JPS61102901A - Inspection track of pressure container - 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] [Field of Application of the Invention] The present invention relates to a track that guides the running of an automatic device that conducts periodic inspections of pressure vessels, etc., which are difficult or impossible for inspectors to access, such as nuclear couplants. In particular, if the environment in which it is installed experiences significant temperature changes, the test track is suitable for absorbing thermal expansion.

[Background of the invention]

FIG. 8 is a perspective view showing a conventional track 3 provided between the reactor pressure vessel 1 and the heat insulator 2.

The temperature at the location where this track 3 is provided rises to about 300° C. when the nuclear reactor is in operation. This orbit 3 is a biological shielding wall (hereinafter referred to as γ shield) 4
The self-propelled inspection device (hereinafter referred to as automatic device) 5 is supported during periodic inspections and the like. The track 3 of the above conventional example has an integral structure as shown in Japanese Patent Application Laid-Open No. 57-166558 "Track for Running on the Surface of Nuclear Reactor Pressure Vessel", and is mounted in a suspended manner by supporting the vicinity of its upper end. configured to allow thermal expansion and contraction to escape;
ing.

FIG. 9 shows a developed view of the body portion of the reactor vessel 1. As shown in FIG.

Since the yX sub-reactor pressure vessel is very large, it is manufactured by bending and welding steel plates, and welding line 6 in the circumferential direction and welding line #! in the longitudinal direction. 7.

Said track 3 is installed to guide the automatic device along this welding line 6,7.

FIG. 10 shows an automatic device 5 running along a circumferential track 3.
The perspective view of FIG. 11 shows the development of the above-mentioned track 3.

The track 3 consists of a vertical track 3.1 and a circumferential track 3.2, which are installed along weld lines 6 and 7, respectively.

In addition, the vertical track 3.1 and the circumferential track 3.2 are the turntable 3.
3, and the automatic device 5 attached to the end A of the vertical tracks 3 and 1 can be transferred to the circumferential tracks 3 and 2 using the turntable and travel around the entire circumference.

Conventionally, as described above, a track device has been used in which vertical and circumferential tracks are connected and the track 3 has an integral structure.

It is expected that in the 1980s, as large-scale forging technology progressed, nuclear reactor pressure vessels would be manufactured using integrally forged rings (shell rings).

In this case, there is no vertical weld line in the body of the reactor pressure vessel 1', as shown in FIG. 12, and there is only a circumferential weld line 6.

If the purpose is simply to guide the automatic device along the inspection target (circumferential weld line), it is sufficient to provide only the circumferential tracks 3 and 2 as shown in FIG. 13.

Figure 14 shows a known circumferential orbit (Japanese Unexamined Patent Publication No. 57-166558
In this horizontal cross-sectional view showing the supported state of the model No. 1, an integral ring-shaped circumferential track 10 is supported on a support skirt 14 by a plurality of (eight in this example) one-bar links 13.

Both ends 11° and 12 of the above-mentioned one-bar link are circumferential orbits 1 and 12, respectively.
0. It is pivoted to the support skirt 14 so as to be rotatable in a horizontal plane.

In Figure 15, the orbit of ・ at room temperature is shown by the solid line 10.1.

FIG. 4 is an action explanatory diagram in which circumferential orbits during temperature rise are shown by chain lines 10 and 2, respectively.

Due to thermal expansion due to temperature rise, the circumferential orbit 10 and the one-section link 13
The axial fulcrum of the shaft moves from 11.1 to 11.2, thereby absorbing the thermal expansion of the circumferential orbit 10 and preventing the generation of excessive thermal stress.

However, the circumferential orbit 10 with the structure described above (Fig. 7)
In this case, the orbit 10 must have sufficient rigidity and be continuous, so in order to install automatic equipment, an inspector must approach at least one location on the orbit 10 and perform the installation work. .

Since it is highly undesirable for inspectors to approach the area near the core area where the radiation dose is high, it is necessary to install automated equipment on the track, especially at a location far away from the core area.

The above-mentioned known example (JP-A-57-166558) (No. 11
According to Figure), the radiation dose for inspectors is low and it is possible to inspect the circumferential weld line all around the circumference, but if there is no vertical weld line, the vertical track is installed only for the purpose of automatic equipment transferring to the circumferential track. This results in high costs.

Furthermore, an integrated track (vertical/circumferential track connection) requires more time to install and adjust than a case of only a circumferential track.

The known example shown in FIG. 14 (Japanese Unexamined Patent Publication No. 58-92858) is good in terms of installation and C05T, but when used in a place with a high radiation dose, the radiation dose to the inspector increases.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances.

It is possible to install a circumferential orbit in such a way that it will not be subject to excessive thermal stress, and furthermore, even without providing a vertical track, an automatic device can be safely advanced to the circumferential orbit, and the automatic device can be safely recovered. The purpose of this project is to provide an inspection trajectory that can be obtained.

[Summary of the invention]

In order to achieve the above objects, 1. The track of the present invention is an inspection track that is attached around a pressure vessel and guides a self-propelled automatic inspection device, in which a part of the annular track surrounding the pressure vessel is divided. and are connected so as to be openable and closable, fixedly supporting both ends of the remaining divided tracks, and horizontally guiding a plurality of locations other than the fixed support portions at both ends. It is characterized by providing means for supporting the weight.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described with reference to FIGS. 1 to 5 in sequence.

FIG. 1 is a horizontal cross-sectional view of one embodiment of the present invention, in which a circumferential orbit 20 is a reactor pressure vessel 1 and a heat insulating material 2.
It is installed between the two, and has a ring shape as a whole.

One small portion 21 of the annular portion is divided and hinged with a hinge 21a to form the opening/closing portion 21. 21 drawn with a solid line is the closed position, 21' drawn with a chain line is the open position,
are shown respectively.

At the free end side of the opening/closing section 21 configured as described above.

A guide track 24 is connected by a fulcrum shaft 23 .

A guide track 24 drawn with a solid line indicates the position when the above-mentioned opening/closing part 21 is closed, and 24' drawn with a chain line indicates the position when the opening/closing part 21 is opened.

By moving the guide track 24 to 24'.

The opening/closing part 21 opens in the direction of arrow B and becomes 21'.

The guide track 24 is at least γ in the extended state 24'.
It is desirable to penetrate through the opening 4a of the shield 4.

FIG. 2 shows the vicinity of the opening/closing section 21.

The circumferential orbit 20 becomes discontinuous when the opening/closing part 21' is open, but in order to prevent rigidity deterioration and positional deviation between the circumferential orbit 20 and the opening/closing part 21, the remaining opening/closing part 21 is divided from the annular orbit 20. (i.e., the part facing the opening/closing part 21) with the bracket 2 against the γ shield 4.
6.27 to be fixedly supported.

By fixedly supporting the above-mentioned portions with brackets 26 and 27, the annular circumferential track 20 thermally expands and contracts as shown in FIG.

Since the circumferential track 20 is fixed by brackets 26 and 27, it becomes 20' when thermally expanded. At this time, each point on the circumferential orbit 20 moves in a radial direction within a horizontal plane centered on one point 28. That is, point 29 moves in the direction of arrow 3o and becomes 31. Along with this, 1, for example, 29' is the arrow 30.
' to point 31'.

When the circumferential orbit 20 thermally expands, excessive thermal stress will not occur unless the movement is prevented.

Note that the movement amount AQ from one point 29 to 31 can be obtained from the following formula, assuming that the circumferential orbit diameter φ, the thermal expansion coefficient α, and the thermal fluctuation amount JT.

11=αφΔT A specific example of the circumferential orbit support portion 35 is shown in FIG.

This support part has four pins 32.1, 32.2, 32.3.
, 32.4 and four connecting rods 33.1 to 33.4, one end of which is connected to the circumferential track 20 and the other end of which is connected to the bracket 34.
It is fixed to the γ shield via. The pin 32-3 serves as a fixed point, and the pin 32-1 can move freely in the horizontal plane, but is restrained from moving in the vertical direction, so it supports the weight of the circumferential track 20.

FIG. 5 is a horizontal cross-sectional view showing a state in which eight sets of the support portions 35 shown in FIG. 4 are provided to support the circumferential track 20.

A circumferential orbit (indicated by a solid line) 20 at room temperature is supported concentrically with respect to the reactor pressure vessel 1 .

A part of this circumferential orbit 20 is provided with the opening/closing part 21 (this fifth part).
There is a discontinuous part 25 with a discontinuous part 25 (not shown in the figure), and both ends of the discontinuous part 25 are connected to the γ shield 4 by brackets 26 and 27.
Fixed. At a point 36 facing the discontinuous portion 25, a support portion 3 having a function of guiding the circumferential orbit 2o in the radial direction
5 is provided. A plurality of support parts 35 are horizontally attached to parts of the circumferential track 20 other than those mentioned above so as to restrict movement in the vertical direction and receive one weight.

When the circumferential orbit 2o thermally expands and becomes 20', the support part 3
5 moves as shown at 35' to absorb thermal deformation.

Another embodiment is shown in FIG.

The structure of the circumferential track 20, fixation by brackets 26, 27, etc. are the same as in the previous embodiment, but the structure of the movable support part is different.

A plurality of guide bars 40 are fixed to the γ shield 4 around the circumferential orbit 20.

The guide bars 40 are all arranged radially around the center point 28 of the discontinuous portion provided on the circumferential track 20.

A connected state of the guide bar 40 and the circumferential track 2Q is shown in FIG. 7. A side plate 41 is fixed to the circumferential track 20 via a base plate 46. As shown in FIG. The side plate 41 has rollers 42, 43, pins 44.
It is rotatably supported by 45. rollers 42, 4
3 are arranged to sandwich the guide bar 40.

Due to the rotation of the rollers 42 and 43, the side plate 41 slides only in the longitudinal direction of the guide par 40, and has sufficient rigidity against other movements.

If the circumferential orbit 20 is supported with the above structure, thermal expansion will be absorbed and position reproducibility will be good, as in the previous embodiment.

The structure is strong against external forces such as earthquakes.

In the inspection orbit configured as described above, as is clear from FIG. 2, the automatic device 5 ( Omitted in this Figure 2.

(shown in Figure 10) can be sent in and recovered, and there is no risk of workers being exposed to high radioactivity.

〔Effect of the invention〕

As detailed above, by applying the inspection track of the present invention, it is possible to install a circumferential track without the risk of receiving excessive thermal stress, and moreover, automatic equipment can be installed without providing a vertical track. It has the excellent effect of allowing the automatic device to enter orbit safely and recover it safely, and it supports the improvement of the welded structure of nuclear reactor pressure vessels, making a great contribution to its progress.

[Brief explanation of drawings]

Fig. 1 is a horizontal sectional view of a reactor pressure vessel equipped with an example of the inspection track of the present invention, Fig. 2 is a perspective view of the opening/closing part of the above embodiment, and Fig. 3 is thermal expansion and contraction in the above embodiment. FIG. 4 is a perspective view of the support section, and FIG. 5 is an explanatory diagram of the operation of the support section. FIG. 6 is a horizontal sectional view of an embodiment different from the above, and FIG.
The figure is a perspective view of the support part of the embodiment of FIG. 6. FIG. 8 is a perspective view showing an example of a known trajectory, FIG. 9 is an exploded view of a reactor pressure vessel, FIG. 10 is a perspective view of an example of automatic equipment running on the above-mentioned trajectory, and FIG. Figure 8 shows a developed view of the trajectory, Figure 12 shows a developed view of the integrally forged ring type reactor pressure vessel, and Figure 13 shows an example of the trajectory necessary for inspection of the integrally forged ring type reactor pressure vessel. Figure, 1st
Figure 4 is an explanatory diagram of a known integrated ring-shaped track support structure;
FIG. 15 is also an explanatory diagram of the operation. DESCRIPTION OF SYMBOLS 1... Reactor pressure vessel, 2... Heat insulation material, 3... Orbit, 4... γ shield, 5... Automatic device, 6...
Circumferential welding line, 7... Vertical welding line, 3... Vertical track, 3
・2... Orbit, 3.3... Turntable, 10
... circumferential orbit, 11.12 ... end (support point), 13
...-knot link, 14...support skirt, 10.1
... Circumferential orbit, 10・2... Circumferential orbit (during thermal expansion), 1
3.1...-section link, 13.2...-section link (
during thermal expansion), 11・1, 11・2...support point, 20・
...circumferential orbit, 21.21'...opening/closing part, 22...fulcrum, 23...fulcrum, 24.24'...guide track, 2
5... Discontinuous part, 26° 27... Bracket, 28
...center point, 29...point, 30...arrow, 31.
...Point, 32.1-4...Pin, 33.1-4.Connecting rod, 34.Bracket, 35.Support part, 35'
...Support part (during thermal expansion), 36...Opposing point, 40.
・Guide bar, 41...Side plate, 42.43...Roller, 44.45...Bin.

Claims (1)

[Claims] 1. In an inspection track installed around a pressure vessel to guide a self-propelled automatic inspection device, a part of the annular track surrounding the pressure vessel is divided and connected in an openable and closable manner, and the above-mentioned It is characterized by providing means for fixedly supporting both ends of most of the remaining divided track, and for supporting the weight of a plurality of parts other than the fixed support portions at both ends while guiding them in the horizontal direction. Track for inspection of pressure vessels.