System and methodology for vibration analysis and conditon monitoring

• US 20070032966A1
• Filed: 09/26/2006
• Published: 02/08/2007
• Est. Priority Date: 06/07/2002
• Status: Abandoned Application

• Current Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Inventors: Song, Limin
• Application Number:
  US11/526,597
• Publication Number:
  US 20070032966A1
• Time in Patent Office: Days
• US Class Current: 702/35
• CPC Class Codes: G05B 23/0221 Preprocessing measurements, e.g. data collection rate adjustment; Standardization of measurements; Time series or signal analysis, e.g. frequency analysis or wavelets; Trustworthiness of measurements; Indexes therefor; Measurements using easily measured parameters to estimate parameters difficult to measure; Virtual sensor creation; De-noising; Sensor fusion; Unconventional preprocessing inherently present in specific fault detection methods like PCA-based methods
• CPC Class Codes: G05B 23/0243 model based detection method, e.g. first-principles knowledge model

Abstract

A system and methodology for continuous condition monitoring of rotating equipment employ adaptive signal processing techniques to determine the RPM of a rotating machine from the time-based vibration data. RPM is determined based upon the input of a digitized time-based sample sequence of vibration data acquired directly from a vibration transducer for on-line real-time measurement of the machine RPM. Once RPM is determined, online vibration analysis for a given RPM or set of RPMs may be performed. The present invention extracts characteristic vibration features from vibration data and uses these extracted values to provide condition detection and diagnoses of machine faults.

Claims

1. A method for monitoring machine faults comprising:

determining one or more base vibration features associated with said machine;

acquiring time-based vibration data samples from a vibration transducer in physical contact with said machine;

determining a machine operating speed estimate for said machine based upon the time-based vibration data samples from the vibration transducer using a continuous vibration model;

acquiring vibration data for said machine occurring at said machine operating speed; and

determining whether one or more faults exists within said machine based upon a comparison of said base vibration features with said vibration data occurring at said machine operating speed.

2. The method of claim 1 wherein said determining whether one or more faults exists is reported to an operator on a periodic basis.

3. The method of claim 1 wherein said machine operating speed is reported to an operator on a periodic basis.

4. The method of claim 1 wherein said base vibration features comprise vibration features at a plurality of machine operating speeds.

5. The method of claim 4 wherein said determining whether one or more faults exists comprises a comparison of base vibration features against vibration data at a plurality of machine operating speeds.

6. The method of claim 1 wherein said determining one or more base features associated with a machine further comprises determining symptom frequencies and symptom levels associated with said machine.

7. A method for monitoring machine faults of a machine comprising:

acquiring time-based vibration data samples associated with said machine using a vibration transducer;

using said time-based vibration data samples from the vibration transducer to extract a current RPM value for said machine;

extracting vibration features corresponding to said extracted RPM value for said machine; and

measuring the degree of machine fault symptoms based upon said extracted vibration features and said time-based vibration data samples.

8. The method of claim 7 further comprising:

performing condition diagnosis for said machine based upon said degree of machine fault symptoms.

9. The method of claim 7 wherein said vibration data is measured at ordered multiples of machine RPM.

10. The method of claim 7 wherein said vibration data is measured at non-ordered multiples of machine RPM.

11. The method of claim 7 wherein said monitored machine fault is a shaft imbalance.

12. The method of claim 7 wherein said monitored machine fault is a bearing problem.

13. A system for detecting faults within a machine comprising:

means for determining one or more base vibration features associated with said machine;

means for acquiring time-based vibration data samples from a vibration transducer in physical contact with said machine, wherein the means for acquiring time-based vibration data samples including a vibration transducer;

means for determining a machine operating speed estimate for said machine based upon the time-based vibration data samples from the vibration transducer using a continuous vibration model;

means for acquiring vibration data for said machine occurring at said machine operating speed; and

means for determining whether one or more faults exists within said machine based upon a comparison of said base vibration features with said vibration data occurring at said machine operating speed.

14. The system of claim 13 wherein said detected faults are reported to an operator on a periodic basis.

15. The system according to claim 13,

wherein said machine speed is reported to an operator on a periodic basis.

16. The system according to claim 13, wherein said base vibration feature comprise vibration features at a plurality of machine speeds.

17. The system according to claim 13, wherein said machine is shut down in the presence of one or more detected faults.