JP3570462B2 - Penetration inspection adapter for J welds - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a penetrant inspection device, and more particularly, to an inspection adapter for a J weld between a CRD housing and a stub tube when a CRD is replaced.
[0002]
[Prior art]
For example, as shown in FIG. 3, a hollow CRD housing 3 penetrates a through-hole 2 provided in a lower mirror 1 of the reactor pressure vessel and extends upward in the reactor pressure vessel. It is welded to the upper surface of the stub tube 4 which is welded to the upper surface of the mirror 1. Further, a CRD 5 (Control Rod Drive: control rod driving mechanism) penetrates through the CRD housing 3 to drive a control rod in the reactor pressure vessel.
[0003]
In such a reactor pressure vessel, the CRD housing 3 may be replaced. In this case, the CRD housing 3 and the stub tube 4 are cut and removed while the CRD 5 is removed, and the welded portion 4a is cut and polished. It is necessary to weld the new CRD housing 3 and the stub tube 4 after overlay welding on the polished surface of the lever.
In this case, after overlay welding on the polished surface of the lower mirror 1 and after welding of a new stub tube 4, it is necessary to inspect the welded portion 4a for damage by penetrant inspection. However, since the inspection site is extremely narrow and inaccessible to humans, there has been a demand for a device for performing this penetrant inspection by remote control.
[0004]
FIG. 4 is an overall configuration diagram of a penetrant inspection device created by the present applicant to satisfy such a demand. This device comprises a support frame 7 suspended by a suspending means (for example, a wire rope 7a) so as to be able to ascend and descend inside the seal pipe 6, and an adapter mounting plate rotatably mounted below the support frame 7. 9, and various penetrant inspection adapters 10 (PT adapters) are mounted on the lower surface of the adapter mounting plate 9. Further, a control unit 13 (CCU) is built in the support frame 7 to supply and control a necessary power supply to the PT adapter 10.
[0005]
With the above-described configuration, the inspection location is set to an aerial environment by the seal pipe 6, the support frame 7 is suspended in the seal pipe 6, the PT adapter 10 is positioned at a predetermined position, and the PT adapter 10 of the penetrant detection device is remotely operated. Can perform various tests.
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional penetrant inspection apparatus, it is necessary to replace equipment (injection nozzle and camera) used in the four steps of cleaning, drying, penetrating liquid application, and observation for each operation. It is necessary to collect the device from the seal pipe, and it takes about 30 minutes to collect, exchange, reinsert, and set up the device. Further, there is a problem that the operation cable connected to the connector is wound up and rewinded at the time of collection and insertion, so that the cable is burdened.
[0007]
In particular, part B shown in FIG. 5 is a J weld between the CRD housing 3 and the stub tube 4. Since a part of the CRD housing 3 protrudes upward, it is avoided in a very narrow space. It is necessary to wash, dry, apply a penetrant, and observe the J weld.
[0008]
The present invention has been made to solve such a problem. That is, the object of the present invention is to perform the four steps of cleaning, drying, application of the penetrant, and observation of the J-welded portion B shown in FIG. 5 without changing the apparatus, thereby shortening the inspection work time. It is another object of the present invention to provide an inspection adapter for a penetrant inspection device capable of reducing the burden on an operation cable.
[0009]
[Means for Solving the Problems]
According to the present invention, a support frame suspended by a suspending means so as to be able to ascend and descend in a seal pipe, a control unit built in the support frame, and a pivotally mounted lower portion of the support frame. A penetrating inspection adapter for a J-weld portion having an adapter mounting plate, wherein the inspection adapter is inserted into a central hole of a CRD housing that is welded to a through hole of a lower mirror and protrudes inside to form a seal pipe. A lower end supporting portion positioned concentrically, a turning frame attached to the lower surface of the adapter mounting plate, a guide rod extending from the turning frame to the lower end supporting portion concentrically with the seal pipe, and an elevating member moving up and down along the guide rod; An extension member attached to the outer periphery of the elevating member and extending downward between the seal pipe and the CRD housing; and a permeate injection nozzle attached to the lower end of the extension member A permeation device for a J-welded part, comprising a washing water injection nozzle, a dry air injection nozzle, and an observation camera, and further comprising a water absorption nozzle expansion / contraction device attached to the extension member to extend and contract the water absorption nozzle downward. A flaw detection adapter is provided.
[0010]
According to the configuration of the present invention, the extension member is attached to the outer peripheral portion of the elevating member that moves up and down along the guide rod, the extension member extends downward between the seal pipe and the CRD housing, and the lower end thereof has the permeating liquid. With the injection nozzle, washing water injection nozzle, dry air injection nozzle, and observation camera installed, position each equipment at the optimum height near the J weld through the narrow gap between the seal pipe and the CRD housing. Can be. By turning the turning frame in this state, the J-welded portion can be washed, dried, applied with the permeating liquid, and observed by the nozzles at the lower end of the extension member and the observation camera. Further, since the water-absorbing nozzle can be extended further downward by the water-absorbing nozzle expansion / contraction device, excess water accumulated between the seal pipe and the CRD housing can be removed by absorbing water with the water-absorbing nozzle.
[0011]
Therefore, each step can be performed sequentially without replacing the apparatus, thereby shortening the inspection work time of the J-welded portion and reducing the load on the operation cable.
[0012]
According to a preferred embodiment of the present invention, the water-absorbing nozzle extending / contracting device includes a pneumatic cylinder attached to the extension member for extending and retracting the water-absorbing nozzle downward, and a guide rod for vertically guiding the water-absorbing nozzle.
With this configuration, the water absorption nozzle can be easily extended between the seal pipe and the CRD housing by the expansion and contraction of the pneumatic cylinder, so that it is positioned in accordance with the height of the gap and efficiently absorbs excess water accumulated in the gap. Can be removed.
[0013]
The motor further includes an elevating motor mounted on the revolving frame, and a ball screw rotated about a vertical axis by the elevating motor. The elevating member is moved up and down by rotation of the ball screw. With this configuration, the lifting member can be raised and lowered with high accuracy, and the height of each inspection device can be accurately positioned at the J weld.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the drawings, common portions are denoted by the same reference numerals, and redundant description is omitted.
FIG. 1 is an overall configuration diagram of a penetrant inspection apparatus to which a penetrant inspection adapter 10 for a J weld according to the present invention is attached, and FIG. 2 is a side view of the inspection adapter 10 at different scales. The inspection adapter 10 shown in FIGS. 1 and 2 uses the J weld portion B between the CRD housing 3 and the stub tube 4 shown in FIG.
[0015]
As shown in FIG. 1, the penetrant inspection device is suspended by suspending means (for example, a wire rope 7 a), and is supported by a support frame 7 which can move up and down in the seal pipe 6. A control unit 20 and an adapter mounting plate 9 pivotally mounted below the support frame 7. The penetrating inspection apparatus further includes a turning motor 16a mounted on the support frame 7, and a gear train (swing gear 16b) driven by the turning motor 16a, and an adapter mounted by the turning motor 16a via the turning gear 16b. The plate 9 is turned around a vertical center axis Z-Z.
[0016]
As shown in FIGS. 1 and 2, the inspection adapter 10 includes a lower end support 21, a turning frame 22, a guide rod 23, a lifting member 24, an extension member 25, and a plurality of inspection devices 28.
The lower end support portion 21 is inserted into the center hole of the CRD housing 3 which is welded to the through hole 2 of the lower mirror 1 and protrudes inside, and positions the position concentrically with the seal pipe 6. The revolving frame 22 is mounted on the lower surface of the adapter mounting plate 9 and revolves around a vertical center axis Z-Z by a revolving motor 16a. The guide rod 23 extends from the turning frame 22 to the lower end support 21 concentrically with the seal pipe 6. The elevating member 24 moves up and down along the guide rod 23. The extension member 25 is attached to the outer periphery of the elevating member 24 and extends downward between the seal pipe 6 and the CRD housing 3. The plurality of inspection devices 28 are attached to the lower end of the extension member 25.
[0017]
Further, the inspection adapter 10 includes a lifting motor 18a attached to the revolving frame 22, and a ball screw 18b rotated about a vertical axis by the lifting motor 18a, and the lifting member 24 is raised and lowered by rotation of the ball screw 18b. With this configuration, the elevating member 24 can be raised and lowered with high accuracy, and the height of each inspection device 28 can be accurately positioned at a predetermined inspection position.
[0018]
As shown in FIG. 1 and FIG. 2, the inspection device 28 is a permeate injection nozzle 28a, a washing water injection nozzle 28b, a dry air injection nozzle 28c, a water absorption nozzle 28d, and an observation camera 28e. The nozzle 28a, the washing water injection nozzle 28b, the dry air injection nozzle 28c, and the observation camera 28e are directly attached to the lower end of the extension member 25.
[0019]
Furthermore, a water-absorbing-nozzle expansion / contraction device 29 attached to the extension member 25 and extending and contracting the water-absorbing nozzle 28d downward is provided. The water-absorbing nozzle expansion / contraction device 29 includes a pneumatic cylinder 29a attached to the extension member 25 and extending and retracting the water-absorbing nozzle 28d downward, and a guide rod 29b for vertically guiding the water-absorbing nozzle 28d.
[0020]
With the configuration of the present invention described above, each device 28 can be positioned at an optimum height close to the J welded portion B through a narrow gap between the seal pipe 6 and the CRD housing 3. By turning the turning frame 22 in this state, the nozzles 28a to 28d at the lower end of the extension member and the observation camera 28e can wash, dry, apply a permeate, and observe the J welded portion B. In particular, since the water absorption nozzle 28d can be further extended downward by the water absorption nozzle expansion / contraction device 29, it can be positioned in accordance with the height of the gap and efficiently absorb and remove excess water accumulated between the seal pipe and the CRD housing.
[0021]
Therefore, each step can be performed sequentially without replacing the device, thereby shortening the inspection work time for the J welded portion and reducing the load on the operation cable.
[0022]
It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the spirit of the present invention.
[0023]
【The invention's effect】
As described above, the penetrant inspection adapter for a J weld according to the present invention can perform the four steps of cleaning, drying, application of a penetrant, and observation of the J weld without replacing the apparatus. Accordingly, the present invention has an excellent effect that the inspection work time can be reduced and the burden on the operation cable can be reduced.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a penetrant inspection apparatus provided with a penetrant inspection adapter for a J weld according to the present invention.
FIG. 2 is a side view of the inspection adapter of FIG.
FIG. 3 is a longitudinal sectional view of a lower mirror portion of the reactor pressure vessel.
FIG. 4 is an overall configuration diagram of a penetration testing device provided with a conventional inspection adapter.
FIG. 5 is a longitudinal sectional view of a lower mirror portion having a J-welded portion to which the present invention is applied.
[Explanation of symbols]
1 lower mirror 2 through hole 3 CRD housing 4 stub tube 5 CRD
6 Seal pipe 7 Support frame 9 Adapter mounting plate 10 Penetration inspection adapter (PT adapter)
11 Bore plug 12 Lifting shaft 13 Control unit (CCU)
13a connector 13b cable 16 turning device 16a turning motor 16b gear train (turning gear)
18 Elevating device 18a Elevating motor 18b Ball screw 20 Control unit 21 Lower end support part 22 Revolving frame 23 Guide rod 24 Elevating member 25 Extension member 28 Inspector 28a Penetrant injection nozzle 28b Wash water injection nozzle 28c Dry air injection nozzle 28d Water absorption nozzle 28e Observation Camera (CCD)
29 Water-absorbing nozzle telescopic device 29a Pneumatic cylinder 29b Guide rod

Claims (3)

A support frame suspended by the suspending means so as to be able to move up and down in the seal pipe, a control unit built in the support frame, and an adapter mounting plate pivotally attached to a lower portion of the support frame. A penetrant inspection adapter for J welds provided with
The inspection adapter includes a lower end support portion which is inserted into a central hole of the CRD housing which is welded to a through hole of the lower mirror and protrudes inside and is positioned concentrically with the seal pipe, a revolving frame attached to the lower surface of the adapter attachment plate. A guide rod extending from the revolving frame to the lower end support portion concentrically with the seal pipe, an elevating member elevating and lowering along the guide rod, and extending downward between the seal pipe and the CRD housing attached to an outer peripheral portion of the elevating member. An extension member, comprising a permeate injection nozzle, a washing water injection nozzle, a dry air injection nozzle, and an observation camera attached to the lower end of the extension member,
Further, a penetrating inspection adapter for a J-welded part, further comprising a water-absorbing-nozzle extending / contracting device attached to the extension member and extending and retracting the water-absorbing nozzle downward. The J-welding according to claim 1, wherein the water-absorbing nozzle expansion / contraction device comprises a pneumatic cylinder attached to an extension member and extending and retracting the water-absorbing nozzle downward, and a guide rod for vertically guiding the water-absorbing nozzle. Penetrant inspection adapter for parts. 2. The J according to claim 1, further comprising an elevating motor mounted on a revolving frame, and a ball screw rotated by a vertical motor by the elevating motor, wherein the elevating member is elevated by rotation of the ball screw. 3. Penetration inspection adapter for welds.

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