Condition based maintenance (CBM) i

Condition based maintenance (CBM) is a technique that relies on data and analysis to identify
and diagnose equipment faults through the use of sensors and other data collection devices.
CBM is used normally for high asset value equipment in sectors such as aviation and
automobile racing (Formula One). As a proactive maintenance technique, CBM is rarely used
in the general maintenance areas of the built environment. It is believed generally that CBM is
too expensive given the normal equipment asset values within the built environment.
Therefore, a fifteen-month monitoring study was undertaken manually to determine the
feasibility and impact of CBM on eighty-three rotary assets (valued at £1.5 mil. and about 5%
of the existing centrifugal pumps and air handling unit fans and motors) in a large public sector
building in the UK (over 1 mil. square meters of space) with a maintenance budget of circa £4
mil per annum. The benefits of moving to a CBM approach are expected to have positive
impacts on the reliability, downtime, replacement and operational costs, and life of an asset.
The results of the pilot study indicated that there were significant opportunities across the entire
spectrum of benefit categories. These included: improved fault detection and diagnosis;
including a 10% reduction in reactive maintenance and 11% labor cost savings; 5% estimated
reduction in electricity usage and associated carbon emissions, as well as extend asset life.
Further, based on this pilot a CBM framework was developed and funded to take a sensor based
analysis of these assets in anticipation of gaining a 239% net savings on total cost to implement
over the life of the PFI contract.