Scheduling is crucial in maintaining the production of a plant or factory that runs at all hours. The goal is to prepare for everything, including regular maintenance, but operations are not always that predictable or simple. Whether or not you schedule downtime can sometimes depend more on the constraints of what you are producing than how you may want to operate.
There are two main operation modes that facilities are constrained by: either running to failure or running until a scheduled break occurs. Running to failure simply means operations do not stop unless something breaks or is failing. The failure transitions to downtime; time is then taken to make as many repairs as possible until things are running again. This works only because what is being produced is not time critical, and there is enough capacity to meet customer’s needs during this unscheduled downtime.
The other way of operating is by scheduling downtime. For operations that rely on every minute, that have a product that is time critical or has a brief shelf life and is likely very expensive: This is the means by which they run. Time itself is a constraint, and any lost production time results in resources that will never be recovered. Without scheduling for factory maintenance, both predictive and preventive, an operation risks not getting the product to the client.
For example: Quarries run to failure. Processes like this are easier to run without stopping, and failure isn’t a real concern. If a quarry stops crushing rock, it doesn’t hurt that product to sit on the line, and it can be stockpiled. Therefore, machinery, such as belts, is not going to be changed until it breaks. But when one piece of equipment does break, an opportunity arises to fix everything possible.
A pharmaceutical company, however, cannot take the chance of running to failure. Their product is very time sensitive, and customer needs are immediate. If it is left in the system before it can get packaged, product could be ruined, and the company could lose millions of dollars. It is more beneficial to keep the maintenance program up to date, to avoid the risk of unscheduled downtime. With the industry relying more on next-day delivery and in-time servicing, more companies are transitioning to predictive maintenance schedules. Production goes down only when it is supposed to, and the expected work is completed.
Even though many industries do run to failure, and it may work in how their business functions it’s really not the best option. Plant or factory maintenance depends on the type of operation, and it has to be tailored to your process, your system and your functions however it’s best to schedule repairs and maintenance whenever possible to ensure you have the staff and supplies on hand to do all the work that is needed. Keep in mind even the best of plans cannot account for everything, and it is important that you have a way to make repairs quickly.