CN114264366A - Method for monitoring multi-angle vibration components of pump shell of water pump unit - Google Patents

Abstract

The invention relates to a method for monitoring multi-angle vibration components of a pump shell of a water pump unit, which comprises the steps of respectively installing a displacement sensor in the x-axis direction and the y-axis direction of the pump shell of the water pump, testing the decomposition displacement of a water outlet pump at the same time, calculating the angle of the vibration on a polar coordinate, and calculating the vibration frequency by using Fourier transform; and finally, simultaneously drawing the amplitude and the frequency of each vibration in each direction on a two-dimensional polar coordinate graph. According to the invention, the vibration characteristics and the direction of the pump shell of the water pump can be detected for a long time through the two-dimensional graph, so that real-time monitoring is realized.

Description

A method for monitoring the multi-angle vibration components of the pump casing of a water pump unit

technical field

The invention relates to a method for monitoring multi-angle vibration components of a pump casing of a water pump unit, belonging to the field of hydraulic engineering.

Background technique

Spectrum analysis has always been an important means of device failure problem detection. However, using a hand-held or fixed-installed detector for monitoring often results in inaccurate detection results due to the error of the detection position and the inability to construct the correlation of the vibration values in the detection of vertical and horizontal positions. By adopting this patent, the characteristic values of amplitude and frequency of each azimuth at the same time period can be obtained, and the detection accuracy of vibration can be improved.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for monitoring the multi-angle vibration components of the pump casing of the water pump unit in view of the problems existing in the above-mentioned prior art, and to change the problem of judging the vibration orientation by combining vertical and horizontal vibration signals in the traditional single detection.

The purpose of the present invention is to achieve in this way: a method for monitoring the multi-angle vibration components of the pump casing of the water pump unit, which is characterized in that: a displacement sensor is installed on the x-axis and the y-axis direction of the water pump casing, and a displacement sensor is installed at the same time when the water pump is tested. The decomposition displacement of , and then the following formula calculates the angle of this vibration in polar coordinates:

表示角度θ下的振动幅度；dθ：该次振动的角度；dx：该次振动下，x方向传感器测得的该方向下的位移；dy：该次振动下，y方向传感器测得的该方向下的位移；in,

Indicates the vibration amplitude at the angle θ; dθ: the angle of the vibration; dx: the displacement in the direction measured by the sensor in the x direction under the vibration; dy: the direction measured by the sensor in the y direction under the vibration displacement below;

At the same time, the vibration frequency is calculated by Fourier transform;

Finally, the amplitude and frequency of each vibration in each direction are simultaneously plotted on the two-dimensional polar diagram.

The displacement sensor is a vibration sensor.

Each vibration passes through the displacement sensors in the direction of the two vertical coordinate axes on the pump casing. After calculation, the time-domain spectrogram of the angle is firstly generated. After Fourier transform, the frequency-domain spectrogram is obtained and recorded. After the amplitude and frequency of the vibration, the next calculation is performed;

When there are ten vibrations of the same frequency or similar frequency at the same angle, a line covering the amplitude range and marked with the frequency will appear at the angle.

The method of the invention is advanced and scientific. Through the invention, a displacement sensor is installed in the direction of the x-axis and the y-axis of the pump casing to test the decomposition displacement of the pump at the same time, and then the following formula:

The angle of the vibration in polar coordinates can be calculated.

表示角度θ下的振动幅度。同时用傅里叶变换计算出振动频率，在二维极坐标图上同时绘制出各个方向上，各个振动的振幅以及频率。use

represents the vibration amplitude at the angle θ. At the same time, the Fourier transform is used to calculate the vibration frequency, and the amplitude and frequency of each vibration in each direction are simultaneously drawn on the two-dimensional polar diagram.

Beneficial effects:

Obtaining the azimuth of the time-domain frequency-domain spectrum in the pump casing of the pump unit can effectively predict the location and characteristics of the pump failure. The vibration amplitude and frequency orientation are simultaneously reflected on a two-dimensional map, and the vibration characteristics and orientation of the pump casing can be detected for a long time through the two-dimensional map to realize real-time monitoring.

The main purpose of the present invention is to accurately monitor the running state of the water pump by decomposing the overall vibration of the water pump into vibration frequencies and amplitudes at different angles.

With the increasing development of water pump technology, the monitoring of water pump operation status has gradually attracted attention. At present, the existing monitoring ideas mainly use the frequency and amplitude of the vibration signal of the pump unit to preliminarily judge the operation status of the pump. The invention can measure the vibration components at multiple angles of the pump casing of the unit, which can effectively improve the accuracy of the monitoring method.

Description of drawings

1 is a schematic diagram of a displacement sensor arranged vertically in accordance with the present invention;

FIG. 2 is a spectrogram of the present invention recording the amplitude and frequency of multi-angle vibration simultaneously in polar coordinates.

In the picture: 1 impeller, 2 guide vanes, 3 displacement sensors.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and the description of the accompanying drawings.

A method for monitoring the multi-angle vibration components of the pump casing of the water pump unit. A displacement sensor is installed in the x-axis and y-axis directions of the pump casing to test the decomposition displacement of the water pump at the same time, and then the following formula calculates the vibration at the same time. Angle in polar coordinates:

表示角度θ下的振动幅度；dθ：该次振动的角度；dx：该次振动下，x方向传感器测得的该方向下的位移；dy：该次振动下，y方向传感器测得的该方向下的位移；in,

Indicates the vibration amplitude at the angle θ; dθ: the angle of the vibration; dx: the displacement in the direction measured by the sensor in the x direction under the vibration; dy: the direction measured by the sensor in the y direction under the vibration displacement below;

At the same time, the vibration frequency is calculated by Fourier transform;

Finally, the amplitude and frequency of each vibration in each direction are simultaneously plotted on the two-dimensional polar diagram.

also:

(1) The present invention is applicable to all built pumping stations.

(2) The fixed-point multi-angle vibration tester avoids errors caused by different test points and test angles during each test, and can improve the matching accuracy of field test results and fault database data.

(3) The new polar coordinate diagram generation process: each vibration passes through the displacement sensors in the direction of the two vertical coordinate axes on the pump casing. After calculation, the time domain spectrum diagram of the angle is generated first, and then the Fourier transform , obtain the frequency-domain spectrogram, record the amplitude and frequency of the vibration, and perform the next calculation. When there are ten vibrations of the same frequency (similar frequency) at the same angle, a line covering the amplitude range and marked with the frequency will appear at the angle. In this way, it can prevent the frequency from being too fast and cannot be observed by the human eye, and is also conducive to screening periodic vibrations and eliminating noise.

Claims (2)

1. a method for monitoring the multi-angle vibration component of the pump casing of the water pump unit is characterized in that: a displacement sensor is installed on the x-axis and the y-axis direction of the water pump casing, and the decomposition displacement of the water pump at the same time is tested, and then the following formula Calculate the angle of this vibration in polar coordinates:

in,

Represents the vibration amplitude under the angle θ; dθ represents the angle of the vibration; dx represents the displacement in the direction measured by the sensor in the x direction under the vibration; dy represents the direction measured by the sensor in the y direction under the vibration displacement below; At the same time, the vibration frequency is calculated by Fourier transform; Finally, the amplitude and frequency of each vibration in each direction are simultaneously plotted on the two-dimensional polar diagram. 2. a method for monitoring the multi-angle vibration component of the pump casing of a water pump unit according to claim 1, is characterized in that: every vibration is passed through the displacement sensors on the two vertical coordinate axis directions on the water pump casing, through To calculate, first generate the time-domain spectrogram of the angle, and after Fourier transform, obtain the frequency-domain spectrogram, record the amplitude and frequency of the vibration, and perform the next calculation; When there are ten vibrations of the same frequency or similar frequency at the same angle, a line covering the amplitude range and marked with the frequency will appear at the angle.

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