JP4987388B2 - Device access device to the annulus - Google Patents

Description

The present invention relates to a device access apparatus to annulus for introducing the maintenance equipment in the annulus of the core shroud outer circumferential surface during maintenance of the improved boiling water reactor (ABWR).

  When carrying out maintenance and inspection work on the reactor internals during the period when the nuclear power plant is shut down, suspend the equipment for maintenance and inspection from the work carriage installed at the top of the well while the reactor is full. Thus, it is a normal means to approach the target site.

  By the way, for the core shroud, which is the reactor internal structure of the improved boiling water reactor, the maintenance inspection equipment is moved using a trackless traveling device designed for each inspection part, if necessary. In particular, maintenance inspections have been carried out at and near the welds.

  However, with this method, it is difficult to absolutely position the equipment for maintenance and inspection, and misalignment is likely to occur during traveling of the trackless traveling device. Complex operations such as feedback were necessary.

  Further, in the improved boiling water reactor, a plurality of internal pump guide rails are fixedly installed in the vertical direction above the internal pump (RIP) and in the annulus portion which is the outer peripheral position of the core shroud. The internal pump guide rail becomes an obstacle, making it difficult to continuously move the trackless traveling device.

Conventionally, as a method and apparatus for inspecting the annulus space of a boiling water reactor, a method of inspecting a recirculation pump in the reactor with a swimming robot (Patent Document 1), an inspection of an internal pump motor casing, etc. A support structure (Patent Document 2) for facilitating the above has been proposed.
Japanese Patent Laid-Open No. 7-209472 JP 2000-338288 A

  As described above, in the conventional technology, since the access to the annulus portion of the outer peripheral surface of the core shroud of the improved boiling water reactor can only be accessed by suspending or only partial access by a trackless traveling device, it is highly accurate. And efficient work was difficult.

The present invention has been made in view of such circumstances, and a maintenance inspection device is simply moored to an internal pump guide rail by remote control, and the entire surface of the core shroud is accurately obtained with reference to the internal pump guide rail. It is another object of the present invention to provide a device access device for an annulus portion that can be positioned close to the annulus portion.

In order to achieve the above object, according to the present invention, there is provided a device access device to an annulus portion for introducing a maintenance inspection device into an annulus portion of an improved boiling water reactor, and a device base that can be suspended in the reactor And an apparatus base attitude control mechanism for controlling the attitude of the apparatus base, and the apparatus base on the internal pump guide rail that is fixedly installed vertically above the internal pump and at the outer peripheral position of the core shroud. A device base lifting clamp mechanism that is moored so as to be adjustable, a device support arm that supports the maintenance inspection device and the auxiliary clamp device , and a device support arm lifting that supports the device support arm to the device base in a height adjustable manner. comprising a mechanism, wherein the device support arm is configured longer than the midpoint between the adjacent internal pumps guide rails, the Co clamping mechanism provides a device access device to the annulus, characterized in that to hold extends into internal pump guide rail side to the adjacent device support arm in the circumferential direction during movement.

  According to the present invention, by using the existing internal pump guide rail as a reference, it is possible to accurately position various maintenance and inspection devices on the entire surface of the core shroud and the annulus, and as a result, improved boiling Safety evaluation, repair work, etc. for the annulus part of the water reactor can be performed easily.

Hereinafter, an embodiment of an apparatus access device for an annulus section according to the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing a state in which an equipment access device 110 is suspended from an annulus portion 104 in a reactor pressure vessel 101 in an improved boiling water reactor. FIG. 2 is a cross-sectional view showing the annulus portion 104.

  As shown in FIGS. 1 and 2, an annulus portion 104 is formed between a reactor wall 102 and a core shroud 103 in a reactor pressure vessel 101 of an improved boiling water reactor. Within the 104, ten internal pumps 105 are installed at an angular interval of 36 ° in plan view. A pair of internal pump guide rails 106 are attached to the outer peripheral surface of the core shroud 103 so as to be positioned above each internal pump 105.

  When the initial internal pumps 105 are installed, these internal pumps 105 are suspended along the internal pump guide rail 106. A funnel-shaped lead-in 116 is provided at the upper end of the internal pump guide rail 106.

  After the reactor operation, at the time when the reactor is stopped and the periodic inspection is performed, all the annulus portions 104 in the reactor pressure vessel 101 are submerged, and the maintenance inspection device 1 is accessed to this part. For this purpose, it is suspended from a work cart (not shown) installed approximately 20 m above, and the target work is carried out by remote control. The equipment access device 110 according to the present embodiment is used to accurately position and scan the maintenance / inspection equipment 1 in operations such as inspection and repair around the core shroud 103.

  As shown in FIG. 1, the core shroud 103 has an upper body 112a and a lower body 112b. An upper ring 114 is provided at the upper end of the upper body 112a, and a core support plate 117 is mounted thereon. Yes. A lower ring 115 is provided between the upper cylinder 112a and the lower cylinder 112b, and a core support plate 118 is provided on the lower ring 115. Reference numeral 119 denotes a weld line (H4 weld line).

  FIG. 3 is an overall perspective view showing the configuration of the device access apparatus 110 according to the present embodiment.

  As shown in FIG. 3, the device access apparatus 110 has a vertically long thin box-shaped apparatus base 2. A suspension cable 16 is connected to the upper end of the apparatus base 2, and the suspension operation from the furnace can be performed via the cable 16.

  A device base posture control mechanism 3 for controlling the posture of the device base 2 is provided at a lower portion of one side surface of the device base 2. The apparatus base attitude control mechanism 3 has a configuration including, for example, a pair of right and left attitude control screws 12 and 12, and these attitude control screws 12 and 12 are provided in the apparatus base 2 and are not shown. The device base 2 is independently driven by a drive mechanism and its remote control device, and the device base 2 can be moved in various directions underwater by the difference between the left and right propulsive forces.

A horizontally long device support arm 14 that supports the work head 15, the auxiliary clamp mechanism 20, and the like is disposed on the upper portion of the apparatus base 2. The device support arm 14 is supported by a device support arm lifting mechanism 13 for raising / lowering driving provided on one side surface of the apparatus base 2 through a columnar lifting tool 6 so as to be movable up and down. Work head 15 is configured to support the maintenance equipment 1, it is possible to attach the tool or the like as needed as maintenance equipment 1. For example, an underwater TV camera is used for appearance inspection, an overflow flaw detection sensor is used for surface flaw detection, and an ultrasonic wave is used for inspection and defect sizing to the inside of the material. Attach a probe, etc., or a grinder or EDM electrode when repair work is performed. The auxiliary clamp mechanism 20 is applied when moving in the circumferential direction, and will be described later.

  On the other side of the apparatus base 2, an apparatus base lifting clamp mechanism 11 for mooring the apparatus base 2 to the internal pump guide rail 106 so as to be adjustable in height is provided. As described above, 10 sets of the internal pump guide rails 106 are arranged on the outer peripheral surface of the core shroud 103, and each set of the internal pump guide rails 106 is arranged at regular intervals in the circumferential direction of the core shroud 103. A pair is formed, and is fixed to the outer peripheral position of the core shroud 103 along the vertical direction. The apparatus base lifting clamp mechanism 11 can be anchored to the internal pump guide rails 106 that form a pair.

  4 and 5 are explanatory views showing the detailed configuration and operation of the apparatus base lifting clamp mechanism 11. FIG. 4 is a plan view partially showing a state in which the apparatus base lifting clamp mechanism 11 is anchored to the internal pump guide rail 106, and FIG. 5 is a side view.

  As shown in FIG. 4, a set of internal pump guide rails 106, 106 provided on the outer peripheral surface of the core shroud 103 has a substantially concave cross section, and the concave surfaces thereof face each other. Specifically, the internal pump guide rails 106 and 106 are composed of a pair of end portions that are substantially orthogonal to each other and an inclined central side portion that connects them.

  Thus, with respect to one guide rail 106 facing each other, the first apparatus base lifting clamp mechanism 11 (11a) is an integrated wheel that engages with the central side and one end side of the internal pump guide rail 106. A first clamp wheel 30 is provided. The clamp wheel 30 is supported by an arm 28 a via a shaft 29 a, and the arm 28 a is supported by a clamp cylinder 33 provided on the apparatus base 2 and can be attached to and detached from the clamp wheel 30.

  The second apparatus base lifting clamp mechanism 11 (11b) includes a clamp wheel 31 that engages with one end of the internal pump guide rail 106 and a clamp that engages with the central side of the internal pump guide rail 106. A pair of clamp wheels with wheels 32 is provided. The clamp wheels 31 and 32 are supported by an arm 28b via shafts 29b and 29c, respectively. The arm 28b is supported by a clamp cylinder 34 provided on the apparatus base 2 and can be attached to and detached from the clamp wheel 30. It has become.

  Then, as shown in FIG. 5, the first device base lifting clamp mechanism 11 (11 a) is installed in two vertical positions with different heights from the device base 2. One mechanism 11 (11b) is installed in the apparatus base 2. The second apparatus base lifting clamp mechanism 11 (11b) is disposed at an intermediate height position of the first vertically disposed apparatus base lifting clamp mechanism 11 (11a).

  Further, a limit switch 35 for setting an ascent limit is provided in the first apparatus base lifting clamp mechanism 11 (11a) which is arranged at a high position. This limit switch 35 can detect the absolute position in the vertical direction with respect to the core shroud 103 by contacting the lead-in portion 116 located above the internal pump guide rail 106 when the apparatus base 2 is raised. is there.

  FIG. 6 is an explanatory diagram showing the relationship between the distance between the internal pump guide rails 106 a, 106 b, and 106 c and the length of the device support arm 14. In order to access the work head 15 to the entire area of the core shroud 103, as shown in FIG. The length A is configured. According to this configuration, when the apparatus moves to the adjacent internal pump guide rails 106a, 106b, 106c, it is possible to ensure the overlap of the access range.

  Next, with reference to FIGS. 7A to 7D, a configuration in which various tools are simply exchanged for the work head 15 of the device support arm 14 will be described. That is, although the apparatus support arm 14 mentioned above is a fixed type, it can be slid to the left and right at the fitting portion with the apparatus support arm elevating mechanism 13, or the entire structure can be expanded and contracted by a telescopic mechanism. It is also possible to reduce the size. Furthermore, taking advantage of the feature that the annulus section 104 of the improved boiling water reactor is wide, the equipment support arm 14 can be a multi-axis control robot arm. On the other hand, it is possible to carry out complicated work from inspection work to repair work.

  7A and 7B, a tool (for example, an underwater camera) 26 for performing each of these operations is fixed to the replacement head base 25, and only this portion can be separated from the main body. Means are shown. That is, the tool 26 is suspended by the wire 16 and fixed to the replacement head base 25. The replacement head base 25 is provided with an engaging stator 24 having, for example, a triangle whose lower end side is narrower and having a flange portion formed at the lower end.

  FIGS. 7C and 7D show the configuration of the main body base 21 for holding the stator 24. That is, the main body base 21 is provided with a fixed cylinder 23, and the fixed cylinder 23 is provided with a fixed block 22 that can be opened and closed left and right. A stator 24 for holding a tool (for example, an underwater camera) 26 shown in FIGS. 7A and 7B is inserted into the fixed block 22 from above, and the fixed block 22 is closed so that the stator 24 is closed. The lower end of the is detachably clamped.

  In this way, the stator 24 of the replacement head base 25 enters the fixing block 22 of the main body base 21, and then the fixing cylinder 23 is operated to close the fixing block 22, thereby completing the tool mounting.

  As described above, various tools can be applied. For example, an underwater TV camera 26 is used for appearance inspection, an overflow flaw detection sensor is used for surface flaw detection, and an ultrasonic wave is used for inspection and defect sizing to the inside of the material. When carrying out repair work for the probe or the like, tools such as a grinder or an EDM electrode can be attached as necessary. When performing a single operation, the necessary tools may be set in advance in the work head 15, but when performing multiple operations with the same device, the device must be lifted each time the tool is replaced. Changing settings is cumbersome. Therefore, in the present embodiment, a means is employed in which the tool 26 for performing each operation is fixed to the replacement head base 25 and only this portion can be separated from the main body.

  Next, in order to move from the state installed on the internal pump guide rail 106 to the adjacent internal pump guide rail 106, it is once disconnected from the internal pump guide rail 106 and positioned again on the adjacent internal pump guide rail 106. Need to be clamped.

  FIGS. 8A to 8D are explanatory views showing an embodiment for simply carrying out this movement.

First, as shown in FIG. 8 (a), from the state where the apparatus is installed on a pair of internal pump guide rails 106a, the device support arm 14 is extended toward the adjacent internal pump guide rail 106b to be moved, As shown in FIG. 8B, the auxiliary clamp mechanism 20 is operated and held by the adjacent internal pump guide rail 106b.

  Subsequently, as shown in FIG. 8 (c), while holding the cable 16 so that the main body does not fall, the apparatus base lifting clamp mechanism 11 is released and the movement of the device support arm 14 is performed. It moves to the internal pump guide rail 106b side.

  In this state, as shown in FIG. 8D, the apparatus base lifting clamp mechanism 11 is actuated again, moored to the internal pump guide rail 106b, and the auxiliary clamp mechanism 20 is released, so that the adjacent internal pump The movement to the guide rail 106 is completed.

  In the above embodiment, the core shroud 103 is the access target. However, by changing the configuration around the equipment support arm 14, the surface of the reactor pressure vessel 101, the upper surface of the baffle plate, the internal pump 105, the diffuser It is also possible to access the impeller.

  As an example, FIG. 9 shows a state where the diffuser and the impeller of the internal pump 105 are accessed with the device support arm 14 as a head portion facing downward.

  Based on the above configuration, the annulus section access method according to the present embodiment will be described. First, the apparatus main body is hung near the internal pump guide rail 106 while supporting the cable 16. Thereafter, the attitude control fan 12 is operated, and the apparatus main body is pressed against the internal pump guide rail 106. Since the attitude control fans 12 are installed on the left and right, the apparatus main body can be directly opposed to the internal pump guide rail 106 by controlling the respective fan operation amounts, and then the apparatus is propelled with the same propulsive force. Thus, the internal pump guide rail 106 can be approached and pressed.

  In this state, the clamp wheels 33, 31, 32 are pressed against the internal pump guide rail 106 by operating the clamp cylinders 33, 34 attached to the apparatus base lifting clamp mechanism 11. Thereby, the apparatus base raising / lowering clamp mechanism 11 pinches | interposes the internal pump guide rail 106, and the whole apparatus is moored by the internal pump guide rail 106. FIG.

  When an abnormality occurs, the clamping force is lost by releasing the pressure of the clamp cylinders 33 and 34, and the apparatus can be recovered.

  In addition, as shown in FIG. 4, the internal pump guide rail 106 has a deformed L shape, so that the apparatus is displaced from front to back and from side to side by constraining the upper surface and the inclined surface of the internal pump guide rail 106. It is possible to moor so that there is no.

  The clamp wheel 30 has a drum shape and the upper surface and the inclined surface of the internal pump guide rail 106 can be constrained by one wheel, and the clamp wheels 31 and 32 are two sets of simple-shaped wheels and the internal pump. The upper surface of the guide rail 106 and the inclined surface can be restrained.

  When the clamp cylinders 33 and 34 are actuated, the clamp wheels 30 and 31 are drawn toward the internal pump guide rail 106 side. First, the wheels 30 hit the inclined surface of the internal pump guide rail 106 and are further drawn into the inclined surface. And the device is drawn toward the core shroud 103 until the wheel hits the upper surface of the internal pump guide rail 106.

  The clamp wheel 30 of the device base lifting clamp mechanism 11 is merely for fixing the device and guiding it against the internal pump guide rail 106. By applying a rotational driving force, the device can be lifted and lowered, and by detecting the amount of rotation of the other clamp wheels 31, 32, the amount of lift movement of the device can be detected and controlled.

  The apparatus is anchored to the internal pump guide rail 106, which is a structure, so that the absolute position of the core shroud 103 in the circumferential direction is determined. However, the absolute position is unclear at this point in the vertical direction. Since the funnel-shaped lead-in 116 is provided at the upper end of the internal pump guide rail 106, when the device is raised, the unit of the device base lifting clamp mechanism 11 finally comes into contact with the lead-in 116. It becomes.

  By installing the limit switch 35 in the contact portion, it can be detected that the apparatus has moved to the upper limit of the internal pump guide rail 106.

  By recognizing this position as a reference point, the absolute position of the core shroud 103 in the vertical direction can be determined.

  However, the absolute position of the core shroud 103 in the vertical direction may not be detected by the lead-in 116 at the upper end of the internal pump guide rail 106. For example, it may be a mutation point of an existing structure. Specifically, it can also be implemented by detecting the lower ring 115 by a proximity sensor attached to the surface of the core shroud 103 of the apparatus.

By the way, since the internal pump guide rail 106 shown in FIG. 1 is not installed in the entire vertical direction of the core shroud 103, there is a range that cannot be accessed even if the apparatus moves to the upper end of the internal pump guide rail 106. Become. Therefore, in the present invention, the apparatus is provided with the apparatus support arm elevating mechanism 13 and the apparatus support arm 14 is moved up and down to the surface of the core shroud 103 above the internal pump guide rail 106 by extending the columnar elevating tool 6 upward. It has a possible structure.

In order to access the work head 15 to the entire area of the core shroud 103, for example, as shown in FIG. 6, the equipment support arm 14 is longer than the intermediate points O1 and O2 of the adjacent internal pump guide rails 106a and 106b. If the working head 15 can access this part, the overlap of the access range can be ensured when the apparatus moves to the adjacent internal pump guide rails 106a and 106b.

In the present embodiment, the entire structure can be made smaller by adopting a structure that can be slid to the left and right at the fitting portion with the device support arm lifting mechanism 13 or by being telescopic with a telescopic mechanism.

  Furthermore, taking advantage of the feature that the annulus 104 of the improved boiling water reactor is wide, the equipment support arm 14 can be a multi-axis control robot arm. Therefore, it is possible to carry out complicated work from inspection work to repair work.

  As described above, in the present embodiment, the position accuracy is obtained by attaching to the internal pump guide rail 106 installed in the core shroud 103 of the improved boiling water reactor and scanning the inspection head using this as a guide. And more accurate inspection is possible.

  Further, the clamp portion has a stator structure that is a sliding mechanism or a rotating structure having a shape that can be positioned following the shape feature of the internal pump guide rail 106.

  In addition, the clamp unit sandwiches one of the internal pump guide rails 106 from both sides, or restrains the pair of internal pump guide rails 106 or the adjacent internal pump guide rails 106 as a whole, thereby mooring the apparatus. Is possible.

  The clamp portion has a mechanism in which two or more sets of stators are positioned on one of the internal pump guide rails 106 and one or more stators are positioned on the other, and at least one of the stator sets is moved in the left-right direction. By operating this mechanism, the internal pump guide rail 106 is sandwiched and the apparatus is stably anchored to the internal pump guide rail 106.

  Further, a limit switch 35 is installed at the upper part of the clamp part. When this limit switch 35 raises the apparatus, it comes into contact with the lead-in part 116 at the upper part of the internal pump guide rail 106 to thereby prevent the core shroud 103 from being contacted. The absolute position in the vertical direction can be detected.

  Further, a proximity switch or a limit switch is installed at a position with respect to the surface of the core shroud 103, and this detects a shape change in the lower ring portion, whereby an absolute position in the vertical direction with respect to the core shroud 103 can be detected.

  In addition, the device support arm 14 moves the head portion by the circumferential movement distance from the state where the annulus access device is installed on the internal pump guide rail 106 to the state where it is installed on the next internal pump guide rail 106. By having a movable structure, it is possible to access the entire surface of the core shroud 103 by scanning the head portion while moving the access device between the internal pump guide rails 106.

  In addition, since the connecting portion between the head portion and the device support arm 14 has a detachable structure, a multi-purpose work can be performed by simply exchanging a tool incorporated in the head.

  Further, by changing the configuration of the equipment support arm 14 and the head part, not only the core shroud 103 but also the wall and the mounting structure of the reactor pressure vessel 101 facing the core shroud 103, the upper surface of the baffle plate, the internal pump diffuser and the impeller are accessed. It is possible.

  Further, since the annulus 104 in the improved boiling water reactor has almost no structural obstacles and a wide clearance, the device support arm 14 can be a multi-axis control robot arm, which enables complicated work. It can be performed consistently from results inspection to repair work.

  In addition, an auxiliary clamp mechanism is provided at the tip of the device support arm 14, the adjacent internal pump guide rail 106 is captured by this auxiliary clamp mechanism, the body clamp is released, and the device support arm 14 is driven to thereby It is possible to move to the internal pump guide rail 106.

  In addition, the clamp part is driven by atmospheric pressure or hydraulic cylinder, or has an electromagnetic clutch, so that the internal pump guide rail 106 is not damaged by releasing the cylinder pressure or releasing the clutch in an emergency. It is possible to remove the main body of the apparatus.

  As described above, according to the present embodiment, it is possible to position various maintenance inspection devices 1 on the entire surface of the core shroud 103 and the annulus portion 104 with high accuracy based on the internal pump guide rail 106. Safety evaluation and repair work for the annulus section 104 of the boiling water reactor can be easily performed.

The longitudinal cross-sectional view which shows the apparatus suspension state to the annulus part by one Embodiment of this invention. FIG. 2 is a cross-sectional view of FIG. 1. The whole perspective view which shows the annulus part access apparatus by the said embodiment. The enlarged plan view which shows a part of annulus part access apparatus by the said embodiment as a cross section. The side view of FIG. Explanatory drawing which shows the range which a head part can access in the installation state by the said embodiment. (A)-(d) is explanatory drawing which shows the effect | action which replaces | exchanges a tool simply by the said embodiment. (A)-(d) is explanatory drawing which shows the apparatus movement method using the auxiliary clamp mechanism installed in the apparatus support arm end by the said embodiment. The longitudinal cross-sectional view which shows the apparatus suspension state to the annulus part by other embodiment of this invention.

Explanation of symbols

1 ‥ maintenance equipment, 2 ‥ device base, 3 ‥ device based attitude control mechanism, 6 ‥ columnar lifting device, 11 ‥ device based lifting clamp mechanism, 12 ‥ attitude control screw, 13 ‥ equipment supporting arm lifting mechanism, 14 Equipment support arm, 15 Working head, 16 Wire, 20 Auxiliary clamp mechanism, 21 Body base, 22 Fixed block, 23 Fixed cylinder, 24 Stator, 25 Replacement head base, 26 Tool 28a, arm, 29a, shaft, 30, 31, 32, clamp wheel, 33, clamp cylinder, 35, limit switch, 101, reactor pressure vessel, 102, reactor wall, 103, core shroud, 104, annulus, 105 ... Internal pump, 106 ... Internal pump guide rail, 110 ... Equipment access device, 112a ... Upper trunk, 12b ‥ lower torso, 114 ‥ upper ring, 115 ‥ lower ring, 116 ‥ lead-in portion, 117 ‥ core support plate, 119 ‥ weld line.

Claims (5)

An equipment access device to the annulus part that introduces maintenance inspection equipment into the annulus part of the improved boiling water reactor,
An equipment base that can be suspended in the furnace;
An apparatus base attitude control mechanism for controlling the attitude of the apparatus base;
A device base lifting clamp mechanism that anchors the device base to an internal pump guide rail that is fixedly installed vertically above the internal pump and at the outer peripheral position of the core shroud so that the height of the device base can be adjusted;
A device support arm that supports the maintenance inspection device and the auxiliary clamp device ;
A device support arm lifting mechanism for supporting the device support arm on the device base so that the height thereof can be adjusted ;
The equipment support arm is configured to be longer than the intermediate point between the adjacent internal pump guide rails,
The apparatus for accessing an annulus section, wherein the auxiliary clamp mechanism extends and holds the apparatus support arm toward the adjacent internal pump guide rail when moving in the circumferential direction . The device base elevating clamping mechanism, claims and a clamping wheels respectively engaging against the center side and one end side of the internal pump guide rail adjacent a pair that are opposed to each other inclined surface The apparatus access apparatus to the annulus part of Claim 1 . The equipment access device for an annulus part according to claim 2, wherein the maintenance / inspection equipment is detachably supported by the equipment support arm in the furnace by remote operation from outside the furnace. The apparatus access apparatus to the annulus part of Claim 2 provided with the position detector which detects the position of the existing structure in the said annulus part by the contact or proximity | contact to the said existing structure. 3. The annulus according to claim 2, wherein the equipment support arm is movable in a circumferential direction of the core shroud with respect to the plurality of internal pump guide rails arranged at intervals on an outer periphery of the core shroud. Equipment access device to the department.

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