Does it cost more maintenance or downtime? Is the money spent on industrial machinery maintenance before failure a cost or an investment?
Maintaining a piece of productive machinery means carrying out all the operations necessary to maintain an economically convenient functionality on it: a balance between the cost of maintenance operations and the effectiveness of the intervention.
The ever-increasing speed of innovations (also financed by incentives), has placed a magnifying glass on item maintenance, which today occupies an increasingly crucial role in the industry of all sizes and sectors. Perpetually confronted (and in antagonism) with replacement, it is an intervention strategy that solves the need to have the machinery always at maximum productivity.
Types of industrial machinery maintenance
For those who are no longer so young like me, the first idea that comes to mind when it comes to maintenance is the corrective one, that is, to intervene when there is a breakdown or – more generally – any problem that does not make the machinery work well.
But just like innovations, the types of maintenance are also constantly evolving. A first subdivision can be made taking into account time and predictability, which divides them into:
– Ordinary (scheduled) maintenance
– Extraordinary maintenance (unpredictable or unforeseen)
Other types instead are:
– Preventive
– Predictive
– Proactive
– Autonomous
– Improvements
Maintenance can include many interventions: from inspections and measurements to repairs and replacement of components, up to adjustment, set up, and testing before being able to restart, thus defining the activity concluded.
Usually, the path is this:
Fault Detection → Monitoring → Inspection → Cleaning → Repair → Replacement → Lubrication → Adjustment → Tuning → Testing → Measurement
The problems of machine downtime and lack of materials
As you can see, even without going into too much detail, maintenance isn’t just about fixing something that broke, with all due respect to all. The main problem involving maintenance is machine downtime, even if we deal with portable machines like this Dewalt D55146 Oil Free Portable Air Compressor.
Production is now more and more based on just-in-time, both as a process optimization (reduction of economic commitments, warehouse management, etc.) and because of the ever-faster change of components. This forces us to no longer have warehouses. Or rather, to have reduced the number of components to a minimum, which allows a safety margin to manage any problems.
As we have seen in this last period, the global variation in the availability of raw materials has an impact from an economic point of view: but this is not the only problem. The lack of material – combined with the lack of warehouses – results in the interruption of complete assembly lines, due to the lack of even some components.
And interrupting an assembly line in a JIT process and in increasingly optimized production processes, which use extreme waste reduction techniques – such as the LEAN method – means stopping other assembly lines downstream not only in the immediate vicinity, but also in other parts of the world.
Machinery maintenance: prevention is always better than cure
Let’s go back to maintenance: you cannot afford to wait for something to break to intervene, because the ever-shorter intervention times and the speed with which the various components and materials pass through the system, practically obliges you to foresee what could break. Obviously, for the forecast, it is necessary to study the process and components in advance, estimating reliability and hours of operation without probable breakages or malfunctions.
Not only that, but it is also necessary to constantly monitor – sometimes in real time – some operating parameters or unwanted effects. These measurements can be made directly (such as the vibration analysis) or indirectly (such as the analysis of cooling fluids, which monitors the change in the chemical and physical characteristics of the fluids present in the circuits).
This must be done right from the start and, therefore, already in the design phase! The choice to simplify processes and mechanisms as much as possible – and minimize the number of components – optimizes operation. On the other hand, already predicting what the critical points could be, analyzing with simulations and calculations the operation, kinematics, stresses, and wear – even in extreme conditions – also allows you to design what the checks will be, their frequency, the warning signs and how to interpret them.
Any information can be data, even non-numerical information. When there is a difference between the estimated and the actual calculation, all this can help you understand the reasons and correct the anomalies. On the basis of this information, you can finally proceed with the drafting of maintenance plans – using the various types seen above – individually or in combination.
