Scheduled Maintenance

Everything you ever needed to know about scheduled maintenance.

(Free) Essential Guide to CMMS

What is scheduled maintenance?

Scheduled maintenance is any pre-planned maintenance work that must be completed by a specific person or group within a set timeframe. Examples of scheduled maintenance include tasks that occur at regular intervals like replacing air filters, performing oil changes, or conducting routine inspections. You can also coordinate scheduled maintenance for planned work that only needs to occur once.

Scheduled maintenance may or may not include planned downtime. Some maintenance activities like vibration monitoring can be done on machines in active operation. Others, like rewinding an electric motor, require a full equipment shutdown.

Scheduled maintenance vs. planned maintenance

Scheduled and planned may sound like the same thing, but don’t let that fool you. In the context of maintenance activities, they have distinct meanings. You have to plan maintenance before you can schedule it. 

Planned maintenance refers to the end-to-end process for executing maintenance work. Planning includes identifying maintenance tasks as well as the tools and workflows necessary for tackling them. It’s all about figuring out what your team needs to do, why they need to do it, and how they’ll do it. Different types of planned maintenance strategies include predictive and preventive maintenance which aim to make businesses more proactive.

Scheduled maintenance involves defining timelines and assigning responsibilities for completing maintenance work. Unlike planning, scheduling is ultimately about the who and the when of completing tasks. Organizations may include scheduled maintenance tasks as part of their overall planned maintenance program or schedule tasks through a separate, simpler workflow

Checklist for Creating a Preventive Maintenance Plan

Following a consistent Preventive Maintenance Plan can make life easier. Use this checklist to create your own!

What is unscheduled maintenance?

The term “unscheduled maintenance” does not refer to maintenance tasks that pop up unexpectedly. That is unplanned maintenance. Unscheduled describes maintenance tasks that don’t have established timelines and have not been assigned to specific employees, but need to happen nonetheless. 

Here’s an example. Imagine you’ve purchased a new piece of machinery that requires maintenance after every 100 hours of operation. You’ve never encountered this type of machine before and you don’t yet know how long it will take to reach 100 operational hours. 

You can get a plan together by estimating the cost of maintenance, creating a checklist to guide technicians through the process, and securing the necessary parts. You cannot, however, schedule the maintenance. You won’t know when the machine needs service or how long this service will take until it reaches 100 hours of operation. Until you have the necessary data, you’ll have a maintenance plan without a maintenance schedule.

Different types of scheduled maintenance

Maintenance scheduling may depend on any one of a number of factors. Two popular types of maintenance include: 

  • Time-based maintenance: This type of preventive maintenance sees businesses build schedules for carrying out tasks at regular intervals. You might service an asset on a monthly schedule or after it has spent a certain number of hours in operation.  
  • Condition-based maintenance: This type of preventive maintenance involves building schedules around the working condition of critical assets. Assets are scheduled for maintenance once certain indicators show that performance has diminished or that failure is likely.

The benefits of scheduling maintenance

Taking the time to strategically plan and schedule maintenance tasks pays off: 

  • Reducing unplanned downtime: Planning and scheduling your maintenance work ahead of time decreases the likelihood of unexpected equipment failure and the costly downtime it can cause. 
  • More efficient personnel utilization: Strategically scheduling and assigning tasks based on ability, location, and other details ensures your maintenance team is effective and efficient.   
  • Increasing the lifespan and lifetime value of assets: When you stick to a maintenance schedule, machinery suffers fewer breakdowns, lasts longer, and holds a higher value in the resale market.

Establishing a culture of proactivity: Scheduling maintenance as part of a strategic, end-to-end maintenance plan reinforces the value of caring for company assets. 

What is the Scheduled Maintenance Critical Percent (SMCP)?

In an ideal world, all maintenance tasks would occur right on schedule and exactly as planned. Here in the real world, it is never so simple. Maintenance professionals are often pulled in different directions, with urgent needs that often arise with little warning. 

With such competing priorities, how do you know which tasks need your attention the most? Rather than search through backlogs of maintenance histories or other manual processes, it is better to use an objective way to prioritize tasks. By calculating the scheduled maintenance critical percent (SCMP) of all overdue tasks, teams can rank – and prioritize – them accordingly. 

How to calculate SMCP

The scheduled maintenance critical percent is basically a way to summarize in one number, how late a task is, relative to when it is due. To calculate the SMCP for a task, you first need to know how many days overdue it is. Next, you add this number to the total number of days in the typical routine or recurrence of this task. After dividing this sum by the total number of days, you multiply the quotient by 100 to get a percentage. This figure gives you a sense of the task’s criticality.

Scheduled maintenance critical percent formula

For example, imagine two overdue maintenance tasks. The first occurs on a 30-day maintenance cycle and is three days overdue (SMPC=110%). The second is five days overdue and is scheduled to take place every 60 days (SMCP=108%). The first task has a higher SMCP and therefore needs your attention first. 

Why Track Scheduled Maintenance Critical Percent?

Overseeing a plan and schedule for maintenance work often means making quick judgments to organize priorities. SMCP helps maintenance professionals quantify the importance of different maintenance tasks to more efficiently budget time and allocate resources while reducing excess costs and downtime.  

  • Improved scheduling: With insights into the impact of individual work orders, you’ll better understand which tasks need immediate attention or service from multiple technicians.
  • More proactive maintenance: Over time, SMCP can provide data on which of your business assets regularly take too long to service. These assets may be the same ones that are most likely to experience sudden failure and require reactive maintenance. 
  • Simplified auditing: Leaving tasks incomplete could mean failing an internal or third-party audit. By keeping your backlog of overdue tasks handy and quantifying the importance of each task, you’ll have an easier time intervening before a small issue becomes a safety threat.

SMCP is a critical metric for any maintenance operation, but it’s not without its shortcomings. Relying on SMCP alone would mean failing to take into account other important factors. Maintenance managers should also consider things like the availability of technicians with the specific skills needed for completing a task, the criticality and operating schedule of the asset in question, and regulatory constraints that dictate maintenance activities, among other factors. 

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CMMS for scheduled maintenance

If the calendar on your wall is still the most advanced scheduling tool at your disposal, it may be time for a change. Computerized Maintenance Management Systems (CMMS) simplify, centralize, and automate many of the processes associated with servicing and maintaining all of your critical business assets and make the scheduling process a breeze. Learn more about how to evolve beyond paper and pencil and what it could mean for your organization in our guide to CMMS.  

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