The choice between predictive and preventative maintenance depends very much on the application, as Nikesh Mistry, Sector Head of Industrial Automation at GAMBICA, explains.
I’d like you to take a second to imagine that hypothetically, there are only two different methods that you can use to prevent yourself from getting wet in the rain. The choice is yours; either have a cover built over you, effective at all times, or have the ability to monitor the daily weather conditions and cover yourself accordingly and as and when required. Now, there may be an obvious answer, but perhaps consider which would be better suited given your current environment. For example, in an area where rain is recurrent, it might be more beneficial to have a permanent cover. Alternatively, suppose you work in a building with a low ceiling, always having a cover may jeopardise your mobility. So it would be more beneficial to monitor when a cover is required and act accordingly. In a nutshell, this is parallel to the difference between preventive and predictive maintenance.
With a push towards the fourth industrial revolution, machines being more connected and having the ability to utilise the copious amount of data we’re able to gather is essential. Both predictive and preventive maintenance are methods designed to improve the reliability of our equipment or reduce the level of action required to facilitate failure. You may ask, why exhaust resources on predicting what could potentially go wrong if I’m able to prevent it from the outset?
This is a common misconception, better understood when considering the rain example given above. From a manufacturer’s perspective, both methods incur a cost and require a certain level of training and resources. It is, therefore, crucial to ensure the right method is adopted, if not both.
Which is the right method? As above, before making this decision, each unique environment should be considered. Preventive maintenance is installing the ability to avert something from happening. This could be stopping a particular machine from timing out due to inactivity. To do this, preventive maintenance will consistently check for inactivity, at scheduled intervals, and if a moment of inactivity is detected, the action required to prevent the timeout would be performed. Now, it doesn’t require an in-depth understanding of downtime to notice that having a form of preventive maintenance is a much more efficient use of resource than applying reactive maintenance. However, consistent checking may incur costs.
Imagine, for example, a pie in the oven: continually opening and closing the door to check it is done would alter its ability to cook properly or perhaps wear the oven door down at a faster rate. In this case, it may be more advantageous to have a system built within the oven to be able to monitor the pie and inform you once it has cooked. This would be similar to that of a predictive maintenance system.
It would require a level of constant monitoring to be successful. For instance, the machine would need to adjust itself as the pie becomes progressively cooked, and in turn, give a signal before the pie burns. This is parallel to how predictive maintenance would help benefit machinery. If a machine could monitor the condition of a particular component as it begins to deteriorate, then maintenance can be performed as and when required, without wasting resource through constant inspection.
Both of these methodologies can be used in conjunction with each other; however, for maximum benefit, ensuring that the correct combination has been implemented is imperative. Each application should be considered on a use case basis. Most manufacturing equipment, old and new, gathers valuable data and modern technology allows us to utilise this data to minimise downtime, boost efficiency and capitalise on resources.
If you’re unsure as to how to evaluate which maintenance method is most suitable, get in touch with GAMBICA and unlock the ability to discuss and gain advice from numerous other industry experts.