JPS613086A - Treater for internal pump - 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 [Old Field of the Invention] The present invention relates to 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.

[The height of invention]

Conventionally, boiling water reactors are equipped with a jet pump in the reactor pressure vessel, and a portion of the reactor water in the reactor pressure vessel is pumped out and pressurized by a recirculation pump, and then supplied to the jet pump as driving water. This jet pump circulated reactor water through the reactor core. However, such a system had a complicated structure and had 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. That is, in the figure, 1 is a reactor pressure vessel, a shroud 2 is provided within the reactor pressure vessel 1, and a reactor core 3 is accommodated within the shroud 2. A plurality of internal pumps 4, for example 12, are installed around the bottom of the reactor pressure vessel 1.
is provided. Then, the reactor water in the reactor pressure vessel 1 descends in the downcomer 5 formed between the outer circumferential surface of the shroud 2 and the inner circumferential surface of the reactor pressure vessel l, and the above-mentioned internal pump 4... * is sent to the lower part of the reactor core 3, and flows into this reactor core 3 from below. 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 by a steam dryer 7, it is sent to a turbine (not shown), etc. . Further, the separated water is sent to the core 3 again by the internal pumps 4 along with the water supplied from the water supply sparger 8. In addition, a plurality of (approximately 200
A control rod drive mechanism 9 (not shown) is provided, and these control rod drive mechanisms 9 drive a control rod (not shown).
is inserted into or withdrawn from the reactor core 3, and is configured to control the reactivity, etc. of the reactor core 3.

The internal pump 4 is constructed as shown in FIG. 2. That is, reference numeral 10 denotes a pump section, which is composed of a diff user 11 and an inlet 212. The diffuser 11 is fixed to the tip of a stub tube 15 protruding from the bottom of the reactor pressure vessel 1 by a stretch tube 13 and a stretch tube nut 14. Further, 16 is a motor case, which is welded to the reactor pressure vessel 1 and is provided to protrude from the bottom surface. And this motor case 1
A water immersion type motor 17 is housed inside the motor 6 . A motor cover 17a is attached to the lower end of the motor 17, and this motor cover 17a abuts the lower surface of the motor case 16, and is tightened and fixed by nuts 19 threaded onto stud bolts 18. , the motor 17 is fixed to the motor case 16 while maintaining liquid tightness. Further, this motor 17 and the impeller 12 are connected by a shaft 20, and the impeller 12 is driven via this shaft 20.

[Problems with background technology]

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, first disconnect the motor 17 and shaft 20, then tighten the nut 19...
Remove the motor 17 and pull it downward from the motor case 16, then pull out the impeller 12 and shaft 20 upward,
Furthermore, remove the stretch tube nut and remove the diff 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.

Assembling and installing this internal pump nose... is done in the reverse order of the above.

Incidentally, inside the pedestal are a control rod drive mechanism 9 protruding from the bottom of the reactor pressure vessel 1, a neutron detector assembly (not shown), and a large number of pipes connected to these.
wiring), and there is little space available. Further, the motor 17 is large in size and heavy in weight. Therefore, the work of removing the 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 the work, further reducing work efficiency.

[Purpose of the invention]

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.

[Summary of the invention]

The present invention relates to a Tanabata handling machine that attaches and detaches the motor of an internal pump provided at the bottom of a reactor pressure vessel to a motor case, and an annular running machine provided along the inner circumferential surface of an intermediate portion of a reactor pedestal. a motor handling machine lifting mechanism for raising and lowering the motor handling machine from the running path to the position of the internal pump; a moving cart for moving the motor in the circumferential direction along the running path; It is equipped with an elevating mechanism that is formed on the peripheral wall of the reactor pedestal and moves the equipment up and down from the equipment loading/unloading entrance to the above-mentioned running path. Therefore, for example, when removing the motor, the motor handling machine is raised from the running path to the position of the internal pump using the motor handling machine lifting mechanism, the motor is removed, the motor is lowered to the running track, and the motor handling machine is moved circumferentially along this running track. The device is moved to a position corresponding to equipment loading/unloading, and is lowered from the travel path to the equipment loading/unloading entrance by the lifting mechanism, and then transported out of the pedestal. Therefore, since the motor can be moved in the middle part of the pedestal where there is a relatively large space, work efficiency can be greatly improved. .

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Third
50 in the figure is a nuclear reactor building, and a reactor containment vessel 51 is provided within this reactor building. A pressure suppression chamber 52 is formed within this reactor containment vessel 51. Further, 53 is the ceiling of the building, and this ceiling 53
A running rail 54 is provided along the running rail 54, and a lane 55 for running overhead is supported on the running rail 54 so as to be able to run freely. Further, 56 is a fuel storage pool for storing nuclear fuel, and 57 is an equipment storage pool for storing removed in-core equipment. Further, around the reactor containment vessel 51, rooms 58 and 59 are provided in which the equipment of each side is 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 as described above.
..., a control rod drive mechanism 9, etc. are provided.

Further, 101 is a cylindrical pedestal that supports the reactor pressure vessel 1, and an equipment removal port 102 is formed at 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 position. The 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.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 the movable cart 12 is guided along the annular rails 121, 121.
3a is configured to run.

Rails 122, 122 are provided along the radial direction on the upper surface of the movable trolley 123a, and the movable trolley 123a is further placed on the rails 122, 122 so as to be movable in the radial direction. . And this mobile trolley 1
A motor support stand 124 and a motor handling machine elevating mechanism 125 are placed on 23b.

Next, the configurations of the motor support stand 124 and the motor handling machine elevating mechanism 125 will be explained. Reference numeral 150 denotes a driving body of the motor handling machine lifting mechanism 125, and this driving body 150 is placed on the moving cart 123b. Moreover, a motor handling machine 124 is further placed on this driving body 150. The motor support stand 124 is configured to automatically attach and detach the nuts that fix the motors 17 to the motor case 16, and to automatically attach and detach the motors 17. The drive body 150 is provided with a pair of rotation drive mechanisms 151, 151. Also,
Reference numerals 152 and 152 are screws such as ball screws, and bearings 153 and 153 are provided at the upper ends of the 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. Pole nuts 155, 155, 156, 15 in the middle part
6 are screwed together. In addition, the internal pump 4
. . ., motors 17 . And the ball screw 152,
Bearings 153, 153 at the upper end of 152 are connected to the motor case 16
... is attached to the hook members 157, 157, and the ball neck) 155, 155° 156, 156 is the motor 1
7... and the hook member 158 of the motor support stand 124,
158, 159° 159, and connector 1
54.154 is the rotational drive mechanism 151,1 of the drive body 150
51. therefore,
When the ball screws 152, 152 are rotated by the rotation drive mechanism 151, 151, the pole nut 155
, 155, 156, and 156 are spirally moved, and the motor 17 and motor support stand 124 are configured to move up and down.

Note that these ball screws 152, 152 are configured to be removed when not in use. Further, the hook members 153, 153 of the motor case 16 are attached to the bolts 16.
By removing these bolts 160...K, the ball screw 152°1 is removed together with the hooking member 157.157.
52 can be removed.

Further, an upper platform 170 for working is provided above the intermediate platform 120, and this upper platform 170 has an annular shape, and has passage holes 171 and 171 corresponding to the positions of the internal pumps 4, and so on. . . are formed, and the motor 17 is attached and detached through these passage holes 171 . In addition, a pedestal 101 is located near the equipment loading/unloading entrance 102.
An elevating mechanism 180 that moves up and down along the inner circumferential surface is provided.

Reference numeral 181 denotes a lifting platform, which is configured to move up and down between the equipment unloading port 102 and the intermediate platform 120t. Further, a lower platform 190 is provided below the intermediate platform 120, and a motor cask 191 that accommodates the motor 17 is placed on this lower platform 190. Moreover, a rail 192 and an electric hoist 193 that moves along the rail 192 are provided above the lower platform 190, and the electric hoist 193 is configured to be able to lift the motor cask 191. In addition, a passage hole 194 is formed in the lower platform 190 corresponding to the position directly below the equipment loading/unloading entrance 102, and the motor cask 191 lifted by the electric hoist 193 is suspended through this passage hole 194 to the bottom of the pedestal 101. It is configured to be lowered.

Additionally, rails 195, 195 are provided at the bottom of the pedestal 101 to transport the movable cart 123 lowered by the lifting platform 181 to the equipment loading/unloading entrance 102.

Next, the operation of the above embodiment will be explained. First, the movable cart 123 on which the motor support stand 124 and the driving body 150 are mounted
a along the annular rails 121, 121, and position it directly below the internal pump 4 from which the motor is to be removed. Next, install the ball screws 152, 152,
Raise the motor support stand 124 and remove the motor. Next, the ball screws 152, 152 are rotated in the opposite direction, and the removed motor 17 and motor support stand 124 are lowered and placed on the moving carriage 123. Then, the ball screws 152, 152 are removed. Next, move the movable cart 123 on which the removed motor 17 is placed onto the annular rails 121, 1.
21 in the circumferential direction, and moves to the position of the lifting mechanism 180. Then, the lifting platform 181 is moved to the moving trolley 123a.
The movable cart 1238 is moved in the radial direction and placed on the lifting platform 181. And this lifting platform 1
81 and move the mobile cart 123b to the pedestal 101.
and move it onto the rails 195, 195.

Next, the motor 17 is moved to the rail 195 together with the moving cart 123b.
．． 1'95, and move to the front of the equipment loading/unloading entrance 102. Next, the motor cask 191 is hoisted up from the lower platform 190 by the electric hoist 193 and lowered through the passage hole 194 and placed over the motor 17, and this motor 17 is housed in the motor cask 191. Then, the motor 17 housed in the motor cask 191 is carried out of the pedestal 101 through the equipment carry-in/out entrance 102 by a carry-in/out mechanism (not shown).

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

〔Effect of the invention〕

As described above, the present invention includes a motor handling machine for attaching and detaching an internal pump motor installed at the bottom of a reactor pressure vessel to a motor case, and an annular motor installed along the inner circumferential surface of an intermediate portion of a reactor pedestal. a running path, a motor handling machine lifting mechanism for lifting and lowering the motor handling machine from the running path to the position of the internal pump, a moving cart for moving the motor in a circumferential direction along the running path, and a motor handling machine for moving the motor in a circumferential direction along the running path; and a lifting mechanism for raising and lowering the equipment from an equipment loading/unloading entrance formed in the peripheral wall of the reactor pedestal to the running path. Therefore, for example, when removing the motor, the motor handling machine is raised from the travel path to the position of the internal pump by the motor handling machine lifting mechanism.
The motor is removed and lowered to the running path, moved in the circumferential direction on this running path to a position corresponding to the equipment loading/unloading entrance, and then lowered from the running path to the equipment loading/unloading entrance by the lifting mechanism and transported out of the pedestal. Therefore, since the motor can be moved along the inner circumferential surface of the pedestal in the middle part of the pedestal where there is a relatively large space, the effects are great, such as greatly improving work efficiency. be.

[Brief explanation of drawings]

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 an embodiment of the present invention, and FIG.
The figure is a schematic diagram of the entire reactor, Figure 4 is a schematic diagram, Figure 5 is a plan view of the intermediate platform, Figure 6 is a front view of the motor handling machine lifting mechanism, and Figure 7 is the same as in Figure 6. -■ Arrow view, Figure 8 is a front view of the hook member, Figure 9 is IX of Figure 8-
IX arrow view, Figure 10 is a plan view of the upper platform,
FIG. 11 is a plan view of the lower platform, FIG. 12 is a view taken from the store in FIG. DESCRIPTION OF SYMBOLS 1... Reactor pressure vessel, 4... Internal pump, 16... Motor case, 17... Motor, 101
...Pedestal, 103...Rotating platform,
12°... Intermediate platform, 121... Annular rail, 122... Branch rail, 123... Moving trolley, 124... Motor support stand, 125... Motor handling machine lifting mechanism, 180... - Lifting mechanism, 181... Lifting platform. Figure 1 /97 Figure 27 V

Claims (1)

[Claims] 1. A motor handling machine that attaches and detaches the motor of the internal pump provided at the bottom of the reactor pressure vessel to and from the motor case; and an annular running path provided along the inner peripheral surface of the intermediate portion of the reactor pedestal; a motor handling machine lifting mechanism that lifts and lowers the motor handling machine from the running path to the position of the internal pump; a moving carriage that moves the motor in the circumferential direction along the running path; An internal pump handling device comprising: a lifting mechanism for raising and lowering the equipment from an equipment loading/unloading port formed in a peripheral wall thereof to the running path.