Aircraft maintenance is often used as an example of a good operating method in predictive maintenance. High safety targets and the maximization of dispatch reliability have led to a good, systematic method of developing predictive maintenance programs. Thanks to modern technology, industrial maintenance can now also jump directly to the forefront of development.
In the early years of aviation, aircraft maintenance was primarily developed by pilots and mechanics whose work was mainly based on their own experiences. With the introduction of commercial aviation and large airliners to the market, safety and reliability requirements also increased, resulting in a need to develop maintenance programs. Fixed maintenance intervals (HT – hard time maintenance) were established for structures and equipment to restore the object of maintenance to its original condition through maintenance measures. The primary purpose of this was to maximize safety.
In the 1960s, maintenance systems began evolving in such a way that instead of a complete overhaul, mechanics would attempt to locate faulty components through testing before they malfunctioned. The purpose of this was to minimize operational failures (OC – on-condition maintenance). This also helped to eliminate the problem that a sensible fixed-period maintenance measure could not necessarily be developed for all objects of maintenance.
In the 1970s, the introduction of next-generation aircraft to the market brought with it a need to develop a third separate maintenance process, condition monitoring (CM). Instead of conducting tests, this process monitors the condition of the system (by measuring vibration or oil consumption, for example) and compares it to established, permissible limits.
The aircraft currently on the market produce measurement data via hundreds or even thousands of sensors every second. The next big step in the evolution of aircraft maintenance programs will be taken by utilizing this data.
The fourth and next maintenance process will be predictive maintenance (PM). It will significantly improve operational reliability and predictability as well as the timely availability of the resources required by maintenance operations. In aviation, safety always comes first, which is why all related operations are heavily regulated and subject to authorization. This regulation is the reason why it will take several more years before this change can be put into practice.
Safety is also of paramount importance in industrial maintenance. In many respects, the production equipment and systems currently used by industries correspond to the complex systems in aircraft with regard to automation. The equipment hierarchies of production facilities are often maintained and their reliability is monitored with the same accuracy as in aircraft. However, the regulation of industrial maintenance does not limit the rate of operational development to the extent it does in aviation. We already possess the information, expertise and technology required to start predictive maintenance.
What would you say if I told you that 80% of the technical failures at your production facility could be predicted early enough to prevent the failure from occurring, thus preventing production losses? What if erroneous diagnoses also amounted to less than 1%? Would this generate productivity gains in your company, and if so, how much? Does this sound too good to be true?
But it is true and already possible now. However, the concretization of benefits comprises more than just conveying data to the "industrial internet", finding the right algorithm or purchasing the right software. The right and reliable information must be producible in a comprehensible form, in a timely manner and conveyed to the right person, who must take the right actions. This is also a very large process of change for the company, and the concretization of benefits requires changes in the daily duties of real people. This is not something that can be done by information systems alone. All of this is part of our core expertise. If your company is ready to move to a completely new level in maintenance, we would be happy to tell you more about our solutions.
The author is a business unit director who is in charge of Maintpartner's IN concept.
Manu Skyttä, +358 (0)400 999 822 manu.skytta(at)maintpartner.com