A Guide to Preventive Maintenance: What Is PM & How Does It Work?

Preventive Maintenance is a maintenance approach used to strategically maintain, repair, and replace equipment before a costly breakdown occurs. This strategic method allows businesses, that are reliant on their equipment and heavy machinery, to improve uptime and prolong the operating life of their assets.

For simple preventive maintenance tasks, time-based and interval-based maintenance techniques are used. For more complex tasks, a combination of time-based, interval-based, and condition monitoring activities are undertaken. All of these are accelerated with the use of a capable maintenance management solution, such as CMMS Software.

Implementing the right maintenance strategy helps reduce the likelihood of unplanned downtime, which, In 2005, cost the automotive industry alone $22,000 every minute. With 82% of companies experiencing unplanned downtime at least once in the last three years, implementing a preventive maintenance management plan should be of top priority for maintenance leaders.

What Is Preventive Maintenance?

Preventive Maintenance (PM), also referred to as Preventative Maintenance, is a proactive maintenance strategy that involves regular and routine maintenance of equipment to reduce the likelihood of failure leading to unplanned downtime. Through scheduled cleaning, repairs, adjustments, and part replacements, a preventive approach increases the availability and operational output of equipment and machinery.

Like other strategies, preventative maintenance can be beneficial when deployed under the right conditions. For instance, you may identify a machine that is critical to your production process. Preventive maintenance, such as cleaning air filters and changing oil lubrication, can be performed on this machine whilst it is still operational. Thus avoiding machine failure leading to downtime and a delay in production.

Companies Experiencing Unplanned Downtime 2014-2017*

• 82%18%

*Outages lasted an average of 4 hours and cost an estimated $2 million (Vanson Bourne Study, 2017)

For businesses without a proactive approach to maintenance, running an asset to the point of failure can cost them up to 10 times more in repairs and lost production than companies with a planned maintenance strategy.

When deployed alongside a computerised maintenance management system (CMMS), PM offers much more than simply performing routine maintenance. It allows you to collect data recording breakdowns, repairs, and services, enabling you to perform Root Cause Analysis (RCA) and quickly identify the cause of future faults. You can then record the typical life expectancy of each of your assets and understand when equipment needs replacing or disposing of.

Preventive Maintenance vs. Reactive Maintenance

Whereas preventive maintenance is a strategy for planning routine repairs and services, reactive maintenance is the opposite. Referred to as breakdown or run-to-failure, reactive maintenance is the process of repairing equipment only once it has failed. Although this can be cost-efficient when practised on assets with minimal repair costs, it can be damaging to production and your company’s bottom line.

Advantages of Reactive Maintenance Over Preventive Maintenance

• Minimal start-up fees and low up-front costs
• No need to plan maintenance schedules
• Less maintenance staff required

Disadvantages of Reactive Maintenance Over Preventive Maintenance

• Increase in unplanned downtime of critical equipment and machines
• Causes delays in production
• High emergency repair and replacement costs
• Assets have a shorter life expectancy when not kept in optimal working condition
• Reactive maintenance has a 40% higher cost expectancy when compared to PM

Types of Preventive Maintenance

Although there are three definitive maintenance groups – Reactive Maintenance, Preventative/Preventive Maintenance, and Predictive maintenance (PdM) – each group has a branch of further maintenance types. For example, Emergency and Breakdown Maintenance strategies sit within a Reactive approach.

In terms of Preventative Maintenance, it incorporates the following types of maintenance:

Time-Based Maintenance (TBM)

Time-Based Maintenance is an approach most commonly deployed for equipment that is essential to your operations. It involves planned maintenance that can be triggered daily, weekly, monthly or annually to ensure equipment remains in optimal working condition.

Usage-Based Maintenance (UBM)

Usage-Based Maintenance is typically saved for assets that are used daily. By setting usage-based triggers, maintenance managers and technicians will be alerted to when a piece of equipment needs servicing. Usage-based alerts can be triggered after a certain amount of operating hours, miles, or production cycles. For example, a vehicle may need to be serviced every 10,000 miles.

Failure-Finding Maintenance (FFM)

Failure-finding maintenance is a type of maintenance that can be both unique to itself as well as a type of preventive maintenance. A failure-finding approach refers to an inspection that is carried out to discover defects or failures in an asset. For example, a malfunction in a smoke alarm will never be identified until that alarm is triggered.

When to Deploy Preventative Maintenance

With the acquisition of extra resources such as staff and spare parts, deploying preventive maintenance can be an expensive investment. But, when compared to other strategies, it is a cost-effective approach that can save you thousands of pounds each year in repair and replacement costs. This is particularly true for industries that rely heavily on the availability and reliability of their assets. These industries include:

• Hospitality
• Healthcare
• Manufacturing
• Oil, Gas, and Utilities
• Governments
• Education
• Facilities
• Fleets

As well as managing the uptime of hundreds of assets, there are other factors that should also be considered when it comes to implementing the right maintenance strategy. For example, it’s best to deploy preventive maintenance if you’re experiencing:

• A delayed production schedule due to asset failure and unplanned downtime
• Expensive emergency/breakdown repair costs
• A high turnover rate of expensive equipment
• A delay in receiving spare parts due to a lack of inventory management

Although deploying this strategy will provide the tools necessary to optimise the upkeep of your assets, there is also the risk of excessive preventative maintenance. This is when a PM approach is applied to assets of low value or priority in the production process such as lightbulbs.

Benefits of Preventive Maintenance

The process of scheduling routinely planned maintenance is critical for organisations that rely on their assets for revenue. This is why preventive maintenance is an approach most asset-reliant companies choose over other strategies such as reactive maintenance. The advantages of preventative maintenance include:

• Reduced unplanned downtime
• Fewer breakdowns of equipment and machinery that are essential for production
• Improved reliability of mission-critical assets
• Fewer expensive corrective and emergency repairs
• A prolonged life expectancy of assets results in a lower turnover rate
• Improved RCA data collection
• Increased safety and reduced risk of injury

Downsides of Preventive Maintenance

Although deploying preventative maintenance will reduce downtime, there are some considerations when taking this approach. Disadvantages of preventative maintenance include:

• Possibility of excessive preventive maintenance
• High start-up and implementation costs
• Need for more resources (spare parts, staff, etc.)
• Can be time-consuming

Creating a Preventive Maintenance Plan

The benefits of deploying preventive maintenance to decrease downtime are clear. But, where do you start? Once you’ve settled on implementing the right maintenance approach for your operations, it’s time to create an effective preventative maintenance plan.

Step 1: Highlight End Goals

The key to understanding if a preventive maintenance strategy works for you is to first highlight the goals you want to achieve. Do you want to:

• Reduce downtime
• Reduce repair costs
• Increase asset availability
• Improve inventory management
• Increase production rate

Step 2: Choose a Platform

You should now decide which format you’re going to use to achieve your preventative maintenance goals. The top three methods for performing maintenance management are pen-and-paper (39%), spreadsheets (52%), and CMMS (63%).

With the influx of affordable, easy-to-deploy, and user-friendly digital solutions that are available in today’s market, there’s no reason why any organisation shouldn’t choose a CMMS to deploy preventative maintenance. A CMMS allows small and medium businesses (SMBs) and large enterprises to easily automate their maintenance management.

Step 3: Build an Asset Register

In order to build an effective maintenance plan, you need to identify all of your assets. This includes the equipment and machines that are critical to your operations. When mapping out your assets, group them into categories that can help your maintenance team easily identify them. Such as:

• Location
• Priority
• Family (for example, air conditioning will be grouped into the HVAC maintenance family)

If you choose to deploy a CMMS solution, you can also combine the use of IoT asset tags. This not only allows you to track all assets with greater accuracy, but it can be time-efficient when compared to methods such as spreadsheets. A CMMS also allows you to attach important documentation, user manuals, manufacturer recommendations, warranties, and compliance standards to all assets.

Step 4: Identify Critical Assets

With limited time and resources, scheduling all assets from your register into a preventive maintenance plan can be overwhelming. Instead, identify the assets that are critical for your operations.

Choosing just one or two priority assets to establish your preventative maintenance plan offers a more manageable approach and acts as a testing ground for future planned maintenance. As well as making it easier to determine your Key Performance Indicators (KPIs) and what ROI you expect from each asset.

Step 5: Determine KPIs

Setting Key Performance Indicators is key to understanding if your preventative maintenance plan is effective and producing the right results. Typical maintenance management KPIs include:

• Achieving 99% annual uptime of a critical asset
• Eliminating all unplanned downtime for 3 years
• Increasing inventory and spare parts stock accuracy to 90%
• Reduce annual workplace accidents to under 2%

KPIs can be set either after critical assets have been identified or at the very beginning of the processes when you’re getting buy-in from stakeholders.

Step 6: Create a Preventive Maintenance Plan

Once you’ve aligned your priority assets and set your KPIs, it’s time to drill down and start implementing your preventive maintenance plan. Using an effective maintenance management tool, you can begin to schedule maintenance for both the short-term and long-term. This process includes:

• Assigning the right maintenance personnel (technicians, managers, engineers, electricians, etc.)
• Assigning tasks
• Prioritising work orders with due dates and condition-based metrics
• Automating work orders through CMMS

KPIs can be set either after critical assets have been identified or at the very beginning of the processes when you’re getting buy-in from stakeholders.

Step 7: Track, Review, and Adjust

A trap that many maintenance teams and production managers fall foul of is not reviewing their preventive maintenance plan. By not monitoring schedules and leaving planned maintenance to stagnate, opportunities can be missed and ROI can decrease. To track and monitor your plan effectively, be sure to:

• Regularly check manufacturers’ recommended procedures, which can be updated regularly
• Use collected data and personal experience to tweak work orders
• Review the performance of technicians and maintenance teams

By reviewing these factors, you’re able to make small adjustments to your maintenance plan and avoid the risk of failing to meet your KPIs.

Types of Maintenance Strategies

Although 80% of maintenance personnel favour a preventive maintenance approach, there are other types of maintenance strategies that can suit various industries and operations. Other maintenance types include:

Reactive Maintenance

A reactive maintenance strategy (also referred to as breakdown or corrective maintenance) is a process of repairing equipment only when it has failed. Although this approach can result in excessive breakdown repair costs and unplanned downtime, it is a recommended approach for 10% of your asset inventory.

Predictive Maintenance (PdM)

Predictive maintenance is the practice of gathering analytical data from sensors and IoT devices, storing it in a maintenance management system, and predicting when assets will fail. Predictions are based on monitoring asset conditions with the aim to identify maintenance before failure.