JPH0311677B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a boiling water nuclear reactor equipped with an internal pump, in which the motor of the internal pump is removed and carried out of the reactor pedestal, and the motor is removed from the reactor pedestal. This invention relates to an internal pump handling device for transporting and installing a pump from outside the pedestal.

[Conventional technology]

Conventionally, a boiling water reactor is equipped with a jet pump in the reactor pressure vessel, and a part of the reactor water in the reactor pressure vessel is taken out, pressurized by a recirculation pump, and sent to the jet pump as drive water. This jet pump circulated reactor water through the reactor core. However, such a system has a complicated structure and has problems such as the piping connecting the jet pump and the recirculation pump forming a boundary with the reactor water.

In order to solve these problems, a boiling water reactor equipped with an internal pump as shown in FIGS. 1 and 2 was developed. In other words, 1 in the figure
is a nuclear reactor pressure vessel, and a shroud 2 is provided within this reactor pressure vessel 1, and a reactor core 3 is accommodated within this shroud 2. A plurality of internal pumps 4, for example 12, are provided around the bottom of the reactor pressure vessel 1. And this reactor pressure vessel 1
The reactor water inside the reactor descends through the downcomer 5 formed between the outer circumferential surface of the shroud 2 and the inner circumferential surface of the reactor pressure vessel 1, and is pumped below the reactor core 3 by the internal pumps 4 described above. This reactor core 3 is sent from below.
flow inside. The reactor water that has flowed into the reactor core 3 is boiled by the heat generated by the nuclear reaction, and flows upward as a two-phase flow of water and steam. This two-phase flow of water and steam is separated into water and steam by a steam separator 6, and after moisture is removed from the separated steam in a steam dryer 7, it is sent to a turbine (not shown) or the like. Sent. Also,
The separated water is sent to the core 3 again by the internal pumps 4 along with the water supplied from the water supply spargeer 8. Furthermore, a plurality (approximately 200) control rod drive mechanisms 9 are provided at the bottom of the reactor pressure vessel 1, and control rods (not shown) are driven by these control rod drive mechanisms 9. It is inserted into or withdrawn from the reactor core 3 and is configured to control the reaction rate of the reactor core 3 and the like.

The internal pump 4... is the second
It is configured as shown in the figure. That is, reference numeral 10 denotes a pump section, which is composed of a differential user 11 and an impeller 12. The diff user 11 is fixed by a stretch tube 13 and a stretch tube nut 14 to the tip of a stub tube 15 protruding from the bottom of the reactor pressure vessel 1. Reference numeral 16 denotes a motor case, which is welded to the reactor pressure vessel 1 and protrudes from the bottom surface. A water immersion type motor 17 is housed within this motor case 16. A motor cover 17a is attached to the lower end of this motor 17.
The bolts 7a abut against the lower surface of the motor case 16 and are tightened and fixed by nuts 19 threaded onto the stud bolts 18, thereby maintaining fluid tightness and fixing the motor 17 to the motor case 16. Further, this motor 17 and the impeller 12 are connected by a shaft 20, and the impeller 12 is driven via this shaft 20.

[Problem to be solved by the invention]

The internal pumps 4 are periodically disassembled and removed, and the removed parts are inspected and repaired at another location (outside the reactor containment vessel). To disassemble and remove this internal pump 4..., first disconnect the motor 17 and shaft 20,
Remove the nuts 19 and pull the motor 17 downward from the motor case 16, then pull out the impeller 12 and shaft 20 upward, then remove the stretch tube nut 14 and remove the differential user 11 upward. The motor 17 passes through the cylindrical pedestal that supports the reactor pressure vessel 1 and is carried out of the pedestal through an equipment carry-in/out port formed in the peripheral wall of the pedestal. Incidentally, the assembly and installation of this internal pump 4... is performed in the reverse order of the above.

By the way, there is a reactor pressure vessel 1 inside the pedestal.
The control rod drive mechanism 9 protruding from the bottom of the control rod drive mechanism 9..., a neutron detector assembly (not shown), and a large number of piping and wiring connected to these are accommodated, so there is little space available. Further, the motor 17 is large in size and heavy in weight. Therefore, the work of removing this motor 17 from the motor case 16 and carrying it out of the pedestal, or the work of carrying this motor 17 into the pedestal and attaching it to the motor case 16 is extremely troublesome and the work efficiency is low. Moreover, the high radiation level inside the pedestal limited the amount of time workers could spend there, and sometimes it was necessary to change workers midway through work, further reducing work efficiency.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to make it possible to efficiently and easily perform the work of removing and installing the motor of an internal pump. The purpose of the present invention is to provide an internal pump handling device.

[Means to solve the problem]

In order to achieve the above object, the internal pump handling device of the present invention is a motor handling device that removes a motor from an internal pump provided at the bottom of a nuclear reactor pressure vessel, and attaches a motor to the internal pump. means, and a motor removed from the internal pump or a motor attached to the internal pump is mounted, and conveys the motor in the circumferential direction of the reactor pedestal at a predetermined height within the reactor pedestal, and at a specific location. a conveyance means for conveying the motor in the radial direction of the reactor pedestal at the same height as the predetermined height; and a conveyance means formed at a predetermined position on the radial movement line along which the conveyance means conveys and on a peripheral wall portion of the lower part of the reactor pedestal. and an elevating mechanism that moves the conveying means up and down in the vertical direction along the reactor pedestal peripheral wall.

[Effect]

According to the above configuration, when removing the motor, for example, the motor is removed from the internal pump by the motor handling means, and the removed motor is placed on the conveying means. Then, the conveying means is moved in the circumferential direction within the reactor pedestal, and further moved in the radial direction toward the pedestal peripheral wall, thereby transporting the motor to the vicinity of the pedestal peripheral wall. Next, the transport means is lowered together with the motor to the equipment loading/unloading entrance by the lifting/lowering mechanism, and is transported out of the pedestal. Therefore, the motor can be moved in the middle part of the pedestal, where there is a relatively large space, so that work efficiency can be greatly improved.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 3, 50 is a nuclear reactor building, and a reactor containment vessel 51 is provided within this reactor building 50. A pressure suppression chamber 52 is formed within this reactor containment vessel 51. Further, 53 is the ceiling of the building, and a traveling rail 54 is provided along this ceiling 53.
4 supports an overhead traveling crane 55 so as to be freely movable. Further, 56 is a fuel storage pool for storing nuclear fuel, and 57 is an equipment storage pool for storing extracted in-core equipment. Further, around the reactor containment vessel 51, rooms 58 and 59 are provided in which various types of equipment are housed. The reactor pressure vessel 1 described above is accommodated within the reactor containment vessel 51. At the bottom of the reactor pressure vessel 1, there are a plurality of internal pumps 4 described above...
..., a control rod drive mechanism 9, etc. are provided. Reference numeral 101 is a cylindrical pedestal that supports the reactor pressure vessel 1, and an equipment loading/unloading port 102 is formed in the lower part of the peripheral wall of the pedestal.
A rotating platform 103 is provided in the middle of the pedestal 101 as shown in FIG. This rotating platform 103 has a substantially circular shape, and has an annular rail 105 attached to the pedestal 101 side via support members 104...
It is guided by and can rotate freely in a horizontal plane.
The rotating platform 103 is configured to be rotated in a horizontal plane by a drive mechanism (not shown) and stopped at any desired position. And this rotating platform 103
is provided with a control rod drive mechanism attachment/detachment device for attaching and detaching the control rod drive mechanisms 9.

An internal pump handling device for attaching and detaching the motor 17 of the internal pump 4 is provided within the pedestal 101, and the configuration of this internal pump handling device will be described below. In the figure, reference numeral 120 denotes an intermediate platform, which has an annular shape and is located at an intermediate portion within the pedestal 101 and provided along the inner circumferential surface of the pedestal 101. A running path, for example, annular rails 121, 121, is provided on the intermediate platform 120, and a moving carriage 123a is configured to run along the annular rails 121, 121. Rails 122, 122 are provided along the radial direction on the upper surface of this moving cart 123a (see FIG. 5).
A movable trolley 123b is further placed on top so as to be movable in the radial direction. And this mobile trolley 123
A motor handling machine 124 and a motor handling machine elevating mechanism 125 are placed on b.

Next, the configurations of the motor handling machine 124 and the motor handling machine lifting mechanism 125 will be explained with reference to FIGS. 6 and 7. 150 is motor handling machine lifting mechanism 1
25, and this driver 150 is placed on the moving cart 123b. Moreover, a motor handling machine 12 is further provided on the drive body 150.
4 is placed. This motor handling machine 124 automatically attaches and detaches the nuts fixing the motors 17... to the motor case 16, and the motors 17...
It is configured so that it can be attached and detached automatically. The drive body 150 is provided with a pair of rotation drive mechanisms 151, 151. Also, 15
Reference numerals 2 and 152 are screw rods, for example, ball screws, and bearings 153 and 153 are provided at the upper ends of these ball screws 152 and 152, respectively, and connectors 154 and 154 are attached to the lower ends of the ball screws 152 and 152, respectively. Ball nuts 155, 155, 156, 156 are screwed into the intermediate portion. Furthermore, hook members 15 are provided on both sides of the motor case 16 of the internal pump 4, the motor 17, and the motor handling machine 124, respectively.
7,157,158,158,159,159 are provided. The bearings 153, 153 at the upper ends of the ball screws 152, 152 are attached to the hook members 157, 157 of the motor case 16, and the ball nuts 155, 155,
156, 156 are the motor 17... and the hook members 158, 158, 159 of the motor handling machine 124,
159, and the connectors 154, 15
4 is a rotational drive mechanism 151, 151 of the drive body 150
was configured to be connected to. Therefore, when the ball screws 152, 152 are rotated by the rotation drive mechanism 151, 151, the ball nuts 155, 155, 156, 156 are screwed, and the motor 17 and the motor handling machine 124 are moved up and down. has been done. As shown in FIGS. 8 and 9, the hook members 157, 157 of the motor case 16 are attached to the motor case 16 by bolts 160, and by removing these bolts 160... This hooking member 157, 157 together with the ball screw 15
2, 152 can be removed from the motor case 16, and the ball screws 152, 152 can be removed from the motor case 16 when not in use.

Further, as shown in FIG. 4, an upper platform 170 for working is provided above the intermediate platform 120, and this upper platform 170 has an annular shape (see FIG. 10), and each internal pump 4 Passing holes 171... are formed corresponding to the positions of..., and these passing holes 1
The motor 17 is attached and detached through 71.... In addition, the equipment loading/unloading entrance 1
An elevating mechanism 180 that moves up and down along the inner peripheral surface of the pedestal 101 is provided near the pedestal 101 . 1
Reference numeral 81 is the lifting platform, and the equipment loading/unloading entrance 102
It is configured to move up and down between the platform and the intermediate platform 120. Further, below the intermediate platform 120 is a lower platform 19.
A motor cask 191 housing the motor 17 is mounted on this lower platform 190 (see FIGS. 11 and 12).
Moreover, a rail 192 and an electric hoist 193 that moves along the rail 192 are provided above the lower platform 190, and the motor cask 191 can be lifted up by the electric hoist 193.
In addition, a passage hole 194 is formed in the lower platform 190 in a position directly above the equipment loading/unloading entrance 102, and the motor cask 191 lifted by the electric hoist 193 is suspended through this passage hole 14 to the bottom of the pedestal 101. It is configured to

Also, at the bottom of the pedestal 101 is a lifting platform 181.
Rails 195, 195 are provided for transporting the movable cart 123c lowered by the device to the equipment loading/unloading entrance 102.

In this embodiment, the motor handling machine 124 and the motor handling machine lifting mechanism constitute motor handling means,
The moving carts 123a, 123b, 123c and the rails 121, 122 constitute a transport means.

Next, the operation of the above embodiment will be explained. First, the movable cart 123a on which the motor handling machine 124 and the drive body 150 are mounted is moved along the annular rails 121, 121, and positioned directly below the internal pump 4 from which the motor is to be taken out. Next, the ball screws 152, 152 are attached, the motor handling machine 124 is raised, and the motor is removed. Next, the ball screws 152, 152 are rotated in the opposite direction, and the removed motor 17 and motor handling machine 124 are lowered and placed on the moving carriage 123b. Then, the ball screws 152, 152 are removed.
Next, the movable cart 123a on which the removed motor 17 is placed is moved in the circumferential direction along the annular rails 121, 121, and is moved to the position of the lifting mechanism 180. Then, the lifting platform 181 is raised to the height of the moving carriage 123a, and the moving carriage 123b is moved in the radial direction and placed on the moving carriage 123c on the lifting platform 181. Then, lower this lifting platform 181,
The moving cart 123c is lowered to the bottom of the pedestal 101 and moved onto the rails 195,195.

Next, the motor 17 is moved to the moving carts 123b, 123
c along the rails 195, 195, and move to the front of the equipment loading/unloading entrance 102. Next, the lower platform 190 is moved by an electric hoist 193.
Lift up the upper motor cask 191 and open the passage hole 1.
94 and placed over the motor 17, and the motor 17 is housed in the motor cask 191. Then, the motor 17 housed in the motor cask 191 is passed through the equipment loading/unloading entrance 102 to the pedestal 1 by a loading/unloading mechanism (not shown).
01 Transport outside.

In addition, when installing the motor, perform the above procedure in reverse.

〔Effect of the invention〕

As described above, according to the present invention, the motor can be moved horizontally and vertically along the inner surface of the pedestal in the middle part of the pedestal, where there is a relatively large space, thereby greatly improving work efficiency. The effects are great, such as the ability to improve performance.

[Brief explanation of the drawing]

1 and 2 show a boiling water nuclear reactor equipped with an internal pump, with FIG. 1 being a schematic configuration diagram and FIG. 2 being a longitudinal sectional view of the internal pump. 3 to 13 show one embodiment of the present invention, FIG. 3 is a schematic diagram of the entire reactor, FIG. 4 is a schematic diagram of the interior of the pedestal, and FIG. 5 is a plan view of the intermediate platform. Fig. 6 is a front view of the motor handling machine lifting mechanism, Fig. 7 is a view in the direction of - arrow in Fig. 6,
FIG. 8 is a front view of the hook member, FIG. 9 is a view taken along the - arrow in FIG. 8, FIG. 10 is a plan view of the upper platform, and FIG. 11 is a plan view of the lower platform.
12 is a view taken along arrows XII-XII in FIG. 11, and FIG. 13 is a view taken along arrows - in FIG. 4. 1... Reactor pressure vessel, 4... Internal pump, 16... Motor case, 17... Motor,
101... Pedestal, 103... Rotating platform, 120... Intermediate platform, 121
...Annular rail, 122...Rail, 123a,
123b, 123c...Moving trolley, 124...Motor handling machine, 125...Motor handling lifting mechanism, 1
80... Lifting mechanism, 181... Lifting platform.

Claims (1)

[Claims] 1. A motor handling means for removing the motor from the internal pump provided at the bottom of the reactor pressure vessel or attaching the motor to the internal pump, and a motor removed from the internal pump or a motor attached to the internal pump. is mounted, and transports the motor in the circumferential direction of the reactor pedestal at a predetermined height within the reactor pedestal, and transports the motor in the radial direction of the reactor pedestal at a specific location at the same height as the predetermined height. between a predetermined position on the radial movement line along which the conveying means is conveyed and an equipment loading/unloading port formed in the peripheral wall of the lower part of the reactor pedestal. a lifting mechanism that moves up and down in the vertical direction along the section;
An internal pump handling device equipped with: