CN110600145A - Locking, unlocking and grabbing lifting device for lead-based reactor fuel assembly - Google Patents

Locking, unlocking and grabbing lifting device for lead-based reactor fuel assembly Download PDF

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Publication number
CN110600145A
CN110600145A CN201910958005.8A CN201910958005A CN110600145A CN 110600145 A CN110600145 A CN 110600145A CN 201910958005 A CN201910958005 A CN 201910958005A CN 110600145 A CN110600145 A CN 110600145A
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CN
China
Prior art keywords
locking
self
claw
cylinder
sliding
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Granted
Application number
CN201910958005.8A
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Chinese (zh)
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CN110600145B (en
Inventor
盛鑫
顾龙
于锐
朱彦雷
刘璐
王大伟
李金阳
彭天骥
张璐
唐延泽
秦长平
范旭凯
田旺盛
姜韦
李秀凌
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Institute of Modern Physics of CAS
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Institute of Modern Physics of CAS
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Priority to CN201910958005.8A priority Critical patent/CN110600145B/en
Publication of CN110600145A publication Critical patent/CN110600145A/en
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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/30—Assemblies of a number of fuel elements in the form of a rigid unit
    • G21C3/32—Bundles of parallel pin-, rod-, or tube-shaped fuel elements
    • G21C3/33—Supporting or hanging of elements in the bundle; Means forming part of the bundle for inserting it into, or removing it from, the core; Means for coupling adjacent bundles
    • G21C3/331—Comprising hold-down means, e.g. springs
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/30—Assemblies of a number of fuel elements in the form of a rigid unit
    • G21C3/32—Bundles of parallel pin-, rod-, or tube-shaped fuel elements
    • G21C3/334—Assembling, maintenance or repair of the bundles
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/30—Assemblies of a number of fuel elements in the form of a rigid unit
    • G21C3/32—Bundles of parallel pin-, rod-, or tube-shaped fuel elements
    • G21C3/34—Spacer grids
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Load-Engaging Elements For Cranes (AREA)

Abstract

The invention relates to a locking, unlocking and grabbing lifting device for a lead-based reactor fuel assembly, which comprises a lower pipe seat buoyancy locking mechanism, an upper pipe seat self-locking mechanism and a refueling grabbing head mechanism, wherein the lower pipe seat buoyancy locking mechanism is connected with the upper pipe seat self-locking mechanism; the lower pipe seat buoyancy locking mechanism utilizes buoyancy to enable the floating slide cylinder to move upwards to push the ball anchor out of the lower pipe seat and embed the ball anchor into the locking groove of the reactor core grid plate, so that the ball anchor limits the mutual displacement of the lower pipe seat and the reactor core grid plate in a stop pin mode, and the lower pipe seat is locked on the reactor core grid plate; the upper pipe seat self-locking mechanism is used for preventing the ball anchor from being unlocked due to downward movement of the floating sliding cylinder; the refueling grabbing head mechanism is used for unlocking the buoyancy locking mechanism of the lower tube seat and the self-locking mechanism of the upper tube seat, and is also used for connecting the upper tube seat and lifting the fuel assembly. The three parts of the invention are mutually matched, so that the fuel assembly can be unlocked easily under the working condition of material lifting, lifted out of the core of the lead-based reactor, and locked on the grid plate of the core firmly under the working conditions of material loading and operation.

Description

Locking, unlocking and grabbing lifting device for lead-based reactor fuel assembly
Technical Field
The invention relates to a lead-based reactor assembly, in particular to a locking, unlocking and grabbing lifting device for a lead-based reactor fuel assembly.
Background
The lead-based reactor is a fast neutron reactor which takes molten lead or lead-bismuth alloy as a coolant, adopts closed fuel circulation and can operate under the conditions of normal pressure and high temperature. The lead-based reactor has excellent fuel conversion capacity, can effectively improve the utilization rate of uranium and thorium resources, improves the sustainability of the fuel, and can be used for incinerating long-life actinides in the conventional light water reactor spent fuel, thereby more cleanly utilizing nuclear energy. In addition, the inert and low pressure coolant system in the lead-based reactor further enhances the safety of the reactor.
The lead and lead bismuth alloy is characterized in that: lead and lead bismuth alloy are solid at normal temperature, the melting point of lead is 327.5 ℃, the melting point of lead bismuth alloy is 125 ℃, and the lead-based reactor coolant needs to melt and flow at high temperature; lead oxide of a solid substance is generated after the lead solution is contacted with air, and if the lead oxide flows along with liquid lead, equipment in a reactor can be damaged and blocked; the content of oxygen in the lead-bismuth alloy melt needs to be controlled to reduce corrosion to the metal materials in the reactor, and the bismuth element and the neutron in the lead-bismuth alloy melt react to generate trace amount of polonium (P-210). Therefore, the lead-based reactor must maintain high heat preservation and sealing, and an effective treatment and purification system is adopted to ensure the environment and personnel safety, so that the lead-based reactor needs an in-reactor refueling mode different from the traditional pressurized water reactor uncapping refueling mode. However, the fuel assemblies in the in-core refueling mode are not provided with an upper part pressing and fixing device, but are fixed on the grid plate of the reactor core by designing a locking mechanism, and when refueling, a refueling machine is needed to unlock the locking mechanism of the fuel assemblies and is fixedly connected with the upper end seats of the fuel assemblies, and then the fuel assemblies are lifted out of the reactor core.
As is well known, lead has a density of 11.34g/cm3The density of the lead-bismuth alloy is 10.5g/cm3The density of the steel material is 7.9g/cm3Since the average density of the fuel assembly made of steel material is lower than that of the lead-based coolant (for convenience of description, the lead melt and the lead-bismuth alloy melt are collectively referred to as the lead-based coolant), the fuel assembly is subjected to upward buoyancy when immersed in the lead-based coolant, and cannot be placed in the lead-based reactor. To address this problem, two approaches are generally used in existing fuel assembly designs: the first method is to add a counterweight made of tungsten or depleted uranium at the upper part or the lower part of the fuel assembly, the density of the two metals is higher than that of a lead-based coolant, so that the fuel assembly can be inserted into the holes of the grid plate of the reactor core against buoyancy, but the addition of the counterweight can influence the flow channel design inside the fuel assembly; the second is under the fuel assemblyAnd the locking mechanism is arranged on the pipe seat, and is started after the lower pipe seat is inserted into the hole of the reactor core grid plate, so that the fuel assembly is fixed on the reactor core grid plate. Because the fuel assembly is fixed on the reactor core grid plate by only depending on the locking mechanism, the buoyancy of the lead-based coolant can generate larger load on the locking mechanism, and the reliability of the locking mechanism is reduced, the balance weight and the locking mechanism are used simultaneously in the current domestic and foreign design, so that the fuel assembly is stably fixed on the reactor core grid plate. Since the locking mechanism of the fuel assembly is mostly a moving part, and the lead-based coolant environment is complex, the corrosion and erosion effects on the fuel assembly are large, and the moving part can be blocked by lead oxide and corrosion products. Therefore, the simplicity and reliability of the locking mechanism are very important, and a proper locking mechanism must be adopted to ensure that the fuel assemblies are effectively fixed on the reactor core grid plate under normal working conditions and other working conditions and realize flexible refueling.
Currently, the known design of fuel assemblies in lead-based reactors using locking mechanisms is the european union's XADS scheme. In the scheme, the lower pipe seat of the fuel assembly is internally provided with the reed type locking mechanism, a fuel rod at the center of the fuel assembly is drawn out, then a push rod is placed in the fuel rod, the upper part of the push rod is connected with the upper pipe seat transmission mechanism, and the lower part of the push rod is connected with the reed chuck in the lower pipe seat. The upper tube seat is under the action of the refueling machine grabbing head pushing mechanism, so that the push rod can move up and down, the push rod drives the reed clamping head to elastically deform and extend out of the lower tube seat outer sleeve of the fuel assembly, and then the reed clamping head is clamped with the lower surface of the reactor core grid plate, so that the fuel assembly is locked. However, the reed chuck of the reed type locking mechanism is thin and difficult to bear the long-term corrosion and erosion effects of the lead-based coolant, and meanwhile, under the high irradiation environment of the lead-based reactor, the material of the reed type locking mechanism can be subjected to irradiation embrittlement, so that the reed type locking mechanism is extremely easy to break, and the reliability of the scheme needs to be evaluated.
There are also known designs of fuel assemblies in lead-based reactors using locking mechanisms, and refill lifting solutions similar to automatic ball-point pens. Specifically, in a locking state, the locking mechanism is clamped in the circumferential tooth groove by virtue of self buoyancy; when unlocking is carried out, the lifting mechanism pushes the fuel assembly downwards, so that the locking sliding block slides to an unlocking position along the circumferential tooth groove, and therefore unlocking is achieved. Although the locking mechanism utilizes the characteristic of larger buoyancy of the liquid lead-bismuth alloy, the fuel assembly is not locked in the true sense, the fuel assembly still has the possibility of moving up and down, and particularly the fuel assembly is easy to move up and down under the earthquake working condition, so that the locking slide block slides to the unlocking position, and the fuel assembly is unlocked.
As described above, the conventional fuel assembly is difficult to withstand the combined effects of high temperature, high corrosion, high irradiation environment in the reactor and seismic load of the liquid lead-bismuth coolant in the lead-based reactor. Therefore, it is desirable to design and develop a locking, unlocking and gripping lifting device for a fuel assembly that is more reliable, easier to operate, and more fully utilizes the high buoyancy characteristics of liquid lead bismuth alloys.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a locking, unlocking, grabbing and lifting device for a lead-based reactor fuel assembly, which can easily realize the functions of locking, unlocking, grabbing and lifting the fuel assembly on a reactor core grid plate.
In order to achieve the purpose, the invention adopts the following technical scheme: a locking, unlocking, grabbing and lifting device for a lead-based reactor fuel assembly comprises a lower pipe seat buoyancy locking mechanism, an upper pipe seat self-locking mechanism and a refueling grabbing head mechanism;
wherein, lower tube socket buoyancy locking mechanism includes: the reactor core grid plate is provided with a through hole, and the inner wall of the hole of the reactor core grid plate is provided with a plurality of locking grooves along the circumferential direction; the lower pipe seat is a cylindrical shell, forms the outer boundary of the lower pipe seat buoyancy locking mechanism, and is used for being positioned and inserted into the hole of the reactor core grid plate, and a plurality of ball anchor holes are formed in the lower pipe seat along the circumferential direction in the region where the lower pipe seat is inserted into the reactor core grid plate; the floating sliding cylinder is a variable cross-section cylinder body, is coaxially arranged in the lower pipe seat and can vertically and axially move along with buoyancy, and a plurality of sections of sliding grooves are formed in the outer wall surface of the lower part of the floating sliding cylinder; the ball anchors are respectively limited between the ball anchor holes of the lower pipe seat and the multi-section sliding chutes of the floating sliding barrel and can only horizontally and axially move along the ball anchor holes of the lower pipe seat; the lower ends of the push rods are connected with the floating sliding cylinder;
upper tube seat self-locking mechanism includes: the upper tube seat is a cylindrical shell and forms the outer boundary of the upper tube seat self-locking mechanism; the self-locking claw boxes are arranged in the upper tube base; the hook claw ring is arranged in the upper pipe seat in a sliding manner, is connected with the upper end of the push rod and is used for being matched with the self-locking hook claw box to realize self-locking;
the first mechanism is grabbed in reloading includes: the lower end of the outward pushing cylinder can be in contact with the self-locking claw box and is used for pushing the self-locking claw box downwards to complete unlocking; the middle push cylinder is coaxially and slidably arranged in the outer push cylinder, and the lower end of the middle push cylinder can be in contact with the claw ring and is used for pushing the claw ring downwards; the locking hook claws are rotatably arranged on the middle push cylinder and are used for hooking the upper tube seat when the middle push cylinder moves downwards; the inner push cylinder is coaxially and slidably arranged in the middle push cylinder; and the roller boxes are arranged on the inner push cylinder, correspond to the locking hooks one by one and are used for driving the locking hooks to rotate when the inner push cylinder moves up and down.
Preferably, the locking, unlocking and grabbing lifting device is characterized in that a plurality of ball anchor holes are distributed along the circumferential direction of the lower tube seat at equal angular intervals, the diameter of each ball anchor hole is slightly larger than that of each ball anchor, the diameter of each ball anchor is about three times of the wall thickness of the lower tube seat, the outer edge of each ball anchor hole is an inward arc-shaped closing-up, and the radian of each arc-shaped closing-up is matched with the surface of each ball anchor, so that the ball anchors are prevented from falling out of the lower tube seat when moving horizontally and axially along the ball anchor holes;
meanwhile, a limiting boss is formed on the outer wall surface of the lower pipe seat, the diameter of the limiting boss is larger than that of the hole of the reactor core grid plate, and the limiting boss is used for limiting the downward insertion depth of the lower pipe seat.
Preferably, the inner cavity of the floating sliding cylinder is a through hole with equal diameter, the upper wall surface and the lower wall surface of the floating sliding cylinder are thicker, the middle wall surface is thinner, and the upper end surface of the floating sliding cylinder is provided with a plurality of threaded ports which are annularly arranged at equal angular intervals and are used for being connected with the lower end of the push rod;
the multi-section sliding groove is divided into 5 sections from top to bottom: the first section is a first vertical sliding groove, the second section is a slope sliding groove, the third section is a transition sliding groove, the fourth section is a second vertical sliding groove, the fifth section is a spherical groove, and the diameter of the spherical groove is equal to that of the ball anchor.
Locking, unblock and snatch hoisting device, preferably, a plurality of the auto-lock colludes the claw case and follows the hoop of upper tube seat is arranged at the equal angle interval, each the auto-lock colludes the claw case and includes: the hook claw box body is provided with a self-locking hook claw mounting groove on the inner side, and the lower part of the hook claw box body is provided with a first sliding groove; the self-locking hook claw is placed in a self-locking hook claw mounting groove of the hook claw box body, the upper end of the self-locking hook claw is rotatably connected with the hook claw box body through the self-locking hook claw pin shaft, and the lower end of the self-locking hook claw forms a hook head of the protruding hook claw box body; the lower base is used for tightly connecting the lower end of the hook claw box body and the upper end of the upper tube seat; the sliding block is arranged in a first sliding groove at the lower part of the hook claw box body in a sliding manner, and the inner side of the sliding block can be in contact with the self-locking hook claw and is used for blocking the self-locking hook claw from rotating outwards; and the elastic mechanism is connected between the lower base and the sliding block and is used for driving the sliding block to move up and down in the first sliding groove of the hook claw box body.
Preferably, the hook claw box body positioned at the outer side of the self-locking hook claw is provided with a stop pin for limiting the amplitude of outward rotation of the self-locking hook claw around the self-locking hook claw pin; the inner wall surface of the self-locking hook claw is provided with a bulge part protruding out of the hook claw box body, the position of the bulge part is lower than that of the self-locking hook claw pin shaft, and the self-locking hook claw can rotate around the self-locking hook claw pin shaft outwards when the bulge part is under the action of thrust.
Preferably, the left side, the right side and the outer side of the lower part of the hook claw box body are provided with the first sliding grooves, the left side, the right side and the outer side of the sliding block are provided with three side lugs, and the three side lugs of the sliding block are respectively arranged in the three first sliding grooves of the hook claw box body in a sliding manner; the upper end of a self-locking hook mounting groove of the hook claw box body is provided with a step surface, the upper end of the self-locking hook claw is provided with a boss, and the boss is matched with the step surface to limit the self-locking hook claw to rotate inwards around a self-locking hook claw pin shaft; meanwhile, an inner slope surface inclined from outside to inside is formed at the upper part of the inner side of the sliding block, and a vertical inner plane is formed at the lower part of the inner side of the sliding block.
Locking, unblock and snatch hoisting device, preferably, elastic mechanism includes: the lower end of at least one guide pin is fixedly connected to the lower base, and the upper end of the guide pin penetrates through the side lug of the sliding block and is fixedly connected with the claw box body; and the spring is sleeved on the guide pin between the lower base and the side lug of the sliding block.
Preferably, the inner wall surface of the upper part of the upper pipe seat is provided with a plurality of circumferential hook grooves which are distributed at equal angle intervals and are used for connecting the material changing and grabbing head mechanism; the middle part of the upper tube seat is provided with a plurality of self-locking claw box mounting grooves which are annularly arranged at equal angle intervals and used for mounting the self-locking claw boxes; the lower end surface of the hook claw ring is provided with threaded holes which are annularly arranged at equal angular intervals and are used for being in threaded connection with the upper end of the push rod;
and simultaneously, the lower end face of the hook head of the self-locking hook claw is in arc transition, and the outer edge of the upper end face of the hook claw ring is in arc transition and is used for pushing the lower end face of the hook head of the self-locking hook claw outwards when the self-locking hook claw moves upwards.
Preferably, a guide support ring is formed on the inner wall surface of the lower tube seat, and the inner wall surface of the guide support ring is in contact with the outer wall surface of the upper part of the floating sliding cylinder to form a sliding pair so as to radially support the floating sliding cylinder;
the lower baffle ring is also formed on the inner wall surface of the lower tube seat positioned below the floating sliding cylinder and used for limiting the vertical downward movement distance of the floating sliding cylinder;
meanwhile, a push rod supporting ring is formed on the inner wall surface of the upper tube seat above the floating sliding cylinder, a guide hole with a diameter slightly larger than that of the push rod is formed in the push rod supporting ring, and the push rod penetrates through the guide hole to radially support the push rod.
Locking, unblock and snatch hoisting device, preferred, its characterized in that a plurality of gyro wheel case mounting groove that the annular equiangular interval was arranged is opened to the lower part of interior pushing cylinder, each the gyro wheel case includes: the roller box body is arranged in the roller box mounting groove of the inner push cylinder; the roller is rotatably arranged in the roller box body through the roller pin shaft, and the outer side part of the roller protrudes out of the roller box body and is in contact with the inner wall surface of the locking claw;
meanwhile, a plurality of locking claw mounting grooves which are circumferentially arranged at equal angle intervals are formed in the middle of the middle push cylinder, and the locking claws are rotatably connected in the locking claw mounting grooves through locking claw pin shafts; the lower part of the locking claw forms a hook head protruding outwards, and the hook head is used for being inserted into a hook groove of the upper tube seat; the upper end of the inner wall surface of the locking hook claw is an inclined inward cambered surface, and the lower end of the inner wall surface is a vertical plane.
Preferably, the lower end surface of the outer pushing cylinder is provided with notches matched with the three side lugs of the sliding block, so that the side lugs of the sliding block can be conveniently pushed; an annular boss is formed on the inner wall surface of the outer pushing cylinder, and the annular boss is in contact with the outer wall surface of the middle pushing cylinder and used for forming radial support for the middle pushing cylinder; a plurality of second sliding grooves which are circumferentially arranged at equal angle intervals are formed in the outer pushing cylinder above the annular boss, first sliding pins are placed in the second sliding grooves, the outer ends of the first sliding pins are arranged in the second sliding grooves in a sliding mode, and the inner ends of the first sliding pins are fixedly connected with the middle pushing cylinder, so that the mutual rotation and axial movement distance between the outer pushing cylinder and the middle pushing cylinder are limited;
simultaneously, a plurality of third spout that the annular was arranged to the equiangular interval is opened on the upper portion of well pushing cylinder, place in the third spout second slip pin, the outer end of second slip pin slides and sets up in the third spout, the inner of second slip pin with interior pushing cylinder fastening connection, restriction from this mutual rotation and the axial displacement distance between well pushing cylinder and the interior pushing cylinder.
Due to the adoption of the technical scheme, the invention has the following advantages: 1. the invention fully utilizes the characteristic of high density of the liquid lead-bismuth alloy, and the fuel assembly is firmly locked on the reactor core grid plate by utilizing buoyancy and the buoyancy locking mechanism of the lower pipe seat and the self-locking mechanism of the upper pipe seat, so that the invention is safer and more reliable than the circumferential tooth groove structure in the prior art. 2. The lower pipe seat buoyancy locking mechanism adopts a ball anchor buoyancy locking method, the ball anchor is pushed by a plurality of sections of chutes of the floating sliding barrel through buoyancy and is pushed out through a lower pipe seat through hole to be clamped into a locking groove of a reactor core grid plate, and therefore the ball anchor is positioned among the reactor core grid plate, the lower pipe seat and the floating sliding barrel in a stop pin mode and is limited from moving mutually; meanwhile, the floating slide cylinder adopts the design of a plurality of sections of slide grooves, and can be used for preventing the ball anchor from being contracted into the ball anchor hole of the lower tube seat after being extruded by the wall surface of the hole of the grid plate of the reactor core. Compared with the traditional spring leaf type locking mechanism utilizing elastic deformation, the lower pipe seat buoyancy locking mechanism can effectively avoid locking failure caused by corrosion, erosion and irradiation embrittlement of structural materials. 3. The self-locking hook claw box with the self-locking function is arranged in the self-locking mechanism of the upper tube seat, and the hook claw ring is restrained to move downwards through the self-locking hook claw, so that the downward movement of the floating sliding cylinder is limited, the position of the floating sliding cylinder is fixed, the restraining state of the ball anchor is kept, and the ball anchor cannot be unlocked under the earthquake working condition, so that the safety guarantee of the buoyancy locking of the ball anchor is realized. Compared with a common refill buoyancy lifting locking method similar to an automatic ball-point pen, the upper tube seat self-locking mechanism effectively avoids the problem that the fuel assembly is unlocked due to the fact that the buoyancy locking device floats under earthquake load. 4. The fuel assembly loading and unloading of the invention adopts the same refueling grapple mechanism, the refueling grapple mechanism only needs three-section axial movement to complete the locking or unlocking of the lower tube seat and the reactor core grid plate, the locking or unlocking of the self-locking grapple box and the separation or connection of the locking grapple and the upper tube seat, and the refueling grapple mechanism has simple structure and strong reliability compared with the moving and rotating unlocking scheme of the prior refueling grapple.
Drawings
FIG. 1 is an overall cross-sectional view of the present invention;
FIG. 2 is a cross-sectional view of the lower seat buoyancy lock mechanism of the present invention;
FIG. 3 is a schematic view of the constraint relationship between the ball anchor and the ball anchor hole of the present invention;
FIG. 4 is an isometric view of a floating slide of the present invention;
FIG. 5 is a cross-sectional view of the floating slide of the present invention;
FIG. 6 is a state view of the downcomer locking mechanism when the fuel assembly is not installed in the lead-based reactor core;
FIG. 7 is a state diagram of the lower tube support buoyancy locking mechanism during insertion of a fuel assembly into a lead-based reactor core;
FIG. 8 is a state diagram of the lower tube seat buoyancy lock mechanism after the fuel assembly is placed in the lead-based reactor core;
FIG. 9 is a state diagram of the buoyancy locking mechanism of the lower nozzle when the lower nozzle is locked on the grid plate of the reactor core according to the present invention;
FIG. 10 is a cross-sectional view of the top nozzle self-locking mechanism of the present invention;
FIG. 11 is an isometric view of the self-locking pawl magazine of the present invention;
FIG. 12 is a cross-sectional view of the self-locking pawl cage of the present invention;
FIG. 13 is a schematic structural view of a slider, a resilient mechanism and a lower base according to the present invention;
FIG. 14 is an isometric view of a slide of the present invention;
FIG. 15 is a state view of the top nozzle self-locking mechanism when the fuel assembly is not inserted into the lead-based reactor core;
FIG. 16 is a state diagram of the upper nozzle self-locking mechanism during the process of placing the fuel assembly into the core of the lead-based reactor;
FIG. 17 is a state view of the top nozzle self-locking mechanism after the fuel assembly has been placed in the lead based reactor core;
FIG. 18 is a state view of the upper nozzle self-locking mechanism of the present invention with the lower nozzle locked to the grid plate of the core;
FIG. 19 is a half-sectional isometric view of the change gripper mechanism of the present invention;
FIG. 20 is a cross-sectional view of the refueling grapple mechanism of the present invention;
FIG. 21 is a state diagram of the present invention before material lifting;
FIG. 22 is a state diagram of the present invention during the first stage of the material lifting;
FIG. 23 is a state diagram of the present invention during the second stage of the material withdrawal;
FIG. 24 is a state diagram of the present invention during the third step of the material extraction;
FIG. 25 is a state diagram of the present invention during the fourth step of lifting;
FIG. 26 is a state of the invention prior to charging;
FIG. 27 is a state diagram of the present invention during a first step of charging;
FIG. 28 is a state diagram of the present invention during a second step of charging;
FIG. 29 is a state diagram of the present invention during the third step of loading;
FIG. 30 is a state diagram of the present invention during the fourth step of charging.
Detailed Description
The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the invention can be more clearly understood. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely intended to illustrate the spirit of the technical solution of the present invention.
Fig. 1 shows a locking, unlocking and grabbing lifting device for a lead-based reactor fuel assembly provided by the invention, which comprises a fuel assembly mainly composed of a lower pipe seat buoyancy locking mechanism 100 and an upper pipe seat self-locking mechanism 200, and a refueling grabbing head mechanism 300.
As shown in fig. 2, the lower pipe support buoyancy locking mechanism 100 includes: the reactor core grid plate 5 is characterized in that a through hole is formed in the reactor core grid plate 5, and a plurality of locking grooves are formed in the inner wall of the hole of the reactor core grid plate 5 along the circumferential direction; the lower pipe seat 2 is a cylindrical shell and forms the outer boundary of the lower pipe seat buoyancy locking mechanism 100 and is used for being positioned and inserted into the hole of the reactor core grid plate 5, and a plurality of ball anchor holes are formed in the lower pipe seat 2 along the circumferential direction in the region where the reactor core grid plate 5 is inserted; the floating sliding cylinder 7 is a variable cross-section cylinder body, is coaxially arranged in the lower pipe seat 2 and can vertically and axially move along with buoyancy, and a plurality of sections of sliding grooves are formed on the outer wall surface of the lower part of the floating sliding cylinder 7; the ball anchors 6 are respectively limited between the ball anchor holes of the lower pipe seat 2 and the multi-section sliding chutes of the floating sliding barrel 7, and can only move along the ball anchor holes of the lower pipe seat 2 in the horizontal axial direction; the lower ends of the push rods 1 and the push rods 1 are connected with a floating sliding cylinder 7. Thus, the lower nozzle buoyancy locking mechanism 100 moves the floating slide 7 upward by buoyancy to push the ball anchor 6 out of the ball anchor hole of the lower nozzle 2 and fit into the locking groove of the grid plate 5, so that the ball anchor 6 restricts the mutual displacement of the lower nozzle 2 and the grid plate 5 by a stopper pin, thereby locking the lower nozzle 2 to the grid plate 5.
In the above embodiment, preferably, as shown in fig. 2 and 3, the plurality of ball anchor holes are arranged at equal angular intervals along the circumferential direction of the lower socket 2, the diameter of each ball anchor hole is slightly larger than the diameter of the ball anchor 6, the diameter of the ball anchor 6 is about three times of the wall thickness of the lower socket 2, the outer edge of each ball anchor hole is an inward arc-shaped closed opening, and the radian of the arc-shaped closed opening is matched with the surface of the ball anchor 6, so that the ball anchor 6 can be prevented from falling out of the lower socket 2 when moving along the horizontal axial direction of the ball anchor hole; meanwhile, a limiting boss is formed on the outer wall surface of the lower tube seat 2, and the diameter of the limiting boss is larger than that of the hole of the reactor core grid plate 5 and used for limiting the downward insertion depth of the lower tube seat 2.
In the above embodiment, preferably, as shown in fig. 4 and 5, the inner cavity of the floating sliding cylinder 7 is a through hole with equal diameter, the upper and lower wall surfaces of the floating sliding cylinder 7 are thicker, the middle wall surface is thinner, and the upper end surface of the floating sliding cylinder 7 is provided with a plurality of threaded ports arranged circumferentially at equal angular intervals for connecting with the lower end of the push rod 1; the multi-section sliding groove is divided into 5 sections from top to bottom: the first section is a first vertical sliding groove I, the second section is a slope sliding groove II, the third section is a transition sliding groove III, the fourth section is a second vertical sliding groove IV, the fifth section is a spherical groove V, and the diameter of the spherical groove V is equal to that of the ball anchor 6.
In the above embodiment, as shown in fig. 1 and 2, preferably, the guide support ring 3 is formed on the inner wall surface of the bottom nozzle 2, and the inner wall surface of the guide support ring 3 contacts with the upper outer wall surface of the floating slide cylinder 7 to form a sliding pair so as to radially support the floating slide cylinder 7; meanwhile, a lower retainer ring 4 is formed on the inner wall surface of the lower tube base 2 below the floating slide cylinder 7 for limiting the vertical downward movement distance of the floating slide cylinder 7.
When the buoyancy locking mechanism 100 is used, the buoyancy locking process of the lower pipe seat buoyancy locking mechanism 100 is as follows:
when the fuel assembly is not placed in the lead-based reactor core, the floating sliding barrel 7 moves downwards to the upper surface of the lower retaining ring 4 under the action of gravity, then an axial downward thrust is transmitted through the refueling grabbing head mechanism 300, and then is transmitted to the floating sliding barrel 7 through the push rod 1, so that the floating sliding barrel 7 is pressed on the lower retaining ring 4, and the thrust is greater than the buoyancy of the floating sliding barrel 7 and the push rod 1 in the lead-based coolant. At this time, the ball anchor 6 is located in a space formed by the first vertical sliding groove i of the floating sliding cylinder 7 and the ball anchor hole of the lower socket 2, and the space can make the ball anchor 6 shrink in the ball anchor hole of the lower socket 2, so that the ball anchor 6 does not bear any external load (the state is shown in fig. 6).
When the fuel assembly is inserted into the lead-based reactor core, the fuel assembly can be sunk into the lead-based coolant due to the counterweight inside the fuel assembly, and the floating slide 7 cannot float upwards due to the previously applied downward thrust. After the lower pipe seat 2 is inserted into the hole of the reactor core grid plate 5 to a certain depth, the limiting boss outside the lower pipe seat 2 is clamped on the upper surface of the hole of the reactor core grid plate 5 to prevent the lower pipe seat 2 from continuously sinking, and meanwhile, the ball anchor 6 corresponds to the locking groove position on the reactor core grid plate 5. At this time, the thrust is removed from the material changing gripper mechanism 300, the floating slide cylinder 7 starts to float upwards under the buoyancy action of the lead-based coolant, when the ball anchor 6 contacts the slope slide groove ii of the multi-section slide groove, the slope slide groove ii gradually applies an outward thrust to the ball anchor 6, and the ball anchor 6 gradually starts to be pushed out of the ball anchor hole from the state of being retracted into the ball anchor hole (the state is shown in fig. 7). When the transition chute iii of the multi-stage chute slides smoothly over the ball anchor 6, the ball anchor 6 contacts the second vertical chute iv of the multi-stage chute, and at this time, the outer portion of the ball anchor 6 is pushed out of the ball anchor hole and is fitted into the locking groove of the grid plate 5 of the core (this state is shown in fig. 8).
The floating sliding cylinder 7 continues to float upwards, and when the ball anchor 6 is in contact with the spherical surface groove V of the multi-section sliding groove, the ball anchor 6 blocks the floating sliding cylinder 7 so that the floating sliding cylinder is not floated upwards any more. At this time, the ball anchor 6 penetrates the ball anchor hole of the lower socket 2, and is circumferentially constrained by the wall surface of the ball anchor hole, and if the ball anchor 6 moves outward in the axial direction of the ball anchor hole, it is hindered by the arc-shaped closing-up of the outer edge of the ball anchor hole. When the ball anchor 6 is extruded by the wall surface of the locking groove on the grid plate 5 of the reactor core, the ball anchor 6 can axially retract along the ball anchor hole of the lower tube seat 2, a vertical extrusion force acts on the second vertical chute IV of the multi-section chute, and the floating slide cylinder 7 cannot generate any upward or downward thrust, and due to the constraint action of the guide support ring 3, the floating slide cylinder 7 cannot move in the radial direction, so that the axial retraction of the ball anchor 6 along the ball anchor hole is also constrained. Under the action of buoyancy, the spherical grooves v of the multi-segment chute always keep applying an upward thrust to the lower surface of the ball anchor 6, so that the position of the ball anchor 6 is locked by the buoyancy, and the ball anchor 6 at the position is positioned among the hole of the grid plate 5 of the core, the ball anchor hole of the lower tube base 2 and the floating slide 7, and the mutual movement between the grid plate 5 of the core and the lower tube base 2 is limited in the form of a stop pin, so that the lower tube base 2 is locked on the grid plate 5 of the core by the buoyancy (this state is shown in fig. 9).
As described above, to ensure the locking of the lower nozzle 2 to the grid plate 5, the floating slide 7 is pressed upward against the ball anchor 6 by the buoyancy to limit the displacement of the ball anchor 6 and keep the position of the floating slide 7 constant. Under normal working conditions, the floating slide cylinder 7 only bears buoyancy and can keep the position unchanged. However, under the working condition of an earthquake, the floating sliding barrel 7 may float downwards due to the shaking of the lead-based coolant, so that the inner side of the ball anchor 6 is not restrained, and the fuel assembly is unlocked, and therefore the upper pipe base self-locking mechanism 200 is designed for limiting the problem that the floating sliding barrel 7 floats downwards under the working condition of the earthquake.
As shown in fig. 10, the top mount self-locking mechanism 200 includes: an upper tube seat 8 which is a cylindrical shell and forms the outer boundary of the upper tube seat self-locking mechanism 200; the self-locking claw boxes 9 are arranged in the upper tube base 8; the hook claw ring 11 is arranged in the upper tube seat 8 in a sliding mode, connected with the upper end of the push rod 1 and used for being matched with the self-locking hook claw box 9 to achieve self-locking.
In the above embodiment, preferably, as shown in fig. 11 and 12, a plurality of self-locking hooking claw boxes 9 are arranged at equal angular intervals along the circumferential direction of the upper pipe seat 8, and each self-locking hooking claw box 9 includes: the inner side of the claw hooking box body 91 is provided with a self-locking claw hooking installation groove, and the lower part of the claw hooking box body 91 is provided with a first sliding groove; the self-locking hook claw 93 is placed in a self-locking hook claw mounting groove of the hook claw box body 91, the upper end of the self-locking hook claw 93 is rotatably connected with the hook claw box body 91 through a self-locking hook claw pin shaft 92, and the lower end of the self-locking hook claw 93 forms a hook head protruding out of the hook claw box body 91; the lower base 94 is used for tightly connecting the lower end of the claw box 91 and the upper end of the upper pipe seat 8; the sliding block 96 is arranged in the first sliding groove at the lower part of the hook claw box body 91 in a sliding manner, and the inner side of the sliding block can be in contact with the self-locking hook claw 93 and is used for preventing the self-locking hook claw 93 from rotating outwards; and the elastic mechanism 95 is connected between the lower base 94 and the sliding block 96 and used for driving the sliding block 96 to move up and down in the first sliding groove of the claw box 91.
In the above embodiment, preferably, the hook box 91 located outside the self-locking hook 93 is provided with a stop pin 97, when the self-locking hook 93 rotates outwards around the self-locking hook pin 92, due to buoyancy, a turning moment is given to the self-locking hook 93, so that the self-locking hook 93 rotates at a large angle and collides with the inner wall surface of the hook box 91, and the position of the stop pin 97 can be limited to the extent that the self-locking hook 93 rotates outwards, and at the same time, the self-locking hook 93 is located at an appropriate angle at which the slider 96 pushes upwards. The inner wall surface of the self-locking hook claw 93 is provided with a bulge part protruding out of the hook claw box body 91, the position of the bulge part is lower than that of the self-locking hook claw pin shaft 92, and when a thrust is acted on the bulge part, the self-locking hook claw 93 can rotate outwards around the self-locking hook claw pin shaft 92.
As shown in fig. 11 to 14, the left, right and outer sides of the lower portion of the hook box 91 are both provided with first sliding grooves, the left, right and outer sides of the slider 96 are provided with three side lugs 961, the three side lugs 961 of the slider 96 are respectively slidably disposed in the three first sliding grooves of the hook box 91, and the three side lugs 961 are used for bearing external loads and enabling stress to be uniform, so that the slider 96 is prevented from being locked due to uneven stress. The upper end of a self-locking hook mounting groove of the hook claw box body 91 is provided with a step surface, the upper end of the self-locking hook claw 93 is provided with a boss, and the boss is matched with the step surface to limit the self-locking hook claw 93 to rotate inwards around a self-locking hook claw pin shaft 92; meanwhile, the upper part of the inner side of the sliding block 96 forms an inner slope 962 inclined from outside to inside, and the lower part of the inner side of the sliding block 96 forms a vertical inner plane 963.
In the above embodiment, preferably, the elastic mechanism 95 includes: the lower end of at least one guide pin 952 is fixedly connected to the lower base 94, and the upper end of the guide pin 952 penetrates through the side lug 961 of the sliding block 96 and then is fixedly connected with the claw box 91; a spring 951 is mounted around a guide pin 952 between the lower base 94 and the side ears 961 of the slider 96. The guide pin 952 is used for restricting the movement of the slide block 96, so that the slide block 96 can only slide up and down along the axial direction of the guide pin 952 under the action of external force; meanwhile, the spring 951 is positioned and restrained, so that the spring 951 is bent and deformed along the axial direction of the guide pin 952, and the spring 951 is used for pushing the sliding block 96 upwards to a self-locking position through restoring force of the spring 951 after external force borne on the sliding block 96 is removed. Because the slide block 96 is simultaneously subjected to the upward restoring force of the spring 951 and the buoyancy of the lead-based coolant, the slide block 96 is difficult to move downwards even under the earthquake working condition, and the slide block 96 always keeps the position state of the self-locking hook claw 93, so that the self-locking hook claw box 9 can keep the downward movement constraint on the floating slide cylinder 7.
Meanwhile, as shown in fig. 10, a pushrod supporting ring 10 is formed on an inner wall surface of the upper pipe support 8 located above the floating slide cylinder 7, a guide hole having a diameter slightly larger than that of the pushrod 1 is opened in the pushrod supporting ring 10, and the pushrod 1 penetrates through the guide hole to radially support the pushrod 1.
In the above embodiment, preferably, a plurality of circumferential hook grooves arranged at equal angular intervals are formed on the inner wall surface of the upper part of the upper pipe seat 8, and are used for connecting the material changing gripper head mechanism 300; and a plurality of self-locking claw box mounting grooves which are annularly arranged at equal angle intervals are formed in the middle of the upper tube seat 8 and are used for mounting the self-locking claw box 9. The lower end surface of the claw ring 11 is provided with threaded holes which are annularly arranged at equal angular intervals and are used for being in threaded connection with the upper end of the push rod 1. Meanwhile, the lower end face of the hook head of the self-locking hook 93 is in arc transition, and the outer edge of the upper end face of the hook ring 11 is in arc transition, so that the lower end face of the hook head of the self-locking hook 93 is pushed outwards when the self-locking hook moves upwards.
When the buoyancy self-locking device is used, the buoyancy self-locking process of the upper pipe seat self-locking mechanism 200 is as follows:
when the fuel assembly is not put into the core of the lead-based reactor, the movable part consisting of the hook ring 11, the push rod 1 and the floating slide cylinder 7 moves downwards under the action of gravity, and a downward thrust F is given to the hook ring 11 through the refueling grabbing head mechanism 3001Then, the floating slide cylinder 7 is pressed on the lower baffle ring 4 through the push rod 1; at the same time, the material changing gripper head mechanism 300 also gives a downward thrust F to the side lug 961 of the slide block 96 in the self-locking claw box 92The slider 96 is moved down along the guide pin 952 and compresses the spring 951, so that the slider 96 does not restrain the self-locking hook 93 (this state is shown in fig. 15).
After the fuel assembly is inserted into the reactor core grid plate hole 5, the thrust F of the refueling grabbing head mechanism 300 acting on the hook ring 11 is removed1The hook claw ring 11, the push rod 1 and the floating sliding cylinder 7 start to move upwards under the action of buoyancy. The upper end arc surface of the hook claw ring 11 can push the self-locking hook claw 93 to rotate outwards around the self-locking hook claw pin shaft 92 after contacting the hook head lower end arc surface of the self-locking hook claw 93. At the same time, the ball anchor 6 is pushed out gradually laterally in the upward movement of the floating slide 7 (this state is shown in fig. 16).
The movable part composed of the claw ring 11, the push rod 1 and the floating sliding cylinder 7 continuously moves upwards under the action of buoyancy, when the ball anchor 6 contacts with the spherical groove V on the floating sliding cylinder 7, the floating sliding cylinder 7 is clamped by the ball anchor 6, and the movable part stops moving upwardsAnd the lower pipe base 2 completes buoyancy locking. At this time, the hook claw ring 11 is just located at the upper end of the hook head of the self-locking hook claw 93, but the downward movement of the floating slide cylinder 7 is not restricted. After the lower pipe seat 2 is locked, the downward pushing force F of the material changing grabbing head mechanism 300 acting on the side lug 961 of the sliding block 96 is removed2At this time, the slider 96 starts to move upward along the guide pin 952 by the restoring force of the spring 951 and the buoyancy of the lead-based coolant (this state is shown in fig. 17).
When the inner slope 962 of the upwardly moving slide block 96 contacts with the lower end surface of the hook head of the self-locking hook claw 93, the self-locking hook claw 93 is pushed to rotate inwards around the self-locking hook claw pin shaft 92, and as the slide block 96 continues to move upwards to reach the maximum stroke, the inner plane 963 of the slide block 96 is in parallel contact with the outer plane of the self-locking hook claw 93, and at the moment, the slide block 96 abuts against the self-locking hook claw 93 to limit the self-locking hook claw 93 to rotate outwards around the self-locking hook claw pin shaft 92; meanwhile, an upper end boss of the self-locking hook claw 93 is also in contact with an upper end step surface of a self-locking hook claw mounting groove of the hook claw box shell 91 to limit the self-locking hook claw to rotate inwards around the self-locking hook claw pin shaft 92, so that the self-locking hook claw 93 is locked in position. At this time, the hook head of the self-locking hook 93 is located on the lower surface of the hook ring 11, and the downward movement of the hook ring 11 is limited, because the hook ring 11 and the floating slide cylinder 7 are connected together through the push rod 1, the downward movement of the floating slide cylinder 7 is also limited, and when the lower tube seat 2 is locked by buoyancy, the ball anchor 6 already limits the floating slide cylinder 7 to move upward, and the floating slide cylinder 7 is also completely limited from this (this state is shown in fig. 18).
The fuel assembly of the invention needs the refueling grapple mechanism 300 to realize the locking and unlocking of the lower pipe seat buoyancy locking mechanism 100 and the upper pipe seat self-locking mechanism 200 in the refueling process. As shown in fig. 19 and 20, the material changing gripper head mechanism 300 includes: the lower end of the outer push cylinder 17 can be in contact with a sliding block 96 of the self-locking claw box 9 and is used for pushing the sliding block 96 downwards to complete unlocking of the self-locking claw box 9; the middle push cylinder 18 is coaxially and slidably arranged in the outer push cylinder 17, and the lower end of the middle push cylinder 18 can be in contact with the claw ring 11 and is used for pushing the claw ring 11 downwards; the locking hook claws 15 are rotationally arranged on the middle push cylinder 18 and are used for hooking the upper tube seat 8 when the middle push cylinder 18 moves downwards; the inner push cylinder 12 is coaxially and slidably arranged in the middle push cylinder 18; the roller boxes 16 and a plurality of roller boxes 16 are arranged on the inner push cylinder 12 and correspond to the locking hooks 15 one by one, and are used for driving the locking hooks 15 to rotate when the inner push cylinder 12 moves up and down.
In the above embodiment, preferably, a plurality of roller box installation slots are formed at the lower portion of the inner pushing cylinder 12 and arranged circumferentially at equal angular intervals, and each roller box 16 includes: a roller box body 163 installed in the roller box installation groove of the inner push cylinder 12; the roller 161 is rotatably disposed in the roller case 163 by the roller pin 162, and an outer portion of the roller 161 protrudes from the roller case 163 and contacts an inner wall surface of the locking claw 15. Meanwhile, a plurality of locking claw mounting grooves which are annularly arranged at equal angle intervals are formed in the middle of the middle push barrel 18, and the locking claw 15 is rotatably connected in the locking claw mounting grooves through a locking claw pin shaft 14. The lower part of the locking claw 15 forms a hook head protruding outwards, and the hook head is used for being inserted into a hook groove of the upper tube seat 8; the internal face upper end that the claw 15 is colluded in the locking is the inward cambered surface of slope, and the internal face lower extreme is vertical plane, reciprocates the cambered surface that the claw 15 is colluded in the contact locking and plane promotion locking through gyro wheel 161 from this and colludes the claw 15 rotation in order to realize receiving the claw and stretching the function of claw: when the inner pushing cylinder 12 moves downwards, the roller 161 contacts the lower end plane of the inner wall surface of the locking claw 15, and pushes the locking claw 15 to rotate outwards around the locking claw pin shaft 14, so that the claw extending function is realized; when the inner pushing cylinder 12 moves upwards, the roller 161 contacts the upper end arc surface of the inner wall surface of the locking claw 15, and pushes the locking claw 15 to rotate inwards around the locking claw pin shaft 14, so that the claw folding function is realized. In addition, a claw roller 151 is rotatably connected to the upper portion of the locking claw 15 through a claw roller pin 152, the claw roller 151 contacts with the outer wall surface of the inner push cylinder 12 when the locking claw 15 extends, and the roller 161 of the roller box 16 contacts with the lower end surface of the inner wall surface of the locking claw 15, so that the roller 161 and the claw roller 151 jointly limit the rotation of the locking claw 15 to keep the locking claw 15 at a fixed position.
In the above embodiment, preferably, the lower end surface of the outward pushing cylinder 17 is provided with notches matched with the three side lugs 961 of the sliding block 96, so as to facilitate pushing the side lugs 961 of the sliding block 96; an annular boss is formed on the inner wall surface of the outer push cylinder 17, and the annular boss is in contact with the outer wall surface of the middle push cylinder 18 and is used for forming radial support for the middle push cylinder 18; a plurality of second sliding grooves which are annularly arranged at equal angle intervals are formed in the outer pushing cylinder 17 above the annular boss, a first sliding pin 13 is placed in each second sliding groove, the outer end of the first sliding pin 13 is arranged in each second sliding groove in a sliding mode, the inner end of the first sliding pin 13 is fixedly connected with the middle pushing cylinder 18, and therefore mutual rotation and axial movement distance between the outer pushing cylinder 17 and the middle pushing cylinder 18 are limited. Meanwhile, the upper part of the middle push cylinder 18 is provided with a plurality of third sliding grooves which are annularly arranged at equal angle intervals, second sliding pins 19 are placed in the third sliding grooves, the outer ends of the second sliding pins 19 are slidably arranged in the third sliding grooves, and the inner ends of the second sliding pins 19 are fixedly connected with the inner push cylinder 12, so that the mutual rotation and axial movement distance between the middle push cylinder 18 and the inner push cylinder 12 are limited.
Therefore, the lower pipe support buoyancy locking mechanism 100, the upper pipe support self-locking mechanism 200 and the refueling grabbing head mechanism 300 are matched with one another, so that the fuel assembly can be unlocked easily under the material lifting working condition, lifted out of the lead-based reactor core, and firmly locked on the reactor core grid plate 5 under the material loading and operating working conditions.
The functions of the lower tube seat buoyancy locking mechanism 100, the upper tube seat self-locking mechanism 200 and the refueling grabbing head mechanism 300 which are matched with each other to lock, unlock and grab the lifting assembly are respectively described below by two embodiments of lifting out spent fuel assemblies and loading new fuel assemblies into stacks.
The first embodiment is as follows:
when the spent fuel assemblies are lifted, the spent fuel assemblies are unlocked from the core grid plate 5 and the lead-based reactor core is lifted (the state before lifting is shown in fig. 21), and the steps comprise:
firstly, the refueling grab head mechanism 300 moves above the upper pipe seat self-locking mechanism 200, an outer push barrel 17 of the refueling grab head mechanism 300 moves downwards to contact with a side lug 961 of a slide block 96 in a hook claw box 91, so that the refueling grab head mechanism overcomes the resistance of a spring 951 and the buoyancy of a lead-based coolant and moves downwards along a guide pin 952, and the constraint that the slide block 96 rotates a self-locking hook claw 93 outwards around a self-locking hook claw pin shaft 92 is removed (the state is shown in fig. 22);
secondly, the middle push cylinder 18 of the material changing gripper head mechanism 300 moves downwards, firstly, the outer edge of the lower end of the middle push cylinder 18 pushes a convex part on the inner wall surface of the self-locking hook claw 93, so that the self-locking hook claw 93 rotates outwards around the self-locking hook claw pin shaft 92, and the blocking effect of the self-locking hook claw 93 on the lower end surface of the hook claw ring 11 is removed; then, the middle push cylinder 18 overcomes buoyancy to push the claw ring 11 downwards, and the floating slide cylinder 7 is pressed on the lower retaining ring 4 through the connection of the push rod 1; at this time, the locking hook claw 15 on the middle push tube 18 corresponds to the hook groove position of the inner wall surface of the upper end of the upper tube seat 8, and the locking between the ball anchor 6 and the reactor core grid plate 5 is released (this state is shown in fig. 23);
thirdly, the inner push tube 12 of the material changing gripper mechanism 300 moves downwards, when the roller 161 of the roller box 16 moves to the lower end plane of the inner wall surface of the locking claw 15, the locking claw 15 is pushed to rotate outwards around the locking claw pin shaft 14, and the hook head of the locking claw 15 is inserted into the hook groove of the inner wall surface of the upper end of the upper tube base 8, thereby completing the fixed connection between the material changing gripper mechanism 300 and the upper tube base self-locking mechanism 200 (the state is shown in fig. 24);
fourth, the spent fuel assembly is lifted out of the lead-based reactor core by lifting the refueling machine gripper mechanism 300 (this state is shown in fig. 25).
Example two:
when loading, new fuel assemblies need to be placed in the lead-based reactor core, the refueling grabbing head mechanism 300 needs to be connected with the upper tube seat self-locking mechanism 200 during loading, and the refueling grabbing head mechanism 300 drives the new fuel assemblies to move downwards to the reactor core grid plate 5 (the state is shown in fig. 26), and the steps of the refueling grabbing head mechanism include:
firstly, inserting a lower pipe seat 2 into a hole of a reactor core grid plate 5, and after a limiting boss outside the lower pipe seat 2 is contacted with the reactor core grid plate 5, the whole new fuel assembly moves vertically and downwards to be restrained and stops sinking (the state is shown in fig. 27);
secondly, moving the inner push cylinder 12 of the material changing gripper head mechanism 300 upwards, moving the roller 161 of the roller box 16 to the arc surface at the upper end of the inner wall surface of the locking claw 15, so that the locking claw 15 rotates inwards around the locking claw pin 14, and at the moment, the connection between the locking claw 15 of the material changing gripper head mechanism 300 and the upper pipe base 8 is released (the state is shown in fig. 28);
thirdly, moving the middle push cylinder 18 of the material changing head grabbing mechanism 300 upwards, removing the thrust on the hook ring 11, and vertically moving the hook ring 11, the push rod 1 and the floating slide cylinder 7 upwards under the action of buoyancy; the multi-section sliding grooves on the floating sliding cylinder 7 gradually generate outward thrust on the ball anchor 6, and the outer side part of the ball anchor 6 is gradually pushed out of the ball anchor hole of the lower tube seat 2; when the hook ring 11 floats upwards, the cambered surface on the edge of the upper surface of the hook ring can push the self-locking hook 93 to rotate outwards around the self-locking hook pin shaft 92; when the spherical groove V on the floating sliding cylinder 7 is contacted with the ball anchor 6, the ball anchor 6 blocks the floating sliding cylinder 7 to stop moving upwards; at the moment, the outer part of the ball anchor 6 extends out of the lower tube seat 2 and is embedded into a locking groove on the inner wall surface of the hole of the reactor core grid plate 5, the middle part of the ball anchor is positioned in a ball anchor hole of the lower tube seat 2, the inner part of the ball anchor is contacted with a second vertical sliding groove IV and a spherical groove V of the floating microphone 7, and the ball anchor 6 is used as a stop pin and is positioned among the reactor core grid plate 5, the lower tube seat 2 and the floating sliding cylinder 7 to limit the mutual movement of the ball anchor; after the floating slide cylinder 7 stops moving up, the hook claw ring 11 is positioned at the upper part of the hook head of the self-locking hook claw 93 (the state is shown in fig. 29);
fourthly, the outer push barrel 17 of the material changing gripper mechanism 300 moves upwards, the thrust of the upper part of the slide block 96 in the self-locking claw box body 91 is released, the slide block 96 is enabled to move upwards along the guide pin 952 under the buoyancy of the lead-based coolant and the restoring force of the spring 951, and in the moving process, the inner inclined surface 962 of the slide block 96 can push the self-locking claw 93 to rotate inwards around the self-locking claw pin shaft 92; when the slide block 96 moves upwards to reach the maximum stroke, the inner side plane 963 of the slide block 96 is just in parallel contact with the outer side plane of the self-locking hook claw 93, so that the self-locking hook claw 93 cannot rotate outwards around the self-locking hook claw pin shaft 92. Meanwhile, an upper end boss of the self-locking hook claw 93 is also in contact with an upper end step surface of a self-locking hook claw mounting groove of the hook claw box shell 91 to limit the self-locking hook claw to rotate inwards around the self-locking hook claw pin shaft 92, so that the self-locking hook claw 93 is locked in position. At this time, the hook head of the self-locking hook 93 is just positioned on the lower end surface of the hook ring 11, so that the hook ring 11 cannot move downwards, the floating slide cylinder 7 is also constrained to move downwards due to the connection effect of the push rod 1, so that the floating slide cylinder 7 is constrained in the up-down moving direction, the position of the floating slide cylinder is fixed, the floating slide cylinder 7 firmly pushes the ball anchor 6 to the outside, the outer part of the ball anchor 6 is stably embedded into the locking groove of the inner wall surface of the hole of the reactor core grid plate 5, so that the new fuel assembly is locked on the reactor core grid plate 5, and finally the refueling grapple mechanism 300 is separated and proposed (the state is shown in fig. 30).
The above embodiments are only used for illustrating the present invention, and the structure, connection mode, manufacturing process, etc. of the components may be changed, and all equivalent changes and modifications performed on the basis of the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims (11)

1. A locking, unlocking and grabbing lifting device for a lead-based reactor fuel assembly is characterized by comprising a lower pipe seat buoyancy locking mechanism (100), an upper pipe seat self-locking mechanism (200) and a refueling grabbing head mechanism (300);
wherein the bottom nozzle buoyancy locking mechanism (100) comprises:
the reactor core grid plate (5) is provided with a through hole, and the inner wall of the hole of the reactor core grid plate (5) is provided with a plurality of locking grooves along the circumferential direction;
the lower pipe seat (2) is a cylindrical shell, forms the outer boundary of the lower pipe seat buoyancy locking mechanism (100), and is used for being positioned and inserted into the hole of the reactor core grid plate (5), and a plurality of ball anchor holes are formed in the lower pipe seat (2) along the circumferential direction in the region where the reactor core grid plate (5) is inserted;
the floating sliding cylinder (7) is a variable cross-section cylinder body, is coaxially arranged in the lower pipe seat (2) and can move vertically and axially along with buoyancy, and a plurality of sections of sliding grooves are formed in the outer wall surface of the lower part of the floating sliding cylinder (7);
the ball anchors (6) are respectively limited between the ball anchor hole of the lower pipe seat (2) and the multi-section sliding groove of the floating sliding cylinder (7), and can only move horizontally and axially along the ball anchor hole of the lower pipe seat (2);
the lower ends of a plurality of push rods (1) are connected with the floating sliding cylinder (7);
the top nozzle self-locking mechanism (200) comprises:
the upper tube seat (8) is a cylindrical shell and forms the outer boundary of the upper tube seat self-locking mechanism (200);
the self-locking claw boxes (9), a plurality of self-locking claw boxes (9) are arranged in the upper tube base (8);
the hook claw ring (11) is arranged in the upper tube seat (8) in a sliding manner, is connected with the upper end of the push rod (1) and is used for being matched with the self-locking hook claw box (9) to realize self-locking;
the reloading gripper head mechanism (300) comprises:
the lower end of the outward pushing cylinder (17) can be in contact with the self-locking claw box (9) and is used for pushing the self-locking claw box (9) downwards to complete unlocking;
the middle push cylinder (18) is coaxially and slidably arranged in the outer push cylinder (17), and the lower end of the middle push cylinder (18) can be in contact with the claw ring (11) and is used for pushing the claw ring (11) downwards;
the locking hook claws (15), a plurality of locking hook claws (15) are rotationally arranged on the middle push cylinder (18) and are used for hooking the upper pipe seat (8) when the middle push cylinder (18) moves downwards;
the inner push cylinder (12) is coaxially and slidably arranged in the middle push cylinder (18);
the roller boxes (16) are arranged on the inner push cylinder (12) and correspond to the locking hooks (15) one by one, and the roller boxes (16) are used for driving the locking hooks (15) to rotate when the inner push cylinder (12) moves up and down.
2. The locking, unlocking and grabbing lifting device according to claim 1, wherein a plurality of said ball anchor holes are arranged along the circumferential direction of said lower tube seat (2) at equal angular intervals, the diameter of each said ball anchor hole is slightly larger than the diameter of said ball anchor (6), the diameter of said ball anchor (6) is about three times of the wall thickness of said lower tube seat (2), the outer side edges of said ball anchor holes are inward arc-shaped closed-off ports, and the radian of said arc-shaped closed-off ports is fitted with the surface of said ball anchor (6) to prevent said ball anchor (6) from falling out of said lower tube seat (2) when moving horizontally and axially along said ball anchor holes;
meanwhile, a limiting boss is formed on the outer wall surface of the lower tube seat (2), the diameter of the limiting boss is larger than the diameter of the hole of the reactor core grid plate (5), and the limiting boss is used for limiting the downward insertion depth of the lower tube seat (2).
3. The locking, unlocking and grabbing lifting device according to claim 1, characterized in that the inner cavity of the floating sliding cylinder (7) is a through hole with equal diameter, the upper and lower wall surfaces of the floating sliding cylinder (7) are thicker, the middle wall surface is thinner, the upper end surface of the floating sliding cylinder (7) is provided with a plurality of threaded openings arranged circumferentially at equal angular intervals for connecting with the lower end of the push rod (1);
the multi-section sliding groove is divided into 5 sections from top to bottom: the first section is a first vertical sliding groove (I), the second section is a slope sliding groove (II), the third section is a transition sliding groove (III), the fourth section is a second vertical sliding groove (IV), the fifth section is a spherical groove (V), and the diameter of the spherical groove (V) is equal to that of the ball anchor (6).
4. The locking, unlocking and gripping lifting device according to claim 1, wherein a plurality of said self-locking claw boxes (9) are arranged at equal angular intervals along the circumferential direction of said upper pipe seat (8), each of said self-locking claw boxes (9) comprising:
the hook claw box body (91), the inner side of the hook claw box body (91) is provided with a self-locking hook claw mounting groove, and the lower part of the hook claw box body (91) is provided with a first sliding groove;
the self-locking hook claw (93) is placed in a self-locking hook claw mounting groove of the hook claw box body (91), the upper end of the self-locking hook claw (93) is rotatably connected with the hook claw box body (91) through the self-locking hook claw pin shaft (92), and the lower end of the self-locking hook claw (93) forms a hook head of the protruding hook claw box body (91);
the lower base (94) is used for tightly connecting the lower end of the claw box body (91) and the upper end of the upper pipe seat (8);
the sliding block (96) is arranged in a first sliding groove at the lower part of the hook claw box body (91) in a sliding manner, and the inner side of the sliding block can be in contact with the self-locking hook claw (93) and is used for blocking the self-locking hook claw (93) from rotating outwards;
and the elastic mechanism (95) is connected between the lower base (94) and the sliding block (96) and is used for driving the sliding block (96) to move up and down in the first sliding groove of the claw hooking box body (91).
5. The locking, unlocking and grabbing lifting device according to claim 4, wherein a stop pin (97) is arranged on the hook claw box body (91) located outside the self-locking hook claw (93) and used for limiting the outward rotation amplitude of the self-locking hook claw (93) around the self-locking hook claw pin shaft (92); the inner wall surface of the self-locking hook claw (93) is provided with a bulge protruding out of the hook claw box body (91), the position of the bulge is lower than that of the self-locking hook claw pin shaft (92), and the self-locking hook claw (93) can rotate outwards around the self-locking hook claw pin shaft (92) when the bulge is under the action of thrust.
6. The locking, unlocking and grabbing lifting device according to claim 5, wherein said first sliding grooves are formed on the left, right and outer sides of the lower portion of said claw box (91), said slider (96) has three side lugs (961) on the left, right and outer sides thereof, and said three side lugs (961) of said slider (96) are slidably disposed in said three first sliding grooves of said claw box (91), respectively; the upper end of a self-locking hook mounting groove of the hook claw box body (91) is provided with a step surface, the upper end of the self-locking hook claw (93) is provided with a boss, and the boss is matched with the step surface to limit the self-locking hook claw (93) to rotate inwards around the self-locking hook claw pin shaft (92); meanwhile, an inner slope surface (962) inclined from outside to inside is formed at the upper part of the inner side of the sliding block (96), and a vertical inner plane (963) is formed at the lower part of the inner side of the sliding block (96).
7. Locking, unlocking and gripping lifting device according to claim 6, characterized in that said elastic means (95) comprise:
the lower end of at least one guide pin (952) is fixedly connected to the lower base (94), and the upper end of the guide pin (952) penetrates through the side lug (961) of the sliding block (96) and then is fixedly connected with the claw box body (91);
a spring (951) sleeved on the guide pin (952) between the lower base (94) and the side lug (961) of the sliding block (96).
8. The locking, unlocking and grabbing lifting device according to claim 4, characterized in that a plurality of circumferential hook grooves arranged at equal angular intervals are formed on the inner wall surface of the upper part of the upper pipe seat (8) and used for connecting the material changing grabbing head mechanism (300); a plurality of self-locking claw box mounting grooves which are annularly arranged at equal angle intervals are formed in the middle of the upper tube seat (8) and used for mounting the self-locking claw boxes (9); the lower end face of the claw ring (11) is provided with threaded holes which are annularly arranged at equal angular intervals and are used for being in threaded connection with the upper end of the push rod (1);
meanwhile, the lower end face of the hook head of the self-locking hook claw (93) is in arc transition, and the outer edge of the upper end face of the hook claw ring (11) is in arc transition and used for pushing the lower end face of the hook head of the self-locking hook claw (93) outwards when moving upwards.
9. The locking, unlocking and gripping lifting device according to claim 1, wherein a guide support ring (3) is formed on an inner wall surface of the lower socket (2), and the inner wall surface of the guide support ring (3) is in contact with an upper outer wall surface of the floating slide cylinder (7) and forms a sliding pair to radially support the floating slide cylinder (7);
the lower baffle ring (4) is further formed on the inner wall surface of the lower tube seat (2) below the floating sliding cylinder (7) and used for limiting the vertical downward movement distance of the floating sliding cylinder (7);
meanwhile, a push rod supporting ring (10) is formed on the inner wall surface of the upper tube seat (8) above the floating sliding barrel (7), a guide hole with a diameter slightly larger than that of the push rod (1) is formed in the push rod supporting ring (10), and the push rod (1) penetrates through the guide hole to radially support the push rod (1).
10. The locking, unlocking and gripping elevating device according to claim 1, wherein a plurality of roller box installation slots are formed at the lower portion of said inner pushing cylinder (12) in a circumferential direction at equal angular intervals, and each of said roller boxes (16) comprises:
the roller box body (163) is arranged in the roller box mounting groove of the inner push cylinder (12);
the roller (161) is rotatably arranged in the roller box body (163) through the roller pin shaft (162), and the outer side part of the roller (161) protrudes out of the roller box body (163) and is in contact with the inner wall surface of the locking hook claw (15);
meanwhile, a plurality of locking claw mounting grooves which are circumferentially arranged at equal angle intervals are formed in the middle of the middle push barrel (18), and the locking claws (15) are rotatably connected in the locking claw mounting grooves through locking claw pin shafts (14); the lower part of the locking hook claw (15) forms a hook head protruding outwards, and the hook head is used for being inserted into a hook groove of the upper tube seat (8); the upper end of the inner wall surface of the locking hook claw (15) is an inclined inward arc surface, and the lower end of the inner wall surface is a vertical plane.
11. The locking, unlocking and gripping lifting device according to claim 6, wherein the lower end face of the outer pushing cylinder (17) is provided with cutouts matched with the three side lugs (961) of the sliding block (96) so as to facilitate pushing the side lugs (961) of the sliding block (96); an annular boss is formed on the inner wall surface of the outer pushing cylinder (17), and the annular boss is in contact with the outer wall surface of the middle pushing cylinder (18) and used for forming radial support for the middle pushing cylinder (18); a plurality of second sliding grooves which are circumferentially arranged at equal angle intervals are formed in the outer pushing cylinder (17) above the annular boss, a first sliding pin (13) is placed in each second sliding groove, the outer end of the first sliding pin (13) is arranged in each second sliding groove in a sliding mode, the inner end of the first sliding pin (13) is fixedly connected with the middle pushing cylinder (18), and therefore the mutual rotation and axial movement distance between the outer pushing cylinder (17) and the middle pushing cylinder (18) is limited;
simultaneously, open the upper portion of well push cylinder (18) has a plurality of third spout that the annular equiangular interval was arranged, place in the third spout second slip pin (19), the outer end of second slip pin (19) slides and sets up in the third spout, the inner of second slip pin (19) with interior push cylinder (12) fastening connection, restriction from this mutual rotation and the axial displacement distance between well push cylinder (18) and interior push cylinder (12).
CN201910958005.8A 2019-10-10 2019-10-10 Locking, unlocking and grabbing lifting device for lead-based reactor fuel assembly Active CN110600145B (en)

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