Analysis, approach and assessment of vibration criteria in shipboard machinery condition monitoring and diagnostics
By: by C.S. Liu, J.J. Jeon, and Y.S. Shin
Contributors: Jeon, Jae-Jin; Shin, Y. S.; Naval Postgraduate School (U.S.). Dept. of Mechanical Engineering
Publisher: Naval Postgraduate School; Available from National Technical Information Service
Published: 1993
Place of publication: Monterey, Calif; Springfield, Va
Language: eng
Number of pages: 198
Subjects: STATISTICAL DISTRIBUTIONS; MACHINES; SHIPBOARD; DIAGNOSTIC EQUIPMENT; COMPUTER  AIDED DIAGNOSIS; VIBRATION; TIME DOMAIN
Other titles: NPS-ME-93-005A.
Description: The setting of alarm levels plays a vital role in a machinery condition monitoring and      diagnostic system. In this research, two approaches to setting vibration alarm levels using      vibration signals produced by fire pumps are presented in the time and frequency      domains. In the time domain, the cross peak analysis is proposed to extract the dominate      peak points. The distribution of these cross peak points is found to have a lognormal      distribution and can be normalized to a Normal distribution in the VdB domain. The      computed g+2a value in the VdB domain is suggested for use as the alarm level. In the      frequency domain, 1/1 octave band analysis is introduced. Three artificial fault simulations      are conducted to compare the 1/1 octave band method with the broadband method. The      results show that the 1/1 octave band method is more sensitive to the changes in VdB      level than the broadband method. The computer programs to perform these two analyses      are written using MATLAB. Alarm Level, Vibration, Fire Pump, Cross Peak Analysis,      1/1 Octave Band Analysis, Condition Monitoring and Diagnostics.
Notes: Title from cover.

"NPS-ME-93-005A."

"September 30, 1993."

Includes bibliographical references (p. 194-195)

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