JPS63111599A - Automatic spindle deformation monitor for hydraulic machine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is aimed at preventing abnormalities such as deformation of the main shaft of hydraulic machines such as water turbines or pump water turbines before they cause a major accident. This invention relates to an automatic monitoring device for main shaft deformation of hydraulic machinery that can detect the deformation of a hydraulic machine.

(Prior Art) In hydraulic machines such as water turbines or pump-turbines, especially those with high head and large capacity, the components are capable of withstanding high speeds, high pressures, and high stresses, and are also sufficiently resistant to shaft vibration and stationary motion. required to obtain.

By the way, the reliability of the main shaft, which is the center of rotation in hydraulic machinery, is paramount because if an abnormality occurs, it may cause vibrations in the shaft system and damage to bearings, etc., and cause a major accident. Despite being requested as a priority, monitoring has not been carried out to date.

(Problem to be solved by the invention) When this spindle accident occurs, it takes a long time to recover, and during that time the hydraulic power machine is stopped, which reduces its operating rate and improves productivity. It has become a bottleneck. In particular, damage to the main shaft of a large-capacity hydraulic machine will result in a huge loss. Therefore, when an abnormal state or initial damage occurs to such a main shaft, it is very important to detect it and take necessary measures before it develops into a major main shaft accident.

The purpose of the present invention is to detect the state of the main shaft during operation based on shaft runout, bearing temperature, and bearing oil film thickness, and to constantly monitor the main shaft deformation in the hydraulic 1jI range without stopping the machine and making precise measurements. The purpose of the present invention is to provide an automatic monitoring device.

(Structure of the Invention) (Means for Solving the Problems) In order to achieve the above-mentioned object, the main shaft deformation automatic monitoring device for hydraulic machinery of the present invention comprises a main shaft skirt, a bearing metal, and a bearing oil tank housing them. In hydraulic machinery, a sensor is attached to the bearing metal to detect the bearing temperature and the bearing oil film thickness, a sensor is attached near the bearing oil tank to detect the shaft runout of the rotating shaft, and the output signals of these sensors are An alarm circuit is provided which is compared with a preset set value and activated if any of the output signals exceeds the set value.

(Function) If any of the bearing temperature, bearing oil film, and shaft runout exceeds a set value, an alarm circuit is activated, and the spindle deformation is automatically monitored based on the results of logical operations here.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

Figure 2 is a vertical cross-sectional view of the main parts of a hydraulic machine to which the present invention is applied. Water flowing from an upper pond (not shown) is transported from a casing (not shown) of a water wheel or pump turbine to a speed ring (not shown). ), and flows into a pressure chamber consisting of an upper cover 1 and a lower cover 2. Guide vanes (not shown) are arranged at the entrance of the pressure chamber, and the flowing water whose flow rate is adjusted by the guide vanes acts on the runner 3, and the power generation unit connected to the runner 3 and the main shaft 4 via the main shaft 4 is generated. rotating a generator or generator (not shown). The water that has passed through the runner 3 passes through a draft tube 5 and is discharged to a lower pond (not shown).

On the other hand, during water exchange operation using the pump turbine, water from the lower pond is pumped up through the draft tube 5 by the runner 3 driven by the generator motor, contrary to the above, and from the pressure chamber to the stay ring, casing, and penstock (not shown). )
After that, the water is exchanged to the upper pond.

A main shaft skirt 6 and a bearing metal 7 provided on the main shaft 4, and a bearing oil tank 8 for housing them are installed.

In the embodiment shown in FIG. 2, a bearing oil film thickness detection sensor S1 and a bearing temperature detection sensor S2 are installed on the bearing metal 7 to detect the oil film thickness between the spindle skirt 6 and the bearing metal 7 and the temperature of the bearing metal 7. Detect each. Further, a shaft runout detection sensor S3 is installed above the bearing oil tank 8 to detect shaft runout of the main shaft 4.

One or more of the above-mentioned sensors 81 to S3 are installed at appropriate positions, but in the following description,
For convenience, the case where each sensor is one will be described.

FIG. 1 shows an embodiment of the processing/display circuit for the signals detected by the above-mentioned sensors 81 to S3. The oil film thickness signal 20 detected by the bearing oil film thickness detection sensor S1 is The bearing oil film thickness abnormality signal 23 is input to the comparator 30 and compared with a set value, and if it is smaller than the set value, a bearing oil film thickness abnormality signal 23 is output.

The bearing temperature signal 21 detected by the bearing temperature detection sensor S2 is input to the bearing temperature comparator 31 and compared with a set value, and if it is larger than the set value, a bearing temperature abnormality signal 24 is output.

The shaft runout signal 22 detected by the shaft runout detection sensor S3 is input to the spindle runout comparator 32 and compared with a set value, and if larger than the set value, a spindle runout abnormal signal 25 is output.

These abnormality signals 23, 24, and 25 are input to the alarm circuit 40, and the alarm circuit 40 performs a logical operation on the input, and if a logical operation result that indicates that the main shaft of the hydraulic machine is abnormal is issued, an alarm for the main shaft abnormality of the hydraulic machine is issued. The signal 50 is output toward the alarm device 60 and simultaneously output toward the abnormality indicator 70. The abnormality signal 23.24.25 from the comparator 30.31.32 is also input to the abnormality indicator 70, and the abnormal state and abnormal location are displayed.

The above-mentioned alarm circuit 40 includes a NOT circuit 4 as shown in FIG.
0a and an AND circuit 40b.

The NOT circuit 40a does not output the normal signal 26 if the bearing oil film thickness abnormal signal 23 is input. Further, the AND circuit 40b outputs the abnormal signal 23.24 and the NOT circuit 4.
When all the normal signals 26 of 0a are input, a hydraulic machine main shaft abnormality alarm signal @50 is output.

FIG. 4 shows an embodiment in which a frequency analyzer 80 and a recording device 90 are added to the circuit shown in FIG.

In this example, the shaft runout signal 22 from the main shaft shaft runout detection sensor S3 is input to the frequency analyzer 80, where it is frequency analyzed and becomes a shaft runout rotation synchronous frequency signal 27 synchronized with the rotation speed of the hydraulic machine. 32. In this case, the set value of the comparator 32 is changed to a value for a signal at the rotation synchronous frequency.

In addition, the recording device @90 includes a bearing oil film thickness detection sensor S.
1. Bearing temperature detection sensor S2, shaft runout detection sensor S
Oil film thickness signal from 3.20. The bearing temperature signal 21, the shaft runout signal 22, the shaft tilt rotation synchronization frequency signal 27 from the frequency analyzer 80, and the abnormal signals 23 to 25 from the comparators 30 to 32 are constantly input and recorded.

The other circuit configuration and operation in FIG. 4 are the same as in FIG. 2.

Next, the operation of the apparatus of the present invention configured as described above will be explained.

If an abnormality occurs in the shaft system of the hydraulic machine due to causes such as deformation of the main shaft, misalignment of the building, poor alignment, poor centering, wear of the bearing pivot, or loosening of the coupling bolt, the shaft runout of the hydraulic machine will occur. This appears as an abnormality in bearing temperature. Therefore, by monitoring the shaft runout of the hydraulic machine and the temperature of the bearing metal, it is possible to detect an abnormality in the main system of the hydraulic machine. However, abnormal deformation of the main shaft of a hydraulic machine, abnormal axis misalignment, and abnormality of the main bearing device both cause abnormal shaft runout and abnormal bearing temperature of the hydraulic machine. It is not possible to determine whether there is an abnormality in deformation, misalignment, or main bearing device of the hydraulic machine's main shaft by simply monitoring the temperature of the hydraulic machine.

However, if the main bearing device is normal and there is no axis misalignment, and only the main shaft deformation of the hydraulic machine occurs, the shaft runout of the hydraulic machine and the main bearing temperature will be abnormal, but it will be possible to take pictures using the bearing as the fulcrum. , there is no abnormality in the thickness of the bearing oil film on the main bearing.

Therefore, by monitoring the shaft runout of the hydraulic machine, the temperature of the main bearing metal, and the thickness of the bearing oil film, it is possible to detect abnormal deformation of the main shaft of the hydraulic machine before it leads to a serious accident.

Therefore, in the present invention, as shown in FIG. 1, the oil film thickness signal 20 from the bearing oil film thickness detection sensor $1, the bearing temperature signal 21 from the bearing temperature detection sensor S2, and the shaft runout signal from the shaft runout detection sensor S3 are used. 22 and a comparator 30.
31 and 32, and when the input is greater than the set value, a bearing oil film thickness abnormality signal @23, a bearing temperature abnormality signal 24, and a spindle shaft runout abnormality signal 25 are output.

The alarm circuit 40 receives a bearing temperature abnormality signal 24 and a spindle shaft runout abnormality signal 25 simultaneously, and a bearing oil film thickness abnormality signal @2.
If 3 is not input, it means that the main shaft of the hydraulic machine has been deformed, so the main shaft abnormality alarm signal 50 of the hydraulic machine is output to the alarm 60, and necessary necessary warning signals are sent to the alarm 60 before it spreads to a serious accident. Measures can be taken.

As described above, the oil film thickness signal 20. bearing temperature signal 21,
Deformation of the main shaft of a hydraulic machine can be detected by monitoring the shaft runout signal 22, but with the configuration shown in FIG. 4, abnormality can be detected with even greater accuracy.

In other words, if there is an abnormality in deformation of the main shaft of a hydraulic machine, shaft runout will occur due to unbalanced force every rotation of the main shaft of the hydraulic machine, so the shaft runout signal 2 will be generated in the frequency component periodic to this rotation.
2 appears prominently.

Therefore, if the frequency analyzer 80 analyzes the shaft runout signal 22 from the shaft runout detection sensor S3, outputs the shaft runout rotation synchronization frequency multiplied by @27, and compares this signal with the set value in the comparator 32, noise can be detected. It is possible to detect and monitor the progress of abnormalities with high accuracy. In addition, by recording data of various signals 20 to 25 and 27 using the recording device @90, it becomes possible to check the propagation process of damage caused by deformation of the main shaft of the hydraulic machine, and each comparator 30 to 3
It is also possible to optimize the setting value of 2 to enable the detection of very small abnormalities, and to collect data to improve monitoring of simple configurations.

In the above-described embodiment, by monitoring the main shaft runout, bearing temperature, and oil film thickness of the hydraulic machine, the presence or absence of abnormal deformation of the main shaft of the hydraulic machine can be constantly monitored without stopping or disassembling the machine. Furthermore, if the rotational synchronization frequency component of the shaft system is monitored, more accurate monitoring can be achieved. In general, by checking the progress of an abnormality using a recording device, it is possible to detect an abnormality at an early stage.

The present invention is not limited to the embodiments described above, but can also be realized by the circuits shown in FIGS. 5 and 6.

In FIG. 5, T1 to Tn are I explained with reference to FIG.
NIJi wear detection sensors S3, U1 to Un are vibration sensors, displacement sensors, and temperature sensors similar to the bearing oil film thickness detection sensor S1 and the bearing temperature detection sensor 82 explained with reference to FIG. A plurality of them are arranged and fixed at predetermined locations on the device.

The outputs of these (dynamic sensors T1 to Tn) are input to a frequency analyzer 80 consisting of an FFT analyzer, etc., and are used to calculate the rotation synchronous frequency component of the main shaft of the hydraulic machine, that is, N/60 Hz in the case of N rotations per minute. The frequency is analyzed into components.

The signals from the displacement sensor and the temperature sensor and the signal frequency-analyzed by the frequency analyzer are sent to a judgment circuit 1.
00 and is also sent to the recording device 90. The determination circuit 100 is set with the bearing oil film thickness, bearing temperature, and rotational synchronization frequency component of shaft runout that should be determined to be abnormal, and each sensor U1 to Lln and the frequency analyzer 8
A comparison is made with the detected value starting from 0.

If this detected value exceeds the set value, the detected value signal is sent to the combination pattern creation circuit 110, and the detection unit abnormality indicator 1-2 corresponding to the detection unit of the signal determined to be abnormal.
0, and displays such as "minimum bearing oil film thickness,""excessive hydraulic machine shaft runout," and "excessive bearing device temperature."

FIG. 6 shows an example of the configuration of the combination pattern creation circuit 110. In the figure, X1 indicates the connection point with the discrimination circuit 100 that discriminates whether the signal from the shaft runout detection sensor S3 is abnormal or normal, and x2 indicates the connection point. The connection point with the discrimination circuit 100 which discriminates whether the signal from the bearing temperature detection sensor S2 is abnormal or normal, and x3 indicates the discrimination which discriminates whether the signal from the bearing oil film thickness detection sensor $1 is abnormal or normal. The mating contacts with the circuit 100 are shown.

The signals of the connecting contacts x3 are input to the NOT circuit 40C, and the signals of the connecting contacts X1. The signal of X2 and the output signal of NOT circuit 40G are input to AND circuit 40d, and A
The output signal of the ND circuit 40d is output from the output contact Y.

Therefore, a signal is output to output contact Y when the rotation synchronous frequency component of the shaft runout of the hydraulic machine exceeds the set value, the bearing device temperature exceeds the set value, and the bearing oil film thickness is the average value. is.

When an output is generated at the output contact Y, this signal is guided to an alarm device 60 consisting of a buzzer or the like to activate it, as shown in FIG. 5, and is also guided to an abnormality indicator 70 to indicate the occurrence of an abnormality. do. The recording device 90 also includes signals from the displacement sensors and temperature sensors U1 to Un, signals from the frequency analysis device 8o, and a combination pattern creation circuit 1.
The signals from the 10 output contacts Y are recorded over time.

In this embodiment, the same effect as explained with reference to FIG.
It can be easily determined by 0.

Furthermore, the frequency analysis device is not limited to the FFT analysis device, but may be configured with a bandpass filter or a comb filter that passes a frequency band within a predetermined range.

The above-mentioned frequency analyzer, comparator, alarm circuit, discrimination circuit,
Similar effects can be achieved by implementing a circuit such as a combination pattern creation circuit using software.

〔Effect of the invention〕

According to the present invention, the following effects can be obtained.

■ The deformation of the main shaft of hydraulic machinery can be constantly monitored, improving reliability.

■ There is no need to stop operation and disassemble the rotating parts of hydraulic machinery to inspect them, unlike conventional methods.

(3) It is possible to significantly reduce the cost, time, and work required to inspect the rotating parts of hydraulic machinery.

(b) It is possible to detect abnormal deformation of the main shaft of hydraulic machinery at an early stage, and prevent it from spreading into a serious accident.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating an electric circuit according to the present invention, FIG. 2 is a longitudinal sectional view illustrating an embodiment of a hydraulic machine to which the present invention is applied, and FIG. 3 is a specific example of the alarm circuit in FIG. 1. 4 is a block diagram showing a modification of the present invention, FIG. 5 is a block diagram showing another embodiment of the invention, and FIG. 6 is a specific example of the combination pattern creation circuit in FIG. 5. It is a block diagram. 1...Top cover 2...Bottom cover 3...
・Runner 4...Main shaft 5...Draft tube 6...Main shaft skirt 7...Bearing metal 8...Bearing oil tank 20...Oil film thickness signal
21...Bearing temperature signal 22...Shaft runout signal 23...Bearing oil film thickness abnormality signal 24...Bearing temperature abnormality signal 25...Spindle shaft runout abnormality 26...Normal signal 27... Shaft runout rotation synchronous frequency signal 30-32...Comparator 40...Alarm circuit 40a-NOT circuit 40b-AND circuit 40
C...NOT circuit 40d...AND circuit 5
0...Spindle abnormality alarm signal 60...Alarm 70.
... Abnormality indicator 80 ... Frequency analyzer 9
0...Recording device 100...Discrimination circuit 1
10...Combination pattern creation circuit 120...Detection unit abnormality indicator Sl...Bearing oil film thickness detection sensor S2...Bearing temperature detection sensor S3...Shaft system deviation detection sensor T1-Tn... Vibration sensor U1~Un...Displacement sensor or temperature sensor x 1
~X3...Connection contact Y...Output contact agent Patent attorney Nori Chika Ken Yudo Hirofumi MitsumataFigure 1 Figure 2 Figure 3

Claims (6)

[Claims] (1) A water wheel or a pump water wheel and a generator or a power generator are arranged on one shaft, directly connected by a flange, etc., and the main shaft skirt provided on the rotating shaft, the bearing metal arranged relatively, and the lubrication In a hydraulic machine supported by a main bearing device that is filled with fluid and is composed of a main shaft skirt and a bearing oil tank that houses a bearing metal, a sensor provided on the main shaft metal detects the bearing temperature, and a sensor that detects the bearing oil film thickness is provided. and a sensor for detecting shaft runout of the rotating shaft near the oil tank, the electrical output signals from these detection sensors are compared with a predetermined setting value, and one of the output signals is determined as the setting value. An automatic main shaft deformation monitoring device for a hydraulic machine, characterized in that it is configured to activate an alarm circuit and transmit an output to an abnormality indicator when a value exceeds a value. (2) The output signals of the shaft runout detection sensor, bearing temperature detection sensor, and bearing oil film thickness detection sensor are compared with the set value in the comparator, and the output of each comparator is input to the abnormality indicator and passed through the alarm circuit. 2. The automatic main shaft deformation monitoring device for a hydraulic machine according to claim 1, wherein the information is input to an alarm. (3) The alarm circuit receives a signal from a comparator based on the output of the main bearing temperature detection sensor that detects the bearing metal temperature of the main bearing device and a signal from a comparator based on the output of the main shaft runout detection sensor that detects the shaft runout of the main shaft. It is composed of an AND circuit that produces an output when the signal is input and an abnormal signal from the comparator based on the output of the bearing oil film thickness detection sensor that detects the bearing oil film thickness of the main bearing device is not input. An automatic main shaft deformation monitoring device for a hydraulic machine according to claim 2, characterized in that: (4) A patent claim configured such that the output from a spindle runout detection sensor that detects spindle runout is input to a frequency analyzer, and a synchronized rotational synchronous frequency component of the hydraulic machine is extracted and input to a comparator. Scope: Automatic main shaft deformation monitoring device for hydraulic machinery according to item 3. (5) Automatic monitoring of main shaft deformation of a hydraulic machine according to claim 4, wherein the output signals from each of the sensors, the frequency analyzer, and the comparator are input to a recording device and recorded over time. Device. (6) A water wheel or a pump water wheel and a generator or a power generator are arranged on one shaft, directly connected by a flange, etc., and the main shaft skirt provided on the rotating shaft, the bearing metal arranged relatively, and the lubrication In a hydraulic machine supported by a main bearing device that is filled with fluid and is composed of a main shaft skirt and a bearing oil tank that houses a bearing metal, a sensor provided on the main shaft metal detects the bearing temperature, and a sensor that detects the bearing oil film thickness is provided. a sensor for detecting the shaft runout of the rotating shaft near the oil tank; a frequency analyzer for inputting the output of the main shaft shaft runout detection sensor for detecting the shaft runout of the main shaft; a sensor for detecting the bearing temperature; a discrimination circuit which inputs the output of the sensor for detecting the bearing oil film thickness and the output of the frequency analyzer and generates an output when these input signals exceed a set value; and a discrimination circuit based on the output of this discrimination circuit. A combination pattern creation circuit that creates a combination pattern, an alarm, an abnormality indicator, and a recording device that are activated by the output of the combination pattern creation circuit, and a detection unit abnormality indicator that inputs the output signal of the discrimination circuit. What is claimed is: 1. An automatic main shaft deformation monitoring device for a hydraulic machine, characterized by comprising: