Preventive maintenance of equipment has a long history as a standard practice, but upon closer examination, it can be seen as inefficient. Today, the preferred method is transitioning from routine preventive maintenance of equipment to a more advanced approach called prescriptive, predictive maintenance. This article illustrates the potential of a vast opportunity to indulge in new skill sets, refine processes and redefine practices to create autonomy in Maintenance, Repair and Overhaul (MRO) by exploiting the power of technology and innovation.
First, an untold story – Micheal Shumacker is among the greatest names in Formula 1 Car Racing. Not entirely satisfied with the Ferrari gadgets to claim his rightful place under the sun, a brainstorming ensued with the best of brains in Italy, France and Germany on torsion and vibration to look beyond the apparent power, torque, RPM relationship of the engine and the speedometer of the car. This analysis led to humanising the car by picking angular torques of shafts read through the teeth of the flywheel. It redefined the dashboard with angular velocity and angular acceleration depictions. The legend goes it developed a Hey Google intuitive relationship with his Ferrari, to read the treacherous Formula 1 circuit and be on top in every race.
It was in the dawn of Y2k! A technology and innovation marvel took birth, and it was the first Asset (FERRARI) Humanised! The wheels of technology turned at an unprecedented pace, and yesterday, I asked my Google Play station, “Hey Google, what will be the weather in Boston tomorrow?” As if a soothsayer, it quipped, “Rain, thundershower throughout the day with snowfall in the night”, and it happened—yet another apt example of an Asset Humanised building transparency through traceability leading to technological transformation.
Wear and tear of any asset is inevitable, but when it happens at a time when one least expects, it creates a fear of the unknown. This fear or uncertainty results in the creation of maintenance practices with the thought process of being relatively safe than sorry. But despite regular preventive and periodic maintenance, unannounced failures and catastrophes are a reality – Morbi bridge failure, breakdown of tanks and other critical equipment on the battlefield, breakdown of plant and machinery on industrial floors, sudden breakdown of the VIP fleet despite best maintenance practices, to name a few.
The reason is simple – a system comprises subsystems and components which enmesh and operate the system. The breakdown happens at the weakest link, and once replaced, the following weak link may manifest, awaiting the subsequent breakdown and the failure sympathetically detonating from weakness to weakness.
Critique on Periodic Preventive Maintenance
Total Quality Management (TQM), in the parlance of equipment management, requires that the right equipment is at the right place, time, and condition. With this intent, periodic and preventive maintenance schedules were defined to retain high equipment reliability. Data analytics based on OEM reliability data and repair activity data were analysed to develop Specific, Measurable, Achievable, Realistic and Time-bound (SMART) intervention programs. It has stood the test of time and reduces risk but is resource intensive, inventory intensive, may not consider optimum exploitation of the affected assemblies or components, and time and cost prohibit. The equipment is a mute piece and hence could be subjected to any intervention based on the operator or maintainer.
A policy directive reads – this tank will undergo a medium reset after 12 years (vintage) or 4500 km (exploitation) and an overhaul at 21 years or 10,000 km, whichever is earlier. The user is conscious, and the equipment is mute, so the maintenance echelon carries out the life-enhancement intervention.
Now, envision an excerpt in a human medical intervention program – a human would undergo a heart bypass at 35 years (vintage) and an open heart surgery at 50 years (vintage). But that’s bizarre – so say all of us. There is a good reason – humans can express, so medical interventions are condition-based and symptomatic.
The equipment is mute and, hence, undergoes over maintenance based on policies which can be questioned – why should equipment which has turned 15 years with 2000 km be given the same treatment as the one with 10 years with 5000 km? But what if the equipment had all five senses like humans and more – would it allow periodic preventive maintenance interventions if they were unwarranted? Maybe NO.
The new technology paradigm is defined by 4Ds – Data, Digitization, Digitalization and Disruption. These have propelled a tenacious spiral of digital transformation, which in the continuum of time has revolutionised the nature and character of business, if not disrupted the business models and business practices life cycles. In the disrupted world, data is the new oil and technology is the new oil refinery to configure an info system capable of humanising assets. Condition-based reliability-centric monitoring of assets is the need of the hour. The good news is that 4Ds guarantee the aforesaid machine-to-machine (M2M) and human-machine interface (HMI).
Humanising assets is a simple concept. The human body is a complex system of systems with five basic sensory organs, but a sensor-based anatomy of systems (respiratory, circulatory, endocrinology…..) duly networked by the nervous systems, all commanded and controlled by the cerebral system. The system is well monitored, and the why, when, which, what, and where for maintenance and any intervention is indicated by well-defined symptom-based diagnostics. No individual allows uncalled-for medical intervention. The key words, therefore, in asset life cycle sustenance support are reliability-centric, precise predictive and prescriptive maintenance based on data analysed from technology driven M2M and HMI.
That said, given the technology thresholds of the 21st Century, there is a need to Humanise Assets by building an information system of sensors and IoT devices for adequate condition-based monitoring and maintenance. Taking a leaf from the Shumaker experiment, one of the panaceas for power packs and engines is a torsional vibration sensor. A pilot project using a torsion vibration sensor was carried out on armoured fighting vehicles. The results were highly encouraging. The sensor unobtrusively deployed with the flywheel gave the status of engine bearings, shafts, pistons, gaskets and precise condition on a dashboard indicating green (all is well), amber (engine cylinder head gasket needs a change) and red (the engine bearings may fail anytime) giving the user and maintenance agencies a condition based yell.
These shifts focus from case high-cost periodic and preventive maintenance to visibility-driven just-in-time prescriptive maintenance. A good start would be high population operationally mission-critical legacy assets – tanks, guns, radars, battle taxis, load carriers and generators, to name a few big tickets! Defining the predictive prescriptive maintenance assessment, a sensor network design can be developed and deployed. It will instil higher mission reliability and readiness, more profound user confidence, prune high-cost just-in-case inventories, and augment operational effectiveness.
The emerging technologies landscape is driven by technology, data, semiconductors and software, leading to automation, autonomy, precision and positioning systems. The technology stacks to create machine-to-machine and human-machine interface comprise LIDAR, IoT and sensors, 5G, big data analytics, DCS/SCADA, 3 D printing, AR, VR, and AI, to name a few; there is a vast opportunity to indulge in new skill sets, refine processes and redefine practices to create autonomy in Maintenance, Repair and Overhaul (MRO) by exploiting the power of technology and innovation.
The sensors and IoT provide a predictive and prescriptive reliability-centric just-in-time maintenance paradigm wherein the interventions can be precise and executed when situation, time and space permit – in war and peace, battlefield and industry alike. This transformation of periodic preventive maintenance to prescriptive, predictive maintenance (PM2PM) is the trend of future MRO and the idea – for which time has arrived. Opportunity beckons!
Lt Gen (Dr) Anil Kapoor (Retd)