JPH02151796A - Internal pump handling device - Google Patents

Abstract

PURPOSE:To maintain horizontal movement in a stable condition by making a guide in contact with the inside of a reactor pressure vessel of a structure of combined uses of vertical and turning movements and providing the guide in contact with the outer face of shroud with turning wheels. CONSTITUTION:At first, a pump portion is grasped by a handling device 30, supports 24, 28 are extended by air cylinders 26, 29, and the inner face of a reactor vessel 2 is put into contact with guide rails to perform upward movement. When the movement is continued to pass the upper end of the guide rails, the center of the device 30 is shifted to the side of a shroud 15 by the resilient force of springs 25 and the wheels 32 are in contact with the shroud 15. Next, the device 30 is horizontally moved by a fuel exchanging machine. Thereby, the vessel 2 can be avoided colliding with the shroud 15 and the stable condition thereof can be held during horizontal movement of the device 30.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention provides an internal pump handling device for attaching and detaching pump parts of an internal pump built in a boiling water nuclear reactor underwater. Regarding.

(Prior Art) An internal pump 1 built into an improved boiling water nuclear reactor is constructed as shown in FIG.

Namely, the open sleeve 2a at the bottom of the reactor pressure vessel 2
The motor case 3 is inserted into the reactor pressure vessel 2, and its upper end is welded to the open sleeve 2a, and the lower half of the motor case 3 is suspended outside the reactor pressure vessel 2.

Inside the motor case 3, a motor shaft 4 and a pump shaft 5, which are keyed so that they can be separated in the vertical direction, are rotatably coaxially housed.A rotor 6 is integrally fixed to the outer periphery of the motor shaft 4. A stator 7 is arranged on the outer periphery with a predetermined gap.

Further, a grip bolt 8 is screwed to the upper end of the pump shaft 5, and an impeller 9 is attached thereto. There is a diffuser lO on the outer periphery of the impeller 9, the lower end of the diffuser 10 is coupled to the upper end of a stretch tube 11, and the stretch tube 11 is coupled to a stretch tube nut 12, thereby fixing the diffuser 10 on the opening sleeve 2a. has been done. Furthermore, differential user 1
0 and the stretch tube 11 are keyed to the open sleeve 2a to prevent rotation. In the figure, 13 is a closing cover, 14 is a secondary seal, and 15 is a shroud.

In order to inspect the internal pump 1 configured as described above after the start of plant operation, it is necessary to disassemble and install each component of the internal pump 1 remotely. The pump shaft 5 and impeller 9 are integrated, and the diffuser 10 and stretch tube 11 are integrated, and the reactor pressure vessel 2
It is necessary to remove it above the annular space surrounded by the shroud 15 and the shroud 15.

For this reason, an internal pump handling device 20 shown in FIGS. 4 to 6 has been proposed. As shown in FIG.
A latch mechanism 21 that grips the spherical upper end of the internal pump 1, and a circumferential groove 1. It has a hook mechanism 22 that engages the hook with Oa. Latch mechanism 21 and hook mechanism 22
is driven by air pressure supplied from an air hose (not shown) to engage and release each engaging portion of the internal pump 1. Further, the handling device 20 is provided with a guide used for positioning during vertical movement.

This guide consists of a guide in contact with the inner surface of the reactor pressure vessel 2 and a guide in contact with a guide rail 16 attached to the shroud 15 shown in FIGS. 6 and 7. The guide that is in contact with the inner surface of the reactor pressure vessel 2 includes an axle 23 that is in contact with the inner surface, a support 24 that supports the wheels 23, and an axle 23 that is in contact with the inner surface of the reactor pressure vessel 2.
It is composed of a spring 25 for pressing the support 3 against the inner surface, and an air cylinder 26 for expanding and contracting the support 24. Further, the guide in contact with the guide rail 16 includes a pair of axles 27 in contact with the guide rail 16, and a support 28 that supports the axle 27.

It is composed of an air cylinder 29 that expands and contracts the support 28. This handling device 20 is suspended by a wire rope or the like from a refueling platform movably installed above the reactor pressure vessel 2, and is movable in the vertical and horizontal directions.

The air cylinders 26 and 27 are remotely driven by air pressure supplied from an air hose (not shown).

Next, the movement to inspect the internal pump 1 and to take it out from the reactor pressure vessel 2 will be explained. In an annular space surrounded by the reactor pressure vessel 2 and the shroud 15, an internal pump handling device 20 is seated on the pump 1 in order to take out pump parts of the internal pump 1, and the latch mechanism 21 or the hook mechanism 22 is used to pump the pump. The parts are grabbed and moved upwards by the hoisting action of the refueling plant platform. In this case, handling tool 2
The air cylinders 26 and 29 of the guides 0 act in the direction of extending the supports 24 and 28 to bring the axle 23 into contact with the inner surface of the reactor pressure vessel 2, and also cause the axle 23 to contact the inner surface of the reactor pressure vessel 2.
7 is brought into contact with a guide rail 16 attached to the shroud 15 in a protruding manner. Handling device 20 moved upward
will be moved further horizontally. It is the seventh
As shown in Figure 8, which shows the ■-■ arrow direction in the figure, there are approximately 10 internal pumps 1, and the shroud 15
This is because there are two passage ports 15b in the flange 15a, and it is necessary to move the handling device 20 in the circumferential direction to below the passage ports 15b. During this horizontal movement, the air cylinders 26 and 29 of the guide of the handling device 20
By working in the direction of contracting the supports 24 and 28, the clearance between the handling device 20 and the inner surface of the reactor pressure vessel 2 and the clearance between the handling device 20 and the outer surface of the shroud 15 are ensured. Note that the spring 25 maintains a certain width of suppressing force even if there are variations in the dimensions of the guide rail 16 and the inner surface of the reactor pressure vessel 2.

(Problem to be Solved by the Invention) When horizontally moving the pump parts of the internal pump 1 while being gripped by the handling device 20, the handling device 20 is moved in its current state without any guide as described above. is about 20m
Since it is suspended from the refueling plant platform above, its position and direction of rotation are not determined, making it unstable. This is because when moving the handling device 20 in the circumferential direction, the lifting point of the platform is moved in the circumferential direction at an extremely slow speed, and the handling device 20 follows the movement, but water flow inside the reactor pressure vessel 2 If this occurs, the handling device 20 may be shaken and make unexpected movements. As a result, handling device 2
0 may collide with the reactor pressure vessel 2 or the shroud 15 at a speed exceeding the permissible speed.

Further, the wire rope suspending the handling device 20 may come into contact with the flange of the shroud 15 and cause damage.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an internal pump handling device capable of maintaining a stable state of the handling device during horizontal movement of the handling device.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a handling device with a guide for use during horizontal movement, which is an engagement device that removably engages with pump parts of an internal pump built into a nuclear reactor. In an internal pump handling device that is suspended from a trolley on a platform and has a mechanism, a guide in contact with the outer surface of the shroud, and a guide in contact with the inner surface of the reactor pressure vessel, the guide in contact with the inner surface of the reactor pressure vessel moves vertically. The shroud is also characterized in that it has a structure that can be used for both turning and movement, and that the guide in contact with the outer surface of the shroud is provided with turning wheels or pads that are different from those used for vertical movement.

(Function) To remotely take out the pump parts of the internal pump for inspection, the internal pump handling device is seated on the pump, the pump parts are grasped, and the pump parts are moved upward by the hoisting action of the refueling platform. . In this case, the guide of the handling device is in contact with the inner surface of the reactor pressure vessel and the outer surface of the guide rail. Next, move horizontally to below the passage hole of the shroud flange. At this time as well, the guide for horizontal movement of the handling device is in contact with the inner surface of the reactor pressure vessel and the outer surface of the shroud. Further at the end of the horizontal movement.

The support of the guide is shortened and the external dimensions of the handling tool are reduced to allow it to pass through the passage opening by upward movement. In this way, the pump components can be removed from the reactor pressure vessel.

Note that movement during installation of the pump or movement of the handling device alone can also be performed according to the above procedure or the reverse procedure.

(Example) An example of the present invention will be described below with reference to FIG. Note that parts common to those in FIGS. 4 to 6 are denoted by the same reference numerals, and redundant explanation of the common parts will be omitted.

FIG. 1 shows one embodiment of the present invention, and shows the sixth embodiment of the conventional example.
This is an internal pump handling device 30 that allows the guide of the handling device shown in the figure to be used during vertical movement and horizontal movement.

Further, the guide is in contact with the inner surface of the reactor pressure vessel 2, and this guide includes a spherical wheel 31 with a ball bearing structure, a support 24 that supports the wheel 31,
It is composed of a spring 25 for pressing the axle 31 against the inner surface of the reactor pressure vessel 2, and an air cylinder 26 for expanding and contracting the support 24. The spherical axle 31 is rotatable in multiple directions, and has a dual-purpose structure such that it rolls into contact with the inner surface of the reactor pressure vessel 2 even when the handling tool moves horizontally and vertically. Also,
The guide is in contact with the outer surface of the shroud 15, and a pair of axles 32 is provided on the support 28 of the wheel 27 that is in contact with the guide rail 16, and this axle 32 is configured to roll into contact with the outer surface of the shroud 15 during horizontal movement. There is.

In the internal pump handling device having such a configuration, movement for taking out the pump parts of the internal pump 1 for inspection will be explained.

The pump parts are gripped by the handling device 30 and moved upwards by the hoisting action of the refueling platform. In this case, by extending the supports 24 and 28 with the air cylinders 26 and 29, the wheels 31 and the axles 27 are brought into contact with the inner surface of the reactor vessel 2 and the guide rail 16, and the wheels 31 and the axles 27 rotate smoothly. Can move upwards. In this state, the 6th
As in the state shown in the figure, the position of the handling device is determined by the distance of the axle 27 from the guide rail 16, so the axle 32 used for horizontal movement is in a non-contact state with the shroud 15. As the handling tool 30 continues to rise and passes the upper end of the guide rail 16, the center of the handling tool 30 shifts toward the shroud 15 due to the elastic force of the spring 25, and the axle 3
2 will come into contact with shroud 15 as shown in FIG. In addition, in this state, the axle 27 used for vertical movement
Since the guide rail 16 is not present, there is no contact. Next, the handling tool is moved horizontally by the refueling machine. In this case, the axle 31 is in contact with the inner surface of the reactor pressure vessel 2,
Further, the axle 32 is in contact with the outer surface of the shroud 15 and is in rolling contact. Therefore, even if a water flow occurs in the reactor pressure vessel 2, the handling tool 30 does not become unstable in position, and even if the trajectory of the hanging position of the refueling machine does not follow the correct circumference, the reactor pressure vessel 2 and the space surrounded by the shroud 15 can be smoothly moved. Eventually, the handling device 30 opens the passage port 15 of the flange 15a of the shroud 15.
When it reaches below b, the air cylinders 26, 27 are operated remotely, the supports 24, 28 are contracted, the external dimensions of the handling device 30 are reduced, and the handling device 30 is pulled up and passed through the passage port 15b.

Next, another embodiment of the present invention will be described with reference to FIG.

First, let's look at the guide on the reactor pressure vessel 2 side.

Instead of the spherical axle with the ball bearing structure shown in FIG. 1, if a roller-shaped axle supported on a rotatable support as shown in FIG. 2, that is, a caster structure is used, the horizontal movement of the handling device 30 , and can roll into contact with the inner surface of the reactor pressure vessel 2 in both cases of vertical movement.

It is a guide on the shroud 15 side, and is a smooth warped band 34 with a flat surface that eliminates the rolling contact.
It is also possible to do this. In this case, in order to eliminate the possibility of damaging the shroud 15, the pad 34 is preferably made of an aluminum alloy or a resin material.

As explained above, by providing a guide during horizontal movement, movement can be performed smoothly and stably. Due to rolling or sliding friction, it is predicted that the refueling machine platform will not be able to follow the movement of the refueling machine platform, making it difficult to position the handling tool on the guide rail below the passageway or on the internal pump installation location. Ru.

To deal with this, for example, a protruding stopper may be provided on the outer surface of the shroud at each positioning position, and the positioning may be performed by contacting the wheel of the handling tool. In this case, by changing the installation level of the positioning stoppers on the 10 guide rails and moving the handling tool horizontally at the level corresponding to each stopper, the handling tool will come into contact with the stopper on the predetermined guide rail according to its level. This makes positioning easier.

〔Effect of the invention〕

According to the present invention, collision between the reactor pressure vessel and the shroud can be avoided, thereby making it possible to maintain a stable state during horizontal movement of the handling device.

Improves safety during handling.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the internal pump handling device according to the present invention, Fig. 2 is a plan view showing another embodiment of the present invention, -1 Fig. 3 is a longitudinal section showing the internal pump. 4 is a partially cutaway front view showing the engaged state of the latch mechanism and impeller of the conventional internal pump handling device, and FIG. Front view partially cut away showing the engaged state, No. 6
The figures are a front view showing the guide of the handling device in Fig. 4, Fig. 7 is a vertical sectional view schematically showing the inside of the reactor pressure vessel, and Fig. 8 is a longitudinal sectional view schematically showing the inside of the reactor pressure vessel.
The figure is a plan view showing the direction of the arrow ■-■ in FIG. 7. 1...Internal pump 2...Reactor pressure vessel 2
1... Latch mechanism 22... Hook mechanism 23
...Car ea24...Support 25...Spring 26 Air cylinder 2
7. Car It'! 28...Support 29...Air cylinder 30...Internal pump handling device 31...Wheel (spherical shape) 32...Wheel 33...Axle
34...Pad (8733) Agent Patent Attorney Yoshiaki Inomata (1 person)

Claims (1)

[Claims] (1) It has an engagement mechanism that removably engages with the pump parts of the internal pump built into the reactor, a guide that contacts the outer surface of the shroud, and a guide that contacts the inner surface of the reactor pressure vessel. When handling and installing an internal pump that is suspended from a trolley, the guide in contact with the inner surface of the reactor pressure vessel has a structure capable of both vertical movement and rotational movement, and the guide in contact with the outer surface of the shroud has a structure in which rotation is different from vertical movement. An internal pump handling device characterized by being equipped with wheels or pads.