JPH04369454A - Diagnosing apparatus for body of rotation - Google Patents

Abstract

PURPOSE:To quantitavely analyze a body of rotation and diagnose it highly accurately by providing a rotating pulse meter and a bearing thermometer, a displacement converter, a degree analyzer for analyzing vibration vectors, a dangerous speed analyzer, a rotation center analyzer, etc. CONSTITUTION:Each rotation axis 1a of a rotation body 1 is freely rotatably supported on each bearing 2, while a plurality of axial displacement sensors 3a to 3c are attached to a static member so as to detect axial displacement along an outer periphery of the rotation body 1 and the rotation axis 1a. A rotation pulse meter 4 and a bearing thermometer 5 are added to each bearing 2, while the pulse meter 4 detects the number of rotations by counting marks or the like placed on the rotation axis 1a. The pulse meter 4 is connected to a degree analyzer 6 and a bearing characteristics analyzer 7 while the thermometer 7 is connected to the analyzer 7. The analyzer 6 and a rotation center analyzer 11 are connected to the sensors 3a to 3c. A dangerous speed analyzer 13 is connected to the analyzer 6, and the analyzer 13 estimates a dangerous speed of a rotation body 1 of interest. A bearing characteristics analyzer 14 analyzes and evaluates bearing characteristics by means of vibration response analysis based on the dangerous speed of the rotation body 1 and an axial displacement signal.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating body diagnostic device used for analyzing and diagnosing the cause of an abnormality or a sign of abnormality in a rotating body used in, for example, a rotating electric machine or a rotary pump.

0002

[Prior Art] Conventionally, a rotating body diagnostic device used when an abnormality or a sign of abnormality occurs in this type of rotating body analyzes vibration data such as measured shaft displacement signals to determine the vibration level and vibration. Qualitative analysis of phenomena occurring in the rotating body is performed by analyzing and evaluating combinations of states and change trends for evaluation parameters such as vectors and maximum amplitudes.

0003

[Problems to be Solved by the Invention] However, in the above-mentioned rotating body diagnostic device that uses qualitative analysis of what occurs in a rotating body, it is possible to identify the cause of an abnormal event that occurs by using vibration data and the cause of the abnormality in advance. However, it is difficult to estimate the subsequent deterioration tendency (deterioration behavior) and make an accurate analysis and diagnosis.

[0004] In particular, the above-mentioned rotating body diagnostic equipment that qualitatively analyzes occurrences in the rotating body makes it difficult to distinguish between abnormalities on the bearing side and abnormalities on the rotating body side when analyzing and diagnosing abnormalities based on vibration data of the rotating body. be.

The present invention has been made in view of the above-mentioned circumstances, and calculates the critical speed of the rotating body from the vibration characteristics (displacement/phase) caused by the displacement of the bearing, and calculates the bearing characteristics (rigidity,
Damping) is calculated and compared with the bearing characteristics determined by numerical analysis from the rotating body's rotation speed, eccentricity, and bearing shape to estimate abnormalities in bearing shape and viscosity reduction, and to identify abnormalities or signs of abnormalities in the rotating body. It is an object of the present invention to provide a rotating body diagnostic device that can quantitatively analyze and evaluate the cause of the occurrence of the problem and diagnose the rotating body with high accuracy.

[0006]

[Means for Solving the Problems] The present invention includes a rotating body supported by a bearing, a plurality of shaft displacement sensors, a rotational pulse meter, and a bearing thermometer attached to the outer periphery of the rotary body, and each shaft displacement sensor Each displacement transducer is connected to each displacement transducer, and an order analyzer is connected to each displacement transducer to analyze the vibration vector of the rotating body based on the shaft displacement signal detected by each of the shaft displacement sensors and the pulse detection signal of the rotary pulsometer. A critical speed analyzer that analyzes the critical speed of the rotating body from the vibration vector is connected to this order analyzer, and this critical speed analyzer performs measurements corresponding to the vibration response analysis based on the critical speed and the shaft displacement signal. Connect a bearing characteristic analyzer to analyze bearing characteristics,
A rotation center analysis device that analyzes the eccentricity of the bearing based on the displacement signals of each displacement transducer is connected, a bearing characteristic analysis device equipped with bearing shape data is connected to this rotation center analysis device, and the bearing characteristic analysis is performed. A bearing characteristic comparator is connected to the device and the bearing characteristic analysis device to compare each characteristic of the two,
This bearing characteristic comparator is connected to a display device that displays the characteristics.

[0007]

[Operation] The present invention changes the rotational speed of the rotating body, analyzes the vibration vector of the rotating body using an order analyzer from the axis displacement signal and pulse detection signal of the rotating body, and uses the vibration vector from the critical speed analyzer. Calculate the critical speed at each rotational speed from multiple vibration vectors of high rotational orders obtained from the order analyzer to determine bearing characteristics, and when abnormalities or signs of abnormality occur in the rotating body, quantitatively analyze the cause. Based on this critical speed and shaft displacement signal, vibration response analysis is performed using a bearing characteristic analyzer to calculate the bearing characteristics based on the vibration data, and on the other hand, the amount of eccentricity of the bearing is calculated from the shaft displacement signal using a rotation center analyzer. Then, the bearing characteristics are calculated using a bearing characteristic analysis device equipped with bearing shape data based on the eccentricity, the rotation speed based on the pulse detection signal, and the bearing temperature, and the bearing characteristics based on the vibration data and the bearing characteristics obtained analytically are calculated. A bearing characteristic comparator estimates the abnormality that has occurred in the bearing, displays the results on a display device, and performs highly accurate diagnosis.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

In FIGS. 1 and 2, reference numeral 1 denotes a rotating body used, for example, in a rotating electrical machine or a rotary pump, and each rotating shaft 1a of this rotating body 1 is rotatably supported by each bearing 2. A plurality of shaft displacement sensors 3a, 3b, and 3c are attached to a stationary member around the outer periphery of the rotating body 1 and the rotating shaft 1a so as to detect shaft displacement. Further, each of the bearings 2 is provided with a rotation pulse meter 4 and a bearing thermometer 5, and the rotation pulse meter 4 detects the number of rotations by counting marks etched on the rotation shaft 1a. It looks like this. Further, the rotational pulse meter 4 is connected to the order analyzer 6 and the bearing characteristic analyzer 7 via a pulse converter 8, and the bearing thermometer 5 is connected to the bearing characteristic analyzer 7 via a temperature converter 9. connected. Furthermore, bearing shape data 10 is connected to the bearing characteristic analysis device 7, and this bearing shape data 10 is inputted with previously predicted operating conditions and bearing shape data. Reference numeral 7 can search the bearing characteristic data stored in the bearing shape data 10.

[0010] It should be noted that it is necessary to confirm in advance that the results of the analysis by the bearing characteristic analyzer 7 sufficiently match the normal state. Furthermore, the operating conditions used for analysis or search include the eccentricity of the rotating shaft 1a, the rotation speed, and the bearing temperature. Furthermore, the amount of eccentricity of the rotating shaft 1a is calculated by averaging the shaft displacement signals from the respective shaft displacement sensors 3a, 3b, and 3c using a rotation center analyzer 11, which will be described later.

On the other hand, each axis displacement sensor 3a, 3b, 3
c, the order analyzer 6 and rotation center analyzer 11 are connected via displacement converters 12a, 12b, and 12c, and the order analyzer 6 calculates the shaft displacement from the shaft displacement signal and the rotation pulse signal. This is a device that analyzes vibration vectors of arbitrary orders included in vibrations, and uses frequency analysis or vector filters.

[0012] Here, the term "arbitrary order" refers to a frequency that is an integral multiple of the rotational synchronous frequency, assuming that the rotational synchronous frequency that synchronizes with the rotational speed is the first order (1N). That is, for example,
The X-th order indicates a frequency that is X times the rotation synchronous frequency.

Therefore, the vibration vector Vx of arbitrary order X (XN) is a vector quantity consisting of the amplitude Ax of the vibration component and the phase difference θx with the rotation pulse signal.

[0014] Expressing this in the formula, Vibration vector Vx = (Ax・θx) It is.

Generally, when the rotational speed of the rotating body 1 changes during starting, stopping, or rotational speed control, the vibration vector changes in accordance with the vibration characteristics of the rotating body 1, such as critical speed.

Therefore, when a certain order passes through the critical speed of the rotating body, its vibration vector draws a trajectory as shown in FIG. Therefore, the critical speed of the rotating body 1 can be estimated by analyzing the vibration vector whose order passes through the critical speed with respect to a change in the rotational speed.

On the other hand, a critical speed analyzer 13 is connected to the order analyzer 6 so as to analyze the critical speed of the rotating body 1 from the vibration vector. In other words, the critical speed analysis device 13 is a device that estimates the critical speed of the target rotating plate 1, and the critical speed analysis device 13 is a device that estimates the critical speed of the target rotating plate 1.
), R/60 (
The system is configured to be able to estimate critical speeds that exist up to the frequency band (Hz).

[0018] Normally, the critical speed of the rotating body 1 is:
It is higher than the rotation synchronous frequency, and as shown in the graph of the frequency of the rotating body and the rotation order in Figure 2, a vibration vector with a low order such as 1N or 2N does not pass the critical speed, so the critical speed is difficult to estimate.

Therefore, the order analyzer 6 can estimate the critical speed of the rotary plate 1 by obtaining a high-order vibration vector that passes through the critical speed, and can also estimate critical speeds at higher frequencies. It is set up so that you can

Therefore, as shown in the graph of frequency and rotation order of the rotating body in FIG. 2, for example, for a vibration vector of 10N, R/60 (Hz) of 1N is 10 times It is possible to grasp the vibration characteristics up to (Hz), and it is possible to sufficiently estimate the critical speed.

On the other hand, the critical speed analyzer 13 includes:
A bearing characteristic analyzer 14 is connected, and the bearing characteristic analyzer 14 analyzes the measured bearing characteristics in response to a vibration response analysis based on the connection critical speed and the shaft displacement signal.

That is, the bearing characteristic analyzer 14 analyzes the bearing characteristics by vibration response analysis based on the critical speed of the rotating body 1 obtained by the critical speed analyzer 13 and the shaft displacement signal representing the vibration response of the rotating body 1. It is a device for analysis and evaluation.

[0023]The analytical model for vibration response analysis is as follows:
The structure of the stationary member and the rotating body 1 is constructed by modeling structural elements such as beams, and the bearing 2 is modeled using a spring or the like. Further, a structure can be modeled from a design drawing, and the bearing 2 can be analyzed and modeled based on its bearing shape and operating conditions.

[0024] As described above, the structure is relatively easy to model, and there are relatively few abnormal events that change the critical speed, except for cracks, corrosion, and the like. On the other hand, the characteristics of the bearing 2 need to be verified against analysis results, and the characteristics change significantly due to failure. Therefore, for the structure, a vibration response analysis is performed using a model verified at the initial stage of operation, using the characteristics of the bearing 2 (bearing stiffness) as a parameter, and the resulting critical speed is obtained by the critical speed analyzer 13. The analysis is repeated until the critical speed is approximately the same as the calculated critical speed. As a result, the characteristics of the bearing 2 can be inferred from the measured shaft displacement vibration.

At the same time, the bearing characteristic analysis device 7 calculates, based on the operating conditions and the input data of the bearing shape data 10,
It is obtained by searching the bearing characteristic data for each operating condition as the characteristic when the bearing 2 is normal.

Next, as described above, each of the displacement transducers 1
2a, 12b, and 12c include the rotation center analyzer 11
is connected, and this rotation center analyzer 11 analyzes the amount of eccentricity of the bearing 2 based on displacement signals from the respective displacement transducers 12a, 12b, and 12c. or,
A bearing characteristic analyzer 7 having bearing shape data 10 is connected to this rotation center analyzer 11, and this bearing characteristic analyzer 7 and the bearing characteristic analyzer 14 compare each characteristic of the two. A bearing characteristic comparator (also referred to as a bearing characteristic comparison device) 15 is connected thereto. Furthermore, this bearing characteristic comparator 15 includes a display device 16 for displaying the characteristics.
is connected to the rotating body 1, and this display device 16 is connected to the rotating body 1.
When an abnormality or a symptom of an abnormality occurs, the cause is quantitatively analyzed and evaluated, and the diagnosis is displayed with high accuracy.

The operation of the present invention will be explained below.

Therefore, by changing the rotational speed of the rotary body 1 as the object to be measured according to the present invention, the rotational body 1 is
The vibration vector of the rotating body 1 is analyzed by the order analyzer 6 based on the axial displacement signal and pulse detection signal of the rotating body 1. Then, a critical speed is calculated from this vibration vector by the critical speed analyzer 13, bearing characteristics are determined, and the critical speed of the rotating body 1 is analyzed and evaluated.

Next, a vibration response analysis is performed by the bearing characteristic analyzer 14 based on the critical speed and the shaft displacement signal, and bearing characteristics are calculated based on the vibration data. On the other hand, the rotational center analyzer 11 calculates the eccentricity of the bearing 2 from the shaft displacement signals of the respective shaft displacement sensors 3a, 3b, and 3c, and calculates the eccentricity and the rotational speed and bearing temperature based on the pulse detection signal of the rotational pulse meter 4. The bearing characteristics are calculated by the bearing characteristic analysis device 7 equipped with the bearing shape data 10 based on the vibration data, and the abnormality occurring in the bearing 2 is estimated by the bearing characteristic comparator 15 using the bearing characteristics based on the vibration data and the bearing characteristics obtained analytically. The result is then displayed on the display device 16.

[0030] In this manner, the present invention enables highly accurate diagnosis by quantitatively analyzing and evaluating the cause when an abnormality or a sign of abnormality occurs in the rotating body 1.

[0031]

As described above, according to the present invention, a rotating body is supported on a bearing, and a plurality of shaft displacement sensors, rotational pulse meters, and bearing thermometers are attached to the outer periphery of the rotating body, and each of the shafts is Order analysis in which each displacement transducer is connected to a displacement sensor, and the vibration vector of the rotating body is analyzed using the shaft displacement signal detected by each axis displacement sensor and the pulse detection signal of the rotational pulsometer. A critical speed analyzer that analyzes the critical speed of the rotating body from the vibration vector is connected to this order analyzer, and this critical speed analyzer supports vibration response analysis based on the critical speed and the shaft displacement signal. A bearing characteristic analyzer is connected to each of the displacement transducers to analyze the measured bearing characteristics, and a rotation center analyzer is connected to each of the displacement transducers to analyze the eccentricity of the bearing based on the displacement signal. A bearing characteristic analyzer equipped with the data is connected, a bearing characteristic comparator for comparing each characteristic of the two is connected to this bearing characteristic analyzer and the bearing characteristic analyzer, and the characteristics are displayed on this bearing characteristic comparator. Since a display device is connected, it is not only possible to quantitatively analyze and evaluate the causes of abnormalities or signs of abnormalities in the rotating body and diagnose them with high accuracy, but also to identify abnormalities on the bearing side and abnormalities on the rotating body side. It has excellent effects such as being able to effectively and appropriately diagnose judgments.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a rotating body diagnostic device of the present invention.

FIG. 2 is a graph showing the relationship between the frequency and rotational order of the rotating body of the present invention.

FIG. 3 is a diagram for explaining the action of the rotating body of the present invention when passing through a critical speed.

[Explanation of symbols]

1 Rotating body 2 Bearings 3a, 3b, 3c Shaft displacement sensor 4 Rotation pulse meter 5 Bearing thermometer 6 Order analyzer 7 Bearing characteristic analyzer 10 Bearing shape data 11 Center of rotation analyzer 12a, 12b, 12c Displacement converter 13 Critical speed Analyzer 14 Bearing characteristic analyzer 15 Bearing characteristic comparator 16 Display device

Claims (1)

[Claims] [Claim 1] A rotating body supported by a bearing, a plurality of shaft displacement sensors, a rotation pulse meter, and a bearing thermometer attached to the outer periphery of the rotary body, and displacement converters connected to each of the shaft displacement sensors. an order analyzer that is connected to each of the displacement transducers and analyzes the vibration vector of the rotating body based on the shaft displacement signal detected by each of the shaft displacement sensors and the pulse detection signal of the rotary pulse meter, and this order analyzer. A critical speed analyzer is connected to the device and analyzes the critical speed of the rotating body from the vibration vector, and a critical speed analyzer is connected to the critical speed analyzer and measures bearing characteristics in response to vibration response analysis based on the critical speed and the shaft displacement signal. a bearing characteristic analyzer to analyze; a rotation center analyzer connected to each of the displacement transducers to analyze the eccentricity of the bearing based on displacement signals; and a bearing characteristic connected to the rotation center analyzer and provided with bearing shape data. an analysis device,
The present invention is characterized by comprising a bearing characteristic comparator connected to the bearing characteristic analysis device and the bearing characteristic analysis device to compare the respective characteristics of the two, and a display device connected to the bearing characteristic comparator to display the characteristics. Rotating object diagnostic equipment.