JP4630949B2 - Vibration / deterioration monitoring apparatus and method - Google Patents

Description

  The present invention relates to a vibration / deterioration monitoring apparatus, and more particularly, to monitor vibration / deterioration of a monitoring object disposed in a vessel, in particular, a reactor internal structure such as a jet pump disposed in a reactor pressure vessel. The present invention relates to a deterioration monitoring device.

  In a boiling water reactor, a wedge (wedge) is used for a riser bracket in order to reduce fluid vibration of a jet pump that is one of recirculation system equipment used for adjusting the reactor water flow rate. However, this wedge may be deteriorated due to wear caused by fluid vibration. In particular, in increasing the output of an existing nuclear power plant, it is considered to increase the core flow rate. In that case, it is expected that the jet pump flow rate will increase and the vibration of the jet pump will also increase. . Therefore, from the viewpoint of ensuring the safety of the nuclear reactor, a technology for monitoring the vibration of the jet pump and the deterioration of the wedge from the outside of the reactor pressure vessel during the operation of the nuclear reactor is required.

  As such vibration / deterioration monitoring means, there is known a vibration / deterioration monitoring device (see Patent Document 1) of the in-furnace structure using ultrasonic waves. In Patent Document 2, when a similar method is used and a plurality of reflected waves are measured depending on the shape of the monitoring target, the plurality of reflected waves are separated and vibration displacement is measured with high accuracy. A method of monitoring is shown.

Japanese Patent Laid-Open No. 11-125688 JP 2004-361131 A

  The jet pump is an in-reactor structure existing in the reactor pressure vessel, and optical measurement means cannot be used to evaluate vibration through the reactor pressure vessel and the reactor water. In addition, mechanical measuring means such as strain gauges need to draw measurement lines inside and outside the pressure boundary, which is possible but practically difficult due to its complexity. Therefore, it is considered appropriate to measure and monitor the vibration of the jet pump from the outside of the reactor pressure vessel by the measurement monitoring means using ultrasonic waves described in Patent Document 1.

  On the other hand, for the vibration of the jet pump, there should be a vibration mode other than the vibration mode that vibrates in the radial direction of the reactor pressure vessel (direction perpendicular to the longitudinal direction of the jet pump) as a low-order eigenmode. Has been confirmed. However, in both of the above-mentioned patent documents, only the vibration in the same direction as the radial direction of the reactor pressure vessel described above, which is the ultrasonic incident direction, can be measured (monitored). Further, the constituent members of the jet pump have a curved surface, and there is a possibility that the ultrasonic waves reflected on the surface of the jet pump cannot be properly captured.

  Furthermore, since the wedge of the jet pump may be deteriorated due to wear caused by fluid vibration, it is necessary to check this wear state. Usually, this wear state is checked during the shutdown of the reactor. Regular inspections can only be carried out if the reactor pressure vessel is open. Therefore, when it is found that the wear of the wedge is extremely advanced and must be replaced, the preparation period for the wedge replacement becomes an extension period of the periodic inspection period as it is.

An object of the present invention is to provide a vibration / deterioration monitoring apparatus and method capable of grasping a change in position based on wear deterioration due to vibration of a monitoring object in a time series and notifying the replacement timing of the monitoring object before periodic inspection. There is.

  The vibration / deterioration monitoring apparatus according to the present invention is a vibration / deterioration monitoring apparatus that uses ultrasonic waves to monitor a position change based on wear deterioration due to vibration of a monitoring object disposed in a container. A plurality of ultrasonic sensors that are installed outside the container along the longitudinal direction of an object to transmit and receive ultrasonic waves, and the ultrasonic sensors that are transmitted by the ultrasonic sensor and reflected by the monitoring object The signal processing unit that performs signal processing on the ultrasonic waves received at the position to measure the position of the monitored object, and accumulates the time-series change of the position of the monitored object, and the time-series change of the accumulated position And a position change data associated with the progress of wear of the monitored object, and a calculation unit that predicts when the monitored object reaches the allowable wear amount. .

  Further, the vibration / deterioration monitoring method according to the present invention is a vibration / deterioration monitoring method that uses ultrasonic waves to monitor a positional change based on wear deterioration due to vibration of a monitoring object disposed in a container, The ultrasonic sensor receives a plurality of ultrasonic waves from a plurality of ultrasonic sensors installed outside the container along the longitudinal direction of the monitoring object, and then reflects the received ultrasonic waves. Signal processing is performed to measure the position of the monitored object, and the time series change of the position of the monitored object is compared with the position change data associated with the progress of wear of the monitored object. The time when the allowable wear amount is reached is predicted.

  According to the vibration / deterioration monitoring apparatus and method according to the present invention, it is possible to grasp a change in position based on wear deterioration due to vibration of a monitored object in a time series, and notify the replacement timing of the monitored object before a periodic inspection.

1 is a longitudinal sectional view showing a boiling water reactor to which a first embodiment of a vibration / deterioration monitoring apparatus according to the present invention is applied. The jet pump of FIG. 1 is shown, (A) is a front view, (B) is a horizontal sectional view, and (C) is an enlarged vertical sectional view of a main part. The principal part expanded block diagram which shows the structure of a vibration and deterioration monitoring apparatus with the reactor pressure vessel and jet pump of FIG. The perspective view which shows the corner reflector as a reflector in 2nd Embodiment of the vibration and deterioration monitoring apparatus which concerns on this invention. Explanatory drawing for demonstrating the propagation path of the ultrasonic wave by the corner reflector of FIG. 3 shows a third embodiment of the vibration / deterioration monitoring apparatus according to the present invention, in which (A) is a front view showing a stationary jet pump provided with a reflector, and (B) is a jet in FIG. 6 (A). Explanatory drawing which shows schematically an example of the vibration mode of a pump with an ultrasonic sensor etc. 4 shows a fourth embodiment of the vibration / deterioration monitoring device according to the present invention, in which (A) is a front view showing a stationary jet pump in which a reflector is installed, and (B) is a diagram of FIG. 7 (A). Explanatory drawing which shows schematically an example of the vibration mode of a jet pump with an ultrasonic sensor etc. FIG. A fifth embodiment of the vibration / deterioration monitoring device according to the present invention is shown together with a jet pump, wherein (A) shows the case of a normal vibration mode of the jet pump, and (B) shows the vibration during abnormal vibration of the jet pump. Explanatory drawing which roughly shows the case of a mode, respectively. 6 shows a vibration / deterioration monitoring apparatus according to a sixth embodiment of the present invention, where (A) is a front view showing a jet pump provided with a reflector, and (B) is an enlarged view of the IX portion of FIG. 9 (A). FIG. 10C is a cross-sectional view showing the case of the wedge in the normal position, and FIG. 9C is a cross-sectional view showing the case of the wedge in the position moved by the occurrence of wear by enlarging the IX portion of FIG. The block diagram which shows 7th Embodiment of the vibration and deterioration monitoring apparatus which concerns on this invention. Sectional drawing which expands a part of vibration and deterioration monitoring apparatus of FIG. 10, and shows the propagation path of an ultrasonic wave. The graph which shows the time-sequential change of the height position of the wedge 13. FIG. The block diagram which shows 8th Embodiment of the vibration and deterioration monitoring apparatus which concerns on this invention. (A) is a graph showing the relationship between the vibration amplitude and the frequency of the wedge, (B) is a graph showing the time-series change of the vibration frequency at which the vibration amplitude of the wedge is maximum, and (C) is the maximum value of the vibration amplitude of the wedge. The graph which shows the time-sequential change of. A ninth embodiment of the vibration / deterioration monitoring apparatus according to the present invention will be described. (A) shows the value of the vibration frequency at which the vibration amplitude of the wedge becomes maximum at the next time interval before the present time. (B) is a graph for predicting the maximum value of the vibration amplitude of the wedge at the next time interval ahead of the current time.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[A] First embodiment (FIGS. 1 to 3)
FIG. 1 is a longitudinal sectional view showing a boiling water reactor to which a first embodiment of a vibration / deterioration monitoring apparatus according to the present invention is applied. FIG. 2 is a front view showing the jet pump of FIG. FIG. 3 is an enlarged configuration diagram of a main part showing the configuration of the vibration / deterioration monitoring apparatus together with the reactor pressure vessel and the jet pump of FIG.

  A vibration / deterioration monitoring apparatus 10 shown in FIG. 3 is applied to, for example, the boiling water reactor 11 shown in FIG. 1, and the inside of the reactor pressure vessel 12 is provided from the outside of the reactor pressure vessel 12 as a vessel. The vibration of the in-furnace structure as a monitoring object arranged in the above, particularly the jet pump 13 is monitored using ultrasonic waves.

  Here, as shown in FIG. 1, the boiling water reactor 11 houses a core 14 in a reactor pressure vessel 12, and a number of fuel assemblies (not shown) constituting the core 14 are shroud 15. And is supported by the core support plate 16 and the upper lattice plate 17. The upper part of the shroud 15 is closed by a shroud head 18, and a steam / water separator 20 is installed in the shroud head 18 via a stand pipe 19. A steam dryer 21 is disposed in the reactor pressure vessel 12 above the steam separator 20.

  The steam generated in the reactor core 14 is separated from the moisture by the steam separator 20, dried by the steam dryer 21, reaches the upper dome 22, and reaches the turbine system from the main steam nozzle 23 through the main steam system. . (Both not shown). The steam that has worked in the turbine system becomes condensate, and is supplied as coolant 32 into the reactor pressure vessel 12 through the water supply pipe 24. The coolant (reactor water) 32 is pressurized by the recirculation pump 26 of the reactor recirculation system 25, and a plurality of jet pumps 13 arranged in an annular portion between the reactor pressure vessel 12 and the shroud 15 are used. Guided to the lower plenum 27 below the core 14.

  The plurality of jet pumps 13 are evenly arranged along the circumferential direction of the core 14 on a pump deck 28 installed in an annular portion between the reactor pressure vessel 12 and the shroud 15. Further, as shown in FIG. 2A, each jet pump 13 guides the coolant 32 pressurized by the recirculation pump 26 to the riser pipe 29 and further to the nozzle portion 31 via the elbow pipe 30. The surrounding coolant 32 is taken in by the nozzle portion 31, and after these coolants 32 are mixed in the inlet mixer pipe 33, they are discharged from the jet pump diffuser 34 to below the core 14.

  As shown in FIG. 2C, the inlet mixer pipe 33 is fitted at the lowermost end with a gap 40 </ b> A to the jet pump diffuser 34, and this fitting portion is referred to as a slip joint 40. As shown in FIG. 2B, the inlet mixer pipe 33 is supported via a wedge 36 and a set screw 36A using a riser bracket 35 installed on the riser pipe 29. As a result, the central axes of the inlet mixer pipe 33 and the jet pump diffuser 34 are aligned with each other. Therefore, the inlet mixer pipe 33 is adjusted so as not to collide with the jet pump diffuser 34 even by vibration caused by the flow α of the coolant 32 flowing through the gap 40A of the slip joint 40.

  However, due to the vibration of the fluid flowing through the gap 40A of the slip joint 40, sliding wear occurs between the riser bracket 35 and the wedge 36, or between the riser bracket 35 and the set screw 36A. May occur. Once this gap is generated, fluctuations in the flow of the fluid flowing through the gap 40A of the slip joint 40 increase, so that the slide between the riser bracket 35 and the wedge 36 or between the riser bracket 35 and the set screw 36A. Wear further increases, and eventually the inlet mixer tube 33 may collide with the jet pump diffuser 34. Further, the fluctuation of the gap 40 </ b> A of the slip joint 40 also affects the performance of the jet pump 13. Therefore, the wedge 36 and the set screw 36 </ b> A, particularly the wedge 36, which have deteriorated due to the progress of wear must be replaced, and the gap 40 </ b> A of the slip joint 40 must always be properly maintained.

  As shown in FIG. 1, the reactor pressure vessel 12 is configured such that the upper opening and the lower opening of the pressure vessel body 37 are closed by a vessel lid 38 and a lower mirror portion 39, respectively. The pressure vessel main body 37 forms an annular portion between which the jet pump 13 is disposed and the shroud 15.

  Now, in the nuclear power plant equipped with the boiling water reactor 11 configured as described above, the flow of the coolant 32 in the reactor pressure vessel 12 of the boiling water reactor 11 even in a normal operation state. The action causes minute vibrations in the jet pump 13. In order to monitor such a vibration phenomenon from the outside of the reactor pressure vessel 12, a vibration / deterioration monitoring device 10 (FIG. 3) is provided.

  As shown in FIG. 3, the vibration / deterioration monitoring apparatus 10 includes ultrasonic sensors 41 and 42 installed on the outer surface of the reactor pressure vessel 12 and a monitoring target portion of the jet pump 13, for example, a riser pipe 29. The reflectors 43 and 44 installed on the surface and the signal processing unit 45 electrically connected to the ultrasonic sensors 41 and 42 are configured.

  Each of the ultrasonic sensors 41 and 42 transmits and receives an ultrasonic wave, and includes a transducer 46, a converging unit 47, and a coplant 48. The ultrasonic waves generated by the transducer 46 are focused as parallel waves by the focusing unit 47, and the parallel ultrasonic waves are transmitted through the coplant 48.

  Each of the ultrasonic sensors 41 and 42 is fixedly installed on the outer surface of the reactor pressure vessel 12 by a fixing jig 49. At this time, the ultrasonic sensor 41 is installed such that its axis O1 is in a direction (X direction in FIG. 3) perpendicular to the longitudinal direction (Y direction in FIG. 3) of the riser pipe 29 in the jet pump 13. The ultrasonic sensor 42 is installed such that its axis O2 is in a direction (M direction) away from the X direction by a predetermined angle θ from the X direction to the Y direction.

  The reflectors 43 and 44 are installed at positions corresponding to the ultrasonic sensors 41 and 42 on the surface of the riser pipe 29 of the jet pump 13. That is, the ultrasonic wave transmitted from each of the ultrasonic sensors 41 and 42 passes through the reactor pressure vessel 12 (pressure vessel body 37), propagates through the coolant (reactor water) 32, and the riser of the jet pump 13. Head to tube 29. Reflectors 43 and 44 are installed at positions where the ultrasonic waves from the ultrasonic sensors 41 and 42 reach the riser tube 29, respectively. Each of the reflectors 43 and 44 includes planar reflecting surfaces 43A and 44A capable of reflecting ultrasonic waves. The reflectors 43 and 44 are installed, for example, adjacent to each other in the vicinity of the longitudinal direction (Y direction) of the riser tube 29.

  The respective ultrasonic waves reflected by the reflecting surface 43A of the reflecting body 43 and the reflecting surface 44A of the reflecting body 44 travel along paths opposite to the directions transmitted from the ultrasonic sensors 41 and 42 to the reflecting bodies 43 and 44. Each of the ultrasonic sensors 41 and 42 passes through and is received by the ultrasonic sensors 41 and 42. The signal processing unit 45 performs signal processing on each ultrasonic wave received by each of the ultrasonic sensors 41 and 42, measures vibration amplitude as vibration displacement in the X direction and M direction in the riser tube 29, and further The vibration amplitude in the Y direction in the tube 29 is calculated and measured.

That is, the signal processing unit 45 measures the amplitude Vx of the vibration in the X direction of the riser tube 29 from the propagation time of the ultrasonic wave transmitted and received by the ultrasonic sensor 41 using the propagation speed of the ultrasonic wave. A vibration waveform in the X direction of the riser tube 29 is obtained from the propagation time of the ultrasonic wave that changes every moment. Similarly, the signal processing unit 45 measures the amplitude Vm of the vibration in the M direction of the riser tube 29 from the propagation time of the ultrasonic wave transmitted and received by the ultrasonic sensor 42 and obtains the vibration waveform in the M direction. . Next, the signal processing unit 45 calculates the amplitude Vy in the longitudinal direction (Y direction) of the riser tube 29 orthogonal to the X direction from the amplitudes Vx and Vm in the X direction and M direction of the riser tube 29 using the following equation. Further, the vibration waveform in the Y direction is obtained.
[Equation 1]
Vy = (Vm ² −Vx ² ) ^1/2

  As described above, even during normal operation of the nuclear power plant, minute vibrations are generated in the jet pump 13 due to the flow of the coolant 32. For this reason, the signal processing 45 predicts the amplitude level in at least one direction of the X direction, the M direction, and the Y direction of the minute vibration during the normal operation in the riser pipe 29 of the jet pump 13, and the amplitude obtained by actual measurement. When the level exceeds the predicted amplitude level, the abnormal vibration is detected. Here, the prediction of the amplitude level during normal operation includes a case where the amplitude is actually measured in advance and a case where the amplitude is calculated in advance by numerical analysis.

  Therefore, according to the present embodiment, the following effects (1) to (3) are obtained.

  (1) Respective ultrasonic waves transmitted from the ultrasonic sensors 41 and 42 are applied to the reflectors 43 and 44 provided on the surface of the riser pipe 29 of the jet pump 13 and provided with the planar reflecting surfaces 43A and 44A, respectively. Therefore, even when the surface of the riser tube 29 has a curved surface, each of the ultrasonic sensors 41 and 42 is reflected from the reflecting surface 43A of the reflector 43 and the reflecting surface 44A of the reflector 44, respectively. Ultrasonic waves can be reliably received. For this reason, even if it is the riser pipe | tube 29 of the jet pump 13 which has a curved surface, the vibration can be monitored accurately using an ultrasonic wave.

  (2) The ultrasonic sensor 41 is installed in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the riser pipe 29 in the jet pump 13 and ultrasonic waves are generated in the M direction away from the X direction by a predetermined angle θ. A sensor 42 is installed to measure the vibration amplitude of the riser tube 29 in the X direction and the M direction, and the vibration amplitude in the Y direction is calculated from these amplitudes. In this way, since the vibration of the riser tube 29 can be captured in two orthogonal directions (X direction and Y direction), superior vibration monitoring can be realized compared to vibration monitoring in only one direction (for example, the X direction).

  (3) When the vibration of the riser pipe 29 in the jet pump 13 is monitored, the vibration amplitude level of the riser pipe 29 during normal operation of the nuclear power plant is predicted, and the vibration amplitude of the riser pipe 29 exceeds the amplitude level. Since the abnormal vibration is detected, it is possible to quickly cope with the abnormal vibration of the riser tube 29.

[B] Second embodiment (FIGS. 4 and 5)
FIG. 4 is a perspective view showing a corner reflector as a reflector in the second embodiment of the vibration / deterioration monitoring apparatus according to the present invention. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be simplified or omitted.

  The vibration / deterioration monitoring device 50 according to the present embodiment is different from the vibration / deterioration monitoring device 10 according to the first embodiment in that reflectors 51 and 52 are configured using a corner reflector 53 as a reflector. Is a point. Here, like the reflector 43, the reflector 51 is installed on the surface of the riser pipe 29 of the jet pump 13 so as to reflect the ultrasonic waves from the ultrasonic sensor 41. Similarly to the reflector 44, the reflector 52 is installed on the surface of the riser tube 29 so as to reflect the ultrasonic waves from the ultrasonic sensor 42.

  Whereas the reflectors 43 and 44 of the embodiment have one plane as the reflection surfaces 43A and 44A, the corner reflector 53 of the present embodiment has two planes orthogonal to each other as shown in FIGS. Are provided as reflecting surfaces 54 and 55. Accordingly, the ultrasonic waves transmitted from the ultrasonic sensors 41 and 42 and passing through the reactor pressure vessel 12 and the like are reflected by, for example, the reflecting surface 54 at the corner reflector 53 of the reflectors 51 and 52 and further reflected by the reflecting surface 55. Reflected and reflected in the same direction along a path parallel to the incident ultrasonic wave. The different propagation paths of the ultrasonic waves are indicated by a solid line A and a broken line B in FIG.

  Therefore, according to the present embodiment, the following effects (4) and (5) are obtained in addition to the same effects as the effects (1) to (3) of the first embodiment.

  (4) Since the reflectors 51 and 52 adopting the corner reflector 53 are installed in the riser pipe 29 of the jet pump 13, the ultrasonic waves transmitted from the ultrasonic sensors 41 and 42 are transmitted to the reflection surface of the corner reflector 53. By 54 and 55, it can reflect in the same direction as the incident direction. Therefore, the ultrasonic sensors 41 and 42 can reliably receive the reflected ultrasonic waves and improve the S / N ratio, and can monitor the vibration of the riser pipe 29 in the jet pump 13 with high accuracy.

  (5) In the reflectors 51 and 52 employing the corner reflector 53, the ultrasonic wave transmitted from the ultrasonic sensor 41 or 42 is reflected in a parallel path, so the ultrasonic sensors 41 and 42 are assumed to be installed. Even when the ultrasonic pumps 41 and 42 cannot be installed, the ultrasonic sensors 41 and 42 can be installed at positions where they can be installed, and the vibration of the riser pipe 29 in the jet pump 13 can be monitored.

[C] Third embodiment (FIG. 6)
6A and 6B show a third embodiment of the vibration / deterioration monitoring device according to the present invention, in which FIG. 6A is a front view showing a stationary jet pump in which a reflector is installed, and FIG. FIG. 7 is an explanatory diagram schematically showing an example of a vibration mode of the jet pump of FIG. 6A together with an ultrasonic sensor and the like. The same parts of the vibration / deterioration monitoring device 60 of the third embodiment as those of the vibration / deterioration monitoring device 10 of the first embodiment are denoted by the same reference numerals, and the description is simplified or omitted. . In FIG. 6B, the inlet mixer pipe 33 indicates a stationary state by a broken line and a vibration state by a solid line.

  This embodiment is different from the first embodiment in that the monitoring target is an inlet mixer tube 33 having a curved surface on the surface of the jet pump 13, the ultrasonic sensor 42 is not installed, and the inlet mixer tube 33. The ultrasonic sensor 41 is installed only in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the above, the reflector 44 is not installed, and the reflector 43 that reflects the ultrasonic wave from the ultrasonic sensor 41 is In the normal vibration mode of the inlet mixer tube 33, the amplitude is relatively large and is installed at the surface portion of the inlet mixer tube 33.

  Here, the normal vibration mode of the inlet mixer pipe 33 means that the inlet mixer pipe 33 of the jet pump 13 in the nuclear reactor pressure vessel 12 is minute due to the flow of the coolant 32 during normal operation of the nuclear power plant. This is the vibration mode when it vibrates. This vibration mode may be actually measured in advance or may be calculated in advance by numerical analysis. Similarly to the first embodiment, the signal processing unit 45 detects that the measured amplitude of the inlet mixer tube 33 is abnormal when the amplitude level exceeds the amplitude level in the normal vibration mode.

  In FIG. 6, it is described that the reflector 43 is installed only on one of the two inlet mixer tubes 33 in the jet pump 13, but the reflector 43 is provided on each of the two inlet mixer tubes 33. The ultrasonic sensor 41 may be installed on the outer surface of the reactor pressure vessel 12 corresponding to these reflectors 43. Moreover, it may replace with the reflector 43 and the reflector 51 which employ | adopted the corner reflector 53 may be sufficient.

  Therefore, according to the present embodiment, in addition to the same effects as the effects (1), (3), (4) and (5) of the first and second embodiments, the following effects (6 ).

  (6) The reflector 43 or 51 is installed in a portion having a relatively large amplitude in the normal vibration mode of the inlet mixer tube 33. From this, the vibration detection sensitivity of the inlet mixer tube 33 can be increased, and the vibration monitoring of the inlet mixer tube 33 can be appropriately performed.

[D] Fourth embodiment (FIG. 7)
7A and 7B show a fourth embodiment of the vibration / deterioration monitoring apparatus according to the present invention, in which FIG. 7A is a front view showing a jet pump in a stationary state in which a reflector is installed, and FIG. It is explanatory drawing which shows schematically an example of the vibration mode of the jet pump of 7 (A) with an ultrasonic sensor etc. FIG. In the fourth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be simplified or omitted. In FIG. 7B, the inlet mixer tube 33 indicates a stationary state by a broken line and a vibration state by a solid line.

  The vibration / deterioration monitoring device 70 of the present embodiment is different from the vibration / deterioration monitoring device 10 of the first embodiment in that the monitoring object is an inlet mixer pipe 33 having a curved surface on the surface of the jet pump 13. Yes, the ultrasonic sensor 42 is not installed, and the ultrasonic sensor 41 extends in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the inlet mixer tube 33 along the longitudinal direction of the inlet mixer tube 33. A plurality of reflectors 43 are installed on the outer surface of the container 12, the reflector 44 is not installed, and the reflector 43 that reflects the ultrasound from the ultrasound sensor 41 corresponds to each of the ultrasound sensors 41. This is that a plurality of pipes 33 are installed along the longitudinal direction of the inlet mixer pipe 33.

  At least one of the plurality of reflectors 43 installed in the inlet mixer tube 33 is preferably installed at a position where the amplitude is relatively large in the normal vibration mode of the inlet mixer tube 33.

  Since the plurality of reflectors 43 are installed in the longitudinal direction (Y direction) of the inlet mixer tube 33 and the plurality of ultrasonic sensors 41 are installed corresponding to these reflectors 43, the signal processing unit 45 Instead of the vibration waveform at one point of the mixer tube 33, it is possible to determine the vibration waveforms at a plurality of points in the longitudinal direction in the inlet mixer tube 33, that is, the vibration mode of the entire inlet mixer tube 33. Furthermore, the signal processing unit 45 detects abnormal vibration when the vibration mode of the entire inlet mixer tube 33 obtained by measurement is different from the normal vibration mode of the inlet mixer tube 33.

  In FIG. 7, it is described that the reflector 43 is installed in only one of the two inlet mixer tubes 33 in the jet pump 13, but the reflector 43 is provided in each of the two inlet mixer tubes 33. Corresponding to these, the ultrasonic sensor 41 may be installed on the outer surface of the reactor pressure vessel 12. Moreover, it may replace with the reflector 43 and the reflector 51 which employ | adopted the corner reflector 50 may be sufficient.

  Therefore, according to the present embodiment, in addition to the effects (1), (4), and (5) of the first and second embodiments, the following effect (7) is achieved.

  (7) A plurality of ultrasonic sensors 41 and reflectors 43 or 51 are installed on the outer surface of the reactor vessel 12 and the surface of the inlet mixer tube 33 along the longitudinal direction of the inlet mixer tube 33, respectively. Can measure the vibration modes of the entire inlet mixer tube 33 and detect abnormal vibrations when these vibration modes are different from the normal vibration modes, so that it is possible to quickly cope with abnormal vibrations.

[E] Fifth embodiment (FIG. 8)
FIG. 8 shows a vibration / deterioration monitoring apparatus according to a fifth embodiment of the present invention together with a jet pump. FIG. 8A shows a case where the jet pump is in a normal vibration mode, and FIG. It is explanatory drawing which shows schematically the case of the vibration mode at the time of abnormal vibration of each. In the vibration / deterioration monitoring device 80 of the fifth embodiment, the same parts as those of the vibration / deterioration monitoring device 10 of the first embodiment are denoted by the same reference numerals, and the description is simplified or omitted. To do.

  The present embodiment is different from the first embodiment in that the monitored object is an inlet mixer tube 33 having a curved surface on the surface of the jet pump 13, the ultrasonic sensor 42 is not installed, and the inlet mixer tube The ultrasonic sensor 41 is installed in a direction (X direction) orthogonal to the longitudinal direction (Y direction) of 33, and the reflector 43 that reflects the ultrasonic waves from the ultrasonic sensor 41 is not installed. This is a point installed on the surface of the inlet mixer tube 33. Furthermore, the difference from the first embodiment is that the ultrasonic sensor 41 is in a position where the ultrasonic wave reflected from the reflector 43 can be received in the vibration mode when the inlet mixer tube 33 is in an abnormal vibration other than normal. It is the point where it was installed.

  That is, the ultrasonic sensor 41 is installed on the outer surface of the reactor pressure vessel 12, but at this time, the ultrasonic wave reflected from the reflector 43 cannot be received by the normal vibration of the inlet mixer tube 33 (FIG. 8). (A)) When the amplitude becomes large as in the case of abnormal vibration of the inlet mixer tube 33, the ultrasonic wave reflected from the reflector 43 is installed at a position where it can be received (FIG. 8B). Also in the present embodiment, instead of the reflector 43, the reflector 51 employing the corner reflector 53 may be used.

  Therefore, according to this embodiment, in addition to the effects (1), (4), and (5) of the first and second embodiments, the following effect (8) is achieved.

  (8) The ultrasonic sensor 41 cannot receive the ultrasonic wave reflected from the reflector 43 or 51 in the normal vibration mode of the inlet mixer tube 33, but reflects in the vibration mode when the inlet mixer tube 33 is abnormally vibrated. The ultrasonic wave reflected from the body 43 or 51 is installed at a position where it can be received. For this reason, it is possible to satisfactorily detect the occurrence of abnormal vibration in the inlet mixer tube 33, and it is possible to quickly implement the countermeasure.

[F] Sixth embodiment (FIG. 9)
9A and 9B show a sixth embodiment of the vibration / deterioration monitoring apparatus according to the present invention, in which FIG. 9A is a front view showing a jet pump provided with a reflector, and FIG. IX is a cross-sectional view showing the case of the wedge in the normal position, (C) is an enlarged view of the IX part in FIG. 9A, and shows the case of the wedge in the position moved by the occurrence of wear. It is sectional drawing shown. In the sixth embodiment, the same parts as those of the first embodiment are denoted by the same reference numerals, and the description will be simplified or omitted.

  The vibration / deterioration monitoring device 90 of the present embodiment is different from the vibration / deterioration monitoring device 10 of the first embodiment in that the monitored object is a wedge 36 having a curved surface on the surface of the jet pump 13. The ultrasonic sensor 42 is not installed, the ultrasonic sensor 41 is installed in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the wedge 36, and the reflector 43 reflects the ultrasonic waves from the ultrasonic sensor 41. Is the point installed on the wedge 36. Further, in the present embodiment, the ultrasonic sensor 41 is located at a position where the ultrasonic wave reflected from the reflector 43 installed on the wedge 36 cannot be received when the wedge 36 moves downward due to wear due to vibration. is set up.

  As described above, the wedge 36 is inserted between the riser bracket 35 and the inlet mixer pipe 33 in order to support the inlet mixer pipe 33 together with the riser bracket 35 installed in the riser pipe 29. The wedge 36 vibrates due to the flow of the coolant 32, deteriorates due to wear caused by the vibration, and moves downward, which may result in insufficient support of the inlet mixer tube 33.

  The ultrasonic sensor 41 receives the ultrasonic wave transmitted from the ultrasonic sensor 41 and reflected by the reflector 43 provided on the surface of the wedge 36, and the ultrasonic wave received by the ultrasonic sensor 41 is signal-processed. The unit 45 performs signal processing, measures the amplitude of the vibration of the wedge 36, and obtains the vibration waveform, whereby the vibration of the wedge 36 is monitored. At this time, the signal processing unit 45 can detect abnormal vibration of the wedge 36 when the measured amplitude of the wedge 36 exceeds the amplitude level of the wedge 36 during normal vibration.

  When wear due to vibration occurs in the wedge 36 and the wedge 36 moves downward, the ultrasonic wave from the ultrasonic sensor 41 is not reflected by the reflector 43, and the ultrasonic sensor 41 is not reflected by the reflector 43. In this case, the signal processing unit 45 can detect that the wedge 36 is worn and deteriorated. Instead of the reflector 43, a reflector 51 that employs a corner reflector 53 may be used.

  Therefore, according to the present embodiment, in addition to the effects (1), (3), (4) and (5) of the first and second embodiments, the following effect (9) is achieved.

  (9) The reflector 43 or 51 is installed on the wedge 36 of the jet pump 13, and the ultrasonic sensor 41 cannot receive the ultrasonic wave reflected from the wedge 36 due to movement due to wear based on the vibration of the wedge 36. It is installed in the position. For this reason, when the ultrasonic sensor 41 cannot receive an ultrasonic wave, the occurrence of wear of the wedge 36 can be detected, and the countermeasure against the wear deterioration of the wedge 36 can be quickly implemented.

[G] Seventh embodiment (FIGS. 10 to 12)
FIG. 10 is a block diagram showing a seventh embodiment of the vibration / deterioration monitoring apparatus according to the present invention. In the seventh embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be simplified or omitted.

  The vibration / deterioration monitoring apparatus 100 of the present embodiment differs from the vibration / deterioration monitoring apparatus 10 of the first embodiment in that the monitoring target is the wedge 36 of the jet pump 13 and the ultrasonic sensor 42 (FIG. 3) is not installed, and the ultrasonic sensor 41 is placed on the outer surface 12A of the reactor pressure vessel 12 along the longitudinal direction of the wedge 36 in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the wedge 36. A plurality of ultrasonic sensors are provided corresponding to the wedges 36 to form an ultrasonic sensor group 101, and a change in height position based on wear deterioration due to vibration of the wedges 36 is monitored in time series using ultrasonic waves.

  The reflector 44 (FIG. 3) is not installed. Further, the reflector 43 (FIG. 3) may be installed on the side surface of the wedge 36 and the outer wall surface 15 </ b> A of the shroud 15 corresponding to each ultrasonic sensor 41, but may not be installed. In the present embodiment, an example in which the reflector 43 is not installed is shown.

  The vibration / deterioration monitoring apparatus 100 according to the present embodiment includes a signal processing unit 102 and a calculation unit 103 in addition to the ultrasonic sensor group 101. The signal processing unit 102 and the calculation unit 103 may be configured integrally.

  As shown in FIG. 11, the signal processing unit 102 transmits ultrasonic waves transmitted from the ultrasonic sensors 41 of the ultrasonic sensor group 101, reflected by the wedge 36 or the shroud 15, and received by the ultrasonic sensors 41. The signal processing, that is, the comparison of the propagation time difference from the transmission to the reception of the ultrasonic wave, the height position of the upper end of the wedge 36 in the reactor pressure vessel 12 is measured. Reference numeral 104 in FIG. 11 indicates an ultrasonic propagation path.

  When wear due to vibration occurs in the wedge 36, the wedge 36 gradually descends by its own weight, and the height position changes. The calculation unit 103 accumulates the time series change E (FIG. 12) of the height position of the wedge 36. In this calculation unit 103, position change data F (FIG. 12) indicating how the wedge 36 changes its height position as wear progresses is separately calculated using vibration wear analysis or the like. Stored. The calculation unit 103 compares the time-series change E of the measured height position of the wedge 36 with the position change data F, and determines when the wedge 36 reaches the allowable limit height G corresponding to the allowable wear amount. Predict.

  Therefore, according to the present embodiment, the following effect (10) is obtained.

  (10) The ultrasonic sensor group 101 and the signal processing unit 102 measure the height position of the wedge 36, the calculation unit 103 accumulates time-series changes in the height position of the wedge 36, and the wedge 36 has an allowable limit height G. Since the time when the (allowable wear amount) is predicted is predicted, the degree of deterioration due to wear of the wedge 36 and the life of the wedge 36 can be grasped during the operation of the reactor by notifying the arrival time. For this reason, since the replacement time of the wedge 36 can be grasped before the periodic inspection of the reactor, the preparation for the replacement of the wedge 36 can be carried out during the operation of the reactor, and the preparation period for the replacement of the wedge 36 is increased. The situation that causes the extension of the periodic inspection period of the reactor can be avoided.

[H] Eighth embodiment (FIGS. 13 and 14)
FIG. 13 is a block diagram showing an eighth embodiment of the vibration / deterioration monitoring apparatus according to the present invention. In the eighth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be simplified or omitted.

  The vibration / deterioration monitoring apparatus 110 of the present embodiment is different from the vibration / deterioration monitoring apparatus 1 of the first embodiment in that the monitoring target is the wedge 36 of the jet pump 13 and the ultrasonic sensor 42 (FIG. 3) is not installed, and the ultrasonic sensor 41 is placed on the outer surface 12A of the reactor pressure vessel 12 along the longitudinal direction of the wedge 36 in the direction (X direction) orthogonal to the longitudinal direction (Y direction) of the wedge 36. A plurality of ultrasonic sensors 101 are installed corresponding to the wedges 36 to monitor the vibration of the wedges 36, the maximum value of the vibration amplitude of the wedges 36, the vibration frequency at which the vibration amplitude of the wedges 36 becomes the maximum, and the like. is there.

  The reflector 44 (FIG. 3) is not installed. Further, the reflector 43 (FIG. 3) may be installed on the side surface of the wedge 36 and the outer wall surface 15 </ b> A of the shroud 15 corresponding to each ultrasonic sensor 41, but may not be installed. In the present embodiment, an example in which the reflector 43 is not installed is shown.

  In addition to the ultrasonic sensor group 101, the vibration / deterioration monitoring apparatus 110 according to the present embodiment includes a signal processing unit 25, a calculation unit 111, a frequency analyzer 112, an alarm 113 as a warning unit, and a lighting lamp 114. Configured. The signal processing unit 25, the calculation unit 111, and the frequency analyzer 112 may be integrally configured.

  The signal processing unit 25 performs signal processing on the ultrasonic wave transmitted from each ultrasonic sensor 41 of the ultrasonic sensor group 101, reflected by the wedge 36 and received by the ultrasonic sensor 41, and outputs the X of the wedge 36. The vibration amplitude in the direction is measured, and a vibration waveform that is a time-series change of the vibration amplitude is obtained.

  The calculation unit 111 accumulates the time series change of the vibration amplitude of the wedge 36, and the frequency analyzer 112 performs frequency analysis of the time series change, and the vibration amplitude of the wedge 36 as shown in FIG. Finds the maximum vibration frequency and maximum vibration amplitude. The time-series change H (FIG. 14B) of the vibration frequency at which the vibration amplitude of the wedge 36 is maximum and the time-series change I (FIG. 14C) of the maximum value of the vibration amplitude of the wedge 36 are the frequency. Accumulated in the analyzer 112 or the calculation unit 111.

  In the calculation unit 111, a frequency change allowable value J that maximizes the vibration amplitude of the wedge 36 and an allowable value K of the maximum vibration amplitude value of the wedge 36 are calculated and stored in advance by vibration analysis. When the vibration frequency time-series change H at which the vibration amplitude of the wedge 36 becomes maximum reaches the allowable value J, or the time-series change I of the maximum vibration amplitude of the wedge 36 reaches the allowable value K. When this happens, a warning signal is output to the alarm 113 and the lighting lamp 114. The alarm 113 and the lighting lamp 114 receive the warning signal and issue an audible and visual warning, respectively.

  Therefore, according to the present embodiment, the following effect (11) is obtained.

  (11) The frequency analyzer 112 obtains the vibration frequency at which the vibration amplitude of the wedge 36 is maximum and the maximum value of the vibration amplitude from the time series change of the vibration amplitude of the wedge 36, and the calculation unit 111 performs vibration of the wedge 36. When the time-series change H of the vibration frequency with the maximum amplitude reaches the allowable value J or when the time-series change I of the maximum value of the vibration amplitude of the wedge 36 reaches the allowable value K, the alarm 113 and the lighting lamp 114 is activated, and the fact is announced. Therefore, the degree of deterioration due to vibration and wear of the wedge 36 and the life of the wedge 36 can be grasped during the operation of the reactor, and the replacement time of the wedge 36 can be recognized before the periodic inspection of the reactor. As a result, the preparation for the replacement of the wedge 36 can be performed during the operation of the nuclear reactor, so that a situation in which the preparation period for the replacement of the wedge 36 causes an extension of the periodic inspection period of the reactor can be avoided.

[I] Ninth Embodiment (FIG. 15)
FIG. 15 is a diagram for explaining a ninth embodiment of the vibration / deterioration monitoring apparatus according to the present invention. It is a graph for predicting a frequency value, and (B) is a graph for predicting the maximum value of the vibration amplitude of the wedge at the next time interval ahead of the current time. In the ninth embodiment, the same parts as those in the first and eighth embodiments are denoted by the same reference numerals, and the description will be simplified or omitted.

  The vibration / deterioration monitoring apparatus 120 (FIG. 13) of the present embodiment is different from the vibration / deterioration monitoring apparatus 110 of the eighth embodiment in that the vibration frequency value at which the vibration amplitude of the wedge 36 is maximized is set. Predicting or predicting the maximum value of the vibration amplitude of the wedge 36 and issuing an alarm when these predicted values reach an allowable value J or K.

  That is, the calculation unit 111 according to the present embodiment samples the time-series change of the vibration frequency accumulated in itself or in the frequency analyzer 112, at which the vibration amplitude of the wedge 36 is maximized, at regular time intervals. Plot as shown by the black dots at 15 (A). In addition, the calculation unit 111 obtains an (N−1) -order algebraic outer insertion function from N time-series data having the same vibration frequency of the wedge 36 sampled in the past, and uses this outer insertion function to predict the frequency. The curve L is obtained and stored.

  The calculation unit 111 compares the time series change of the above-described vibration frequency sampled at a certain time interval with the frequency prediction curve L, and calculates the vibration frequency having the maximum vibration amplitude at the next time interval ahead of the current time. A value is predicted as a predicted value N. The calculation unit 111 outputs a warning signal to the alarm 113 and the lighting lamp 114 when the predicted value N reaches a frequency change allowable value J calculated in advance by numerical analysis. A visual warning is output by the lighting lamp 114, respectively.

  Alternatively, the calculation unit 111 according to the present embodiment samples the time series change of the maximum value of the vibration amplitude of the wedge 36 accumulated in itself or in the frequency analyzer 112 at a constant time interval, so that FIG. Plot as shown in black dots. Further, the calculation unit 111 obtains an outer insertion function of the (N−1) -th order algebra from N pieces of time series data having the same vibration amplitude maximum value of the wedge 36 sampled in the past, and uses this outer insertion function. An amplitude prediction curve O is obtained and stored.

  The calculation unit 111 compares the above-described time-series change of the maximum value of the vibration amplitude sampled at a certain time interval with the amplitude prediction curve O, and determines the maximum value of the vibration amplitude at the next time interval ahead of the present time. Is predicted as a predicted value P. Then, the calculation unit 111 outputs a warning signal to the alarm 113 and the lighting lamp 114 when the predicted value P reaches the allowable value K of the vibration amplitude maximum value calculated in advance by numerical analysis. Visual warnings are output by the lighting lamps 114, respectively.

  Therefore, according to the present embodiment, the following effect (12) is obtained.

  (12) When the predicted value N of the vibration frequency at which the vibration amplitude of the wedge 36 becomes maximum reaches the allowable value J of the frequency change in the next time interval before the current time, or the maximum value of the vibration amplitude of the wedge 36 When the predicted value P in the next time interval ahead of the current time reaches the allowable value K of the maximum value of the vibration amplitude, the alarm 113 is activated and the lighting lamp 114 is lit. In addition to the same effects as the embodiment, a sufficient preparation period for exchanging the wedge 36 can be secured.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, the same effects can be obtained even if the reflectors 43, 44, 51, and 52 are formed integrally with the monitoring target or have a reflecting surface formed on a part of the monitoring target. In the present embodiment, the case where the monitoring target is the jet pump 13 has been described, but other internal structures such as the shroud 15 and the steam separator 20 that vibrate in the reactor pressure vessel 12 are provided. Also good. Furthermore, the monitoring object may be a device installed in a vessel or tank other than the reactor pressure vessel 12, an inner tube of a double tube, or a tube in a heat exchanger.

10 Vibration / deterioration monitoring device 12 Reactor pressure vessel (vessel)
13 Jet pump (monitoring target)
29 Riser tube (monitoring object)
33 Inlet mixer tube (monitoring object)
36 Wedge (object to be monitored)
40, 41, 42 Ultrasonic sensor 43, 44 Reflector 43A, 44A Reflective surface 45 Signal processing unit 50 Vibration / deterioration monitoring device 51, 52 Reflector 53 Corner reflector 54, 55 Reflective surface 60, 70, 80, 90 Vibration / Deterioration monitoring device 100 Vibration / deterioration monitoring device 101 Ultrasonic sensor group 102 Signal processing unit 103 Calculation unit 110 Vibration / deterioration monitoring device 111 Calculation unit 112 Frequency analyzer 113 Alarm (warning means)
114 Lighting lamp (Warning means)
120 Vibration / deterioration monitoring device F Position change data G Allowable limit height (allowable wear)
H Time series change of vibration frequency I Time series change of maximum value of vibration amplitude J Allowable value of frequency change K Allowable value of maximum vibration amplitude L Frequency prediction curve N Expected value O Expected amplitude curve P Expected value Vx, Vy Amplitude

Claims (3)

A vibration / deterioration monitoring device that uses ultrasonic waves to monitor positional changes based on wear deterioration due to vibration of an object to be monitored disposed in a container,
A plurality of ultrasonic sensors that are installed outside the container along the longitudinal direction of the monitoring object, and that transmit and receive ultrasonic waves; and
A signal processing unit that performs signal processing on the ultrasonic wave transmitted by the ultrasonic sensor, reflected by the monitoring object, and received by the ultrasonic sensor, and measures the position of the monitoring object;
The time-series change of the position of the monitoring object is accumulated, and the time-series change of the accumulated position is compared with the position change data associated with the progress of wear of the monitoring object. A vibration / deterioration monitoring device comprising: a calculation unit that predicts a time when the wear amount is reached. The vibration / deterioration monitoring apparatus according to claim 1, wherein the vessel is a reactor pressure vessel, and the monitoring target is a wedge of a jet pump disposed in the reactor pressure vessel. A vibration / deterioration monitoring method that uses ultrasonic waves to monitor positional changes based on wear deterioration due to vibration of a monitoring object disposed in a container,
The ultrasonic sensor receives a plurality of ultrasonic waves from the ultrasonic sensors installed outside the container along the longitudinal direction of the monitoring object after being reflected by the monitoring object,
The received ultrasonic waves are signal processed to measure the position of the monitoring object,
The time series change of the position of the monitored object is compared with the position change data associated with the progress of wear of the monitored object, and the time when the monitored object reaches the allowable wear amount is predicted. Vibration / deterioration monitoring method.

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