JP2019027361A - Pump monitor device and pump monitor method - Google Patents

Abstract

To detect underwater vortexes occurring in a suction sump with high accuracy.SOLUTION: A pump monitoring device 30 includes: a sensor 32 which is disposed on a bottom wall 3 of a suction sump 1 and detects a liquid pressure at the lower side of a pump casing 12; and a controller 50 which determines whether or not an underwater vortex A occurs in the suction sump 1 based on change of the pressure detected by the sensor 32. The sensor 32 is disposed in a movable body 34 which can be moved on the bottom wall 3 by a liquid current in the suction sump 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pump monitoring apparatus and a pump monitoring method.

  In the drainage station, underwater vortices extending from the bottom wall of the suction water tank toward the suction port are generated as the liquid level in the suction water tank becomes lower due to the operation of the pump. Since the vortex core of this underwater vortex is cavitation, the discharged fluid in the pump casing is a two-phase flow of liquid and gas. The underwater vortex is one of the causes of the vibration of the pump and also causes the deterioration of the installation floor. Patent Document 1 discloses a pump facility in which an ultrasonic sensor including a transmitter and a receiver is arranged in a suction water tank so that an underwater vortex generated in the suction water tank can be detected.

JP 2017-31948 A

  The liquid that has flowed into the suction water tank contains foreign matter (solid matter). Therefore, in the pump equipment of patent document 1, since an ultrasonic sensor may detect a foreign material, the detection accuracy of an underwater vortex is low.

  An object of the present invention is to provide a pump monitoring apparatus and a pump monitoring method that can detect an underwater vortex generated in a suction water tank with high accuracy.

  When the liquid level in the suction water tank is higher than a predetermined position, the flow of the liquid is low speed, so that no underwater vortex is generated in the suction water tank. When the liquid level in the suction water tank decreases due to the discharge, the flow of the liquid becomes high speed, so that an underwater vortex is generated in the suction water tank. Then, since air continuously enters the pump casing, the exhausted fluid becomes a gas-liquid two-phase flow, and the total pump head is lower and the discharge amount is smaller than in the case of a single-phase flow with only liquid. Moreover, the center pressure of the underwater vortex decreases as the underwater vortex grows. The present invention has been made based on such new findings.

  The present invention is a pump monitoring device in which at least a part of a pump casing is disposed in a suction water tank, the sensor being disposed on a bottom wall of the suction water tank, and detecting a liquid pressure below the pump casing; And a controller for determining whether or not an underwater vortex is generated in the suction water tank according to a change in pressure detected by the sensor.

  According to this pump monitoring apparatus, since the liquid pressure below the pump casing is detected by the sensor, it is possible to determine whether or not an underwater vortex that changes the liquid pressure is generated. Moreover, since the liquid pressure in the suction water tank is not affected by the foreign matter mixed in the liquid, it is possible to detect the generation of the underwater vortex with high accuracy.

  The sensor is disposed on a movable body that is movable on the bottom wall by a liquid flow in the suction water tank. The liquid in the suction water tank flows below the pump casing in which the inflow port is formed. Therefore, according to this aspect, the movable body can be automatically arranged below the pump casing where the underwater vortex is likely to occur. Further, when an underwater vortex is generated, the movable body approaches the underwater vortex due to a liquid flow and a pressure change caused by the underwater vortex. Therefore, the change (decrease) in the liquid pressure due to the underwater vortex can be reliably detected by the sensor. Further, the movable body moves to the center of the submerged vortex where the pressure has dropped. Therefore, since the movable body covers the starting point of the underwater vortex on the bottom wall, it is possible to suppress the generation of the subsequent underwater vortex at that portion while the underwater vortex disappears by the movable body.

  A detection-side transmission unit that is arranged on the movable body and wirelessly transmits a detection result of the sensor, and is arranged on the suction water tank and outputs the detection result from the detection-side transmission unit that is wirelessly received to the controller. A monitoring-side receiving unit. According to this aspect, since there is no communication wiring between the controller and the sensor, the movement of the movable body due to the wiring can be prevented.

  Arranged in the upper part of the suction tank, a radio wave transmitter for wirelessly transmitting a reference signal for positioning, a detector-side receiver for wirelessly receiving the reference signal, and disposed in the movable body A positioning unit that measures the position of the movable body based on a reference signal received by the detection-side receiving unit, and the controller includes a positioning unit that receives the monitoring-side receiving unit from the detection-side transmitting unit. Based on the positioning result, the position of the movable body in the suction water tank is specified. Here, specifying the position of the movable body is the same as specifying the location where the underwater vortex is generated. That is, according to this aspect, the controller can determine whether or not the underwater vortex is generated based on the detection result of the sensor, and can determine the position where the underwater vortex is generated based on the positioning result of the positioning unit. Therefore, the administrator of the pump facility during maintenance can improve the drainage efficiency of the pump by providing a structure for suppressing the generation of the underwater vortex in the portion where the underwater vortex is generated in the suction water tank.

  The movable body includes a plurality of convex portions projecting along the bottom wall. Alternatively, the movable body includes a reduced-diameter channel whose diameter is gradually reduced from the bottom wall side toward the pump casing side. According to these aspects, since the swirling flow of the liquid below the pump casing can be efficiently suppressed, generation or growth of the underwater vortex can be effectively suppressed.

  In the present invention, the sensor disposed on the bottom wall of the suction water tank detects the liquid pressure below the pump casing, and the controller detects the submerged vortex in the suction water tank by the change in the pressure detected by the sensor. Provided is a pump monitoring method for determining whether or not an occurrence has occurred.

  In the present invention, since the liquid pressure below the pump casing is measured by the sensor, it is possible to detect the presence or absence of underwater vortices with high accuracy without being affected by foreign matter mixed in the suction water tank.

Sectional drawing of the pump installation using the pump monitoring apparatus of 1st Embodiment which concerns on this invention. The perspective view of the movable body arrange | positioned in a suction water tank. The block diagram of a structure of pump equipment. The graph which shows the relationship between the pressure with respect to the water level in a suction tank, and discharge amount. The plane sectional view of a suction tank. FIG. 2 is a partially enlarged cross-sectional view of the vertical shaft pump of FIG. 1. Sectional drawing of the pump installation using the pump monitoring apparatus of 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows pump equipment using a pump monitoring device 30 according to the first embodiment of the present invention. The pump facility includes a vertical shaft pump 10 that discharges a liquid such as rainwater flowing into the suction water tank 1 to the downstream side. The pump monitoring device 30 includes a pressure sensor 32 disposed in the suction water tank 1, and determines whether or not the underwater vortex A is generated based on the detection result of the pressure sensor 32.

(Outline of vertical shaft pump)
As shown in FIG. 1, the vertical shaft pump 10 includes a pump casing 12, a rotating shaft 22, and an impeller 25.

  The pump casing 12 is installed on the installation floor 2 that covers the upper side of the suction water tank 1. The pump casing 12 includes a pumping pipe 13 that passes through the mounting hole 2 a of the installation floor 2 and is disposed in the suction water tank 1, and a discharge pipe 19 that is disposed on the installation floor 2.

  The pumping pipe 13 includes a straight pipe 14, a vane case 15, and a bell mouth 17. The straight pipe 14 is a pipe having a uniform diameter, and extends downward from the mounting hole 2a. The vane case 15 is a generally elliptical cylindrical pipe bulging outward in the radial direction, and is connected to the lower end of the straight pipe 14. The bell mouth 17 is a pipe having a generally conical cylindrical shape that gradually increases in diameter toward the lower end, and is connected to the lower end of the vane case 15. The lower end of the bell mouth 17 is a suction port 18 for sucking the liquid in the suction water tank 1, and is arranged at a predetermined interval with respect to the bottom wall 3 of the suction water tank 1.

  The discharge pipe 19 includes a discharge elbow 20 connected to the upper end of the pumping pipe 13 and a water supply pipe (not shown) disposed on the installation floor 2. The discharge elbow 20 is a bent pipe whose axis is curved by 90 degrees, and is connected to the upper end of the straight pipe 14. The water pipe is a straight pipe having a straight axis. A flexible tube (not shown) that can be deformed in the axial direction and the radial direction is interposed between the discharge elbow 20 and the water supply pipe.

  The rotating shaft 22 penetrates the discharge elbow 20 and is disposed so as to be rotatable along the axis of the pumping pipe 13. The upper end of the rotating shaft 22 protrudes outward from the discharge elbow 20. The portion of the discharge elbow 20 through which the rotating shaft 22 passes is sealed in a liquid-tight manner by a shaft seal device 23.

  The impeller 25 is fixed to the lower end of the rotating shaft 22 located inside the vane case 15. A bearing casing 16 is disposed inside the vane case 15, and an impeller 25 is disposed below the bearing casing 16.

  A drive motor 27 is connected to the upper end of the rotating shaft 22. When the rotating shaft 22 is rotated by driving the drive motor 27, the impeller 25 rotates integrally with the rotating shaft 22, so that the liquid in the suction tank 1 is discharged downstream through the pump casing 12. .

  For example, when the liquid level in the suction water tank 1 is higher than that of the vane case 15, the flow of the liquid in the suction water tank 1 is low speed, so that the underwater vortex A and / or the air suction vortex B as shown in FIG. . When the liquid level in the suction water tank 1 is lower than that of the vane case 15 due to the discharge, the liquid flow in the suction water tank 1 becomes high speed, so that an underwater vortex A and / or an air suction vortex B are generated.

  The underwater vortex A is a liquid flow extending from the bottom wall 3 of the suction water tank 1 toward the suction port 18, and the air suction vortex B is a liquid flow generated from the liquid surface to the suction port 18. In a steady state in which these vortices A and B are not generated, air does not flow into the pump casing 12, so that the discharged fluid is a single-phase flow containing only liquid. Since the vortex core of the underwater vortex A is cavitation, when the underwater vortex A is generated, air flows into the pump casing 12 and the discharged fluid becomes a two-phase flow of liquid and gas. In the state where the air suction vortex B is generated, air is intermittently or continuously sucked into the vortex, so that the discharged fluid becomes a two-phase flow. When the discharge fluid is a two-phase flow, the total lift of the vertical pump 10 is lower and the discharge amount is smaller than when the discharge fluid is a single-phase flow. Moreover, since the vibration of the vertical shaft pump 10 is increased, the installation floor 2 is also deteriorated.

  Therefore, a pump monitoring device 30 is provided in the pump facility in order to detect the generation of the underwater vortex A that is difficult to visually confirm. A vortex suppression mechanism 60 is provided to eliminate the generated air suction vortex B and suppress subsequent generation.

(Outline of pump monitoring device)
As shown in FIGS. 1 to 3, the pump monitoring device 30 includes a pressure sensor 32 for detecting the liquid pressure below the pump casing 12, and whether or not the underwater vortex A is generated based on the detection result of the pressure sensor 32. And a controller 50 for determining the above.

  The pressure sensor 32 outputs a voltage (detection result) corresponding to the surrounding liquid pressure. The pressure sensor 32 is disposed on the bottom wall 3 by being housed in a movable body 34 that is movable on the bottom wall 3.

  The movable body 34 includes a housing in which a plurality of (four in this embodiment) rollers 35 are disposed on the bottom surface. The roller 35 includes a rotation shaft extending in a direction orthogonal to the bottom wall 3, and can rotate 360 degrees around the rotation shaft. The movable body 34 is formed of a material close to the density of the liquid (for example, vinyl chloride resin or rubber) so that the movable body 34 can move on the bottom wall 3 by the flow of the liquid without floating on the liquid in the suction water tank 1. Yes. The movable body 34 includes a plurality of convex portions 36 that protrude along the bottom wall 3. When the movable body 34 is viewed from above (opposite side of the roller 35), four convex portions 36 are projected at an interval of 90 degrees. When the movable body 34 is positioned below the pump casing 12, the convex portion 36 has a function of suppressing the swirling flow of the liquid and suppressing the generation or growth of the underwater vortex A.

  The movable body 34 is provided with an arrangement portion 37A for arranging the pressure sensor 32 and an arrangement portion 37B for arranging a detection side communication unit 40 described later. These arrangement portions 37A and 37B are formed of concave portions that are recessed downward from the upper surface. The upper portion of the placement portion 37 </ b> A is blocked by the pressure sensor 32. The upper portion of the placement portion 37B is sealed with a resin that can transmit radio waves (signals). In addition, the movable body 34 includes a storage unit for storing a control unit 42, a positioning unit 44, and a storage unit 46, which will be described later. The weight of the movable body 34 including the pressure sensor 32, the detection side communication unit 40, the control unit 42, the positioning unit 44, and the storage unit 46 is set to a weight that can move on the bottom wall 3 by the flow of liquid. Has been.

  The controller 50 is configured by a personal computer, for example, and is disposed on the installation floor 2. The controller 50 determines whether or not the underwater vortex A is generated in the suction water tank 1 based on the change in the detection result (liquid pressure) of the input pressure sensor 32. The controller 50 includes a storage unit 52 that stores the detection result of the pressure sensor 32, and the storage unit 52 stores a threshold T for determining whether or not the underwater vortex A is generated.

  The pressure sensor 32 and the controller 50 transmit and receive information such as detection results by wireless communication. In addition to the pressure sensor 32, a detection side communication unit 40 and a control unit 42 are disposed in the movable body 34. A monitoring communication unit 54 is disposed on the lower surface of the installation floor 2 that is the upper part of the suction water tank 1. However, the monitoring communication unit 54 may be disposed on the installation floor 2.

  The detection-side communication unit 40 and the monitoring-side communication unit 54 include transmission units 40a and 54a that transmit radio signals, and reception units 40b and 54b that receive radio signals. The detection side communication unit 40 is electrically connected to the control unit 42 via a communication cable, and the monitoring side communication unit 54 is electrically connected to the controller 50 via a communication cable. However, these may be wirelessly connected.

  The control unit 42 includes a microcomputer and other electronic devices. The control unit 42 is electrically connected to the pressure sensor 32 via an A / D converter (not shown), and drives the pressure sensor 32 every predetermined time (for example, 300 to 3600 seconds). When the detection result is input from the pressure sensor 32, the control unit 42 drives the detection side communication unit 40, and causes the detection side communication unit 40 (transmission unit 40a) to output the detection result to the controller 50.

  The monitoring side communication unit 54 (reception unit 54b) outputs the detection result from the detection side communication unit 40 wirelessly received to the controller 50. Accordingly, the controller 50 stores the detection result of the pressure sensor 32 in the storage unit 52. Further, the controller 50 determines whether or not the underwater vortex A is generated in the suction water tank 1 by comparing with the threshold value T stored in the storage unit 52.

  FIG. 4 shows the relationship between the liquid pressure below the pump casing 12 and the pump discharge amount with respect to the water level in the suction water tank 1. The horizontal axis of FIG. 4 is the water level in the suction water tank 1, and the vertical axis is the liquid pressure and the discharge flow rate ratio. As shown by a broken line in FIG. 4, the pump discharge flow rate ratio is constant until the underwater vortex A is generated regardless of the water level, but rapidly decreases when the underwater vortex A is generated. As shown by the solid line in FIG. 4, the pressure below the pump casing 12 decreases as the liquid level decreases, and when the underwater vortex A is generated, it rapidly decreases to below atmospheric pressure.

  As shown in FIG. 4, the detection result by the pressure sensor 32 becomes positive pressure when the underwater vortex A is not generated, and becomes negative pressure when the underwater vortex A is generated. Further, since the center pressure of the submerged vortex A decreases as the submerged vortex A grows, the detection result by the pressure sensor 32 also decreases as the submerged vortex A grows. That is, if the liquid pressure below the pump casing 12 is measured, it is possible to detect whether or not the underwater vortex A is generated and the strength of the underwater vortex A.

  Therefore, in this embodiment, the threshold value T is set to 0 Pa, and the controller 50 determines that the underwater vortex A is not generated if the detection result of the pressure sensor 32 exceeds the threshold value T, and the detection result of the pressure sensor is the threshold value. If it is lower than T, it is determined that it is determined that the underwater vortex A is generated. However, the threshold value T can be changed as necessary.

(Movement of movable body)
As shown in FIG. 5, the liquid that has flowed into the suction water tank 1 from the upstream side (left side in FIG. 5) of the pump equipment collides with the end wall 4 of the suction water tank 1, and turns toward the pump casing 12. . Moreover, by the operation of the vertical shaft pump 10, the liquid in the suction water tank 1 flows below the pump casing 12 in which the suction port 18 is formed.

  The movable body 34 arranged in the suction water tank 1 is automatically moved to the lower side of the pump casing 12 where the underwater vortex A is easily generated by the liquid flow in the suction water tank 1. At this time, since the pressure sensor 32 and the controller 50 transmit and receive the detection result by wireless communication, there is no communication wiring that hinders the movement of the movable body 34 between them. Therefore, the movable body 34 can be reliably moved within a range of 1.5 times the diameter of the suction port 18 below the pump casing 12, specifically, with respect to the axis of the pumping pipe 13.

  Therefore, the pressure below the pump casing 12 can be reliably detected by driving the pressure sensor 32 at predetermined time intervals. As a result, it is possible to detect whether or not the underwater vortex A that changes the liquid pressure below the pump casing 12 is generated. Further, since the liquid pressure in the suction water tank 1 is not affected by the foreign matter mixed in the liquid, it is possible to detect the presence or absence of the underwater vortex A with high accuracy.

  When the underwater vortex A is generated, the movable body 34 approaches the underwater vortex A due to the liquid flow and pressure change caused by the underwater vortex A. Therefore, the change (decrease) in the liquid pressure due to the underwater vortex A can be reliably detected by the pressure sensor 32. In addition, the movable body 34 moves to the center of the submerged vortex A where the pressure has decreased, and covers the starting point of the submerged vortex A on the bottom wall 3. The generation of the underwater vortex A can be suppressed. Therefore, since the vibration of the vertical shaft pump 10 and the deterioration of the installation floor 2 can be effectively suppressed, the reliability of the pump equipment can be improved.

(Identification of position of movable body)
The position of the movable body 34 moved by the liquid flow is where the underwater vortex A is generated. Therefore, specifying the position of the movable body 34 in the suction water tank 1 is the same as specifying the location where the underwater vortex A is generated. Therefore, as shown in FIGS. 1 and 3, in order to identify the moving position of the movable body 34, the pump monitoring device 30 has a radio wave transmission unit 56 disposed above the suction water tank 1. A positioning unit 44 is arranged.

  The radio wave transmitting unit 56 wirelessly transmits a reference signal for positioning into the suction water tank 1 every predetermined time (for example, 300 to 3600 seconds). The reference signal includes information on the attachment position of the radio wave transmission unit 56 and transmission time, for example, as in GPS (Global Positioning System) positioning. In this case, as shown in FIG. 1 and FIG. 5, four radio wave transmitters 56 are arranged on the lower surface of the installation floor 2 with an interval of 90 degrees around the pump casing 12. Note that the radio wave transmission unit 56 and the controller 50 of the present embodiment may be electrically connected or may not be connected.

  The positioning unit 44 is electrically connected to the control unit 42 and the storage unit 46 by a communication cable. The positioning unit 44 measures the position of the movable body 34 based on the reference signal of the radio wave transmission unit 56 received by the detection side communication unit 40 (reception unit 40b). Specifically, the positioning unit 44 calculates (measures) the distances to the individual radio wave transmission units 56 based on the received first to fourth reference signals, and the inside of the suction water tank 1 from all the calculation results (distances). Position your own position. This positioning result is output to the control unit 42, and the control unit 42 outputs the detection side communication unit 40 (transmission unit 40a) to the controller 50.

  The controller 50 identifies the position of the movable body 34 in the suction water tank 1 based on the positioning result of the positioning unit 44 received by the monitoring communication unit 54 (receiving unit 54b) and stores the position in the storage unit 52.

  The method of specifying the position of the movable body 34 in the suction tank 1 is not limited to the same method as GPS positioning, but IMES (Indoor Messaging System) positioning, Wi-Fi positioning, beacon positioning, PDR (Pedestrian Dead Reckoning) positioning. The method can be changed as necessary as long as the method includes a radio wave transmission unit 56 that wirelessly transmits a reference signal and a positioning unit 44 that measures a position based on the received reference signal.

  In the pump monitoring device 30 configured as described above, the controller 50 can determine whether or not the underwater vortex A is generated based on the detection result of the pressure sensor 32, and can specify the generation location of the underwater vortex A based on the positioning result of the positioning unit 44. Therefore, at the time of maintenance, the administrator knows a well-known structure that suppresses the generation of the underwater vortex A at a place where the movable body 34 on the bottom wall 3 stops for a long time, that is, a place where the underwater vortex A in the suction water tank 1 occurs. By providing, drainage efficiency of the vertical shaft pump 10 can be improved.

(Outline of vortex suppression mechanism)
As shown in FIGS. 1 and 5, the vortex suppressing mechanism 60 is disposed on the lower outer peripheral portion of the pumping pipe 13 and eliminates or suppresses the air suction vortex B generated in the suction water tank 1. This vortex suppression mechanism 60 includes a vortex suppression member 62 and an attachment frame 64 for movably mounting the vortex suppression member 62.

  The vortex suppressing member 62 is a circular member in a plan view extending in the vertical direction along the axis of the water pumping pipe 13 from the lower part of the bell mouth 17 to the upper part of the vane case 15. The vortex suppressing member 62 is formed in a hollow shape so that it can be moved by the liquid flow in the suction water tank 1. Four vortex suppression members 62 are arranged with a spacing in the circumferential direction with respect to the mounting frame 64. Referring to FIG. 5, the vortex suppressing member 62 is farthest from the outer peripheral portion of the pumped water pipe 13 than the first position from the first position (two on the left side in FIG. 5) close to the outer peripheral portion of the pumped water pipe 13. Through a second position (two on the right side in FIG. 5) and a third position opposite to the first position, a range of approximately 180 degrees is rotatably held.

  The mounting frame 64 is provided from the lower part of the bell mouth 17 to the upper part of the vane case 15, similarly to the vortex suppressing member 62. The mounting frame 64 includes a horizontal frame member 65, a vertical frame member 66, and a connecting member 67.

  The horizontal frame member 65 is an annular pipe coaxial with the axis of the pumping pipe 13, and is fixed to a fixing portion 17 a formed on the bell mouth 17 so as to be positioned on the upper outer peripheral portion of the suction port 18.

  The vertical frame member 66 is a straight pipe whose lower end is joined to the horizontal frame member 65 and extends along the axis of the pumped pipe 13 toward the upper part of the vane case 15. The vertical frame member 66 is made of a rigid body (metal) that is not deformed by the load caused by the inflow of liquid into the suction water tank 1 and the load from the vortex suppressing member 62. The vertical frame members 66 are provided in the same number (four in the present embodiment) as the vortex suppressing members 62 with a circumferential interval from the horizontal frame member 65. The vertical frame member 66 may fix a predetermined portion between the upper end and the middle to the vane case 15 and the bell mouth 17.

  The connecting member 67 is configured to connect the vortex suppressing member 62 to the vertical frame member 66 so as to be rotatable, that is, to connect the vortex suppressing member 62 to the pumping pipe 13 so as to be horizontally rotatable. It is provided in the place. As shown most clearly in FIG. 6, the connecting member 67 includes a cylindrical portion 68 that is rotatably attached to the vertical frame member 66, and an arm 69 that protrudes radially outward from the cylindrical portion 68.

  The vortex suppressing member 62 is provided with an insertion hole 63 penetrating in the radial direction. The arm 69 penetrates the insertion hole 63 and attaches the vortex suppressing member 62 movably along the arm 69. In order to prevent the vortex suppressing member 62 from dropping off, the arm 69 is provided with a retaining portion 70 having a diameter larger than the diameter of the insertion hole 63. The overall length of the arm 69 is set to a dimension that allows the vortex suppressing member 62 to be placed in a portion where the air suction vortex B is likely to be statistically generated.

  In the pump facility thus configured, the vortex suppressing member 62 rotates with respect to the pump casing 12 according to the liquid flow in the suction water tank 1. Then, when the water level in the suction water tank 1 is lowered by the operation of the vertical shaft pump 10 and the air suction vortex B is generated, the vortex suppressing member 62 moves onto the air suction vortex B by the liquid flow of the air suction vortex B. At this time, the vortex suppressing member 62 can move not only in the direction of rotation with respect to the vertical frame member 66 but also in the direction of contact with and away from the pump casing 12 along the arm 69, so To the air suction vortex B. Therefore, the generated air suction vortex B can be eliminated, and the subsequent generation of the air suction vortex B can be effectively suppressed.

  As described above, the pump equipment of this embodiment eliminates the submerged vortex A and the air suction vortex B by the liquid flow in the suction water tank 1 without using dedicated drive means or performing complicated control. Or can be suppressed. Therefore, since the vibration of the vertical shaft pump 10 and the deterioration of the installation floor 2 can be effectively suppressed, the reliability of the pump equipment can be improved.

(Second Embodiment)
FIG. 7 shows a pump facility using the pump monitoring device 30 of the second embodiment. The second embodiment is different from the first embodiment in that the movable body 75 has a conical cylinder shape.

  The movable body 75 includes a housing in which a reduced diameter channel 76 having a diameter that gradually decreases from the bottom wall 3 side toward the pump casing 12 side. A housing 77 for arranging the pressure sensor 32, the detection-side communication unit 40, the control unit 42, the positioning unit 44, and the storage unit 46 shown in FIG. 3 is formed below the movable body 75. As in the first embodiment, a roller 78 for moving on the bottom wall 3 is disposed at the lower portion of the accommodating portion 77. The pressure sensor 32 is arranged so as to detect the liquid pressure in the reduced diameter channel 76.

  Similar to the first embodiment, the movable body 75 automatically moves below the pump casing 12 where the underwater vortex A is likely to occur due to the liquid flow in the suction water tank 1. Further, when the underwater vortex A is generated, the movable body 75 approaches the underwater vortex A due to the liquid flow and pressure change caused by the underwater vortex A. Then, the movable body 75 moves to the center of the underwater vortex A where the pressure is reduced so that the underwater vortex A is positioned in the reduced diameter flow path 76.

  Therefore, by detecting the fluid pressure in the reduced diameter flow path 76 by the pressure sensor 32, the controller 50 can reliably determine whether or not the underwater vortex A is generated in the suction water tank 1 from the detection result. Moreover, since the swirling flow of the liquid below the pump casing 12 can be efficiently suppressed by the movable body 75, the generation or growth of the underwater vortex A can be effectively suppressed.

  The pump monitoring device 30 and the pump monitoring method of the present invention are not limited to the configuration of the above embodiment, and various modifications can be made.

  For example, the movable bodies 34 and 75 may be provided with an underwater camera capable of monitoring the inside of the suction water tank 1 (whether or not the underwater vortex A is generated). The movable bodies 34 and 75 may be configured such that vertical movement is restricted.

  The pressure sensor 32 may be disposed directly on the bottom wall 3 of the suction water tank 1. In this case, it is preferable to arrange a plurality of pressure sensors 32 within a range of 1.5 times the diameter of the suction port 18 with respect to the axis of the water pump 13. Further, it is preferable that the mounting hole 2a of the installation floor 2 is formed with a diameter corresponding to the diameter so that the pressure sensor 32 can be thrown in from the installation floor 2.

  Although the pressure sensor 32 and the controller 50 transmit and receive the detection result by wireless communication, the detection result may be transmitted and received by wired communication by connecting with a communication cable. The moving positions of the movable bodies 34 and 75 are not limited to the method using the positioning unit 44 and the radio wave transmission unit 56, and may be monitored by an underwater camera.

  The pump monitoring device 30 is not limited to the pump equipment using the vertical shaft pump 10 but can also be applied to pump equipment using a horizontal shaft pump in which the rotation shaft is horizontally arranged. Can be changed.

DESCRIPTION OF SYMBOLS 1 ... Suction water tank 2 ... Installation floor 2a ... Mounting hole 3 ... Bottom wall 4 ... End wall 10 ... Vertical shaft pump 12 ... Pump casing 13 ... Pumping pipe 14 ... Straight pipe 15 ... Vane case 16 ... Bearing casing 17 ... Bell mouth 17a ... Fixed part 18 ... Suction port 19 ... Discharge pipe 20 ... Discharge elbow 22 ... Rotating shaft 23 ... Shaft seal device 25 ... Impeller 27 ... Drive motor 30 ... Pump monitoring device 32 ... Pressure sensor 34 ... Movable body 35 ... Roller 36 ... Convex Unit 37A, 37B ... Arrangement unit 40 ... Detection side communication unit 40a ... Transmission unit 40b ... Reception unit 42 ... Control unit 44 ... Positioning unit 46 ... Storage unit 50 ... Controller 52 ... Storage unit 54 ... Monitoring side communication unit 54a ... Transmission unit 54b ... Receiving unit 56 ... Radio wave transmitting unit 60 ... Vortex suppression mechanism 62 ... Vortex suppression member 63 ... Insertion hole 64 ... Mounting frame 65 ... Horizontal frame member 66 ... Vertical frame member 67 ... Forming member 68 ... tubular portion 69 ... arm 70 ... retaining portion 75 ... movable member 76 ... reduced diameter channel 77 ... accommodating portion 78 ... roller A ... water vortex B ... air suction vortex

Claims (7)

A monitoring device for a pump in which at least a part of a pump casing is arranged in a suction water tank,
A sensor which is disposed on the bottom wall of the suction water tank and detects a liquid pressure below the pump casing;
A pump monitoring apparatus comprising: a controller that determines whether or not an underwater vortex is generated in the suction water tank based on a change in pressure detected by the sensor.   The pump monitoring device according to claim 1, wherein the sensor is arranged on a movable body that is movable on the bottom wall by a liquid flow in the suction water tank. A detection-side transmitter that is arranged on the movable body and wirelessly transmits a detection result of the sensor;
The pump monitoring apparatus according to claim 2, further comprising: a monitoring-side receiving unit that is disposed on an upper portion of the suction water tank and outputs the detection result from the detection-side transmitting unit that is wirelessly received to the controller. A radio wave transmitter that is disposed on the suction water tank and transmits a reference signal for positioning wirelessly;
A detection-side receiving unit that is arranged on the movable body and wirelessly receives the reference signal;
A positioning unit disposed on the movable body and measuring the position of the movable body based on a reference signal received by the detection-side receiving unit;
4. The pump monitoring according to claim 3, wherein the controller specifies a position of the movable body in the suction water tank based on a positioning result of the positioning unit received by the monitoring-side receiving unit from the detection-side transmitting unit. apparatus.   The pump monitoring device according to any one of claims 2 to 4, wherein the movable body includes a plurality of protrusions protruding along the bottom wall.   5. The pump monitoring device according to claim 2, wherein the movable body includes a reduced-diameter channel whose diameter gradually decreases from the bottom wall side toward the pump casing side. 6. The sensor located on the bottom wall of the suction tank detects the liquid pressure below the pump casing,
A pump monitoring method in which a controller determines whether or not an underwater vortex is generated in the suction water tank based on a change in pressure detected by the sensor.

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