CN113593737A

CN113593737A - Automatic discharging device

Info

Publication number: CN113593737A
Application number: CN202110796855.XA
Authority: CN
Inventors: 张丽娜; 曹云; 李林玉; 朱世峰; 翟利芳; 胡瑞荣
Original assignee: Shanghai Institute of Applied Physics of CAS
Current assignee: Shanghai Institute of Applied Physics of CAS
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2021-11-02
Anticipated expiration: 2041-07-14
Also published as: CN113593737B

Abstract

The invention relates to an automatic discharging device, comprising: the shielding cylinder assembly comprises a shielding cylinder and a discharge pipe; the driving mechanism is fixed on the outer side of the wall of the shielding cylinder, and a transmission shaft of the driving mechanism penetrates through the wall of the shielding cylinder and extends into the shielding cylinder; the guide mechanism is connected to the lower end of the shielding cylinder and communicated with the interior of the shielding cylinder; one end of the actuating mechanism is connected with a transmission shaft of the driving mechanism, and the other end of the actuating mechanism extends downwards out of the guide mechanism; the jacking mechanism is fixed at the lower end of the discharging pipe; one end of the discharge pipe penetrates through the wall of the shielding cylinder and is discharged, and the other end of the discharge pipe axially extends downwards from the inside of the shielding cylinder to form the guide mechanism. The automatic discharging device controls the movement of the actuating mechanism through the driving mechanism, ensures the up-and-down movement of the actuating mechanism through the guide mechanism, and finishes the picking and conveying of spent fuel balls through the cooperation with the jacking mechanism, thereby reducing the intervention of other equipment and reducing the space requirement of the equipment.

Description

Automatic discharging device

Technical Field

The present invention relates to the field of nuclear reactor equipment, and more particularly to an automatic unloading device for a nuclear reactor.

Background

Spent fuel refers to nuclear fuel in a nuclear fuel assembly that has been discharged from a reactor after nuclear reactions have occurred in a nuclear reactor via neutron bombardment to a burn-up depth that is designed to discharge the fuel and is no longer in use in the reactor.

At present, the fuel forms adopted by reactors already in service or under development at home and abroad are mainly divided into two forms, namely liquid fuel and solid fuel, and the main structural form of the solid fuel can refer to fuel assemblies of a pressurized water reactor and spherical fuel elements of a high-temperature gas cooled reactor. Compared with fuel assemblies of liquid fuel and pressurized water reactors, the spherical fuel element has the advantages that the fuel can be changed without stopping the reactor, and the discharging device is one of important devices for realizing the function. As a representative of the use of spherical fuel elements, the high temperature gas cooled reactor developed by the university of qinghua has successfully carried out on-line refueling of spherical fuel elements in the reactor.

The development and application of the unloading equipment mainly consider the spent fuel pickup by means of strength by combining the characteristics of the high-temperature gas cooled reactor. However, for a Thorium-based Molten Salt Reactor Nuclear power System (TMSR), one loop is cooled with Molten Salt, the gas is merely blanketed over the Molten Salt as a shielding gas, and the internal pressure is small. Therefore, the unloading equipment of the high-temperature gas cooled reactor is not suitable for the TMSR molten salt reactor from the viewpoint of the operating environment. In addition, other discharging devices capable of meeting the discharging requirement of the TMSR molten salt reactor do not exist in the prior art.

Disclosure of Invention

The invention aims to provide an automatic discharging device to solve the problem of discharging spent fuel in a TMSR molten salt pile under the environment of narrow space, high temperature, molten salt and irradiation.

The invention provides an automatic discharging device, comprising:

the shielding cylinder assembly comprises a shielding cylinder and a discharge pipe;

the driving mechanism is fixed on the outer side of the wall of the shielding cylinder, and a transmission shaft of the driving mechanism penetrates through the wall of the shielding cylinder and extends into the shielding cylinder;

the guide mechanism is connected to the lower end of the shielding cylinder and communicated with the interior of the shielding cylinder;

one end of the actuating mechanism is connected with a transmission shaft of the driving mechanism, and the other end of the actuating mechanism extends downwards out of the guide mechanism;

the jacking mechanism is fixed at the lower end of the discharging pipe;

one end of the discharge pipe penetrates through the wall of the shielding cylinder and is discharged, and the other end of the discharge pipe axially extends downwards from the inside of the shielding cylinder to form the guide mechanism.

Furthermore, the shielding cylinder is provided with a mounting opening and a cover plate, the actuating mechanism is mounted on the transmission shaft through the mounting opening, and the cover plate is fixed on the outer side of the cylinder wall of the shielding cylinder and covers the mounting opening.

Furthermore, a reinforcing rib is arranged at the joint of the discharge pipe and the shielding cylinder.

Further, the driving mechanism comprises a motor, a speed reducer and a magnetic coupler which are sequentially connected, and the magnetic coupler is fixed on the outer side wall of the shielding cylinder.

And the two ends of the bracket are respectively connected with the magnetic coupler and the outer wall of the shielding cylinder.

Furthermore, the actuating mechanism comprises a crank, a connecting rod, a sliding block and a ball spoon, one end of the crank is connected with the transmission shaft, the other end of the crank is connected with one end of the connecting rod, the other end of the connecting rod is connected with the sliding block, and the ball spoon is fixed at the bottom end of the sliding block.

Furthermore, the guiding mechanism comprises a supporting cylinder and at least one roller assembly, the upper end of the supporting cylinder is connected with the lower end of the shielding cylinder, and the at least one roller assembly is fixed on the inner wall of the supporting cylinder.

Furthermore, the roller assembly comprises two groups of symmetrical roller supports, rollers and roller shafts, the roller supports are arranged around the executing mechanism and fixed on the supporting barrel, and the rollers are arranged on the roller supports through the roller shafts.

Further, a gap is reserved between the actuating mechanism and the roller.

Furthermore, the guide mechanism further comprises a cavity filling assembly and a supporting plate, the cavity filling assembly is filled in the supporting cylinder, and the supporting plate is supported at the bottom end of the cavity filling assembly and is fixed with the supporting cylinder.

Further, the jacking mechanism comprises a base plate assembly and a rotating shaft assembly, the base plate assembly is fixed at the lower end of the discharge pipe, and the rotating shaft assembly is rotatably connected with the base plate assembly.

Further, the base plate assembly comprises a welding plate, an adjusting plate and a fixing shaft, the welding plate is welded at the lower end of the discharge tube, the adjusting plate is connected to the welding plate through bolts and positioned through two positioning pins, the fixing shaft is welded to the adjusting plate, and the rotating shaft assembly is rotatably connected with the fixing shaft.

Further, the outer end face of the fixed shaft is provided with a check bolt, and a gap is reserved between the check bolt and the rotating shaft assembly.

Further, the pivot subassembly includes the pivot and fixes pin, balancing weight and ejector pin in the pivot, the pivot with the fixed axle rotates and is connected.

Further, the ball spoon is provided with a notch for the ejector rod to pass through.

According to the automatic discharging device, the driving mechanism controls the movement of the actuating mechanism, the guide mechanism ensures the up-and-down movement of the actuating mechanism, the lifting mechanism is matched with the lifting mechanism to complete the picking and conveying of spent fuel balls, and the driving mechanism is only required to operate all the time to complete the automatic picking, conveying and discharging of the spent fuel balls, so that the intervention of other equipment is reduced, and the space requirement of the equipment is reduced; the effective isolation of the internal atmosphere and the external atmosphere of the reactor is ensured through the magnetic coupler, so that the automatic discharging device can be better applied to the operating environment of the TMSR molten salt reactor. Meanwhile, the automatic unloading device is different from unloading devices in all nuclear power stations and nuclear reaction devices in active service, and the application of the automatic unloading device provides practical reference for better expanding the development of new structures of nuclear reactors.

Drawings

Fig. 1 is a schematic structural diagram of an automatic discharging device provided in an embodiment of the present invention;

FIG. 2 is a schematic half-section view of FIG. 1;

FIG. 3 is a schematic structural view of a driving mechanism of the automatic discharging apparatus of FIG. 1;

FIG. 4 is a schematic structural view of an actuator of the automatic discharging device of FIG. 1;

FIG. 5 is a schematic structural view of a guide mechanism of the automatic discharging apparatus of FIG. 1;

FIG. 6 is a cross-sectional view B-B of FIG. 1;

FIG. 7 is a schematic structural view of a jacking mechanism of the automatic discharging device of FIG. 1;

FIG. 8 is a schematic structural view of a base plate assembly of the jacking mechanism of FIG. 7;

FIG. 9 is a schematic structural view of a rotating shaft assembly of the jacking mechanism in FIG. 7;

fig. 10 is a schematic view illustrating a spent fuel pick-up operation of the automatic discharge apparatus of fig. 1;

fig. 11 is a schematic diagram of a spent fuel delivery process of the automatic discharging device of fig. 1.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1 and fig. 2, the present invention provides an automatic discharging device, which can be used for a TMSR molten salt reactor, and includes a driving mechanism 1, a shielding cylinder assembly 3, an executing mechanism 4, a guiding mechanism 5 and a jacking mechanism 6, wherein the shielding cylinder assembly 3 includes a shielding cylinder 31 and a discharging pipe 34 welded on the shielding cylinder 31, one end of the discharging pipe 34 extends out from the wall of the shielding cylinder 31, and the other end extends out of the guiding mechanism 5 downwards along the inside of the shielding cylinder 31; the driving mechanism 1 is fixed on the outer side of the wall of the shielding cylinder 31, and a transmission shaft 14 of the driving mechanism extends into the shielding cylinder 31; the guide mechanism 5 is fixed at the lower end of the shielding cylinder 31, and the interior of the guide mechanism is communicated with the interior of the shielding cylinder 31; the actuating mechanism 4 is positioned inside the shielding cylinder 31 and the guide mechanism 5, one end of the actuating mechanism is connected with the transmission shaft 14 of the driving mechanism 1, and the other end of the actuating mechanism extends downwards out of the guide mechanism 5; the jacking mechanism 6 is fixed with the lower end of the discharging pipe 34 extending out of the guide mechanism 5. The shielding cylinder 31 is further provided with a support 2, one end of the support 2 is welded on the shielding cylinder 31, and the other end of the support 2 is fixedly connected with the driving mechanism 1 and used for supporting the driving mechanism. Under the drive of actuating mechanism 1, actuating mechanism 4 can be along vertical direction up-and-down motion in shielding section of thick bamboo 31 to in sending into the discharge tube 34 with the spent fuel ball from the bottom entry, climbing mechanism 6 is arranged in withstanding the spent fuel ball in the discharge tube 34, avoids it to drop from the discharge tube 34, when the spent fuel ball in the discharge tube 34 accumulated to the top of discharge tube 34 all the time, under the effect of gravity, the spent fuel ball can be followed the top export of discharge tube 34 and discharged. The top outlet portion of the discharge pipe 34 may be slightly inclined downward in the horizontal direction, for example, at an inclination angle of 5 °, so that as the spent fuel balls accumulate in the discharge pipe 34, the spent fuel balls at the uppermost stage enter the inclined pipe section and roll forward by their own weight to enter the spent fuel transportation system, thereby achieving automatic discharge.

The shielding cylinder assembly 3 further comprises a cover plate 33, a mounting opening is formed in the shielding cylinder 31 and used for mounting the actuating mechanism 4, and the cover plate 33 is connected to the outer wall of the shielding cylinder 31 through a bolt and covers the mounting opening, so that on one hand, the condition that the atmosphere in the nuclear reactor does not leak out can be guaranteed, and on the other hand, an operation space is also provided for mounting the actuating mechanism 4.

The connection part of the shielding cylinder 31 and the discharge pipe 34 is also provided with a reinforcing rib 35 to increase the strength and rigidity of the connection part and reduce the gas leakage of the shielding cylinder 31 caused by the compression deformation.

The shielding cylinder 31 is further provided with a driving mechanism fixing flange 32 and a guiding mechanism fixing flange 36, and the driving mechanism 1 and the guiding mechanism 5 are fixedly connected with the shielding cylinder 31 through the flanges.

As shown in fig. 3, the driving mechanism 1 includes a motor 11, a speed reducer 12 and a magnetic coupler 13, which are connected in sequence, the magnetic coupler 13 is fixedly connected to the outer wall of the shielding cylinder 31 through a driving mechanism fixing flange 32, and the motor 11 and the speed reducer 12 are isolated from the stack atmosphere through the housing of the magnetic coupler 13, which is beneficial to prolonging the service life thereof and is also convenient for disassembly and maintenance.

As shown in fig. 4, the actuator 4 includes a crank 41, a connecting rod 42, a slider 43, and a key 44. One end of the crank 41 is connected with one end of the transmission shaft 14 through a locking bolt, the other end of the crank 14 is connected with one end of the connecting rod 42 through a bolt, the other end of the connecting rod 42 is connected with the sliding block 43 through a spherical hinge, the tail end of the sliding block 43 extends out of the guide mechanism 5, and the ball key 44 is welded at the tail end of the sliding block 43. Under the drive of the transmission shaft 14, the crank 41 rotates around the transmission shaft 14 in the vertical plane, and transmits torque through the connecting rod 42, so that the sliding block 43 and the ball spoon 44 move up and down in the vertical direction.

As shown in fig. 5, the guide mechanism 5 includes a support cylinder 54 and at least one set of roller assemblies (51, 53, 55), the support cylinder 54 is fixed on the guide mechanism fixing flange 36, the roller assemblies are fixed on the inner wall of the support cylinder 54, and the slider 43 passes through the roller assemblies and is positioned by the roller assemblies. In this embodiment, the roller assemblies include three groups, i.e., a roller assembly I51, a roller assembly II 53, and a roller assembly III 55, which are uniformly arranged in the vertical direction, so that the moving direction of the slider 43 can be more stable.

As shown in fig. 6, each set of roller assemblies includes two roller brackets 531, two rollers 532 and two roller shafts 533, and are symmetrically distributed along the axis of the support cylinder 54. Specifically, the roller bracket 531 is fixed on the support cylinder 54, the rollers 532 are mounted on the roller bracket 531 through the roller shafts 533, the two rollers 532 are disposed around the slider 43, and a gap is reserved between the rollers 532 and the slider 43, so that the slider 43 is prevented from moving laterally while the up-and-down movement is ensured to be smooth. By providing the roller 532, the friction between the slider 43 and the actuator 5 is rolling friction, thereby reducing the friction force during the movement.

The cavity filling assembly 52 is filled in the supporting cylinder 54 and used for inhibiting the molten salt steam from floating upwards so as to reduce the influence of the molten salt steam on other parts. A support plate 56 is secured to the bottom end of the support cylinder 54 for supporting the cavity fill assembly 52 within the support cylinder 54.

As shown in fig. 7, the jacking mechanism 6 includes a base plate assembly 61 and a rotating shaft assembly 62, wherein the base plate assembly 61 is fixed at the lower end of the discharge pipe 34, and the rotating shaft assembly 62 is rotatably connected with the base plate assembly 61, so that the rotating shaft assembly 62 can rotate around the base plate assembly 61. Specifically, as shown in fig. 8 and 9, the base plate assembly 61 includes a welding plate 611, a positioning pin 612, an adjustment plate 613, and a fixing shaft 614. The welding plate 611 is fixed at the lower end of the discharge pipe 34 in a welding mode, bolt holes and positioning holes matched with the positioning pins 612 are formed in the welding plate 611, the adjusting plate 613 is connected to the welding plate 611 through bolts 615, and accurate positioning of the adjusting plate 613 is achieved through matching of the positioning pins 612 and the positioning holes; the fixing shaft 614 is welded to the adjusting plate 613, the rotating shaft assembly 62 is rotatably connected to the fixing shaft 614, and the fixing shaft 614 mainly provides support for the rotating shaft assembly 62 and ensures smooth rotation along the circumference of the fixing shaft 614. A locking bolt 63 is provided on the outer end surface of the fixed shaft 614, and a gap is reserved between the locking bolt and the matching surface of the rotating shaft assembly 62 for limiting the transverse displacement of the rotating shaft assembly 62.

As further shown in fig. 9, the rotating shaft assembly 62 includes a rotating shaft 621, a stop lever 622, a weight 623, and a push rod 624. The stop lever 622, the weight block 623 and the push rod 624 are all welded on the rotating shaft 621 and are installed on the fixed shaft 614 together with the rotating shaft 621, and a gap is reserved between the inner circumference of the rotating shaft 621 and the circumference of the fixed shaft 614 in the radial direction, so that the rotating shaft assembly 62 can rotate along the circumference of the fixed shaft 614. At the initial position, the stop lever 622 will abut against the adjusting plate 613, so that the rotating shaft assembly 62 cannot rotate clockwise but can only rotate counterclockwise, and at this time, the ejector rod 624 can clamp the spent fuel ball in the discharging pipe 34 to prevent the spent fuel ball from falling; when the spent fuel ball enters the discharge pipe 34 from the stack, the push rod 624 is pushed to rotate counterclockwise so as to enter the discharge pipe 34, and then the rotating shaft assembly 62 returns to the initial position under the action of the gravity of the stop lever 622 and the counterweight 623 to continue to block the spent fuel ball in the discharge pipe 34.

The operation of the automatic discharging apparatus of the present invention will be further explained.

As shown in fig. 10, under the driving of the driving mechanism 1, the crank 41 and the connecting rod 42 will drive the slide block 43 and the ball key 44 to make a periodic reciprocating motion, the slide block 43 and the ball key 44 have an upper limit position and a lower limit position, in the upper limit position, the ball key 44 is located between the discharge pipe 34 and the ejector rod 624, at this time, the ball key 44 can send the spent fuel ball 7 into the discharge pipe 34, in the lower limit position, the ball key 44 is located below the ejector rod 624, at this time, the ball key 44 can pick up the spent fuel ball 7 from the stack, and the slide block 43 and the ball key 44 can move up and down between the upper limit position and the lower limit position. The slide 43 and the ball key 44 move downwards from the upper limit position, enter molten salt and then continue to move downwards to the lower limit position. In the process of running in the molten salt, one spent fuel ball 7 enters the spherical spoon 44 under the comprehensive action of the self gravity, the molten salt buoyancy and the mutual extrusion force among the fuel balls, so that the spent fuel is picked up. The ball spoon 44 is provided with a notch which can allow the ejector rod 624 to pass through, so that the ball spoon 44 does not contact with the ejector rod 624 during the up-and-down movement.

As shown in fig. 11, after the spent fuel ball 7 is picked up, the slider 43 and the key 44 carry the spent fuel ball 7 upward from the lower limit position. When the spent fuel ball 7 moves to the ejector rod 624, the rotating shaft assembly 62 rotates anticlockwise due to the extrusion of the spent fuel ball 7, then the sliding block 43 and the ball key 44 carry the spent fuel ball 7 to continue to move upwards, and after the spent fuel ball 7 is separated from the ejector rod 624, the rotating shaft assembly 62 rotates clockwise under the action of gravity and returns to the initial position. Then, the slide block 43 and the ball key 44 carry the spent fuel ball 7 to continue to ascend to the upper limit position and then start to move downwards, at this time, the spent fuel ball 7 enters the discharge pipe 34, under the action of gravity, the spent fuel ball 7 will move downwards and contact with the ejector rod 624, because the ball key 44 does not contact with the ejector rod 624, the ball key 44 will continue to descend through the ejector rod 624, at this time, the spent fuel ball 7 will be separated from the ball key 44 and be pressed against the lower end of the discharge pipe 34 by the ejector rod 624. To this end, the transportation of one spent fuel sphere 7 between the core and the discharge pipe 34 is completed.

The continuous accumulation of spent fuel balls in the discharge tube 34 is accomplished by a continuous cycle of spent fuel ball pick-up and delivery operations. After accumulating to a certain amount, the fuel ball at the top of the discharge pipe 34 starts to roll and advance by means of the gravity of the fuel ball, and enters a spent fuel transportation system, so that automatic discharge is realized.

According to the automatic discharging device provided by the embodiment of the invention, the driving mechanism 1 is used for controlling the movement of the actuating mechanism 4, the guide mechanism 5 is used for ensuring the up-and-down movement of the actuating mechanism 4, and the spent fuel balls are picked up and conveyed by matching with the jacking mechanism 6, so that the intervention of other equipment is reduced, the space requirement of the equipment is reduced, and the spent fuel balls can be automatically picked up, conveyed and discharged only by the continuous operation of the driving mechanism 1; the magnetic coupler 13 ensures effective isolation of internal and external atmospheres of the reactor, so that the automatic discharging device can be better applied to the operating environment of the TMSR molten salt reactor. Meanwhile, the automatic unloading device is different from unloading devices in all nuclear power stations and nuclear reaction devices in active service, and the application of the automatic unloading device provides practical reference for better expanding the development of new structures of nuclear reactors.

The above embodiments are merely preferred embodiments of the present invention, which are not intended to limit the scope of the present invention, and various changes may be made in the above embodiments of the present invention. All simple and equivalent changes and modifications made according to the claims and the content of the specification of the present application fall within the scope of the claims of the present patent application. The invention has not been described in detail in order to avoid obscuring the invention.

Claims

1. An automatic discharge device, comprising:

the jacking mechanism is fixed at the lower end of the discharging pipe;

2. The automatic discharging device according to claim 1, wherein the shielding cylinder is provided with a mounting opening through which the actuator is mounted on the transmission shaft, and a cover plate fixed to an outer side of a cylinder wall of the shielding cylinder and covering the mounting opening.

3. The automatic discharge device according to claim 1, wherein a reinforcing rib is provided at a junction of the discharge pipe and the shielding cylinder.

4. The automatic discharging device according to claim 1, wherein the driving mechanism comprises a motor, a reducer and a magnetic coupler which are connected in sequence, and the magnetic coupler is fixed on the outer side wall of the shielding cylinder.

5. The automatic discharging device according to claim 4, further comprising a bracket, wherein two ends of the bracket are respectively connected with the magnetic coupler and the outer wall of the shielding cylinder.

6. The automatic discharging device according to claim 1, wherein the actuator comprises a crank, a connecting rod, a sliding block and a ball key, one end of the crank is connected with the transmission shaft, the other end of the crank is connected with one end of the connecting rod, the other end of the connecting rod is connected with the sliding block, and the ball key is fixed at the bottom end of the sliding block.

7. The automatic discharge apparatus of claim 1, wherein the guide mechanism comprises a support cylinder and at least one roller assembly, the upper end of the support cylinder is connected to the lower end of the shielding cylinder, and the at least one roller assembly is fixed to the inner wall of the support cylinder.

8. The automatic discharging device according to claim 7, wherein the roller assembly comprises two sets of symmetrical roller brackets, rollers and roller shafts arranged around the actuating mechanism, the roller brackets are fixed on the supporting cylinder, and the rollers are mounted on the roller brackets through the roller shafts.

9. The automatic discharge device of claim 8, wherein a gap is reserved between the actuator and the roller.

10. The automatic discharge device according to claim 7, wherein the guide mechanism further comprises a cavity filling assembly filled inside the support cylinder and a support plate supported at a bottom end of the cavity filling assembly and fixed to the support cylinder.

11. The automatic discharge apparatus of claim 6 wherein said jacking mechanism includes a base plate assembly secured to said discharge tube at a lower end thereof and a pivot assembly pivotally connected to said base plate assembly.

12. The automatic discharge apparatus according to claim 11, wherein said base plate assembly includes a welding plate welded to a lower end of said discharge pipe, an adjustment plate bolted to said welding plate and positioned by a positioning pin, and a fixing shaft welded to said adjustment plate, said rotary shaft assembly being rotatably coupled to said fixing shaft.

13. The automatic discharging device according to claim 12, wherein a locking bolt is provided on an outer end surface of the fixed shaft, and a gap is reserved between the locking bolt and the rotating shaft assembly.

14. The automatic discharging device according to claim 12, wherein said rotary shaft assembly comprises a rotary shaft, and a stop lever, a weight block and a top lever fixed on said rotary shaft, said rotary shaft being rotatably connected to said fixed shaft.

15. The automatic discharge device of claim 14, wherein said spoons have notches for said plungers to pass through.