JPH0247592A - Handling tool for neutron measuring tube - 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 (Objective of the Invention) (Industrial Application Field) The present invention relates to a tool for handling a neutron measurement tube in a nuclear reactor, and particularly relates to a neutron meter 1q in which the spindle part of the neutron measurement tube is an upper grid plate. The present invention relates to a neutron measurement tube handling tool suitable for handling a neutron measurement tube that has been removed from a tube mounting hole.

(Prior Art) Generally, in constant meter inspection of a nuclear reactor such as a boiling water reactor, the neutron measurement tube is replaced after the fuel is replaced. The replacement work begins by moving the platform above the reactor core along the rails above the reactor, and using the auxiliary hoist installed on the bluff 1 platform, the replacement handling tool suspended from the tip of the wire rope is moved to the reactor. suspended in the water. Then, insert the replacement handling tool into the reactor core from the upper grid plate of the reactor, remove the spindle head of the neutron measurement tube that is engaged from below at the intersection of the upper grid plate from the engagement part,
The neutron measurement tube will be lifted above the reactor and moved to a spent fuel storage pool, etc.

Also, a new neutron measurement tube will be installed in the reactor! For polymerization, insert the neutron and measurement tube into the core through the gap between the upper grid plates using the replacement handling tool, insert the lower end of the neutron measurement tube into the guide tube that opens on the core support plate, and then insert the neutron measurement tube into the core housing. While being inserted and supported, the spindle head at the upper end is engaged with and installed at the intersection of the upper grid plate.

By the way, when the spindle head of a neutron measurement tube is removed from the engagement part of the upper grid plate, or when the spindle head of a new neutron measurement tube is installed into the engagement part of the upper grid plate, the spindle head is attached to the upper grid plate. The lower part of the neutron measurement tube may be disengaged from the engagement portion at the intersection of the plates and inserted into the guide tube and in-core housing (hereinafter referred to as a floating head). This is caused by aging of the upper grid plate and neutron measurement tube. In this case, since the replacement handling tool uses the upper grid plate as a gauge frame, it can be used with the spindle head of the neutron measurement tube that is in a fixed position relative to the upper grid plate, but the 70-ting head condition is cannot be used with spindle heads.

For this reason, a handling tool specifically designed for floating heads has conventionally been used. This handling tool inserts the spindle head of a neutron measurement tube, which has become a floating head, into a conical hole, and handles it by rotating the lower part of the spindle head with increased diameter.

(Problem to be Solved by the Invention) However, in improved boiling water reactors developed in recent years, the spindle head of the neutron measurement tube does not have to be increased in diameter, but is attached to the engagement part of the upper grid plate while keeping its small diameter. Now you can insert it and insert it. In addition, the curvature of the corners of the [,z lattice plate was also changed. For this reason, the conventional handling date could not be used, and it became necessary to develop a new neutron measurement tube and a new handling tool attached to the upper grid plate.

The present invention has been made in consideration of the above circumstances.)(]
- The purpose of the present invention is to provide a neutron measurement tube handling tool that can easily handle a neutron measurement tube that has reached a tipping head state without causing any damage, and that can quickly replace the neutron measurement tube. .

[Structure of the invention]

(Means for Solving the Problems) A neutron measurement tube handling tool according to the present invention moves a plurality of cylinders sideways simultaneously by supplying pressurized water to a support that can be suspended from a wire rope or the like. A hydraulic cylinder mechanism,
A hydraulic supply mechanism that supplies pressurized water to this hydraulic cylinder mechanism, a spring mechanism that presses each cylinder toward the center, and a split tube that grips the lower part of the increased diameter part of the neutron measurement tube by the hydraulic cylinder mechanism and spring mechanism. In the hydraulic cylinder mechanism, a plurality of fixed pistons extending laterally are integrally connected to the lower end of the column, and a plurality of cylinders surrounding each fixed screw 1 supply pressurized water. The spring mechanism is mounted on a fixed piston so as to move laterally, and the spring mechanism has a spring receiver extending laterally from the bottom of the column along each of the cylinders, and a spring receiver extending from the tip of the spring receiver to the center of each cylinder. The split tube is provided with a spring that urges it to the side, and the split tube has a cylindrical shape with a plurality of arms that are integrally fixed to each of the cylinders, and the lower end is formed into a conical shape whose diameter decreases downward. , a step part is formed on the inner surface of this split tube that can come into contact with the lower part of the increased diameter part of the neutron measurement tube, and this split tube is inserted from above the upper grid plate to the lower part of the increased diameter part of the neutron measurement tube. It is long enough to hold.

(Function) Since the lower part of 2/3 of the total length of the neutral 111W is inserted into the guide tube and in-core housing, the total length of the neutral one is 70W.
-The spindle head in the state of
The spindle is biased by a spring provided at the bottom of the spindle so that it leans against the corner of the upper lattice plate.

In order to handle a total of 31'H of neutrality in such a state, first, a neutron measurement tube handling tool (hereinafter referred to as the handling tool) is suspended from a wire rope or the like and suspended into the reactor water. Then, when it comes above the upper grid plate, when pressure water is supplied to the hydraulic cylinder mechanism by the water pressure supply IItil, each cylinder slides to the side against the pressing force of the spring of the spring mechanism due to this pressure water. do. As each cylinder moves laterally along the fixing screw I, each arm of the split tube fixed to each cylinder twists.

Thereafter, the handling tool is further lowered, the split tube is inserted into the frame of the upper grid plate, the arm of the split tube is inserted between the spindle head and the upper grid plate, and the handling tool is further suspended by its own weight. In this case, since the split tube is formed with a length sufficient to grip the bottom of the increased diameter part of the neutron measurement tube from above the upper grid plate, the 7-megment of the split tube is connected between the spindle head and the upper grid plate. When inserting a nuclear reactor into the darkness, etc.
It can be easily seen from the F side.

When the handling tool is suspended by its own weight, the spindle head is introduced into the split tube, and the tip of the arm of the split tube reaches below the increased diameter portion of the spindle. At this time, when the pressure water is removed from the hydraulic cylinder mechanism by the water pressure supply mechanism, each cylinder slides toward the center due to the bias of the spring mechanism, the multiple arms fixed to each cylinder close, and the split tube becomes solid. At the same time, the descending portion of the increased diameter portion of the spindle is gripped by the stepped portion formed on the inner surface side of the split tube.

After that, when the handling tool was lifted, a total of 111 II neutral tubes were pulled out of the reactor, and the neutron measuring tube was grabbed by the replacement handling tool, etc., and the replacement work of the neutron 51 measuring tube could be continued. Can be done.

(Embodiment) An embodiment of the neutron measurement tube handling tool according to the present invention will be described with reference to FIGS. 1 and 2.

The neutron measurement tube handling tool consists of a support 1 that can be hung on a wire robe, etc., a hydraulic cylinder mechanism 2 that slides a plurality of cylinders laterally when pressured water is supplied, and a hydraulic cylinder mechanism 2 that slides a plurality of cylinders laterally. a water pressure supply mechanism 3 that supplies pressurized water to the mechanism 2;
A spring R mechanism 4 that presses each of the cylinders toward the center, and a half tube 7 as a segment υj tube that grips the lower part of the increased diameter part 6 of the neutron measurement tube 5 by means of the hydraulic cylinder mechanism 2 and the spring mechanism 4. Be prepared.

The support column 1 extends in the vertical direction, and a shroud plate 9 is fixed to the top.
A top plate 10 is fixed to the upper end FQI of this shroud plate 9. A stud 11 is screwed onto the top surface of the top plate 10, and a terminal fitting 12 provided at the tip of a wire rope extending from an auxiliary voice 1- on a service platform (not shown) is connected to the stud 11.

A hydraulic cylinder 11M42 is provided at the lower end of the branch office 1. The hydraulic cylinder mechanism 2 includes a pair of fixed pistons 14a extending laterally from an extension shaft 13 connected to the lower end of the column 1.
, 14b are provided. Each fixed piston 14a, 14b
By supplying pressure water to the fixing screw 1hen 14
A pair of cylinders 1 that can be slid laterally along a and 14b
5a, 15b are provided so as to surround each fixed piston 14a, 14b. In each cylinder 15a, 15t), a head 16 for guiding pressure water into the cylinder chamber is screwed together from the cylinder tip side via an A-ring, and a piston part 17 equipped with an O-ring is housed in the cylinder chamber. .

The spring mechanism 4 is provided with one spring receiver fixed to the lower part of the column 1. The spring receiver 19 is attached to each cylinder 15a, 15.
b, extending laterally along the cylinder 15a, 1
5b is formed in a shape to slidably support it. Springs 20a, 20b are provided between the tip of the spring receiver 19 and the seven ring portions of the cylinders 15a, 15b to bias the cylinders 15a, 15b toward the center. A spring guard 21 is fixed to the tip of the spring receiver 19 to guide the expansion and contraction of the springs 20a and 20b. In addition, the code 22 is the cylinder 15
a, shows a fixed slide guiding the lateral sliding of 15b;

The half pipe 7 has, for example, a pair of arms 7a, 7 having a semi-cylindrical cross section.
b, consisting of a pair of arms 7a.

7b constitutes a cylindrical shape, for example. Each arm 7a,
7b is integrally fixed to the 7 flange portion of each cylinder 15a, 15b, and opens laterally as the cylinders 15a, 15b slide. The lower end of the half tube 7 is formed into a conical shape whose diameter decreases downward, and the lower end of each arm 7a, 7b is formed thin.

The inner surface of the half tube 7 has a step part 24 that can come into contact with the lower part of the increased diameter part 6 formed at the center of the spindle of the neutron measurement tube 5, and a step part 25 that can come into contact with the upper part of the increased diameter part 6. is formed. These steps 24, 25 have a shape that adapts to the outer shape of the spindle 23 when the tube half 7 is closed. The length of the half tube 7 is formed to be long enough to grasp the lower part of the increased diameter part 6 of the neutron measuring tube 5 from above the upper grid plate 26.

Water pressure supply fil that supplies pressure water to the water pressure cylinder mechanism 2
I43 is provided with a flexible tube 27 that is connected to the water pressure pump shown in the figure installed above the reactor, and this flexible tube 27 is connected to the socket plug 2.
8. Connected to T-shaped pipe 30 via metal fitting 29. The T-shaped tube 30 is fixed to the column 1, and includes a pair of elbows 31, a flexible tube 32, a soot plug 33, and a straight tube 34.
It is connected to the head 16 of each cylinder 15a, 15b via. The flexible tube 32 is connected to each cylinder 15.
It is formed to be flexible and have an appropriate length so that it can follow the sliding movement of parts a and 15b.

Next, the operation of the above embodiment will be explained.

A water pressure pump, a water tank for water supply and drainage, and a switching valve for switching between pressurization, stoppage, and depressurization are installed on the floor above the reactor or on the Levis platform. and,
Depressurize the switching valve, turn on A3, and connect the flexible tube 27.
Connect the ends of the At this time, the half tube 7 is in a closed state. Furthermore, a terminal fitting 12 provided at the tip of the wire rope of the auxiliary voice 1 is connected to the stud 11.

Thereafter, the service platform is moved to above the upper grid plate 26 on which the neutron measurement tube 5, which is in a floating head state, is installed, and the auxiliary hoist is operated to lower the handling tool into the reactor water. When the handling tool reaches above the upper grid plate 26, the switching valve is switched to establish a pressurizing circuit, and the water pressure pump is driven to supply pressurized water. The pressure water is supplied through the flexible tube 2 of the water pressure supply mechanism 3.
7, passes sequentially through a T-shaped tube 30, a flexible tube 32, and a straight tube 34, and is supplied to the cylinder chambers of each cylinder 15a, 15b.

When pressure water is supplied into the cylinder chamber, each cylinder'/1
5a and 15b resist the pressing force of springs 20a and 20b,
They slide laterally along fixed pistons 14a, 14b, respectively. When the cylinder 158.15b slides sideways,
The half tube 7 integrally fixed to these cylinders 15a, 15b opens.

When the piston part 17 and the inner surfaces of the cylinders 15a and 15b come into contact, the needle of the water pressure gauge of the water pressure pump above the reactor rises rapidly, so the switching valve switches pressurization to a halt.

Then, with the half pipe 7 open, the handling tool is further suspended by the auxiliary hoist, and the half pipe 7 is placed on the upper lattice plate 26.
1 (the arms 7a and 7b of the split tube 7 are inserted between the upper grid plate 26 and the spindle 23 of the neutron measurement tube 5. In this case, the lower end of the half tube 7 is The spindle 23 can be easily attached to the spindle 23 because it is formed into a conical shape that becomes smaller in diameter toward
and the upper grid plate 26, and the spindle 23 can be separated from the upper grid plate 26.

In this way, the handling tool is further lowered until the lower part of the half tube 7 reaches below the increased diameter part 6 of the spindle 23.

In this case, the half pipe 7 is inserted from above the upper lattice plate 26 into the Nakatake Ryoke i1! Since the length is long enough to grasp the lower part of the increased diameter 16 of the l-tube 5, there is no need to insert the main body of the handling tool into the frame of the upper grid plate 26, and it can be easily grasped from above the reactor. The positional relationship between the half tube 7 and the spindle 23 can be visually confirmed, making the operation easier.

After the lower part of the half pipe 7 has moved below the increased diameter part 6, when the switching valve is switched to pressure reduction and the pressure water in the cylinders 15a and 15b is discharged through the water pressure supply mechanism 3, the springs 20a and 20b are released.
Due to the pressing force, each cylinder 15a, 15b is urged toward the center and slides along the fixed piston 14a, 14b. When the cylinders 15a and 15b are biased toward the center,
The half tube 7 integrally fixed to each cylinder 15a, 15b is closed, and its step 24 grips the lower part of the increased diameter part 6, and the step 25 grips the spindle 23 above the increased diameter part 6. grasp.

After gripping the spindle 23, the auxiliary vehicle ist is hoisted up, the handling tool is hoisted up, and the neutron measurement tube 5 is hoisted out of the reactor. In this case, springs 20a, 20b
Since the half-tube 7 is closed, there is no danger that the neutron measurement tube 5 will separate from the half-tube 7 during lifting even if a problem with the hydraulic hose or the like occurs. After the neutron measurement tube 5 is pulled out of the reactor, it is held in a replacement handling tool or a moving handling tool, and the subsequent work is continued.

As described above, according to the above embodiment, the neutron measurement tube 5 in the 70-ting head state can be easily handled without being damaged, and the replacement work of the neutron measurement tube 5 can be performed quickly and smoothly. can.

In the above actual fk example, the split pipe was the half pipe 7, but
This may be divided into three parts. In this case, the hydraulic cylinder mechanism, the spring mechanism, and the hydraulic supply mechanism have shapes extending in three directions. Furthermore, although the above embodiment describes the case where the handling tool is applied to a modified IQ type boiling water reactor, it can be similarly applied to a conventional boiling water reactor.

〔Effect of the invention〕

The neutron measurement tube handling tool according to the present invention includes a hydraulic cylinder mechanism that slides a plurality of cylinders laterally by supplying pressure water to a branch that can be hung on a wire 70, etc. The water L that supplies pressurized water to this hydraulic cylinder mechanism [the supply mechanism, the spring mechanism that presses each of the above cylinders toward the center, and the lower part of the increased diameter part of the neutron measurement tube is gripped by the hydraulic cylinder mechanism and the spring mechanism. A split pipe is provided,
In the above-mentioned hydraulic cylinder mechanism, a plurality of fixed pistons extending laterally are integrally connected to the lower end of the column, and a plurality of cylinders surrounding each fixed piston slide laterally along the fixed piston by supplying pressurized water. φIJ, and the spring mechanism includes a spring receiver extending laterally from the lower part of the column along each of the cylinders, and a spring biasing each cylinder toward the center from the tip of the spring receiver. The split tube has a cylindrical shape with a plurality of arms that are integrally fixed to each cylinder, and the lower end has a conical shape whose diameter decreases downward. A step part is formed below the increased diameter part of the neutron measurement tube, and this split tube has a length sufficient to grasp the lower part of the increased diameter part of the neutron measurement tube from above the upper grid plate. Since the neutron measurement tube is formed into a floating head, it can be easily handled without damaging it, and the neutron measurement tube can be replaced quickly and smoothly.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of a neutron measurement tube handling tool according to the present invention, and FIG. 2 is a plan view of the above embodiment. DESCRIPTION OF SYMBOLS 1... Support material, 2... Hydraulic cylinder mechanism, 3... Water I [supply gate structure, 4... Spring mechanism, 5... Neutron measurement tube, 6... Increased diameter part, 7 ...half υ1 tube, 7a, 7b・
...Arm, 14a, 14b...Fixing screw 1-N, 1
5a, 15b...Cylinder, 16...Head, 19
...Spring holder 1), 20a, 2Qb...Spring, 23
...Spindle, 24, 25...Step part, 26...
Upper grid plate, 27...Flexible tube. Applicant's agent Hisashi Hatano

Claims (1)

[Claims] A hydraulic cylinder mechanism that slides a plurality of cylinders laterally by supplying pressurized water to a support that can be suspended from a wire rope or the like; a hydraulic supply mechanism that supplies pressurized water to the hydraulic cylinder mechanism; It is equipped with a spring mechanism that presses each cylinder toward the center, and a split tube that grips the lower part of the increasing diameter part of the neutron measurement tube by these hydraulic cylinder mechanisms and spring mechanisms. A plurality of fixed pistons extending toward each other are integrally connected, and a plurality of cylinders surrounding each fixed piston are provided to slide laterally along the fixed pistons by supplying pressurized water, and the spring mechanism A spring receiver extends laterally from the bottom of the column along each of the cylinders, and a spring is provided from the tip of the spring receiver to urge each cylinder toward the center, and the split pipe is integrally attached to each cylinder. A plurality of fixed arms form a cylindrical shape, and the lower end is formed into a conical shape whose diameter decreases downward, and the inner surface of this split tube is in contact with the lower part of the increasing diameter part of the neutron measurement tube. The neutron measurement tube is characterized in that the split tube is formed with a sufficient length to grasp the bottom of the increasing diameter part of the neutron measurement tube from above the upper grid plate. handling tools.