Condition Monitoring is nothing new.
Ever since the early days of the Industrial Revolution, when people first started relying on machinery, it was discovered the painful way that failures can occur – and sometimes with dramatic and catastrophic consequences.
Boilers exploded, train wheels fractured, bridges collapsed, brakes failed. Each tragedy prompted the search for a means of avoiding repetition – and it was realised that faults very rarely happen out of nowhere, rather, defects develop over a period of time, gradually deteriorating until they reach the point of failure. If these defects can be detected before they reach the critical point, then catastrophic failure can be avoided.
The railways were a good example. “Wheel Tappers” went around stationary rolling stock with a long handled hammer, monitoring the wheels’ condition by tapping each wheel and listening for whether it rang out like a bell, or gave a dull, cracked sound – indicating literally a crack. These guys became the world’s first condition monitoring engineers.
I cracks were detected, the wheels would be replaced at the next opportunity – ie wheel replacement was done on a Condition Based Maintenance regime.
Track was as much an area of possible failure as the wheels that ran on it, so was also inspected very regularly. The railways continued with human observation of faults for well over a century – until recent decades, and even in some places to this day, it was mandatory for a permanent way inspector to walk along the track and inspect it to check for any developing defects. More recently, the manual process has been replaced by train mounted camera and ultrasound checks – so even this most traditional industry has now adopted modern, condition monitoring technologies.
Steam engines were also a good example of condition based maintenance – the locomotive engineers, working very close up to the machinery, would be well aware of any early stages of defect development, such as steam leaks out of piston rod seals, valve stems, or gauges, and would instigate maintenance work as required – routinely nipping up glands whenever required. So their machines were maintained on the basis of condition: if it showed signs of leakage, adjust it slightly to correct it.
So the history of condition monitoring and condition based maintenance is very well established, together with the principle that automated, instrumented measurement techniques give a more reliable method than relying on subjective human senses.