel plate used for the steel structure inside the nuclear reactor is controlled to ensure that the material has good plasticity and is convenient for bending and forming. By controlling the slow extension of the electric control high-precision hydraulic cylinder telescopic mechanism 502, the bending speed and the heating speed increase linearly, avoiding the situation of too fast temperature and bending speed. The operation of the two auxiliary positioning mechanisms 11 clamping the steel plate is suitable for bending and forming the middle part of the steel plate. If a right-angle bend is required, replace the first bending head 7 and the first bending die 8 with right angles, and clamp and fix one end through the auxiliary positioning mechanism 11.

[0044] Among them, the installation grooves 101 are linearly and evenly distributed on the top of the workbench 1, and the through holes 103 are linearly and evenly distributed inside the installation grooves 101. The two sliding support mechanisms 2 both include sliding rails 201 and reinforcing ribs 202. The reinforcing ribs 202 are linearly and symmetrically fixedly installed on both sides of the sliding rails 201, and the sliding rails 201 are fixedly installed on the top of the workbench 1.

[0045] In this embodiment, the through hole 103 provides an extension space for the second hydraulic telescopic rod 601, facilitates passing through the mounting box 301 and the workbench 1, enables it to extend to the inside of the mounting groove 101, and limits and mounts the die plate through the mounting groove 101, and provides an up-and-down displacement space to control the distance between the die and the bending position, facilitating changing the bending position according to different bending dies, thereby facilitating subsequent processing. The sliding rail 201 provides a sliding limit position for the sliding seat 505, and cooperates with the reinforcing rib 202 to increase the structural force on the sliding seat 505, facilitating increasing the stress intensity and relative stability of the structure during movement.

[0046] Among them, the reinforcement mechanism 3 includes a mounting box 301, which is fixedly installed at the bottom of the workbench 1. A plurality of reinforcing frames 302 are fixedly installed at the bottom of the mounting box 301, and the reinforcing frames 302 are linearly and evenly distributed at the bottom of the mounting box 301. The specification size of the output end of the second hydraulic telescopic rod 601 is adapted to the specification size of the through hole 103. The hydraulic lifting mechanism 6 is located inside the mounting box 301. The output end of the second hydraulic telescopic rod 601 movably penetrates the mounting box 301 and extends movably into the mounting groove 101. The third hydraulic telescopic rod 607 and the first mounting plate 602 are both fixedly installed inside the mounting box 301 through bolts and brackets. The distance between the output end of the synchronous isobaric hydraulic pipe 604 and the output end of the second hydraulic telescopic rod 601 is equal at each place, and the second hydraulic telescopic rod 601 and the synchronous isobaric hydraulic pipe 604 are linearly and equidistantly and evenly distributed. Hydraulic oil is provided inside the connecting cylinder 606, the synchronous isobaric hydraulic pipe 604, and the second hydraulic telescopic rod 601. The second hydraulic telescopic rod 601 has two specifications, one is a hydraulic rod in a multi-cylinder synchronous hydraulic system, and the other is a hydraulic rod with single-cylinder high-precision control.

[0047] In this embodiment, the mounting box 301 and the reinforcing frame 302 provide support and fixation for the hydraulic lifting mechanism 6, providing a structural support function. The bottom of the reinforcing frame 302 is fixedly installed inside the bottom bracket 102 through a bracket, thereby facilitating providing the structural support strength. When the hydraulic lifting mechanism 6 operates, the third hydraulic telescopic rod 607 extends and drives the sealing piston 609 to move inside the connecting cylinder 606, thereby pushing the hydraulic oil, and guiding it through the connecting cylinder 606 and the synchronous isobaric hydraulic pipe 604 into the second hydraulic telescopic rod 601, thereby synchronously extending a plurality of second hydraulic telescopic rods 601, facilitating ejecting the die mounted on the top. This solution demonstrates a synchronous extension solution, and according to different precision requirements, the hydraulic rods in the multi-cylinder synchronous hydraulic system in the prior art are used. When a single die needs to be lifted, the hydraulic rod with single-cylinder high-precision control is used for single extension, thereby cooperating with the structure for lifting use, facilitating control to increase the use effect of the structure, and cooperating with different uses to increase the use efficiency of the structure.

[0048] Among them, the bending mechanism 5 includes a gantry 501. At the bottom of both ends of the gantry 501, sliding seats 505 are fixedly installed. A sliding column 507 is movably sleeved inside the sliding seat 505. A first hydraulic telescopic rod 506 is fixedly installed on one side of the sliding seat 505. The sliding seat 505 is slidably installed inside the sliding rail 201. The end of the first hydraulic telescopic rod 506 away from the sliding seat 505 is fixedly installed inside the sliding rail 201. Both ends of the sliding column 507 are fixedly installed inside the sliding rail 201. On the bottom surface of the top end of the gantry 501, an electronically controlled high-precision hydraulic cylinder telescopic mechanism 502 is fixedly installed. The output end of the electronically controlled high-precision hydraulic cylinder telescopic mechanism 502 is fixedly installed with a connecting frame 508. At the bottom of the connecting frame 508, a first mounting seat 509 is fixedly installed. Inside the inner sides of both ends of the first mounting seat 509, sliding rods 503 are movably sleeved. The top of the sliding rod 503 is fixedly installed on the bottom surface of the top end of the gantry 501. The bottom end of the sliding rod 503 is fixedly installed with a reinforcing seat 504. The reinforcing seat 504 is fixedly installed inside the gantry 501.

[0049] In this implementation plan, when the electronically controlled high-precision hydraulic cylinder telescopic mechanism 502 extends and pushes the connecting frame 508 and the first mounting seat 509 to move downward, it further causes the first spring limit telescopic mechanism 703 and the bending die head 701 to move downward, thereby contacting the top of the steel plate and gradually moving downward to gradually bend the steel plate to a position that fits the bending die base 803. And the lifting position of the connecting frame 508 is convenient for disassembling and assembling the hexagon socket head bolt 702 on the top of the first mounting seat 509 through a special elbow hexagon socket wrench, facilitating the disassembly and replacement of the first bending elbow 7, and facilitating the change and replacement of the mold according to different operation requirements. The sliding rod 503 and the reinforcing seat 504 provide sliding support and limit for the first mounting seat 509 to increase the stable position and ensure the structural strength.

[0050] Among them, the first bending elbow 7 includes a bending die head 701. A number of first spring limit telescopic mechanisms 703 are fixedly installed on the top of the bending die head 701. The first spring limit telescopic mechanisms 703 are linearly and evenly distributed on the top of the bending die head 701. Inside the top end of the first spring limit telescopic mechanism 703, a hexagon socket head bolt 702 is threadedly connected. The hexagon socket head bolt 702 movably penetrates through the first mounting seat 509 and extends into the inside of the first spring limit telescopic mechanism 703. A bolt hole adapted to the hexagon socket head bolt 702 is opened inside the first mounting seat 509. The specification size of the hexagon socket head bolt 702 is adapted to the specification size of the thread groove 603. One end of the bending die head 701 is an arc surface and the other end is a right-angle surface.

[0051] In this implementation scheme, the first spring limit telescopic mechanism 703 is convenient for providing stable buffering between the first mounting seat 509 and the bending die head 701, facilitating slow bending, reducing the accumulation of internal stress in rigid bending. Moreover, the first spring limit telescopic mechanism 703 and the subsequent spring limit telescopic mechanisms are all elastic telescopic components, such as spring limit mechanisms, industrial shock absorbers, and gas spring mechanisms, which have the functions of elasticity and limit telescopic components. And a bolt groove is opened at the installation position at the top of the mechanism component to connect and provide elastic limit support, ensuring the basic functions of providing elastic force and limit. The first hexagon socket head bolt 702 is used for installation and connection with the bolt hole of the first mounting seat 509, facilitating subsequent installation and use. The two end faces of the bending die head 701 are convenient for replacing different bending angle positions. And the bending die head 701, the first hexagon socket head bolt 702, and the installation groove 101 are all symmetrically arranged components, facilitating angle and direction replacement, thereby reducing the amount of molds. For example, the two of the auxiliary positioning mechanism 11 can be installed by reversing the direction, and are symmetrically arranged everywhere, facilitating structural installation. And the bolts everywhere are adapted to the thread groove 603, facilitating the replacement and installation of different molds. For example, the second bending die 9 and the second bending head 10 can be installed at the bottom of the first mounting seat 509 or at the top of the installation groove 101 and the thread groove 603 as required, facilitating multi-angle use, reducing the amount of molds, reducing the use of funds, and ensuring the simplicity of the structure and convenient use.

[0052] Among them, the first bending die 8 includes a limit base 801. Rotating seats 802 are movably installed on the opposite sides at both ends of the limit base 801 through bearings. Bending die seats 803 are fixedly installed on the opposite sides of the rotating seats 802. Infrared thermopile sensors 806 are embedded and installed inside the rotating seats 802. A number of arc-shaped electromagnetic induction heating coil discs 805 are installed inside the bending die seats 803. A bending groove is opened on the outer side of the bending die seats 803. The specification dimensions of the bending die seats 803 are adapted to the specification dimensions of the bending die head 701. A number of second hexagon socket head bolts 804 are movably installed through the bottom of the limit base 801. The specification dimensions of the second hexagon socket head bolts 804 are adapted to the specification dimensions of the thread groove 603. The specification dimensions of the limit base 801 are adapted to the specification dimensions of the installation groove 101. The notch of the bending die seat 803 is on the same horizontal plane as the workbench 1. Bolt holes adapted to the second hexagon socket head bolts 804 are opened inside the limit base 801. The second hexagon socket head bolts 804 are linearly and evenly distributed inside the limit base 801. The arc-shaped electromagnetic induction heating coil discs 805 are located inside the bending die seats 803 in a curved arc shape. The arc-shaped electromagnetic induction heating coil discs 805 are linearly and evenly distributed inside the bending die seats 803. The outer surface of the bending die seat 803 is arc-shaped, and the angle range of this arc includes 90°, 120°, and 135°.

[0053] In this implementation scheme, when the bending die base 803 and the bending die head 701 are bent, they are under pressure, which causes the steel plate to be on the same horizontal plane as the bending die base 803 and the workbench 1, and generally warps one end of the steel plate. The other end is clamped and fixed by the auxiliary positioning mechanism 11, so as to cooperate with the bending operation. When bending, the bending die base 803 is first with the notch facing up. As the bending die head 701 moves down, the steel plate is gradually bent, and the bending die base 803 rotates to a certain extent with the support of the rotating seat 802, and the steel plate is gradually bent as the bending die head 701 and the spring limit telescopic mechanism 703 buffer and move down, so as to carry out the bending. The installation of the hexagon socket head cap screw 804 facilitates replacement. At the same time, the hexagon socket head cap screw 804 can pass through the bolt hole of the mounting seat 509 to be used for installing and changing the bending position, which is convenient for carrying out different bending operations. The arc-shaped electromagnetic induction heating coil disk 805 heats the steel structure at the arc surface position of the bending die base 803. The arc-shaped electromagnetic induction heating coil disk 805 adopts an external electromagnetic induction heating controller, an internal rectifier circuit, an inverter circuit, a control circuit, a drive circuit, a protection circuit and other parts to carry out electromagnetic induction control on the arc-shaped electromagnetic induction heating coil disk 805 and heat the steel structure. This implementation scheme only shows the position and distribution of the arc-shaped electromagnetic induction heating coil disk 805. The material of the bending die base 803 is one of plastic, ceramic, glass fiber reinforced composite material and non-magnetic metal alloy to ensure that the heating during the bending process is not blocked and facilitate the cooperation operation. In addition, when a larger right-angle bending is carried out, two bending dies 8 can be installed inside the installation groove 101. One bending die base 803 is a pre-bent arc, and one bending die base 803 is the final bending angle. Only need to pre-bend the steel plate first, then move the steel plate to the bending position, start the hydraulic telescopic rod 506 to push the sliding seat 505 to move, and then move through the gantry 501 to make the first bending head 7 move, and then carry out step-by-step bending, so as to facilitate the cooperation with the pre-bending operation.

[0054] Among them, the bending die II 9 includes a base I 901. Inner hexagonal bolts III 902 are movably inserted into the inner sides of both ends of the base I 901. The specification dimensions of the inner hexagonal bolts III 902 are adapted to the specification dimensions of the thread grooves 603. Bolt holes adapted to the inner hexagonal bolts III 902 are provided inside both ends of the base I 901. A number of adjusting holes I 903 are provided inside both sides of the top end of the base I 901. Steel bar limiting rollers 907 are movably inserted into the inner sides of the opposite sides of the adjusting holes I 903. Both ends of the steel bar limiting rollers 907 are fixed to the opposite sides of the base I 901 by bolts. The steel bar limiting rollers 907 are composed of a support shaft and bending rollers movably supported by bearings. A chute 904 is provided in the middle part of the top end of the base I 901. A slide bar 905 is slidably installed inside the chute 904. Spring limiting and telescoping mechanisms II 908 are fixedly installed at the bottoms of both ends of the slide bar 905. The bottoms of the spring limiting and telescoping mechanisms II 908 are fixedly installed at the bottom of the inner cavity of the base I 901. A steel bar bending roller sleeve 906 is movably sleeved outside the slide bar 905 through a bearing. The bending head II 10 includes a base II 1001. Inner hexagonal bolts IV 1002 are movably inserted into the inner sides of both ends of the base II 1001. Bolt holes adapted to the inner hexagonal bolts IV 1002 are provided inside both ends of the base II 1001. The specification dimensions of the inner hexagonal bolts IV 1002 are adapted to the specification dimensions of the thread grooves 603. A number of adjusting holes II 1003 are provided inside both sides of the top end of the base II 1001. The adjusting holes II 1003 are linearly and evenly distributed inside both ends of the base II 1001. A bending head III 1004 is movably installed inside the base II 1001. The bending head III 1004 is fixed inside the base II 1001 by bolts passing through the adjusting holes II 1003. The specification dimensions of the base II 1001 and the base I 901 are adapted to the specification dimensions of the installation groove 101. The specification dimensions of the bending head III 1004 are adapted to the specification dimensions of the base I 901.

[0055] In this implementation scheme, the bending die II 9 and the bending head II 10 are matching bending components. For example, when a steel bar is placed at the notch grooves of the steel bar limiting rollers 907 and the steel bar bending roller sleeve 906, and the bending head II 10 is installed at the bottom of the mounting seat I 509, when moving downward, the bending head III 1004 contacts the top of the steel bar, and then moves downward, promoting the steel bar bending roller sleeve 906 and the slide bar 905 to move downward, and promoting the slide bar 905 to move downward inside the chute 904. And the slide bar 905 moves downward elastically supported by the spring limiting and telescoping mechanism II 908, so as to bend the steel bar into a Ω shape for the production of different components. Thus, a matching die is selected for installation and use, and multiple bendings are carried out, and different bending requirements can be adjusted and adapted, so as to operate with a stable structure.

[0056] Among them, the auxiliary positioning mechanism 11 includes an L-shaped plate 1101. A third base 1107 is fixedly installed at the bottom of the L-shaped plate 1101. A number of clamping bolts 1102 are threadedly connected inside the L-shaped plate 1101. A bearing support 1103 is sleeved on the outer side of the bottom end of the clamping bolt 1102. A first connecting plate 1104 is fixedly installed at the bottom of the bearing support 1103. A number of third spring limit telescopic mechanisms 1105 are fixedly installed at the bottom of the first connecting plate 1104. The third spring limit telescopic mechanisms 1105 are linearly and evenly distributed at the bottom of the first connecting plate 1104. A limit clamping plate 1106 is fixedly installed at the bottom of the third spring limit telescopic mechanisms 1105. The specification and dimension of the third base 1107 are adapted to those of the installation groove 101. A number of fifth hexagon socket head cap screws 1108 are movably inserted into the third base 1107. The specification and dimension of the fifth hexagon socket head cap screw 1108 are adapted to those of the thread groove 603. A bolt hole adapted to the fifth hexagon socket head cap screw 1108 is opened inside the third base 1107. The fifth hexagon socket head cap screws 1108 are linearly and evenly distributed inside the third base 1107. There are two specifications of the auxiliary positioning mechanism 11, and the two auxiliary positioning mechanisms 11 are axially symmetrically distributed on the top of the workbench 1.

[0057] In this implementation scheme, the function of the auxiliary positioning mechanism 11 is to perform end limit on the required plate, so as to assist the bending operation, and adjust the distance according to the installation position of the installation groove 101, so as to ensure the stability during bending.

[0058] A process for suppressing residual stress of steel structural parts in a nuclear reactor. This process for suppressing residual stress of steel structural parts in a nuclear reactor applies a bending device for producing steel structural parts in a nuclear reactor, and includes the following steps:

[0059] S1. Perform segmented cutting on the steel plates, steel sections, steel bars and steel rods that need to be bent. When bending a steel plate, determine the angle of die processing according to the processing requirements of the fittings. Common bending angles are 90°, 120° and 135°. Then install the first bending die 8 inside the installation groove 101, install the first bending head 7 at the output end of the bending mechanism 5, and symmetrically install the two auxiliary positioning mechanisms 11 on both sides of the first bending die 8 and the first bending head 7;

[0060] S2. Then, select the bending to determine the bending radius according to the thickness of the bent steel. For low-carbon steel, when the thickness is 1-2 mm, the bending radius is 1-1.5 times the material thickness; when the thickness is 2-4 mm, the bending radius is about 1.5-2 times the thickness; when the thickness is 4-6 mm, the bending radius is 2-3 times the thickness; when the thickness is greater than 6 mm, the bending radius is not less than 3 times the thickness. For high-strength alloy steel, in order to prevent cracking of the material during bending, the bending radius is larger than that of low-carbon steel. For example, for high-strength alloy steel with a thickness of 1-2 mm, the bending radius is 1.5-2 times the material thickness; as the thickness increases, the multiple relationship between the bending radius and the thickness will also increase accordingly. Then, after selecting the die and processing mode, place the steel plate in the processing position;

[0061] S3. Then, according to the thickness of the steel plate, rotate the clamping bolt 1102 to make the clamping bolt 1102 rotate with the bearing support 1103 and extend downward, and squeeze the connecting plate one 1104, the spring limit telescopic mechanism three 1105 and the limit clamping plate 1106 to move downward, and clamp the outside of the steel plate. Then, control the hydraulic lifting mechanism 6 corresponding to the first bending head 7 and the first bending die 8 to extend, so that the second hydraulic telescopic rod 601 is pushed out, the first bending die 8 is pushed out, and the bending surface of the bending die base 803 is flush with the plane of the workbench 1 and the bottom of the steel plate. Then, start the electric control high-precision hydraulic cylinder telescopic mechanism 502 to extend, and push the connecting frame 508 and the first mounting seat 509 to move downward, thereby promoting the spring limit telescopic mechanism one 703 and the bending die head 701 to move downward, so as to contact the top of the steel plate and gradually move downward to gradually bend the steel plate to the position where it fits the bending die base 803;

[0062] S4. At the same time, the arc-shaped electromagnetic induction heating coil disc 805 is started to electromagnetically heat the bent part of the steel plate, and the temperature is measured by the infrared thermopile sensor 806. By controlling the power of the arc-shaped electromagnetic induction heating coil disc 805 and combining the measured temperature of the infrared thermopile sensor 806, the bending temperature of the steel structure steel plate used in the nuclear reactor is controlled. For example, for high-strength low-alloy steel, the heating temperature is controlled in the range of 600-900 °C. For example, when bending Q460 steel, the heating temperature is selected to be about 700-850 °C; for higher-strength alloy steel, such as some steels containing more alloying elements such as chromium and molybdenum, the heating temperature needs to reach 800-900 °C to ensure that the material has good plasticity and is convenient for bending and forming. By controlling the slow extension of the electric control high-precision hydraulic cylinder telescopic mechanism 502, the bending speed and the heating speed are linearly increased to avoid the situation of too fast temperature and bending speed. The operation of the two auxiliary positioning mechanisms 11 clamping the steel plate is suitable for bending the middle part of the steel plate into shape. If a right-angle bend is required, replace the first bending head 7 and the first bending die 8 with right angles, and clamp and fix one end through the auxiliary positioning mechanism 11;

[0063] S5. Then, after the bending is completed, the cooling rate has a great influence on the performance of the high-strength steel structure steel used in the nuclear reactor. Usually, it is necessary to control the cooling rate moderately to avoid excessive internal stress or abnormal microstructure transformation. In the production after bending, air cooling or slow cooling methods need to be adopted. During air cooling, the cooling rate is relatively slow, generally about 5 - 15 °C per minute; for slow cooling, the workpiece can be placed in heat-insulating materials to make it cool slowly, and the cooling rate is in the range of 1 - 5 °C per minute. By reducing the bending speed, heating at the bending area, and slowly reducing the temperature, the internal stress generated in the steel structure in the nuclear reactor during the bending process can be reduced to increase the service strength. And by adopting the secondary bending process, when reducing the bending speed, after a slow first bending, the rigid bending contact force is reduced by the spring limit telescopic mechanism 703, and the workpiece is gradually heated during the bending process for secondary bending, thereby reducing the bending stress to ensure the quality during the bending process and increasing the yield rate.

[0064] Further explanation: Unless otherwise clearly specified and defined, the above fixed connection should be understood in a broad sense. For example, it can be welding, gluing, or integrally formed setting, etc., which are common means well-known to those skilled in the art.

[0065] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes should be covered within the protection scope of the present invention.

Claims

1. A bending device for producing steel structural parts in nuclear reactors, comprising a workbench (1), a hydraulic lifting mechanism (6), a second bending die (9), a second bending head (10) and an auxiliary positioning mechanism (11), characterized in that: The top of the workbench (1) is provided with a plurality of mounting grooves (101), the bottom of the inner cavity of the mounting groove (101) is provided with a plurality of through holes (103), the bottom of the workbench (1) is fixedly provided with a bottom bracket (102), the top of the workbench (1) is fixedly provided with two sliding support mechanisms (2), the inner sides of the two sliding support mechanisms (2) are movably provided with a bending mechanism (5), the output end of the bending mechanism (5) is provided with a bending head (7), the interior of the mounting groove (101) is movably provided with a bending mold (8), the bottom of the workbench (1) is fixedly provided with a reinforcement mechanism (3), and the top of the workbench (1) is fixedly provided with a control console (4); The hydraulic lifting mechanism (6) comprises a second mounting plate (608), a third hydraulic telescopic rod (607) is fixedly mounted on one side of the second mounting plate (608), a sealing piston (609) is fixedly mounted on the output end of the third hydraulic telescopic rod (607), a connecting tube (606) is movably sleeved on the outer side of the sealing piston (609), the output end of the connecting tube (606) is connected to a synchronous isobaric hydraulic pipe (604), an electric control valve (605) is movably mounted on the inner side of the synchronous isobaric hydraulic pipe (604), the end of the synchronous isobaric hydraulic pipe (604) away from the connecting tube (606) is connected to a second hydraulic telescopic rod (601), a threaded groove (603) is provided on the top of the output end of the second hydraulic telescopic rod (601), a first mounting plate (602) is fixedly mounted on the bottom of the second hydraulic telescopic rod (601), and the hydraulic lifting mechanism (6) is linearly and evenly distributed inside the reinforcement mechanism (3).

2. A bending device for producing steel structural parts in nuclear reactors according to claim 1, characterized in that: The mounting grooves (101) are linearly and evenly distributed on the top of the workbench (1); the through holes (103) are linearly and evenly distributed inside the mounting grooves (101); the two sliding support mechanisms (2) each comprise a sliding rail (201) and a reinforcing rib (202); the reinforcing rib (202) is linearly and symmetrically fixedly mounted on both sides of the sliding rail (201); and the sliding rail (201) is fixedly mounted on the top of the workbench (1).

3. The bending device for producing steel structural parts in nuclear reactors according to claim 1, characterized in that: The reinforcement mechanism (3) comprises an installation box (301), the installation box (301) is fixedly installed at the bottom of the workbench (1), a plurality of reinforcement frames (302) are fixedly installed at the bottom of the installation box (301), the reinforcement frames (302) are linearly and evenly distributed at the bottom of the installation box (301), the specification and size of the output end of the second hydraulic telescopic rod (601) are compatible with the specification and size of the through hole (103), the hydraulic jacking mechanism (6) is located inside the installation box (301), the output end of the second hydraulic telescopic rod (601) movably passes through the installation box (301) and movably extends to the inside of the installation slot (101), and the third hydraulic telescopic rod (601) 07) and the mounting plate 1 (602) are fixedly mounted inside the mounting box (301) by bolts and brackets, the distance between the output end of the synchronous isobaric hydraulic pipe (604) and the hydraulic telescopic rod 2 (601) is the same as the distance between the output end of the connecting tube (606), and the hydraulic telescopic rod 2 (601) is evenly distributed linearly and equidistantly with the synchronous isobaric hydraulic pipe (604), and hydraulic oil is provided inside the connecting tube (606), the synchronous isobaric hydraulic pipe (604) and the hydraulic telescopic rod 2 (601), and the hydraulic telescopic rod 2 (601) has two specifications, one is a hydraulic rod in a multi-cylinder synchronous hydraulic system, and the other is a hydraulic rod with high-precision control of a single cylinder.

4. The bending device for producing steel structural parts in nuclear reactors according to claim 2, characterized in that: The bending mechanism (5) comprises a door frame (501), a slide seat (505) is fixedly mounted at the bottom of both ends of the door frame (501), a slide column (507) is movably sleeved inside the slide seat (505), a hydraulic telescopic rod (506) is fixedly mounted on one side of the slide seat (505), the slide seat (505) is slidably mounted inside the sliding rail (201), one end of the hydraulic telescopic rod (506) away from the slide seat (505) is fixedly mounted inside the sliding rail (201), both ends of the slide column (507) are fixedly mounted inside the sliding rail (201), and the door frame (501) is fixedly mounted on the sliding rail (201). 1) An electrically controlled high-precision hydraulic cylinder telescopic mechanism (502) is fixedly installed on the bottom surface of the top, a connecting frame (508) is fixedly installed on the output end of the electrically controlled high-precision hydraulic cylinder telescopic mechanism (502), a mounting seat (509) is fixedly installed on the bottom of the connecting frame (508), a sliding rod (503) is movably sleeved on the inner sides of both ends of the mounting seat (509), the top of the sliding rod (503) is fixedly installed on the bottom surface of the top of the door frame (501), and a reinforcing seat (504) is fixedly installed on the bottom end of the sliding rod (503), and the reinforcing seat (504) is fixedly installed on the inner side of the door frame (501).

5. The bending device for producing steel structural parts in nuclear reactors according to claim 4, characterized in that: The bending head (7) comprises a bending die (701), and a plurality of spring limiting telescopic mechanisms (703) are fixedly installed on the top of the bending die (701). The spring limiting telescopic mechanisms (703) are linearly and evenly distributed on the top of the bending die (701). The internal thread of the top of the spring limiting telescopic mechanism (703) is connected with a hexagon socket bolt (702). The hexagon socket bolt (702) movably passes through a mounting seat (509) and extends to the inside of the spring limiting telescopic mechanism (703). The inside of the mounting seat (509) is provided with a bolt hole matched with the hexagon socket bolt (702). The specification size of the hexagon socket bolt (702) is matched with the specification size of the thread groove (603). One end of the bending die (701) is an arc surface, and the other end is a right angle surface.

6. A bending device for producing steel structural parts in nuclear reactors according to claim 5, characterized in that: The bending die one (8) comprises a limiting base (801), and a rotating base (802) is movably mounted on opposite sides of both ends of the limiting base (801) through bearings, and a bending die base (803) is fixedly mounted on the opposite side of the rotating base (802), and an infrared thermopile sensor (806) is embedded in the rotating base (802), and a plurality of arc-shaped electromagnetic induction heating coil disks (805) are mounted in the bending die base (803), and a bending groove is provided on the outer side of the bending die base (803), and the specification and size of the bending die base (803) are matched with the specification and size of the bending die head (701), and a plurality of hexagon socket head bolts (804) are movably mounted through the bottom of the limiting base (801), and the specification and size of the hexagon socket head bolts (804) are consistent with the specification and size of the threaded The size of the groove (603) is matched with the size of the limiting base (801) and the size of the installation groove (101). The notch of the bending die base (803) and the workbench (1) are in the same horizontal plane. The inside of the limiting base (801) is provided with a bolt hole matched with the second hexagon socket bolt (804). The second hexagon socket bolt (804) is linearly and evenly distributed inside the limiting base (801). The arc-shaped electromagnetic induction heating coil disk (805) is in a curved arc shape and is located inside the bending die base (803). The arc-shaped electromagnetic induction heating coil disk (805) is linearly and evenly distributed inside the bending die base (803). The outer surface of the bending die base (803) is arc-shaped, and the angle range of the arc includes 90°, 120° and 135°.

7. The bending device for producing steel structural parts in nuclear reactors according to claim 1, characterized in that: The bending mold 2 (9) includes a base 1 (901), and the inner sides of both ends of the base 1 (901) are movably connected with hexagon socket bolts 3 (902), and the specifications and sizes of the hexagon socket bolts 3 (902) are compatible with the specifications and sizes of the thread groove (603). The interiors of both ends of the base 1 (901) are provided with bolt holes that are compatible with the hexagon socket bolts 3 (902). The interiors of both sides of the top of the base 1 (901) are provided with a plurality of adjustment holes 1 (903), and the interiors of the opposite sides of the adjustment holes 1 (903) are movably connected with steel bar limiting rollers (907). The inner parts of the two ends of the steel bar limiting roller (907) are fixed to the opposite sides of the base one (901) by bolts. The steel bar limiting roller (907) is composed of a support shaft and a bending roller movably supported by a bearing. A slide groove (904) is provided in the middle part of the top of the base one (901). A slide bar (905) is slidably installed inside the slide groove (904). The bottoms of the two ends of the slide bar (905) are fixedly installed with a spring limiting telescopic mechanism two (908). The bottom of the spring limiting telescopic mechanism two (908) is fixedly installed at the bottom of the inner cavity of the base one (901). The outer side of the slide bar (905) is movably connected to a steel bar bending roller sleeve (906) through a bearing, and the bending head 2 (10) includes a base 2 (1001), and the interiors of both ends of the base 2 (1001) are movably connected with hexagon socket bolts 4 (1002), and the interiors of both ends of the base 2 (1001) are provided with bolt holes that are compatible with the hexagon socket bolts 4 (1002), and the specifications and dimensions of the hexagon socket bolts 4 (1002) are compatible with the specifications and dimensions of the thread groove (603), and the interiors of both sides of the top of the base 2 (1001) are provided with a plurality of adjustment screws. Hole 2 (1003), the adjustment holes 2 (1003) are linearly and evenly distributed inside the two ends of the base 2 (1001), and a bending head 3 (1004) is movably installed on the inner side of the base 2 (1001), and the bending head 3 (1004) is fixed to the inner side of the base 2 (1001) by bolts passing through the adjustment holes 2 (1003), the specifications and dimensions of the base 2 (1001) and the base 1 (901) are compatible with the specifications and dimensions of the installation groove (101), and the specifications and dimensions of the bending head 3 (1004) are compatible with the specifications and dimensions of the base 1 (901).

8. The bending device for producing steel structural parts in nuclear reactors according to claim 6, characterized in that: The auxiliary positioning mechanism (11) comprises an L-shaped plate (1101), a base three (1107) is fixedly installed at the bottom of the L-shaped plate (1101), a plurality of clamping bolts (1102) are connected to the inner thread of the L-shaped plate (1101), a bearing support (1103) is sleeved on the outer side of the bottom end of the clamping bolt (1102), a connecting plate one (1104) is fixedly installed at the bottom of the bearing support (1103), a plurality of spring limiting telescopic mechanisms three (1105) are fixedly installed at the bottom of the connecting plate one (1104), the spring limiting telescopic mechanisms three (1105) are linearly and evenly distributed at the bottom of the connecting plate one (1104), and the bottom of the spring limiting telescopic mechanisms three (1105) A limited clamping plate (1106) is fixedly installed, the size of the base three (1107) is compatible with the size of the installation groove (101), a plurality of hexagon socket bolts (1108) are movably inserted inside the base three (1107), the size of the hexagon socket bolts (1108) is compatible with the size of the threaded groove (603), a bolt hole compatible with the hexagon socket bolts (1108) is opened inside the base three (1107), the hexagon socket bolts (1108) are linearly and evenly distributed inside the base three (1107), the auxiliary positioning mechanism (11) has two specifications, and the two auxiliary positioning mechanisms (11) are axially symmetrically distributed on the top of the workbench (1).

9. A process for suppressing residual stress in steel structural parts in nuclear reactors, characterized in that: The bending device for producing steel structural parts in a nuclear reactor as claimed in claim 8 is applied, comprising the following steps: S1. Cut the steel plates, steel sections, steel bars and steel rods to be bent into sections. For example, when bending the steel plates, determine the angle of the mold processing according to the processing requirements of the accessories. Common bending angles are 90°, 120° and 135°. Then, install the bending mold 1 (8) on the inner side of the installation groove (101), install the bending head 1 (7) at the output end of the bending mechanism (5), and symmetrically install two auxiliary positioning mechanisms (11) on both sides of the bending mold 1 (8) and the bending head 1 (7); S2. Then, according to the thickness of the steel to be bent, the bending radius is selected and determined. For low-carbon steel, when the thickness is 1-2 mm, the bending radius is 1-1.5 times the thickness of the material; when the thickness is 2-4 mm, the bending radius is about 1.5-2 times the thickness; when the thickness is 4-6 mm, the bending radius is 2-3 times the thickness; when the thickness is greater than 6 mm, the bending radius is not less than 3 times the thickness. For high-strength alloy steel, in order to prevent the material from cracking during the bending process, the bending radius is larger than that of low-carbon steel. For example, for high-strength alloy steel with a thickness of 1-2 mm, the bending radius is 1.5-2 times the thickness of the material; as the thickness increases, the multiple relationship between the bending radius and the thickness will also increase accordingly. After selecting the mold and processing mode, put the steel plate into the processing position; S3, then according to the thickness of the steel plate, the clamping bolt (1102) is rotated to cause the clamping bolt (1102) to extend downward along with the rotation of the bearing support (1103), and to squeeze the connecting plate 1 (1104), the spring limit telescopic mechanism 3 (1105) and the limit clamping plate (1106) to move downward, and clamp the outer side of the steel plate, and then control the hydraulic jacking mechanism (6) corresponding to the bending head 1 (7) and the bending die 1 (8) to extend, so as to cause the hydraulic telescopic rod 2 (601) to push up The bending die (8) is pushed out, and the bending surface of the bending die seat (803) is flush with the plane of the workbench (1) and the bottom of the steel plate, and then the electric-controlled high-precision hydraulic cylinder telescopic mechanism (502) is started to extend, and the connecting frame (508) and the mounting seat (509) are pushed down, thereby prompting the spring-limited telescopic mechanism (703) and the bending die head (701) to move down, thereby contacting the top of the steel plate, and gradually moving down to gradually bend the steel plate to a position that fits the bending die seat (803); S4. At the same time, the arc-shaped electromagnetic induction heating coil disk (805) is started to electromagnetically heat the bending part of the steel plate, and the temperature is measured by the infrared thermopile sensor (806). By controlling the power of the arc-shaped electromagnetic induction heating coil disk (805) and combining the measured temperature of the infrared thermopile sensor (806), the bending temperature of the steel plate used for the steel structure in the nuclear reactor is controlled. For example, for high-strength low-alloy steel, the heating temperature is controlled within the range of 600-900°C. For example, when bending Q460 steel, the heating temperature is selected to be around 700-850°C; for higher strength alloy steels, such as some steels containing more alloy elements such as chromium and molybdenum, the heating temperature needs to reach 800-900°C to ensure that the material has good plasticity and is easy to bend and form. By controlling the slow extension of the electronically controlled high-precision hydraulic cylinder telescopic mechanism (502), the bending speed and the heating speed are linearly increased to avoid the situation where the temperature and the bending speed are too fast. The operation of clamping the steel plate with two auxiliary positioning mechanisms (11) is suitable for bending the steel plate in the middle. If right-angle bending is performed, the right-angle bending head (7) and the bending mold (8) are replaced, and one end is clamped and fixed by the auxiliary positioning mechanism (11); S5. After the bending is completed, the cooling speed has a great influence on the performance of high-strength steel structures used in nuclear reactors. It is usually necessary to control the cooling speed to be moderate to avoid excessive internal stress or abnormal structural transformation. In the production after bending, air cooling or slow cooling is required. When air cooling, the cooling speed is relatively slow, generally around 5-15°C per minute; slow cooling can be achieved by placing the workpiece in an insulating material to slowly cool it down, with a cooling speed in the range of 1-5°C per minute. The bending speed is reduced, the bending point is heated, and the temperature is slowly cooled to reduce the internal stress of the steel structure in the nuclear reactor generated during the bending process, so as to increase the strength of use, and a secondary bending process is adopted. When the bending speed is reduced, after a slow bending, the rigid bending contact force is reduced by a spring limit telescopic mechanism (703), and the workpiece is gradually heated during the bending process for a secondary bending, thereby reducing the bending stress, ensuring the quality of the bending process, and increasing the yield rate.

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