CBM is Effective but may be Inefficient
A study of oil-based CBM program of gearboxes of locomotives used by Canadian Pacific Railway (Aghjagan 1989) indicated that since CBM was commissioned, which entailed 3 to 4 oil samples per week per locomotive for 52 weeks a year, the incidences of failures of gearboxes while in use fell by 90%. This is a significant achievement. However, when the gearboxes that were indicated for maintenance by the monitoring system, were subsequently stripped down for reconditioning/overhaul, there was nothing evidently wrong in 50% of the case.
Clearly, CBM can be highly effective but may also be inefficient at the same time.
Hence, modeling is necessary to improve the cost-effectiveness and efficiency of a CBM system.
Needless to say that it is a crying need for industries at this point in time when profit margins are under tighter squeeze.
Unfortunately, most CBM systems as practiced in the industries are not supported by a modeling system.
Source: Complex System Maintenance Handbook, Khairy A.H. Kobbacy, D. N. Prabhakar Murthy (Editors), 2008, Chapter 22, CBM Modeling by Wenbin Wang, page116, Section 5.3
Sr. Management, Plant Asset Management Leader
4 年CBM Diagnostics may not be effective, if parameters selection is inadequate. Best way could be to design a Reliability Health Index with combination of CBM parameters, On line/ Offline Inspections observations & performance parameters.Oil testing based on Quality/ Quantitative parameters may not yield desired results. It may need additional inputs like-Lubrication System & Selection adequacy, temp profile, leakage, Vibration, driven & driver interaction including Alignment, load. Gearbox might be ultimate failure but failure initiation could have other linkage.