Maintenance is designed to increase the reliability of machinery and reduce the number of times you have to act reactively to failures. Thus, maintenance is an integral component of manufacturing equipment operation.
Preventive and predictive maintenance are the routes that the vast majority of companies choose for industrial maintenance. This is logical, considering that the other possible alternative is none other than corrective maintenance, which deals with parts only after they have broken down.
The main differences between preventive and predictive maintenance are as follows.
Preventive maintenance is performed periodically, regardless of whether or not each time maintenance is actually necessary. Preventive maintenance is designed to keep parts in good condition, but it does not, however, take into account the condition of a component or a process.
Predictive maintenance, on the other hand, occurs on an as-needed basis, based on real-time collection and analysis of machine operating data to identify problems at an earlier stage, before production has to be interrupted. With predictive maintenance, repairs occur during machine operation and resolve an actual problem. If a shutdown needs to be performed, it will take less time and be more localized.
While planned downtime in preventive maintenance can be a problem and represents lower overall capacity availability, it is preferable to the unplanned downtime of corrective maintenance, where costs and duration are almost always unknown until diagnostics are performed and the problem is addressed.
Preventive maintenance
Preventive maintenance is the most popular of all. This maintenance is planned over time. What underlies the concept of preventive maintenance is the taking of measures on a regular basis to prevent problems before they occur. Thus, preventive maintenance has the following characteristics:
-It is planned at regular intervals.
-It requires downtime on the part of the machine in order to be carried out, although this downtime is scheduled and planned.
-Often consists of a checklist that includes inspection, calibration, cleaning, repair and replacement of equipment and components.
-It can be implemented at different intervals. Your facility may have a daily regimen of cleaning and inspection of the machine at the beginning and end of shift cycles, however, it may also happen that the checks are semi-annual or annual and more comprehensive.
-It is carried out even if there are identifiable problems.
Essentially, preventive maintenance is a collection of best practices and historical statistics that focuses on an identified interval that provides the best chance of detecting problems before they arise. It continues to be used because it is so effective for many companies.
Predictive maintenance
Predictive maintenance is a clearly growing field with connectivity and data collection options continuing to develop steadily. Like preventive maintenance it has a proactive approach.
The main difference between preventive and predictive maintenance is that predictive maintenance uses monitoring equipment to evaluate machinery performance through a more real-time, data-driven approach, and therefore identifies the potential for problems before they occur.
Just as preventive maintenance relies on best practices and historical data, predictive maintenance takes measurements of machine operations as they occur and uses this data to generate warning signals when indications of a problem are detected. Predictive maintenance could be summarized by making the following assertions:
-It is proactive
-It can be carried out while machines are operating in their normal production modes.
-Identifies and addresses potential problems, allowing maintenance to occur before a breakdown occurs.
-It relies on interconnected data collection and measurement systems, as well as tools and workers to analyze that data.
Predictive maintenance vs. preventive maintenance
Each of the maintenance approaches has advantages and disadvantages based on the qualities previously identified. In addition, it should be noted that since these are two alternatives with proactive approaches, some of the benefits clearly overlap.
The clear benefits are that it is proactive, limits unplanned downtime, increases equipment life and is efficient, especially with experienced personnel.
On the downside, it may be addressing problems that do not actually exist as maintenance occurs regardless of the problems identified, requires more extensive inventory management for replacement components, and increases planned downtime.
Among its benefits are proactivity, identification of real problems early on so they can be addressed, reduced downtime, improved inventory efficiency where parts are not replenished until they fail, but are also not replaced while they are still usable, and finally, it offers extensive options for maintenance practices based on real-time analytics.
The main disadvantages are that it is more complex than preventive maintenance, not as scheduled as preventive maintenance as downtime can be considered unplanned, although it is shorter and more efficient, it may require new equipment and technology infrastructure to collect and share data with a centralized system, and finally, it may require extra staff or more training of existing staff.
