Method and system for monitoring bearings

• US 20030066352A1
• Filed: 10/05/2001
• Published: 04/10/2003
• Est. Priority Date: 10/05/2001
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Simpson, William Joseph, Watson, Thomas Ulmont, Myers, William Joseph Jr., Leamy, Kevin Richard
• Granted Patent: US 6,711,952 B2
• Time in Patent Office: Days
• US Class Current: 73/593
• CPC Class Codes: F01D 21/00 Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for
• CPC Class Codes: F01D 25/04 Antivibration arrangements
• CPC Class Codes: F05D 2240/50 Bearings
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F05D 2270/09 to cope with emergencies
• CPC Class Codes: F16C 19/527 related to vibration and noise
• CPC Class Codes: F16C 19/55 with intermediate floating or independently-driven rings rotating at reduced speed or with other differential ball or roller bearings
• CPC Class Codes: F16C 2233/00 Monitoring condition, e.g. temperature, load, vibration
• CPC Class Codes: F16C 2360/23 Gas turbine engines
• CPC Class Codes: G01H 1/003 of rotating machines G01H1/10 takes precedence
• CPC Class Codes: G01H 1/08 Amplitude
• CPC Class Codes: G01M 13/045 Acoustic or vibration analysis
• CPC Class Codes: G01N 2291/2696 Wheels, Gears, Bearings
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A method and system for monitoring the condition of a bearing mounted on a rotating shaft, particularly one present in an aircraft gas turbine engine, where the vibration sensor that monitors the bearing is remote therefrom but proximate to the rotating shaft. The vibration sensor obtains a broadband signal having frequencies that include the bearing defect peak of the monitored bearing. The broadband signal is analyzed to identify the presence of the bearing defect peak. If the bearing defect peak is present, the amplitude of this peak is quantified to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.

Claims

1. A method for monitoring the condition of a bearing mounted on a rotating shaft wherein a vibration sensor that monitors the bearing is remote therefrom but proximate to the rotating shaft, the method comprising the steps of:

a. obtaining through the vibration sensor a broadband signal having frequencies that include the bearing defect peak of the monitored bearing;

b. analyzing the broadband signal to identify the presence of the bearing defect peak; and

c. if the bearing defect peak is present, quantifying the amplitude of the bearing defect peak to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.

2. The method of claim 1 wherein the rotating shaft is present in an aircraft gas turbine engine.

3. The method of claim 2 wherein multiple bearings are mounted on the rotating shaft.

4. The method of claim 2 wherein the engine comprises a higher temperature section and lower temperature section, and wherein the bearing being monitored is located in the higher temperature section and the vibration sensor is located in the lower temperature section.

5. The method claim 2 wherein the bearing being monitored is a differential roller bearing having an inner rotating race and an outer rotating race and wherein the rotational speed of the inner race and the rotational speed of the outer race are obtained and included in the analysis of the broadband signal in step (b).

6. The method of claim 5 wherein the rotational speeds of the inner and outer races are obtained during transient engine speed conditions.

7. The method of claim 5 wherein the rotational speeds of the inner and outer races are obtained during steady state engine speed conditions.

8. The method of claim 2 which comprises the further step (d) of issuing a message as to the appropriate action to be taken if it is determined during step (c) that the threshold criteria has at least been reached.

9. The method of claim 2 wherein step (c) comprises obtaining a plot of the amplitude values of the bearing defect peak to progressively monitor the degradation of the bearing.

10. A system for monitoring the condition of a bearing mounted on a rotating shaft, the system comprising:

(a) a vibration sensor remote from the monitored bearing but proximate to the rotating shaft, the vibration sensor being capable of obtaining a broadband signal having frequencies that include a bearing defect peak of the monitored bearing; and

(b) a vibration monitor that is capable of;

(1) collecting the broadband signal from the vibration sensor;

(2) analyzing the broadband signal to identify the presence of the bearing defect peak; and

(3) if the bearing defect peak is present, quantifying the amplitude of the bearing defect peak to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.

11. The system of claim 10 wherein the rotating shaft is present in an aircraft gas turbine engine.

12. The system of claim 11 wherein multiple bearings are mounted on the rotating shaft.

13. The system claim 12 wherein the engine comprises a higher temperature section and lower temperature section, and wherein the bearing being monitored is located in the higher temperature section and the vibration sensor is located in the lower temperature section.

14. The system of claim 13 wherein the bearing being monitored is a differential roller bearing having an inner rotating race and an outer rotating race and wherein the system further comprises a first speed sensor and a second speed sensor, the first speed sensor obtaining a signal on the rotational speed of the inner race and the second speed sensor obtaining a signal on the rotational speed of the outer race, and wherein the vibration monitor collects and includes the signals obtained by the first and second speed sensors in the analysis of the broadband signal in step (b).

15. The system of claim 14 wherein the vibration monitor is capable of issuing a message as to the appropriate action to be taken if it is determined during step (c) that the threshold criteria has at least been reached.

16. Software for use in a computerized system for monitoring the condition of a bearing mounted on a rotating shaft, the system including a vibration sensor remote from the monitored bearing but proximate to the rotating shaft, the vibration sensor being capable of obtaining a broadband signal having frequencies that include a bearing defect peak of the monitored bearing and a vibration monitor capable of installing and utilizing the software;

the software being capable, when installed on the vibration monitor, of;

(a) collecting the broadband signal from the vibration sensor;

(b) analyzing the broadband signal to identify the presence of the bearing defect peak; and

(c) if the bearing defect peak is present, quantifying the amplitude of the bearing defect peak to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.

17. The software of claim 16 that is stored and installable from one or more nonvolatile electronic storage media.

18. The software of claim 17 wherein the electronic media are floppy disks or CD ROM disks.

19. The software of claim 18 which has instructions provided or associated therewith for how to use the software with the system, how to install the software on the system, or how to use with and install the software on the system.

20. The software of claim 16 wherein the rotating shaft is present in an aircraft gas turbine engine.

21. The software of claim 20 wherein the bearing being monitored is a differential roller bearing having an inner rotating race and an outer rotating race and wherein the system further comprises a first speed sensor and a second speed sensor, the first speed sensor obtaining a signal on the rotational speed of the inner race and the second speed sensor obtaining a signal on the rotational speed of the outer race, and wherein the software is capable of allowing the vibration monitor to collect and include the signals obtained by the first and second speed sensors in the analysis of the broadband signal in step (b).

22. The software of claim 21 which is capable of allowing the vibration monitor to issue a message as to the appropriate action to be taken if it is determined during step (c) that the threshold criteria has at least been reached.