JPS61797A - Detachable device for collet joint of nuclear reactor fuel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field to which the invention pertains]

This invention relates to reactor fuel handling equipment for pressure tube nuclear reactors, particularly a collet that is installed in a fuel exchange machine to attach and detach a collet joint that connects a fuel assembly and a Jahei plug during fuel exchange. Regarding a joint attachment/detachment device.

[Prior art and its problems]

First, in Figure 3, which shows an overview of the fuel exchange equipment for a pressure tube reactor, 1 is the reactor core, 2 is the pressure tube that makes up the core, and inside the pressure tube 2 are fuel assemblies 3° shielding plugs 4 ．．
Seal plugs 5 are loaded in order, and the fuel assembly 3 and shielding plug 4 are removably connected via a collet joint, which will be described later. On the other hand, the refueling of the core is performed by a refueling machine 6 running below the core I. As is well known, this fuel exchanger has a grab mechanism, magazine mechanism, etc. built into its pressure vessel.
After connecting the fuel exchanger 6 to the pressure pipe 2, the fuel assembly, shield plug, seal plug, etc. are pulled out and loaded by operating the grab mechanism. Here, the structure of the above-mentioned collet joint is shown in FIGS. 4 and 5. The collet joint 7 has a tie plate 8 attached to the lower end of the fuel assembly 3 and a collet part attached to the upper end of the stiffening plug 4. 9, and the collet portion 9 has, at its upper end, comb-like claw pieces 9a arranged in the circumferential direction that form claws that engage with engagement grooves on the inner circumferential surface of the tablate 8. In this configuration, in order to separate the collet joint 7, first apply force from the outer circumferential side of the collet part 9 as shown by arrow F, and squeeze each claw piece 9a of the collet part inward as shown by the chain line to separate the claws. Then, either pull the fuel assembly 3 upward or pull it down below the shield plug 4 to separate the two. Conversely, when connecting the shielding plug 4 to the fuel assembly 3, the collet portion 9 is connected in the same manner as described above.
By squeezing the claw piece 9a by applying force from the outer circumferential side, and releasing the force after inserting the collet part into the tie plate, the claw piece of the collet part will elastically return and the claw will be engaged with the tie plate side. The two are connected by engaging with the matching groove. By the way, in the past, the work of separating the spent fuel fuel assembly 3 and the hardening plug 4 during refueling, or connecting the new fuel fuel assembly and the hardening plug with the hardening plug, was performed when the fuel changing machine and the fuel changing pool were connected. A collet joint attachment/detachment device is installed in the transfer port between the two, and the collet joint attachment/detachment device is used to carry out the fuel exchange while the fuel assembly is suspended in the transfer boat by the fuel exchange machine. Here, the configuration of a conventional collet joint attachment/detachment device is shown in FIGS. 6 and 7. Reference numeral 10 denotes a base having a passage hole 10a opening in the center for guiding up and down the core components such as fuel assemblies and shield plugs. , the hole 10 is formed on the base.
A rotary ring 11 is slidably supported by a support member 12 provided on a base 10 on the outer peripheral side of a, and furthermore, an operating cylinder 1 as a driving means is disposed diagonally on the rotary ring 11.
3a and 13b are connected via an operating shaft 14. On the other hand, on the circumference of the rotating ring, the rear end portions of eight collet squeeze pawls 15, the same number as the pawl pieces of the collet portion, are pivotally connected with pins with their tips facing the passage hole 10a, and A long cam groove 15a formed in each aperture claw 15 is fitted with a fixed guide pin 16 arranged on the inner circumferential side of the rotary ring 11 to be guided and supported. With this structure, by operating the operating cylinders 13a and 13b in opposite directions, the rotating ring 11 rotates in the circumferential direction, and the collet aperture claws 15 are guided by the guide pins 16 as shown by arrow A. Then, the robot is operated forward and backward toward the passage hole 10a. Therefore, when attaching and detaching the collet joint, place the collet part described in Fig. 4 on the base 1.
When the collet is inserted into the passage hole 10a of No. 0, the tips of the collet restricting claws 15 are pressed from the outer periphery to the collet part by operating the operation cylinder, so that the claw pieces of the collet part are pushed into the inner periphery side, and in this state, the fuel The collet joints are connected and separated by lifting and lowering the assembly using a fuel inlet/output machine. On the other hand, recently, with the aim of shortening the work time during fuel exchange and downsizing the fuel exchange machine, the above-mentioned collet joint attachment/detachment device has been installed at the upper end of the fuel exchange machine to connect the fuel assembly and the shielding plug. 1. A method has been proposed in which the separation operation is performed in parallel with the loading and unloading of fuel assemblies into the core, and the fuel assemblies and shield plugs are housed separately in magazines in the pressure vessel of the fuel exchanger. There is. However, in this case, if the above-mentioned collet joint attachment/detachment device is installed and used as is in a fuel exchanger, the following problems will occur. In other words, in the conventional fuel exchange method,
When attaching or detaching a collet joint, a shielding plug is set in the collet joint attaching/detaching device, and while the collet part is in a constricted state, the fuel assembly is moved up and down to connect and separate the two. When installing and removing collet joints in parallel with fuel exchange work,
Due to the fuel exchange work procedure, it is necessary to connect and separate the collet joint by lifting and lowering the shield plug using a grab mechanism while leaving part of the fuel assembly in the pressure pipe on the core side. However, if the collet section of the constraint plug is squeezed by the collet joint attachment/detachment device and the deflection plug is moved up and down, the collet section will be rubbed by the collet squeeze pawl 15 of the collet joint attachment/detachment device and be damaged if the conventional structure is used. Otherwise, the collet drawing claws may be damaged by the vertical moment load. In addition, since the guide bin 16 is structurally arranged on the inner circumferential side of the rotating ring 11 and the collet drawing claw 15 is configured to be interlocked and controlled in the radial direction by this guide bin, the radial dimension is large. The space factor is also bad. In addition, foreign matter such as crud and sludge enters the pressure vessel of the fuel exchanger from the pressure pipe side of the reactor core, but the conventional structure has an open top and has many mechanically sliding parts. This foreign matter accumulates in the collet joint attachment/detachment device, and in particular enters its sliding portion, causing galling, making it difficult to maintain its integrity.

[Purpose of the invention]

This invention was made in consideration of the above points, and its purpose is to improve the conventional device, reduce the number of parts per sliding part in the device, and provide a collet joint attachment/detachment with a compact and highly reliable structure. The goal is to provide equipment.

[Key points of the invention]

In order to achieve the above object, the present invention includes an annular housing having a guide passage hole in the center through which core components such as fuel assemblies and shielding plugs pass, and an annular housing that is housed in the housing and rotates in the circumferential direction of the housing. movably supported on bearings,
and a rotary cam having diagonal cam grooves distributed over the circumference of one end surface thereof, a rotation driving means for the rotary cam, and a guide supported in a radial direction distributed in a circumferential direction of the housing, and a guide for the rotary cam. a tip guide roller housed in a housing so that the bottle is engaged in a cam groove of the rotary cam, and the tip moves in and out of the guide passage hole in a radial direction according to the rotation of the rotary cam; It consists of a push rod for squeezing the collet part.

[Embodiments of the invention]

FIGS. 1 and 2 show a cross-sectional view and a vertical cross-sectional view of a collet joint attachment/detachment device according to an embodiment of the present invention, and its structure includes an opening in the center of a guide passage hole 17a through which core components pass. an annular housing 17, and a rotary cam 19 rotatably supported within the housing via a bearing 18.
, a push rod 20 which is also supported within the housing and whose motion is controlled by the rotary cam, and a drive section for the rotary cam. Of these, the rotary cam 19 has diagonal cam grooves 19a distributed and lined up on the circumference of its upper end surface, and is connected diagonally to operating cylinders 13a and 13b as drive units via an operating shaft 14. ing. On the other hand, the push rod 20 includes a rod body 20a that is evenly distributed around the circumference of the housing 17 and guided and supported in the radial direction, a guide roller 20b that comes into contact with a collet portion attached to the inner end of the rod body, and a rod body It consists of a guide bin 20c with a roller that protrudes downward from a midway point and fits into the cam #19a. In the above configuration, when the rotary cam 1q is rotated in the circumferential direction within the housing 17 by driving the operation cylinders 13a and 13b, the push rod 20 is driven by the rotary cam and linearly moves in the radial direction by controlling the cam groove 19a. The guide roller 20b at the tip is moved forward and backward toward the central passage hole 17a in accordance with the rotating direction of the rotary cam. therefore,
When attaching and detaching the collet joint, the collet part on the shielding plug side is inserted and set into the passage hole 178 of the I/Using 17, and by performing the above operation in this state, the guide roller 20b of each push rod 20 is moved as shown in FIG. It comes into contact with the ml tooth-shaped claw pieces of the collet part shown in FIG. 5, and the claw pieces of the collet part are squeezed and released. When lifting or lowering the shielding plug with the collet pressed and its claws squeezed, the guide roller is in contact with the outer periphery of the collet, so the sliding resistance is small, and the fuel assembly and shield plug are in contact with each other. Separation and connection between the two can be performed smoothly. Further, according to the above structure, the rotary cam 19. Both push rods 20 are housed within the housing 17, and therefore, when installed and used in a fuel exchange machine, even if foreign matter such as crud or sludge settles and enters the Kikushina Exchange Matunai from the core side, there is no need to worry. , these foreign objects are inside the rotary cam housing. The probability of buildup and galling on the push rod bearing support is low, and reliability can be improved compared to conventional structures. Furthermore, since the rotary cam 19 is configured to directly control the linear motion of the push rod 20, the number of parts is reduced compared to the conventional structure, and the radial dimension in particular can be reduced to make the structure smaller and more compact.

【Effect of the invention】

As described above, according to the present invention, there is provided an annular housing having an internal passage hole opening in the center through which core components such as fuel assemblies and shielding plugs pass, and an annular housing that is housed in the main housing and extends in the circumferential direction of the housing. A rotary cam rotatably supported by a bearing and having diagonal cam grooves distributed around the circumference of one end surface thereof, a rotation driving means for the rotary cam, and a radial direction distributed in the circumferential direction of the housing. The housing is guided and supported by the rotary cam, and its guide pin is engaged in a cam groove of the rotary cam, so that the tip thereof moves in and out of the guide passage hole in a radial direction according to the rotation of the rotary cam. This collet joint is made up of a push rod for squeezing the collet part with a tip guide roller housed inside the unit, and can be installed inside the fuel exchange machine to perform attachment/detachment operations of the collet joint in parallel with the fuel exchange process. As an attachment/detachment device, it is less affected by crud that enters the fuel exchanger from the core side, and can be smoothly connected to and separated from the fuel assembly by lifting and lowering the shielding plug using a grab mechanism, and is compact. It is possible to provide a collet joint attachment/detachment device that can be configured compactly and has high practical value such as fogging.

[Brief explanation of drawings]

1 and 2 are a cross-sectional view and a longitudinal sectional view of a collet joint attachment/detachment device showing the configuration of an embodiment of the present invention, respectively, FIG. 3 is a schematic diagram of a fuel exchange facility for a pressure tube reactor, and FIG. 5 and 5 are a longitudinal cross-sectional view and a cross-sectional view taken along arrow V-V in FIG. 4, respectively, showing the structure of a collet joint, and FIGS. 6 and 7 are cross-sectional views, respectively, showing the structure of a conventional collet joint attachment/detachment device. FIG. l: Reactor core, 3: Fuel assembly, '4: 'L Yahei plug, 6: Fuel exchanger, 7: Collet joint, 8: Tie plate, 9: Collet part, 13a, 13b: Operation as driving means Cylinder, 17: Housing, 17
a: Guide passage hole of core component, 18: Bearing of rotary cam, 19: Rotary cam, 198: Cam groove of rotary cam, 20: Push rod, 20b = Guide roller,
20c Ni guide bin. 17α Figure 12

Claims (1)

[Scope of Claims] 1) An attachment/detachment device for a collet joint that connects a fuel assembly and a shielding plug, in which a guide passage hole through which core components such as the fuel assembly and shielding plug pass is opened in the center. an annular housing; a rotary cam that is housed within the housing and supported by a bearing so as to be rotatable in the circumferential direction of the housing; and that has diagonal cam grooves distributed around the circumference of one end surface of the rotary cam; and the rotary cam. The rotation driving means is distributed in the circumferential direction of the housing and is guided and supported in the radial direction, and the guide pins thereof are engaged in the cam grooves of the rotary cam, and the tip of the rotary cam is driven by the rotation of the rotary cam. A collet joint attachment/detachment device for nuclear reactor fuel, characterized in that it is comprised of a collet part squeezing push rod with a tip guide roller housed in a housing so as to move in and out of the guide passage hole in a radial direction. . 2) In the collet joint attachment/detachment device according to claim 1, the collet joint attachment/detachment device is installed in a fuel exchange machine, and at that location, the collet joint attachment/detachment device is installed between the fuel assembly and the shielding plug during fuel exchange. A reactor fuel collet joint disconnection device, characterized in that it performs attachment and detachment operations.