Accession Number : ADA311546

Title :   A Comparison of Digital and Analogue Vibration Analysis Techniques for the Detection of Ball Bearing Faults.

Descriptive Note : Technical note,

Corporate Author : DEFENCE SCIENCE AND TECHNOLOGY ORGANIZATION CANBERRA (AUSTRALIA)

Personal Author(s) : Shilo, Mark

PDF Url : ADA311546

Report Date : JAN 1996

Pagination or Media Count : 30

Abstract : 'Envelope Detection' is a technique of using vibration analysis for detecting the presence of surface defect faults in ball bearings and rolling element bearings. Envelope detection has been demonstrated to be capable of detecting ball bearing faults where traditional vibration analysis techniques have been unsuccessful. There are many tools commercially available for bearing fault detection, some of which use the technique of envelope detection. Personal computers (PCs) are used extensively for all kinds of vibration analysis including envelope detection, and the question has arisen as to how the efficiency of the digital methods employed in computers compares with that of analogue methods used by commercial tools in detecting ball bearing faults. The Bruel and Kjaer analogue envelope detector WB1048 was chosen for a comparison with a PC-based digital envelope detection algorithm, and three test specimen bail bearings were used to gauge the performance of the two fault detection techniques. The brand-new, fault free test specimens were driven at high speed under high load while their vibration signatures were recorded, until surface defect faults developed naturally. Analysis of the vibration recordings with both digital and analogue envelope detection techniques showed that both methods were able to detect the onset of the naturally occurring fault at the same point in the vibration recordings, but the analogue device provided results more quickly than the digital technique, due to computation time needed for the digital technique. However, the digital technique offers other advantages that the analogue device cannot, such as readily linking with a database, and other PC-based condition monitoring and trending programs.

Descriptors :   *VIBRATION, *DETECTION, *COMPARISON, *ANALOG SYSTEMS, *DIGITAL COMPUTERS, *FAULTS, *DEFECT ANALYSIS, *BALL BEARINGS, DATA BASES, COMPUTATIONS, COMMERCE, LIFE EXPECTANCY(SERVICE LIFE), TOOLS, TIME, SURFACES, SIGNATURES, RECORDING SYSTEMS, ROLLER BEARINGS, MICROCOMPUTERS, AUSTRALIA.

Subject Categories : Computer Programming and Software
      Machinery and Tools

Distribution Statement : APPROVED FOR PUBLIC RELEASE