Rubbing position identification device and rubbing position identification method for rotating machine

Patent metadata

Field	Value
Publication number	US-12560472-B2
Application number	US-202218285330-A
Country	US
Kind code	B2
Filing date	Mar 30, 2022
Priority date	Apr 8, 2021
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

The present invention relates to a rubbing position identification device for a rotating machine provided with a fixed part and a rotating part. This device is provided with an AE sensor, an axial vibration sensor and a rubbing position identification unit. In the case of rubbing occurring in the rotating machine, the rubbing position identification unit calculates the AE phase, which corresponds to the peak of an envelope determined on the base of change over time in the AE signal detected by the AE sensor, and the axial vibration phase, which corresponds to the high spot position of the rotating part specified on the basis of the change over time in the axial vibration signal detected by the axial vibration sensor, and, on the basis of the phase difference between these, identifies the circumferential-direction position of where rubbing has occurred in the rotating machine.

First claim

The invention claimed is:

1 . A rubbing position identification device for a rotating machine that includes a fixed part and a rotating part, the device comprising:
at least one AE sensor for detecting an AE signal of the rotating machine; at least one shaft vibration sensor for detecting a shaft vibration signal of the rotating part; and a rubbing position identification unit for identifying a position of a rubbing occurrence location of the rotating machine in a circumferential direction based on a difference between an AE phase corresponding to a peak of an envelope specified based on a temporal change of the AE signal and a shaft vibration phase corresponding to a high spot position of the rotating part specified based on a temporal change of the shaft vibration signal in a case where rubbing occurs in the rotating machine.

2 . The rubbing position identification device for a rotating machine according to claim 1 , wherein, when the position in the circumferential direction is φrub, an attachment position of the shaft vibration sensor with respect to a reference position is φvib, the AE phase is θrub, and the shaft vibration phase is θvib, the position in the circumferential direction φrub is expressed by the following expression:
φrub=φvib+(θrub−θvib).

3 . The rubbing position identification device for a rotating machine according to claim 1 ,
wherein the at least one shaft vibration sensor is configured to detect the shaft vibration signal having an amplitude corresponding to a size of a clearance present between the shaft vibration sensor and the rotating part installed at the fixed part, and the rubbing position identification unit specifies the high spot position based on a maximum peak included in a temporal change of the amplitude.

4 . The rubbing position identification device for a rotating machine according to claim 1 ,
wherein the at least one shaft vibration sensor includes a first shaft vibration sensor and a second shaft vibration sensor having attachment angles different from each other, and the rubbing position identification unit obtains an orbit of the high spot position based on the shaft vibration signals detected by the first shaft vibration sensor and the second shaft vibration sensor, and identifies the position in the circumferential direction based on the orbit and the AE phase.

5 . The rubbing position identification device for a rotating machine according to claim 4 , wherein the rubbing position identification unit identifies the position in the circumferential direction via a normal direction of a tangent line passing through a point corresponding to the AE phase and plotted on the orbit.

6 . The rubbing position identification device for a rotating machine according to claim 1 ,
wherein the at least one shaft vibration sensor includes a third shaft vibration sensor and a fourth shaft vibration sensor installed at positions different from each other in an axial direction, and the rubbing position identification unit calculates the position in the axial direction via linear interpolation of shaft vibration vectors based on the shaft vibration signals detected by the third shaft vibration sensor and the fourth shaft vibration sensor.

7 . The rubbing position identification device for a rotating machine according to claim 1 ,
wherein the at least one shaft vibration sensor includes a fifth shaft vibration sensor and a sixth shaft vibration sensor installed at positions different from each other in an axial direction, and the rubbing position identification unit identifies the position in the circumferential direction by obtaining a shaft vibration vector corresponding to the rubbing occurrence location as a linear sum of shaft vibration vectors corresponding to the fifth shaft vibration sensor and the sixth shaft vibration sensor, by using a coefficient that defines a vibration amplitude ratio between the fifth shaft vibration sensor, the sixth shaft vibration sensor, and the rubbing occurrence location for each vibration mode obtained in a mode analysis.

8 . The rubbing position identification device for a rotating machine according to claim 1 , wherein the shaft vibration sensor and the AE sensor are provided in bearing boxes in which bearings that rotatably support the rotating part with respect to a stationary part are housed.

9 . The rubbing position identification device for a rotating machine according to claim 1 , wherein the rotating machine is a steam turbine.

10 . A rubbing position identification method for a rotating machine that includes a fixed part and a rotating part, the method comprising:
a step of detecting an AE signal of the rotating machine; a step of detecting a shaft vibration signal of the rotating part; and a step of identifying a position of a rubbing occurrence location of the rotating machine in a circumferential direction based on a difference between an AE phase corresponding to a peak of an envelope specified based on a temporal change of the AE signal and a shaft vibration phase corresponding to a high spot position of the rotating part specified based on a temporal change of the shaft vibration signal in a case where rubbing occurs in the rotating machine.

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Takeda Hiroki
• Kumagai Satoshi
• Kawabata Ryo
• Ishizawa Shuichi
• Yamashita Masahiko
• Tanaka Yoshinori

Classifications

• F05D2270/80

  Devices generating input signals, e.g. transducers, sensors, cameras or strain gauges · CPC title

• F05D2260/80

  Diagnostics · CPC title

• F05D2220/31

  in steam turbines · CPC title

• F05D2200/12

  Subtraction · CPC title

• F05D2200/11

  Sum · CPC title