JPH07110320A - Pressure vessel tester - Google Patents

Abstract

PURPOSE:To provide a pressure vessel tester with which an ISI(inservice inspection) of the area of a pressure vessel furnace core of a BWR plant (pressurized water reactor) can be carried out easily and accurately. CONSTITUTION:A drive mechanism is provided together with a carriage drive source 21 and mast drive sources 22 and 23. Also provided are a self-travelling carriage which moves along the circumferential direction on upper end faces of a circular member of a pressure vessel 1 itself of a BWR plant or other circular members (e.g. a ring gutter 13 installed on a main flange part 12) of the pressure vessel itself, masts 16 and 18 which are supported by the carriage while being made free to extend in the vertical way of the pressure vessel 1, an arm 19 which is provided at the lower end part of the mast 18 while being allowed to slide horizontally and a sensor 20 which is provided at the lower end part of the arm 19 to inspect the pressure vessel from the internal side of the pressure vessel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection device for a pressure vessel, and more particularly to an inspection device suitable for inspecting a reactor pressure vessel during its service period from the inside of the reactor pressure vessel.

[0002]

2. Description of the Related Art Reactors for power generation are inspected once a year (In-Service Inspection,
Hereafter, this is abbreviated as "ISI")
Reactor Pressure Vessel (Reactor Pressure)
Vessel (hereinafter, abbreviated as “RPV”) and the like require inspection of pressure-resistant welded portions.

The purpose of carrying out ISI is to periodically confirm that the pressure-resistant portion such as RPV is not defective, is sound, and is not likely to be damaged during the service life (or life) of the reactor. It is in. In terms of RPV, since the neutron irradiation embrittlement of the steel material is expected in the portion close to the core, it is a particularly important portion from the viewpoint of soundness confirmation by ISI.

For this reason, a boiling water nuclear power plant (Boiling Water Rea) that has been constructed in recent years is used.
ctor (hereinafter, abbreviated as "BWR plant"), as shown in FIGS. 14 and 15, the inner diameter of the biological shield 2 is slightly larger than the outer diameter of the RPV 1, and the RPV 1 and the heat insulating material 3 are used. Provide an appropriate gap 4 between
The inspection device is installed and moved in this gap 4, and the RPV1
The plant is designed and manufactured in consideration of being able to carry out the ISI from the outside of the RPV.

However, in the old plant designed and manufactured before the periodic inspection is obliged, the ISI implementation from the outer surface of the RPV, which has been performed in recent years, is not taken into consideration. However, since the heat insulating material 3 is narrow and the heat insulating material 3 is not removable, it is substantially difficult to perform ISI from the outer surface side of the RPV.

Therefore, in the case of such an old plant, it is possible to carry out the ISI from the inside of the RPV. In fact, due to structural restrictions, it is impossible to carry out ISI from the outside of the RPV, which is a pressurized water nuclear power plant (Pressurized Water Rea).
Ctor, hereinafter abbreviated as "PWR plant") R
In PV, ISI is usually carried out in water from the inner surface of the RPV, and a device for such ISI has been devised and put into practical use.

[0007]

However, the BWR
In the case of, the ISI implementation from the inner surface side of the RPV is not so easy as in PWR. That is, in the case of PWR, it is possible to remove the reactor internals inside the RPV to the outside of the RPV during ISI. Therefore, since there are no obstacles for implementing ISI in the furnace, it is easy to access the inner wall of the RPV from the inside of the furnace.

On the other hand, in the case of BWR, FIGS.
As shown in, the shroud 5, which is a permanent facility, is installed in the furnace.
Since the upper shroud 6, the feed water sparger 7, the core spray inner tube 8, the shroud head bolt lug 9 and the like are present, in order to approach the inner wall of the RPV core region in the vicinity of the core 10, avoid these internal structures while approaching. There is a need to.

Particularly, the gap d is extremely small, about 10 cm, and the gap e between the RPV 1 and the shroud 5 is also small. Therefore, in the large-sized PWR and RPV equipment, due to dimensional restrictions, the inner wall of the BWR and RPV core regions is restricted. Approach the IS
I can't do it. For this reason, avoiding the in-core structure, approaching the inner wall of the RPV core region,
The advent of a device capable of performing I is highly desired.

As described above, the object of the present invention is to realize the conventional I
An object of the present invention is to provide a pressure vessel inspection device capable of easily and appropriately performing RPV of an old BWR plant, which has been difficult to perform SI, and particularly ISI of the RPV core.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a carriage drive source and its drive mechanism and a mast drive source and its drive mechanism, and to be movable on the upper end surface of an annular member of a pressure vessel in the circumferential direction. A self-propelled carriage, a mast that is supported by the carriage and is expandable and contractible in the vertical direction of the pressure vessel, an arm that is provided at the lower end of the mast and is horizontally slidable, and a tip of the arm. And a sensor for inspecting the pressure container from the inner surface side of the pressure container, and a pressure container inspection device.

[0012]

Using the annular member of the pressure vessel as a track, the upper end surface of the carriage is self-propelled in a monorail system by the carriage drive source and drive mechanism. This carriage uses a mounted mast drive source and its drive mechanism to expand and contract the mast in the vertical direction, and the arm provided at the lower end of the mast slides horizontally, with a sensor provided at the tip of the mast. Inspect the inner surface of the pressure vessel in place.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of the present invention,
This pressure vessel inspection device includes a ring gutter 13 installed on the main flange 12 of the reactor pressure vessel 1, a carriage 14 that moves along the ring gutter 13, and a mast guide 15 attached to the carriage 14. , The upper mast 1 guided in the core by this mast guide 15
6 and an upper mast reinforcement 17 for reinforcing the upper mast 16 and a lower mast 18 connected to the upper mast 16.
An arm 19 movably supported by the lower mast 18 and a head 20 attached to one end of the arm 19 are main components.

The ring gutter 13 is installed along the main flange 12 of the reactor pressure vessel 1 and has sufficient strength to support the total weight of the carriage 14 and the upper mast 15 and the like. A carriage 14 is installed so as to be movable along the carriage 14.

As shown in FIGS. 1 and 2, the carriage 14 is provided with a top plate 14A and an arc-shaped carriage side plate 14B, and a carriage drive source 21 is provided on the top plate 14A. Wheels (not shown) installed on the bottom side of 14A are driven so that the carriage 14 can travel along the ring gutter 13.

A pair of upper mast drive sources 22 are installed adjacent to the carriage drive source 21, and each upper mast drive source 22 has a pinion A27, and each pinion A meshes with a rack A31 of the upper mast 16. ing. With this rack and pinion mechanism, the upper mast 1
6 and the upper mast reinforcement are moved up and down in the vertical direction of the RPV 1. In addition, the top plate 14 of the carriage 14
A pair of hinge flanges 28 is attached to A.

As shown in FIG. 3, rollers A29 are provided at the four corners of the mast guide 15, and piston brackets 30 are provided at the lower ends of the side surfaces of the mast guide 15, respectively.
As shown in FIG. 3 (B), a mast tilt adjusting mechanism section 24 for moving in the arrow direction is installed. The piston bracket 30 is pivotally attached to the pin bracket 26 installed on the carriage side plate 14B. Also mast guide 1
A protrusion 15A is formed on each of the upper end surfaces of the side faces of the carriage 5, and the protrusion 15A is pivotally supported by a hinge bracket 28 provided on the top plate 14A of the carriage.

As shown in FIG. 4, the upper mast 16 is provided with an upper mast reinforcing member 17 for increasing the deformation rigidity of the upper mast itself, and a rail 32 installed along the side surface of the upper mast reinforcing member 17. The roller A29 shown in FIG. 3 is engaged. The upper mast 16 is formed in a pipe shape, and the lower mast 18 movably inserted into the upper mast 16 is moved by the lower mast drive source 23 in the vertical direction of the RPV 1.

An arm drive source 25 is installed at the lower end of the lower mast 18 as shown in FIGS. 5 and 6, and a pinion B34 driven by the arm drive source 25 is provided. A rack B35 is formed along the longitudinal direction of each of the two arms 19 formed in an arc shape, and the pinion B34 is a rack B3 formed on the arm 19.
It meshes with 5. Grooves are formed on both end surfaces of the arm 19 in the vertical direction along the longitudinal direction, and the rollers 33 are engaged with the grooves. Further, a head 20 fixed to both ends of the arm 19 in the longitudinal direction is provided with a sensor assembly 36 having a plurality of ultrasonic probes, television cameras or the like.

Next, the operation of the pressure vessel inspection device configured as described above will be described. 7 and 8 show an example of how the inspection apparatus according to the present invention approaches the RPV core region and the operation of each part.

In FIG. 7A, the carriage drive source 21 installed on the carriage 14 is driven to drive the carriage 1
4 runs along the ring gutter 13 and stops at a predetermined position. At this time, the lower mast 18 is housed in the upper mast 16, and the upper mast 16 and the upper mast reinforcing plate 17 are
Is located above the mast guide 15.

After the carriage 14 stops at a predetermined position of the ring gutter 13, the upper mast drive source 22 is maintained with the verticality of the upper mast 16 maintained as shown in FIG. 7B.
When the pinion A27 of the mast drive source 22 rotates, the upper mast 16 having the rack A31 meshing with the pinion A27 vertically descends along with the upper mast reinforcement 17 along the inner surface of the core of the RPV 1.

By lowering the upper mast 16, the upper mast 1
The lowering of the upper mast 16 stops when the arm 19 installed at the lower end of the lower mast 18 housed in 6 is close to above the water supply sparger 7.

Next, the piston bracket 30 is extended to the RPV1 side by driving the mast tilt adjusting mechanism 24 installed on the mast guide 15, and the mast guide 15 is fixed to the RPV1 with the projection 15A pivotally supported by the hinge bracket 28 as a base point. Inclines toward the center. This mast guide 15
As shown in FIG. 7 (C), the upper mast 16
Lower mast 1 which is tilted and is housed in upper mast 16
The arm 19 installed at the lower end of the water supply sparger 7
The water supply sparger 7 stops at an upper position at a distance.

In this way, the mast drive source 22 is driven with the mast tilt angle maintained, and the mast drive source 22 is housed in the upper mast 16 again by the mechanism of the rack A31 and the pinion A27 as shown in FIG. 8 (A). The arm 19 installed at the lower end of the lower mast 18 stops descending when it is located above the upper shroud 6.

Next, as shown in FIG. 8 (B), the upper mast 16 is maintained in the vertical state again by driving the mast tilt adjusting mechanism 24 installed in the mast guide 15. In this state, as shown in FIG. 8C, the lower mast drive source 23 is driven, the lower mast 18 accommodated in the upper mast 16 vertically descends, and the arm 19 installed at the lower end of the lower mast 18 is moved. Stops at a predetermined gap to be inspected between the outer peripheral surface of the shroud 5 and the inner peripheral surface of the RPV 1.

By the operation shown in FIGS. 7 and 8, the inspection apparatus can be guided to a predetermined position while avoiding the water supply sparger or the like which becomes an obstacle.

9 to 11 show an example of the operation of the arm 19. In FIG. 9, the arm 19 and the outer peripheral surface of the shroud 5 and the RP are shown.
It shows a state when the vehicle stops at a predetermined gap to be inspected from the inner peripheral surface of V1. FIG. 12 is a sectional view showing the situation when the arm is stopped, and the arm drive source 25 and the head 20 are located in the space between the shroud head bolt lugs 9. Therefore, in FIG. 7 (A) described above,
Run the carriage 14 along the ring gutter 14,
When adjusting the position of the carriage 14, the arm drive source 25 and the head 20 are adjusted to positions such that they can pass through the space between the shroud head bolt lugs 9.

After the arm 19 is stopped at a predetermined position, the pinion B34 is rotated by the driving of the arm drive source 25, and the two arms 19 having the rack B35 which meshes with the pinion B34 as shown in FIG. The heads 20 which are driven in mutually opposite directions and fixed to one end side of the arcuate arm 19 move along the inner surface of the RPV 1 and can perform ultrasonic flaw detection and the like in the RPV core region.

Next, as shown in FIG. 11, the arm drive source 2
5 drives the pinion B34 to rotate in the direction opposite to that in FIG. 10, the two arms 19 are driven in opposite directions, and the sensor assembly 3 installed on the head 20 is rotated.
6 moves along the inner surface of RPV1.

One of the two sensor assemblies 36 is installed as a spare when the other sensor assembly 36 fails, but by installing the sensor assembly 36 on one end side of each of the two arms 19, You can balance left and right with respect to the lower mast 18,
Even when the lower mast 18 is thinned, the deformation of the lower mast 18 can be prevented. Further, since the arm 19 has an arc shape, the RPV 1 can be inspected even in a narrow space between the RPV 1 and the shroud 5.

FIG. 13 shows an example of the operation of the head 20.
The sensor assembly 36 in the head 20 is installed so as to be able to project from the head 20, and is housed in the head 20 as shown in FIG. 13A when the arm 19 is stopped at a predetermined position to be inspected. In this state, the arm 19 is set to a predetermined position to be inspected, and as shown in FIG.
9 is driven in the horizontal direction, and when the inspection of the RPV 1 is performed, the sensor assembly 36 projects from the head 20 as shown in FIG. With this mechanism, the distance (water distance) between the sensor assembly 36 and the inner surface of the RPV 1 can be adjusted to an optimum inspection distance.

Incidentally, the carriage 14, the upper mast 16,
Lower mast 18, arm 19, mast tilt adjusting mechanism 2
4. The mechanism for projecting the sensor assembly 36 from the head 20 can be driven by remote automatic operation, remote manual operation, or a mixed operation thereof.

In the above-mentioned embodiments, an example of the ring gutter which is integrated with the main flange portion of the pressure vessel as the annular member of the pressure vessel is shown, but the present invention is not limited to this, and the pressure is not limited to this. It may be another annular member integrated with the container or the annular member of the pressure container itself.

[0035]

As described above, according to the present invention, a carriage drive source and its drive mechanism, a mast drive source and its self-propelled carriage movable along the circumferential direction of an annular member, and its drive mechanism, A mast that is supported by the carriage and that can expand and contract in the vertical direction of the pressure vessel, an arm that is provided at the lower end of the mast and that can slide in the horizontal direction, and an arm that is provided at the tip of this arm from the inner surface of the pressure vessel. Since it is equipped with a sensor for inspecting the pressure vessel, the carriage is moved to a predetermined position along the circumferential direction and lowered from that position while avoiding an obstacle in a narrow space,
Then, by sliding the arm at a predetermined position, a sensor provided at the tip of the arm enables ultrasonic flaw detection, television observation, etc. from the inner surface side of the pressure vessel such as the RPV core region.

Utilizing the annular member of the pressure vessel as a track,
Since a carriage having a carriage driving source and a driving mechanism is self-propelled on this on a monorail system, it is not necessary to provide another structure for moving the carriage such as a gantry on the pressure vessel.
The inspection device becomes compact and other work can be performed in parallel.

Further, since the annular member of the pressure vessel whose size is originally determined is used as the track, the inspection and positioning can be easily performed in correspondence with the pressure vessel. Further, the self-propelled type has a wide range of speed adjustment of the carriage, so that the carriage can be quickly moved to a predetermined position and can be delicately moved. The mast hanging from the carriage plays the role of a balance weight of the monorail type carriage, and by controlling the expansion and contraction of the mast and the carriage self-propelling, the natural vibration of the mast can be easily adjusted to prevent steadying.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a pressure vessel inspection device of the present invention.

2A is a front view of a carriage in the pressure vessel inspection device of FIG. 1, and FIG. 2B is a plan view of FIG. 2A.

3A is a front view of a mast guide in the pressure vessel inspection device of FIG. 1, FIG. 3B is a side view of FIG. 3A, and FIG.
Is a plan view of (A)

4 (A) is a front view of a mast in the pressure vessel inspection device of FIG. 1, (B) is a side view of (A), and (C) is (A).
Top view of

5A is a front view of an arm / head in the pressure vessel of FIG. 1, and FIG. 5B is a side view showing a partial cross section of FIG.
(C) is an end view in the D direction of (A)

FIG. 6 is a cross-sectional view showing an arrangement state of the arm / head shown in FIG.

FIG. 7 is a cross-sectional view sequentially showing how the arm head approaches the core region.

FIG. 8 is a cross-sectional view sequentially showing how the arm head approaches the core region.

FIG. 9 is an explanatory diagram showing the operation of the arm.

FIG. 10 is an explanatory diagram showing the operation of the arm.

FIG. 11 is an explanatory diagram showing the operation of the arm.

FIG. 12 is a cross-sectional view showing an arrangement state of arm heads in a core region.

FIG. 13 is an explanatory view showing the operation of the sensor assembly.

FIG. 14 is a vertical sectional view showing a reactor building and RPV.

FIG. 15 is an enlarged sectional view of part A in FIG.

FIG. 16 is a vertical sectional view showing the internal structure of the BWR.

17 is a sectional view taken along line BB of FIG.

FIG. 18 is an enlarged view of part C in FIG.

[Explanation of symbols]

 1 RPV Pressure Vessel 2 Body Shield 3 Heat Insulating Material 4 Gap 5 Shroud 6 Upper Shroud 7 Water Supply Sparger 8 Core Spray Inner Tube 9 Shroud Head Bolt Lug 10 Core 11 Sparger Elbow 12 Reactor Pressure Vessel Main Flange 13 Ring Gutter 14 Carriage 15 Mast Guide 16 Upper mast 17 Upper mast reinforcement 18 Lower mast 19 Arm 20 Head 21 Carriage drive source 22 Upper mast drive source 23 Lower mast drive source 24 Mast tilt adjusting mechanism 25 Arm drive source 28 Hinge bracket 31 Rack A 32 Rail 36 Sensor assembly

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takenori Shindo 6-9 Takaracho, Kure-shi, Hiroshima Babcock Hitachi Ltd. Kure Factory (72) Masao Kubo 6-9 Takaracho, Kure-shi, Hiroshima Babcock Hitachi Ltd. Kure Factory

Claims (7)

[Claims] 1. A self-propelled carriage that includes a carriage drive source and its drive mechanism, and a mast drive source and its drive mechanism, and is movable along the circumferential direction on the upper end surface of an annular member of a pressure vessel, and this carriage. A mast that is supported by the mast and is capable of expanding and contracting in the vertical direction of the pressure vessel, and an arm that is provided at the lower end of the mast and that can slide in the horizontal direction,
A pressure vessel inspection device, comprising: a sensor provided at the tip of the arm to inspect the pressure vessel from the inner surface side of the pressure vessel. 2. The pressure vessel according to claim 1, wherein the carriage has a holding member for holding the annular member, is for traveling an upper end surface of the annular member, and has wheels for supporting the carriage. Inspection device. 3. The pressure vessel inspection device according to claim 1, wherein the carriage and the mast have a symmetrical structure with respect to a longitudinal plane including the central axis of the pressure vessel and the central axis of the mast. 4. The pressure vessel inspection device according to claim 1, wherein the arm is arcuate in a horizontal direction. 5. The pressure according to claim 1, wherein the sensor provided on the arm is provided with a mechanism capable of adjusting a distance between the sensor and a wall surface of the pressure vessel by adjusting a distance by which the sensor projects in the circumferential direction of the pressure vessel. Container inspection device. 6. The pressure vessel inspection device according to claim 1, wherein the sensor is an ultrasonic flaw detection probe or a television camera. 7. The mechanism for adjusting the distance between the carriage, the mast, the sensor and the wall surface of the pressure vessel is a mechanism capable of remote automatic operation, remote manual operation, or a mixed operation thereof. Kano pressure vessel inspection device.