- Posted on
- Riley Draper
Predictive and preventive maintenance both focus on improving asset efficiency and increasing its reliability. However, they both adopt various approaches to achieve these. Knowing the difference between both asset maintenance practices is a great starting point to know which of the two is best for your business.
Below, you will find everything you need to know about the similarities, differences, pros, and cons of preventive and predictive maintenance.
Predictive And Preventive Maintenance: The Overview
Predictive maintenance and preventive maintenance are maintenance strategies implemented as part of an asset management plan. Although both maintenance strategies feature different modes of operation, they are both designed to increase the reliability of assets within a business.
Every business is aware of the importance of asset maintenance. Without proper maintenance, assets will experience downtime, have frequent breakdowns, and become inefficient. For businesses that depend on physical assets such as machines and equipment to carry out every operational task, the breakdown of a machine is detrimental to production.
This explains why the world’s largest manufacturers lose almost $1 trillion annually due to machine failures. Machine and equipment failures are usually due to improper asset maintenance. Without servicing, cleaning, and inspection, machines will deteriorate.
This will affect their performance and, essentially, the business organization’s performance. However, as businesses try to provide assets with the necessary maintenance services they need, they are quickly faced with the complexities of the whole process.
The process of overseeing the maintenance of several assets in an organization is usually fraught with the problems of clashing maintenance schedules, knowing the best period to provide maintenance services, and trying to minimize maintenance costs.
To avoid unexpected breakdowns, unplanned downtime, and costly repairs but still give their assets the maintenance services it needs, businesses adopt a maintenance strategy. This helps them find a routine for fixing an asset, thereby preventing over-maintenance.
Predictive and preventive maintenance are two types of maintenance strategies usually adopted in organizations.
What Is Predictive Maintenance?
Predictive maintenance (PdM) is a proactive maintenance strategy that uses data analysis tools and techniques to detect faults and defects in a piece of equipment. It uses technological devices and processes to monitor the performance of an asset during its normal operation to note when the asset experiences a fault.
By monitoring an asset during its normal optimal performance, predictive maintenance makes it easier to spot anomalies and defects in operations. This reduces the likelihood of downtime as no fault goes undetected for a long time.
PdM was created by C.H. Waddington and was implemented in industries in the 1990s. At first, it was adopted with an offline approach and was restricted to certain fields that use heavy machinery, such as aeronautical engineering.
However, as technology advanced, so did preventative maintenance processes. Soon, this maintenance strategy was embraced in various business sectors. Predictive maintenance is often described as a condition-based machine maintenance program.
This is mostly because it cannot exist without continuous condition monitoring of machines during normal operation. By continuously monitoring, assessing, and measuring the optimal functional range of an asset, predictive maintenance reduces maintenance frequency while keeping equipment failure at bay.
How Does Predictive Maintenance Work?
Predictive maintenance combines the power of artificial intelligence (AI), machine learning (ML), and the Internet of Things (IoT). It uses these and many other technological tools to get insight into how a machine performs.
The process involves modern condition-monitoring devices- such as IoT sensors- connected to a single AI-powered system. These sensors collect performance data, such as temperature and conductivity, from and store the data received in asset management software.
Condition-monitoring sensors can quickly sight a deviation or anomaly from the data they collect. These anomalies are warning signs that something might be wrong with the operated machine. When technicians discover a change in machine parameters, they can quickly assemble a predictive maintenance protocol and schedule a maintenance service.
Essentially, PdM is a great way to predict unplanned downtime, making it easier to provide the necessary maintenance services before total machine failure.
Types of Predictive Maintenance
Different types of predictive maintenance procedures can be applied to various assets. These types include:
1. Vibration Analysis
Vibration analysis monitors the changes in a machine’s vibrations. The sensors monitor the asset’s vibrational level and trigger an alert when a change occurs. Vibration Analysis is typically used for high-rotary machines.
It detects machine imbalance, looseness, misalignment, and bearing wear. This type of predictive maintenance has been around for a while and is easily one of the most cost-effective processes in this strategy.
2. Acoustic Analysis
The acoustic analysis uses sound to detect faults in machines. It is popularly used for low- and high-rotating machines that require lubrication. Acoustic analysis listens to the inner works of a machine. It is easy to implement and makes a cost-effective maintenance strategy.
Acoustic analysis can be sonic or ultrasonic. While the sonic approach uses a strictly proactive strategy, the ultrasonic approach quickly detects subtle sound and is used mainly for predictive purposes.
3. Oil Analysis
Mostly used in the transportation industry, oil analysis involves extracting and testing the oil from a machine. This process tests for wear particles, the presence of water, and viscosity, using the data to determine the discrepancies in the machine’s performance over time.
4. Infrared Technology
Infrared Analysis is the most subtle yet efficient type of predictive maintenance technology. It relies not on sound or vibration but on the machine’s temperature. This makes it perfect for a wide range of equipment. Infrared technology recognizes and measures hot spots on a machine.
It makes it easy to identify problems due to cooling, airflow, and even engine stress.
5. Motor Circuit Analysis
Motor Circuit Analysis monitors a motor’s stator and rotor. It then uses the data collected to determine and detect faults. Motor circuit analysis as a predictive maintenance strategy is used in many industries, including the automotive industry.
What Is Preventive Maintenance?
Preventive maintenance is a maintenance plan that involves performing regular maintenance on assets. This form of maintenance strategy emphasizes the need for consistency. Essentially, preventive maintenance focuses on performing regular maintenance tasks regularly and at regular intervals.
Preventive maintenance focuses on scheduling consistent time-based machine maintenance services to eliminate the risks of failure. By consistently offering the machine all the attention it needs, preventive maintenance ensures machines are in tip-top shape, remain reliable, and suffer little to no downtime.
How Does Preventive Maintenance Work?
Unlike predictive maintenance, which is scheduled based on asset conditions, asset performance, and the real-time data extracted from the assets, preventive maintenance uses constant check-up services. It focuses on continuously fixing assets to avoid potential breakdowns instead of using corrective maintenance to fix the asset after it breaks down.
Essentially, preventive maintenance decreases the risk of asset damage by providing constant maintenance services to prevent potential problems.
Types of Preventive Maintenance
There are various types of preventive maintenance. Each type has its unique approach to keeping assets fully functional and reliable.The four main types of preventive maintenance include:
1. Usage-based Preventive Maintenance
Usage-based preventive maintenance focuses on scheduling regular maintenance according to how the asset is used. The more an asset is used, the more attention that machine gets during preventing maintenance.
When a machine is used too often without getting the necessary maintenance services it needs, it is prone to a breakdown. Usage-based maintenance services prevent equipment failures by providing regular inspection and maintenance services for these machines to avoid overworking them.
Although usage-based preventing maintenance can be used for any machine, it is often reserved for machines with high production cycles without an automation system. From vehicles to production machines, using this preventive maintenance plan ensures the reliability and continuous efficiency of a machine.
2. Time-based Preventive Maintenance
Time-based or calendar-based preventive maintenance schedules routine maintenance services based on a time interval. It is often used for low-priority machines that do not necessarily perform daily high-operational duties.
Time-based preventive maintenance is triggered when the due date approaches. By creating a schedule of when assets receive maintenance, businesses can allocate time and resources.
3. Predictive Maintenance
Predictive maintenance as a part of preventive maintenance advanced maintenance method. It uses Internet of Things (IoT) sensors and machine learning software. The sensors are attached to machines to continue reading their operational parameters using metrics such as temperatures.
Once a sensor detects an abnormality, a work order, the CMMMS generates a work order and assigns it to a technician.
4. Prescriptive Maintenance
Prescriptive maintenance takes predictive maintenance one step further using machine learning software. This software analyzes equipment conditions over a period to assess risk and makes maintenance recommendations that are even better than generic manufacturer guidelines.
Essentially, prescriptive maintenance makes it possible to track variable operating conditions up to the time of failure. This makes it possible to hypothesize potential outcomes that may lead to equipment failure.
Predictive vs. Preventive Maintenance
Predictive maintenance and preventive maintenance are two very different maintenance management strategies. While they may not be entirely mutually exclusive, these maintenance processes have different approaches, features, advantages, and disadvantages.
The major differences between predictive and preventive maintenance include the following:
Although they have the same goal of increasing asset lifespan, minimizing equipment failure, and increasing asset reliability, predictive and preventive maintenance adopt different approaches to achieve this goal.
- Predictive Maintenance: Predictive maintenance is considered to be a proactive type of maintenance. It is a condition-based maintenance system where the condition of an asset determines when the maintenance service will be provided. If there is a deviation from one of the parameters considered normal in that asset, a maintenance service will be provided.
- Preventive Maintenance: Unlike predictive maintenance, preventive maintenance aims to provide regular and timely maintenance services, regardless of the state of the asset. It involves regular cleaning and repair services from a maintenance team, intending to keep the piece of equipment in optimal condition. The maintenance services are usually planned, e.g., monthly, every first week, or every few months.
Another main difference between the predictive maintenance approach and preventive maintenance is the timing of the maintenance management service.
- Predictive Maintenance: This is done anytime the sensors spot a change in the machine’s performance that may mean a problem or a piece of faulty equipment. It is irregular and depends on the state of the asset and its real-time condition.
- Preventive Maintenance: This is usually scheduled at a predetermined time and is usually a regular routine. Preventive maintenance may be scheduled monthly, quarterly, or even annually.
When it comes to implementing predictive and preventive maintenance strategies, it is essential to remember that they give varying degrees of difficulty. This is due to the difference in their operation and the kinds of equipment they need.
- Predictive Maintenance: A predictive maintenance strategy is a complicated process. This is because it uses AI, ML, and other forms of technology to study assets. As a result, it is more demanding, arduous, and complex to implement.
- Preventive Maintenance: Preventive maintenance program is a more straightforward process. Although some maintenance workers may use technological devices during preventive maintenance, the process still requires less equipment than predictive maintenance.
Predictive and preventive maintenance strategies have different methods of keeping assets in great condition.
- Predictive Maintenance: It does not require a sign of fault. Predictive maintenance monitors the state of assets to spot signs of faults and potential problems quickly. Regardless of what this sign is, there is going to be an anomaly in the asset or a change in the asset’s performance before a predictive maintenance service can be scheduled. Essentially, predictive maintenance uses a proactive approach.
- Preventive Maintenance: Preventive maintenance is scheduled regularly, regardless of the presence of signs of a fault or not.
Optimizing costs while adopting a maintenance strategy is essential for any business. Knowing which maintenance strategy best fits your budget is key to creating the best maintenance program.
- Predictive Maintenance: Predictive maintenance requires various technological solutions, including ML and AI. As a result of the costs of acquiring these solutions, predictive maintenance is more expensive and will require more capital to be implemented in a business. However, after it is installed, predictive maintenance is a cost-effective maintenance strategy that requires less money to be sustained.
- Preventive Maintenance: It requires fewer technological devices and add-ons, making it cheaper to be integrated into an organization, especially a small business. However, consistent maintenance raises costs, making preventive maintenance the more expensive option in the long run.
6. What It Does
Preventive and prescriptive maintenance protect assets. However, where one predicts asset failure, the other works wirelessly to avoid all of the signs of breakdowns.
- Predictive Maintenance: This type of maintenance management prevents asset downtime by predicting when the asset will need maintenance.
- Preventive Maintenance: This type of asset maintenance focuses on preventing asset damage and breakdowns by scheduling and performing timely maintenance services or replacements.
7. How It Uses Resources
Predictive and prescriptive maintenance use resources differently. The main difference between both include the following:
- Predictive Maintenance: This maintenance approach strictly schedules maintenance services based on the condition of the equipment. This ensures every resource dedicated to providing maintenance service is needed and implemented when necessary.
- Preventive Maintenance: Preventive maintenance is done regardless if the machine needs it or not. This usually results in unnecessary maintenance and the use of resources that could have been spared for more important repairs.
Which Maintenance Strategy Is Best?
Predictive and preventive maintenance share the same goal of reducing asset lifetime while keeping assets in optimal condition. However, they both adopt very different ways of meeting this goal. Although these maintenance programs may differ, they both make good asset management options.
Knowing what the basics of each maintenance program are will make it easier to pick the right one for your business.If You Like Please Share It: