Scheduling Your Maintenance Crew on a 24/7 Operation
April 9, 2013
Before a company goes to 24/7 operations, they typically reserve the weekend for much of their maintenance work - run the equipment on the weekdays then shut down and fix everything on the weekends.
When a plant shifts to 24/7 operations, the first thought of maintenance people is “Where do we go now?” The weekend, their one time to do maintenance, is being taken up by production. Is this the end of preventative maintenance? Will maintenance now be restricted to small windows of opportunity such as line changeovers? And the biggest question is “How will we schedule maintenance people when we no longer know when we will have access to equipment?”
The answers to these questions are much simpler than most people anticipate.
To get to these answers we first need to break down maintenance into its three main components: (1) Corrective Maintenance, (2) Preventative Maintenance and (3) Project work. I will cover all three of these, and then use an example at the end.
On a 24/7 operation, everything is running all of the time. While there are plenty of exceptions to this (change-overs, sanitation etc.) we’ll consider production to be spread uniformly across all hours for this discussion.
Since corrective maintenance is not “scheduled”, it can be nearly impossible to predict with any accuracy. Therefore, we should consider an “event” requiring corrective maintenance to be random. That is to say, it is equally likely to occur at any time during the week. Under this type of condition, it is best to spread your resources around equally. From a corrective maintenance perspective, it makes no sense to staff differently on Saturday afternoons than on Wednesday nights.
When it comes to staffing levels, you will have to take into account things such as: (1) the likelihood of something breaking down, (2) the opportunity cost of delaying a repair (3) the cost of overstaffing when those people could be used more effectively elsewhere and (4) the availability of additional resources through callouts. The mistake most people make is to overstaff the corrective maintenance crews. They need to realize that they will never have enough people to always ensure there are enough people to handle every possible contingency. It is better to have an effective plan for augmenting your crew in an emergency.
This is actually easier to do on a 24/7 schedule that on a 5-day schedule. On a 5-day schedule, you are essentially committed to “pit stop” maintenance. You only have a very little window to fix everything so you throw all of your resources at it during that time. Hopefully, you get enough things fixed so the plant can run well the next week.
On a 24/7 schedule, you still have maintenance to do, but you no longer have to do it all on the weekend. Now you can spread it out during the week. As a maintenance person, you’d rather do preventative maintenance during the day shift on weekdays. Not only is this the preferred schedule for your people, it is also when you have the most resources available. On Monday through Friday day shifts, you will have greater access to vendors, parts suppliers and engineers.
This all points towards scheduling as much preventative maintenance as possible during Monday through Friday day shift. Of course, there should always be preventative maintenance assigned to other shifts throughout the week so maintenance people will be productive if there is no corrective maintenance needing their attention.
Project Work is like preventative maintenance in that it is best done during the weekdays when the most outside resources are available. Unlike preventative maintenance, project work often requires several consecutive days or weeks of work to be accomplished. It is best started, maintained and completed by the same people to minimize any loss of information during turnovers between crews. To do this, you will want to use 8-hour workdays where the project people come to work and advance the project every day, five days a week.
You will notice that the top schedule uses 18 people. It is most heavily staffed on the day shift. The three people on the night shift is a “signal” as to what the minimum acceptable staffing should be at any time.
Most companies that go to a 24/7 schedule will take the top maintenance schedule and just throw it away. They think that going from a 3-crew schedule to a 4-crew schedule means that everyone will go to the new schedule and that they need to add 33% more people. In this instance, that would mean a total staffing of 24 maintenance people (6 up from the original 18).
The reality is that maintenance is about to become more, not less efficient. Because of this, an increase of 33% does not make sense. (Note: most maintenance crews feel they are understaffed. While they may be right, my point here is that the schedule itself should not require an additional 33% staffing)
In the second schedule, I use 3 people as the minimum needed for corrective maintenance. I create a 4-crew 12-hour schedule and put 3 people on each of these crews. I then add 1 additional person and put a total to 7 people on the Monday through Friday schedule. These will be my preventative maintenance and project people. Where did I get the number of “1” for how many extra people I need? The original schedule shows that they are using 10 people on the day shift Monday through Friday. By putting 7 people on the Monday through Friday and adding the three that will also be there because of the 24/7 schedule, I end up with the 10 people I need.
Now, there will be overtime. Things will break down and people will have to be called it when it gets too bad. However, that is the nature of the beast if you have chosen a career in maintenance. The good news is that most weekends will now be freed up and most maintenance will take place where the most resources are available.
If you’d like to speak to one of our experts about your maintenance schedule, give us a call at (415) 763-5005.