JP7008460B2 - Pump monitoring device and pump monitoring method - Google Patents

Description

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

In order to reduce the cost required for inspecting a vertical shaft pump, a technique for detecting an abnormality in the pump casing without pulling up the pump casing is required. Patent Document 1 discloses a pump monitoring device in which a large number of accelerometers and pressure gauges are arranged in a pump casing so as to predict the occurrence of excessive vibration before the vibration of the pump casing becomes large.

Japanese Patent No. 3624289

The pump monitoring device of Patent Document 1 requires complicated calculations for predicting the timing of inspection or parts replacement, and also requires a large number of sensors such as an accelerometer and a pressure gauge.

An object of the present invention is to make it possible to determine the timing of pump inspection or parts replacement with a simple configuration without performing complicated calculations.

One aspect of the present invention connects a rotary shaft extending in the vertical direction, a bearing arranged on the lower end side of the rotary shaft , a prime mover having an output shaft, and a tip end of the output shaft and an upper end of the rotary shaft. A pump monitoring device including a speed reducer that transmits the rotation of the output shaft to the rotation shaft, and a first rotation sensor that is arranged on the rotation shaft and detects that the rotation shaft has rotated once. , The rotating shaft is arranged at the first position above the bearing in the rotating shaft, and the rotating shaft rotates once with the vibration of the rotating shaft corresponding to the distance between the rotating shaft and the rotating shaft at the first position. A first vibration detecting means for detecting a plurality of pieces in between, and a second position of the rotating shaft above the bearing and below the first vibration detecting means, and the rotating shaft at the second position. A second vibration detecting means that detects a plurality of vibrations of the rotating shaft corresponding to the distance between the two, and the output shaft is arranged on the outer periphery of the output shaft and the output shaft makes one rotation. Based on the detection results of the second rotation sensor, the first vibration detecting means, the second vibration detecting means, and the first rotation sensor, the first position and the second position are said to be the same. The locus of the shaft vibration of the rotating shaft is determined respectively, and the locus of the shaft vibration of the rotating shaft in the bearing is determined based on these judgment results, while the first rotation sensor and the second rotation are performed. Provided is a pump monitoring device provided with a determination means for determining an abnormality of the speed reducer based on the detection result of each of the sensors .

According to this pump monitoring device, it is possible to determine the locus of axial vibration of the rotating shaft at the first position and the second position where the vibration detecting means are arranged, based on the detection results of the two vibration detecting means and one rotation sensor. .. Then, the judgment means simply compares the two shaft vibration loci at different positions without performing complicated calculations, and the bearing of the rotating shaft is worn, the gap between the impellers is widened, and the unintended abnormality of the rotating shaft is found. Can be judged.

For example, when the bearing is worn, the vibration on the lower end side with respect to the axis of the rotating shaft becomes large, so that the diameter difference of the shaft vibration locus of the rotating shaft due to the detection results of the first vibration detecting means and the second vibration detecting means becomes large. Therefore, by monitoring the detection results of the first vibration detecting means and the second vibration detecting means, it is possible to easily determine the wear of the bearing, which is one of the causes of the vibration of the pump, that is, the timing of the inspection or replacement of parts of the pump. .. Further, by monitoring the shape of the shaft vibration locus of the rotating shaft, it is possible to determine an unintended abnormality such as an expansion of the gap of the impeller and a defect of the rotating shaft. Further, based on the detection result of the first rotation sensor arranged on the rotation shaft and the detection result of the second rotation sensor arranged on the output shaft, it is possible to determine the abnormality of the speed reducer connecting the rotation shaft and the output shaft. ..

The determination means is a determination result of the shaft vibration locus of the rotation shaft at the first position and the second position, a distance from the upper end of the rotation shaft to the first vibration detection means, and the first vibration detection means. Based on the distance from the second vibration detecting means to the second vibration detecting means and the distance from the second vibration detecting means to the bearing, the locus of the shaft vibration of the rotating shaft in the bearing is determined.

The rotary shaft is rotatably arranged in the pump casing so that the lower end side is located in the pump casing and the upper end side penetrates the pump casing and protrudes to the outside. The second vibration detecting means and the first rotation sensor are arranged in a portion of the rotation shaft protruding outward from the pump casing. Since the pump monitoring device of this aspect can be installed in the existing pump and can be installed only at the regular inspection period, the convenience of the pump administrator can be improved.

The first vibration detecting means and the second vibration detecting means are a non-contact type first vibration sensor and non-contacting first vibration sensors arranged at intervals of 90 degrees around the axis of the rotation axis with respect to the first vibration sensor. Each has a contact type second vibration sensor. According to this aspect, the shaft vibration of the rotating shaft can be reliably detected by the vibration detecting means.

Further, in the present invention, the first rotation sensor arranged on the rotation shaft extending in the vertical direction detects that the rotation shaft has rotated once, and is above and above the bearing arranged on the lower end side of the rotation shaft. The first vibration detecting means and the second vibration detecting means arranged at intervals above and below the rotating shaft cause the rotating shaft to generate vibration of the rotating shaft corresponding to the distance between the rotating shaft. A plurality of detections are made during one rotation, and based on the detection results of the first vibration detecting means, the second vibration detecting means, and the first rotation sensor, the determination means are the first vibration detecting means and the first vibration detecting means. 2 The locus of the shaft vibration of the rotating shaft at the first position and the second position where the vibration detecting means is arranged is determined, respectively, and the locus of the shaft vibration of the rotating shaft in the bearing is determined based on these determination results. On the other hand, the second rotation sensor arranged on the outer periphery of the output shaft of the prime mover detects that the output shaft has rotated once, and the determination means further determines the first rotation sensor and the second rotation sensor. Based on the detection results of each rotation sensor, a pump that connects the tip of the output shaft of the prime mover and the upper end of the rotation shaft to determine an abnormality in the speed reducer that transmits the rotation of the output shaft to the rotation shaft. Provide a monitoring method.

In the pump monitoring device of the present invention, the determination means can easily determine the timing of pump inspection or parts replacement based on the detection results of the two vibration detection means and one rotation sensor without performing complicated calculations.

The schematic diagram of the pump equipment which arranged the pump monitoring apparatus which concerns on embodiment of this invention. A block diagram showing the configuration of a pump monitoring device. The cross-sectional view which shows the structure of the vibration detection means. Sectional drawing which shows the structure of the rotation sensor. The graph which shows the output of two vibration detection means and one rotation sensor. Lissajous diagram of output signals of two vibration detection means.

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

FIG. 1 shows a pump monitoring device 40 (hereinafter abbreviated as “monitoring device”) according to an embodiment of the present invention arranged in a vertical shaft pump 10. By detecting the shaft vibration of the rotary shaft 21 of the vertical shaft pump 10, the monitoring device 40 determines the wear state of the bearing 23 of the rotary shaft 21, the widening of the gap of the impeller 27, and the unintended abnormality of the rotary shaft 21. It is something to do.

(Overview of vertical shaft pump)
As shown in FIG. 1, the building of the pump equipment in which the vertical shaft pump 10 is installed is provided with a bottom surface 1, a pump floor 2 provided above the bottom surface 1 at intervals, and a space above the pump floor 2. It is a two-bed type equipped with a motor floor 3. In this building, the water absorption tank 4 is formed between the bottom surface 1 and the pump floor 2, the pump chamber 5 is formed between the pump floor 2 and the motor floor 3, and the control chamber 6 is formed on the motor floor 3.

The vertical shaft pump 10 drains rainwater or the like that has flowed into the water absorption tank 4 to the downstream side, and includes a pump casing 12, a rotary shaft 21, and an impeller 27. Further, the vertical shaft pump 10 includes a prime mover 30 and a speed reducer 36 for rotating the rotary shaft 21.

The pump casing 12 is fixed to the pump floor 2 and includes a pumping pipe 13 arranged in the water absorption tank 4 and a discharge pipe 17 arranged in the pump chamber 5. The pumping pipe 13 includes a straight pipe 14, a vane casing 15, and a bell mouth 16, and is connected from the upper side to the lower side in this order. The discharge pipe 17 includes a discharge elbow 18 whose central axis is curved by 90 degrees, and is connected to the upper end of the straight pipe 14. A water pipe 19 for draining water to the downstream side is connected to the outlet of the discharge elbow 18.

The rotary shaft 21 is arranged so as to extend in the vertical direction from the inside of the water absorption tank 4 to the inside of the control chamber 6. The rotary shaft 21 of the present embodiment is composed of a spindle 22 arranged in the pump casing 12 and a drive shaft 24 that is separate from the spindle 22, but may be configured by one continuous shaft.

The main shaft 22 penetrates the discharge elbow 18 and is arranged along the central axis of the pumping pipe 13. The spindle 22 is rotatably supported by the pumping pipe 13 by an underwater bearing 23 which is a radial bearing. The upper end of the spindle 22 projects outward from the discharge elbow 18. The portion of the discharge elbow 18 through which the main shaft 22 penetrates is hermetically sealed by a shaft sealing device (not shown).

The drive shaft 24 is connected to the spindle 22 by a coupling 25. The upper end of the drive shaft 24 penetrates the motor floor 3 and projects into the control chamber 6.

The impeller 27 is fixed to the lower end of the spindle 22 located in the vane casing 15. A bearing case (not shown) is arranged inside the vane casing 15, a bearing 23 is arranged in the bearing case , and an impeller 27 is arranged under the bearing case.

A diesel engine, which is one of the internal combustion engines, is used as the prime mover 30. The prime mover 30 is arranged in the control chamber 6, is arranged parallel to the motor floor 3, and includes an output shaft 31 extending in a direction intersecting the rotation shaft 21. The output shaft 31 of the present embodiment is connected to the speed reducer 36 via a plurality of (three in this embodiment) intermediate shafts 32a to 32c. The output shaft 31 and the intermediate shaft 32a are connected via the coupling 33A, the intermediate shaft 32a and the intermediate shaft 32b are connected via the centrifugal clutch 34, and the intermediate shaft 32b and the intermediate shaft 32c are connected via the coupling 33B. ing.

The speed reducer 36 transmits the rotation of the output shaft 31 of the prime mover 30 to the rotating shaft 21, and is arranged in the control chamber 6. The lower end of the drive shaft 24 forming a part of the rotating shaft 21 and the tip of the intermediate shaft 32c forming a part of the output shaft 31 are connected to the speed reducer 36, respectively.

In this pump equipment, when the prime mover 30 is driven, the rotation of the output shaft 31 is decelerated by the speed reducer 36 and transmitted to the rotating shaft 21. By rotating the impeller 27 integrally with the rotating shaft 21, the water in the water absorption tank 4 passes through the inside of the pump casing 12 and is drained to the downstream side.

In the vertical shaft pump 10, when the bearing 23 is excessively worn, the pump casing 12 vibrates greatly, causing deterioration of the floors 2 and 3. In order to prevent this problem, a monitoring device 40 for early determination of the timing of inspection or replacement of parts of the vertical shaft pump 10 is provided.

(Overview of pump monitoring device)
As shown in FIGS. 1 and 2, the monitoring device 40 includes two vibration detectors 42A and 42B, two rotation sensors 46 and 47, and a controller 51. In this monitoring device 40, based on the detection results of the vibration detectors 42A and 42B and the rotation sensor 46, the determination unit 51a of the controller 51 determines the locus T3 of the shaft vibration of the rotation shaft 21 in the bearing 23 (see FIG. 6). ), That is, the configuration is such that the amount of wear of the bearing 23 is determined (predicted). The vibration detectors 42A and 42B and the rotation sensor 46 are arranged in the pump chamber 5, and the rotation sensor 47 and the controller 51 are arranged in the control chamber 6.

As shown in FIG. 1, the vibration detectors 42A and 42B are arranged at a portion protruding outward from the pump casing 12 of the rotary shaft 21 at intervals of upper and lower parts. The vibration detector 42A (first vibration detecting means) is arranged at a first position near the motor floor 3, and detects the vibration of the rotating shaft 21 at this first position. The vibration detector 42B (second vibration detection means) is arranged at a second position near the pump casing 12 so as to be located below the vibration detector 42A, and the vibration of the rotating shaft 21 at this second position. Is detected.

As shown in FIG. 3, the vibration detectors 42A and 42B are arranged in a ring-shaped mounting frame 43 surrounding the rotation shaft 21. The vibration detector 42A includes a non-contact type first vibration sensor 44A and a second vibration sensor 45A, and the vibration detector 42B includes a non-contact type first vibration sensor 44B and a second vibration sensor 45B.

The mounting frame 43 is fixed to the pump chamber 5 so that its inner diameter is larger than the outer diameter of the rotating shaft 21 and is located coaxially with the rotating shaft 21. This fixing is performed by a well-known structure using a frame including a bracket. As a result, inside the mounting frame 43, the rotating shaft 21 can rotate in a non-contact state.

The first vibration sensors 44A and 44B and the second vibration sensors 45A and 45B are fixed at intervals of 90 degrees around the axis of the rotating shaft 21 so as to be located in the gap between the mounting frame 43 and the rotating shaft 21. There is. As these vibration sensors 44A, 44B, 45A, 45B, eddy current type displacement sensors that measure the shaft vibration of the rotating shaft 21 can be used. This displacement sensor supplies a high-frequency signal to the coil to generate a magnetic flux, and outputs a voltage having a different value depending on the distance between the coil and the rotation shaft 21.

The rotation sensors 46 and 47 detect that the shafts 21 and 31 have rotated once around the axis of the rotating shafts 21 and 31, and are composed of an optical rotation angle sensor capable of detecting the rotation angle. There is. As shown in FIG. 1, the rotation sensor 46 is arranged on the outer periphery of the coupling 25 which constitutes a part of the rotation shaft 21. The rotation sensor 47 is arranged on the outer periphery of the coupling 33A which constitutes a part of the output shaft 31.

As shown in FIG. 4, the rotation sensors 46 and 47 are arranged in a ring-shaped mounting frame 48 surrounding the couplings 25 and 33A. The mounting frame 48 is fixed to the pump chamber 5 and the control chamber 6 so that the inner diameter thereof is larger than the outer diameter of the couplings 25 and 33A and is coaxial with the couplings 25 and 33A. This fixing is performed by a well-known structure using a frame including a bracket. As a result, inside the mounting frame 48, the couplings 25 and 33A can rotate in a non-contact state.

The couplings 25 and 33A are provided with slits 49 for detecting the rotation of the shafts 21 and 31. The slit 49 extends in the axial direction with respect to the couplings 25 and 33A, and is provided at only one position in the circumferential direction. When the slit 49 passes through the detection area of the rotation sensors 46, 47, the rotation sensors 46, 47 output a voltage having a value different from that when the other portion passes (see Z, Za in FIG. 5).

As shown in FIG. 2, the controller 51 is electrically connected to the prime mover 30, two vibration detectors 42A and 42B, two rotation sensors 46 and 47, and a monitor 52. The controller 51 processes the detection results input from the vibration detectors 42A and 42B and the rotation sensors 46 and 47, and is configured by a personal computer.

The controller 51 includes a determination unit (determination means) 51a including a CPU (central processing unit) and the like. As shown in FIG. 6, the determination unit 51a has the locus T1 and T2 of the shaft vibration of the rotation shaft 21 at the first position and the second position based on the detection results of the vibration detectors 42A and 42B and the rotation sensor 46. Is primarily determined, and based on the determination results T1 and T2, the locus T3 of the shaft vibration of the rotating shaft 21 in the bearing 23 is secondarily determined.

For example, in the newly installed vertical shaft pump 10, the diameter of the shaft vibration locus T1 of the vibration detector 42A and the diameter of the shaft vibration locus T2 of the vibration detector 42B are substantially the same. When the bearing 23 is worn, the space in which the rotary shaft 21 can move becomes wide, so that the runout on the lower end side of the rotary shaft 21 becomes large. Therefore, the diameter of the shaft vibration locus T2 of the vibration detector 42B located on the tip (free end) side of the rotation shaft 21 is the shaft vibration locus of the vibration detector 42A located on the base end (fixed end) side of the rotation shaft 21. It is larger than the diameter of T1. These diameter differences increase as the bearing 23 wears. This embodiment is based on such new findings.

Specifically, the detection results of the four vibration sensors 44A, 44B, 45A, 45B and the detection results of the rotation sensor 46 are input to the determination unit 51a at predetermined time intervals. This time is set to the length at which 24 or more detection results are input while the rotation shaft 21 makes one rotation. Let X1 and X2 be the detection results input from the first vibration sensors 44A and 44B, Y1 and Y2 be the detection results input from the second vibration sensors 45A and 45B, and Z be the detection results input from the rotation sensor 46. The time waveforms of the detection results X1, X2, Y1, Y2, Z are as shown in FIG. Note that FIG. 5 shows a case where the axial vibration of the rotating shaft 21 is larger in the second position where the vibration detector 42B is arranged than in the first position where the vibration detector 42A is arranged.

Referring to FIG. 5, the waveform X1 of the first vibration sensor 44A of the vibration detector 42A and the waveform Y1 of the second vibration sensor 45A are arranged at intervals in the circumferential direction of the rotating shaft 21, and the X of FIG. Phased in direction (time). The waveform X2 of the first vibration sensor 44B of the vibration detector 42B and the waveform Y2 of the second vibration sensor 45B are also in phase by the amount arranged at intervals in the circumferential direction of the rotating shaft 21. The waveforms X1 and Y1 of the vibration sensors 44A and 45A of the vibration detector 42A and the waveforms X2 and Y2 of the vibration sensors 44B and 45B of the vibration detector 42B are shown in FIG. 5 according to the difference in the vibration width of the rotation shaft 21. The amount of displacement in the Y-axis direction is different.

The waveforms X1 and Y1 of the vibration detector 42A and the waveforms X2 and Y2 of the vibration detector 42B are processed, and one rotation of the rotation shaft 46 is shown in a resage diagram based on the detection result (rising portion Za) of the rotation sensor 46. Then, it becomes as shown in FIG. Referring to FIG. 6, the axis vibration locus T2 based on the detection result of the vibration detector 42B has a larger diameter than the shaft vibration locus T1 of the vibration detector 42A.

Referring to FIG. 1, the vibration detector 42A is arranged at the first position of L1 at a distance from the upper end (base end) of the rotating shaft 21, and the vibration detector 42B has a distance of L2 from the vibration detector 42A. The bearing 23 is arranged at the second position, and the bearing 23 is arranged at the third position of L3 at a distance from the vibration detector 42B. Therefore, the locus T1 is fitted to the first position, the locus T2 is fitted to the second position, and the tangent line S of the loci T1 and T2 is calculated by the determination unit 51a. Then, the determination unit 51a calculates (determines) the diameter of the axis vibration locus T3 of the rotating shaft 21 in the bearing 23 based on the diameters of the loci T1 and T2 and the distances L1 to L3.

The predicted locus T3 in the bearing 23 is larger than the locus T2 by the vibration detector 42B at the second position. If the predicted locus T3 (the gap between the bearing 23 and the rotating shaft 21) becomes excessively large, vibration of the pump casing 12 that causes deterioration of the floors 2 and 3 occurs. Therefore, by setting a threshold value for the diameter of the locus T3 in advance and comparing (monitoring) the diameter of the predicted locus T3 with the threshold value, the determination unit 51a can easily perform wear of the bearing 23, that is, a time for inspection or replacement of parts. Can be judged. Further, by monitoring the shapes of the shaft vibration trajectories T1 and T2 of the rotating shaft 21, the determination unit 51a does not intend not only the wear of the bearing 23 but also the widening of the gap of the impeller and the loss of the rotating shaft 21. Abnormalities can also be judged.

The controller 51 causes the monitor 52 to display the next determination result based on the determination result of the determination unit 51a. Further, when the determination result of the diameter of the locus T3 by the determination unit 51a exceeds the threshold value, the controller 51 causes the monitor 52 to display a warning. This makes it possible for the operator to easily confirm the state of the vertical shaft pump 10.

Further, the determination unit 51a of the present embodiment can determine an abnormality of the speed reducer 36 by comparing the detection results of the rotation sensor 46 and the rotation sensor 47. That is, the cycle of the rising portion Z1a of the waveform Z1 of the detection result of the rotation sensor 46 and the cycle of the rising portion Z2a of the waveform Z2 of the detection result of the rotation sensor 46 differ depending on the reduction ratio of the speed reducer 36. Therefore, when the periodic ratio of the rising portions Z1a and Z2a is different from the reduction ratio of the speed reducer 36, the determination unit 51a can determine that an abnormality has occurred in the speed reducer 36.

As described above, in the monitoring device 40 of the present embodiment, the determination unit 51a is a vertical shaft pump based on the detection results of the two vibration detectors 42A and 42B and the one rotation sensor 46 without performing complicated calculations. The timing of inspection or parts replacement of 10 can be easily determined. Further, since the monitoring device 40 is arranged in a portion of the rotary shaft 21 protruding outward from the pump casing 12, it can be installed in the existing vertical shaft pump 10 and can be installed only at the periodic inspection period. Therefore, the convenience of the administrator of the vertical shaft pump 10 can be improved.

The pump monitoring device 40 of the present invention is not limited to the configuration of the above embodiment, and various changes can be made.

For example, the vibration detectors 42A and 42B that detect the vibration of the rotating shaft 21 are not limited to the configuration including the pair of vibration sensors 44A, 45A and 44B, 45B, and may be changed as necessary. The rotation sensors 46 and 47 are not limited to the optical rotation angle sensor, and may be changed as needed.

The vibration detectors 42A and 42B and the rotation sensor 46 may be arranged inside the pump casing 12, or only a part thereof may be arranged inside the pump casing 12, and the arrangement may be changed as necessary. It is possible.

The determination of the shaft vibration trajectories T1 and T2 by the determination unit 51a may be performed based on the detection result of only one rotation of the rotating shaft 21, or based on the average value of the detection results of a plurality of rotations of the rotating shaft 21. You may go. The rotation sensor 47 that detects the rotation angle of the output shaft 31 may not be used.

The pump monitoring device 40 is not limited to the vertical shaft pump 10, and can be applied to any type of pump as long as it has a rotating shaft extending in the vertical direction, and the same operation and effect can be obtained. can. Further, the pump monitoring device 40 may be applied not only to the pump used in the two-bed building but also to the pump used in the one-bed building.

1 ... Bottom surface 2 ... Pump floor 3 ... Motor floor 4 ... Water absorption tank 5 ... Pump room 6 ... Control room 10 ... Vertical shaft pump 12 ... Pump casing 13 ... Pumping pipe 14 ... Straight pipe 15 ... Vane casing 16 ... Bellmouth 17 ... Discharge Pipe 18 ... Discharge elbow 19 ... Water supply pipe 21 ... Rotating shaft 22 ... Main shaft 23 ... Bearing 24 ... Drive shaft 25 ... Coupling 27 ... Impeller 30 ... Motor 31 ... Output shaft 32a-32c ... Intermediate shaft 33A, 33B ... Cup Ring 34 ... Centrifugal clutch 36 ... Reducer 40 ... Monitoring device 42A, 42B ... Vibration detector 43 ... Mounting frame 44A, 44B ... First vibration sensor 45A, 45B ... Second vibration sensor 46 ... Rotation sensor 47 ... Rotation sensor 48 ... Mounting frame 49 ... Slit 51 ... Controller 51 ... Judgment unit (judgment means)
52 ... Monitor T1, T2, T3 ... Trajectory

Claims (5)

A rotation axis that extends in the vertical direction,
The bearing arranged on the lower end side of the rotating shaft and
A prime mover with an output shaft and
A speed reducer that connects the tip of the output shaft and the upper end of the rotating shaft and transmits the rotation of the output shaft to the rotating shaft.
It is a monitoring device for pumps equipped with
A first rotation sensor arranged on the rotation axis and detecting that the rotation axis has rotated once,
The vibration of the rotating shaft, which is arranged at the first position above the bearing of the rotating shaft and corresponds to the distance between the rotating shaft and the rotating shaft at the first position, is generated during one rotation of the rotating shaft. The first vibration detecting means for detecting a plurality of vibrations, and
Vibration of the rotating shaft, which is arranged at a second position of the rotating shaft above the bearing and below the first vibration detecting means, and corresponds to the distance between the rotating shaft and the rotating shaft at the second position. A second vibration detecting means for detecting a plurality of vibrations while the rotating shaft makes one rotation,
A second rotation sensor arranged on the outer circumference of the output shaft and detecting that the output shaft has made one rotation,
Based on the detection results of the first vibration detecting means, the second vibration detecting means, and the first rotation sensor, the loci of the shaft vibration of the rotating shaft at the first position and the second position are determined, respectively. Then, the locus of the shaft vibration of the rotating shaft in the bearing is determined based on these determination results, while the deceleration is based on the detection results of the first rotation sensor and the second rotation sensor. A pump monitoring device that provides a means of determining an abnormality in the machine . The determination means is a determination result of the shaft vibration locus of the rotation shaft at the first position and the second position, a distance from the upper end of the rotation shaft to the first vibration detection means, and the first vibration detection means. The first aspect of the present invention, wherein the locus of the shaft vibration of the rotating shaft in the bearing is determined based on the distance from the second vibration detecting means to the second vibration detecting means and the distance from the second vibration detecting means to the bearing. Pump monitoring device. The rotary shaft is rotatably arranged in the pump casing so that the lower end side is located in the pump casing and the upper end side penetrates the pump casing and protrudes to the outside.
The first or second aspect of claim 1 or 2, wherein the first vibration detecting means, the second vibration detecting means, and the first rotation sensor are arranged in a portion of the rotating shaft protruding outward from the pump casing. Pump monitoring device. The first vibration detecting means and the second vibration detecting means are a non-contact type first vibration sensor and non-contacting first vibration sensors arranged at intervals of 90 degrees around the axis of the rotation axis with respect to the first vibration sensor. The pump monitoring device according to any one of claims 1 to 3, further comprising a contact-type second vibration sensor. The first rotation sensor arranged on the rotation axis extending in the vertical direction detects that the rotation axis has rotated once, and at the same time, it detects that the rotation axis has rotated once.
The distance between the rotating shaft by the first vibration detecting means and the second vibration detecting means arranged above the bearing arranged on the lower end side of the rotating shaft and at intervals above and below the rotating shaft. A plurality of vibrations of the rotating shaft corresponding to the above are detected while the rotating shaft makes one rotation, respectively.
Based on the detection results of the first vibration detecting means, the second vibration detecting means, and the first rotation sensor, the determining means first arranges the first vibration detecting means and the second vibration detecting means. The locus of the shaft vibration of the rotating shaft at the position and the second position is determined, respectively, and the locus of the shaft vibration of the rotating shaft in the bearing is determined based on these determination results .
A second rotation sensor arranged on the outer circumference of the output shaft of the prime mover detects that the output shaft has made one rotation, and detects that the output shaft has made one rotation.
Based on the detection results of the first rotation sensor and the second rotation sensor, the determination means further connects the tip of the output shaft of the prime mover to the upper end of the rotation shaft of the output shaft. A pump monitoring method for determining an abnormality in a speed reducer that transmits rotation to the rotating shaft .

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