What does it mean to 'design-out' maintenance?
Sometimes, comments on LinkedIn posts really make me think. For example...
"Don't forget to design out maintenance rather than just designing for maintenance"
I read that comment (or words to that effect) on a post a few weeks ago (I regret not saving it to refer to here. It did happen though, I promise. I think the post was talking about the GCAP aeroplane programme) and it led me to wonder…"what does designing out maintenance actually mean?".
??? Maintenance is the act of preserving a condition or situation
Maintenance is an annoyance. There's no denying it.
No organisation that buys equipment, wants to do maintenance. If there was a no maintenance option, that's the one that they'd buy.
Ultimately, we have to do maintenance because being used for its purpose takes its toll on equipment. When we do maintenance, we're fighting the impact of operations on our equipment to ensure that our equipment is still capable of performing those operations.
Is it really possible to design maintenance out? Probably not. Maintenance is inevitable.
We can reduce the maintenance burden.
If we need to do maintenance because of the impact of operations on equipment, that immediately presents two options for designing out maintenance…
?????????????? 1. Reduce the strain that operations places on equipment
?????????????? 2. Use equipment that is more resistant to the strain of operations
Integrated support recognises that the way equipment is used, the equipment itself and the maintenance of the equipment forms part of a system.
Taking that systems approach allows us to trade-off between elements of the system. For maintenance, that means that we can strike a balance between the cost of investing in equipment which is resistant to the effects of operations and the cost of performing maintenance where the equipment is susceptible to the strain of operations.
That doesn't really design maintenance out though. It might reduce it, by striking the balance, but it doesn't necessarily design it out.
Techniques like reliability-centered maintenance (RCM) analysis look to reduce the maintenance burden by intervening only when necessary.
On condition maintenance (or condition-based maintenance (CBM) if you prefer that title), for example, focusses on tracking the progression of a failure mode so that a maintenance planner can predict when the failure mode is likely to result in functional failure so that they can plan their intervention before that happens.
There's three parts to on condition maintenance…
??Measure
??Predict
???Intervene
Traditional condition monitoring techniques might use the maintainer to take the measurements required to inform the predictions. These techniques can be quite intrusive, and time consuming, depending on how accessible the item is for measurement and the technique used to measure it.
Maintenance 4.0 can apply modern technologies like internet of things, artificial intelligence, machine learning, big data, etc. to track the prediction of failures.
So, designing a new piece of equipment, with the myriad sensors required to track the progression of failure modes, supported by a maintenance management system that can interpret the data, make predictions and schedule intervention without the need for human interaction - that might be what we mean by designing out maintenance.
Except, it isn't really doing that. Maintenance still requires humans to perform the intervention.
What we'd really be doing is designing out the maintainer from condition monitoring and prediction.
??Measure (this is isn't maintenance, you can't preserve a condition by measuring it)
??Predict (this isn't maintenance, you can't preserve a condition by just guessing when it will become a problem)
???Intervene (this is maintenance, the act of preserving a condition before it becomes a problem)
Maybe that's the right answer.
More likely, it's a combination…
And then, where required...
But, let's also not lose sight of the fact that the inclusion of condition monitoring systems will also impose a maintenance burden.
Perhaps a better imperative would be "don't forget that maintenance is an investment that is forced upon equipment owners. Think carefully about the balance between your equipment design and its maintenance requirements. It's a balance."
(Incidentally, if being used for its purpose is the No.1 cause of damage to our equipment. A close second is not being used at all, machines don't like that. Third is probably being used for a purpose other than what is was designed for.)
Will there ever be a truly 'maintenance-free' complex piece of equipment?
System Safety Engineering and Management of Complex Systems; Risk Management Advisor...Complex System Risks
3 天前CONSIDER MAINTAINABILITY ENGINEERING IN CONCERT WITH SYSTEM ASSURANCE… As you know, there are many aspects that come into play when one addresses inclusive system assurance associated with maintainability engineering: ·??????Integrated system requirements associated with system safety, human factors, reliability, logistics, security, availability, software assurances, quality, and survivability. ·??????Design the system applying minimal maintenance attributes: screening, safety margin, safety factor. ·??????Design the system to proactively monitor, detect, isolate, and automatically self-correct. ·??????Understand limitations of stochastic processes and models. ·??????Exceed expected design life. ·??????Consider accident and system life cycle stressors. ·??????Evaluate system dynamics and change. ·??????Apply reliability engineering aspects towards robust design methods: testing, screening, reliability growth. ·??????Address human engineering interface requirements. ·??????Allocate functionality in support of minimal maintenance: the human, hardware, firmware, software, operational logic.