- What is Total Productive Maintenance?
- What are the 7 Pillars of TPM?
- TPM + Lean Manufacturing
What is Overall Equipment Effectiveness (OEE)?
Improving OEE with TPM
Total Productive Maintenance Tools
Total productive maintenance is connected to Lean manufacturing in the grand scheme of workplace organization and waste elimination. While the stated goals of TPM are to keep productivity up and improve maintenance efforts in a facility, the end result is an area with far less waste. TPM works best in the manufacturing industry, but the method can be adapted for other work environments as well. With that being said, using a maintenance strategy like TPM is helpful for avoiding downtime and improving production results.
Some people believe that out of all the different Lean strategies used in manufacturing, total productive maintenance is the most difficult to fully implement. The difficulty can be attributed to TPM’s direct impact on every employee, machine, and piece of equipment in the workplace. Despite this, companies that have used this methodology agree that it is well worth the effort.
What is Total Productive Maintenance?
Total productive maintenance, or TPM, is a system that is used in an attempt to maintain and improve the integrity of a production process through small consistent improvements during preventative maintenance tasks. While TPM shares many of the same objectives as total quality management, TQM is more focused on meeting the customer’s needs by utilizing effective communication and data. Both are very different strategies, but each has their own merit when it comes to avoiding waste, providing quality product consistently, reducing costs, and minimizing defects.
When properly implemented, TPM will fully integrate the maintenance of machines and equipment into the overall manufacturing process. This strategy is used to help eliminate unplanned outages and downtime, losses associated with maintenance, and to normalize the thought that keeping machines in proper working order is not an interruption of work.
As a preventative maintenance ideology, TPM utilizes the metric Overall Equipment Effectiveness (OEE) to identify the manufacturing losses that are affecting production the most. At first it may seem as though placing a priority on preventative maintenance will lead to more frequent outages to conduct those maintenance tasks. However, that is typically not the case. In fact, the total number of outages is reduced with preventative maintenance, and the advantage of having those maintenance outages planned ahead of time results in a significant increase in productivity.
In the end, TPM will reduce waste in many forms including wasted time, wasted effort, inefficiencies, and even defects. While it will take a significant amount of work to properly implement the TPM methodology in a facility, the results can lead to significant improvements.
The Six Big LossesOne of the primary goals that total productive maintenance tries to achieve is the act of eliminating what are referred to as the “Six Big Losses.” These are the six largest contributors to productivity loss in industrial environments. All of them can be eliminated with appropriate TPM management techniques.
- Breakdowns – Determining how to fix downtime lies within finding the root cause of the problem. Without this data, along with knowing how much downtime there is and when it occurs, the facility will not be able to improve OEE.
- Setup and Adjustments – Changing from manufacturing one product to the next often takes time and it may even require the production team to adjust components to create an acceptable product. This adjustment often result in wasted product. With that being said, changeover is measured from the most recent correct product produced to the next correct product produced after the change has occurred.
- Idling and Minor Stoppages – Stop and go production is often hard to measure for improvement purposes. Use cycle time analysis in tandem with a form of automatic data gathering to help with measuring stop time.
- Speed Loss – Use the tools from the previous “big loss” to compare times with the current cycle time and the ideal cycle time in which product is produced.
- Defects in Process – During a steady production, defects that appear during that process are considered to be a waste since it requires extra time to fix or ruins material entirely. This is classified as a quality loss problem which is usually caused by wrong equipment settings and even human error.
- Startup Losses – Also classified as a type of quality loss, startup losses usually occur in instances of changeover from one product to another. It accounts for all the scrapped product that may result during adjustments.
To be clear, the point of reducing these “Six Big Losses” is to reduce breakdowns, prevents stop and go production, reduce defects, and minimize accidents. All of these problems are perpetrators of lost time and increased cost that hit productivity levels hard in the workplace. The ability to measure cycle times for improvement and provide machines the care they need to run without these hiccups are the key to a successful TPM strategy.
What are the 7 Pillars of TPM?
The total productive maintenance system is built on seven primary concepts, also called pillars. These pillars work together to help maximize system uptimes and ensure the right strategies are followed to get the most out of every production line. When all employees actively follow those TPM strategies, it’s possible to end up with exceptional results since the method is built on the foundation of full employee support.
The first pillar is autonomous maintenance and involves the people who regularly work with equipment. These employees are responsible for monitoring the condition of the area themselves. If they notice any worn or damaged components, they must report it in order to get it fixed immediately.
While scheduled maintenance is important and routine inspections are essential, nothing can replace the attention to detail that employees have when it comes to watching for problems. For example, someone who drives a high-low is going to notice when it’s riding rough or having other issues long before problems would be discovered using normal maintenance techniques.
This pillar is focused on making sure the right maintenance resources are being used on the correct objects at the right times. By addressing serious problems first and working down to minor annoyances that have no immediate impact, it’s possible to focus all efforts efficiently.
While it’s ideal to address every concern immediately when it comes in, most facilities don't have sufficient resources to get this done. For that reason, using focused improvement techniques can help ensure all problems are addressed appropriately.
The third pillar is preventative maintenance and involves addressing problems before they occur. There are many types of preventative maintenance that can take place, and facilities that have a strong focus on this pillar tend to have minimal downtime.
Creating a schedule of planned maintenance tasks is the job of team leaders, which they will then share with the front-line workers as well as the maintenance team. By keeping everyone informed on what is happening, and when, scheduled maintenance will be minimally disruptive to overall production.
Process Quality Maintenance
The pillar of quality maintenance upholds the goal of zero defects in the initial stage of production. Implementing high quality procedures for all the work that is done will not only make each individual more productive, but it can also help to reduce wear on machines and other equipment. Consider the fact that machines do the same thing every time and do it in the most efficient way possible. However, if employees from each shift are doing tasks a different way, there will be a higher rate of error involved.
As with almost all workplace improvement programs, TPM is going to require sufficient education and training for employees. This knowledge provides them with the tools that can help them understand what they need to do, and why. An effective total productive maintenance training program will include both initial education provided to new employees as well as continuous improvement training to help the facility enjoy ongoing benefits.
This pillar involves all the different administrative tasks associated with the total productive maintenance program in a facility. Gathering data and compiling it, issuing maintenance schedules, and much more can all help to maximize the efficiency and effectiveness of a TPM process.
The information that is gathered, compiled, and saved should be shared with the rest of the company.
Providing them with information can help the different teams see how their efforts are contributing to overall facility improvement. This pillar also helps to track data over time so it can be made clear just how effective a TPM system is.
Safety, Health, Environment
Implementing safety processes is another industry resource that will help to further reduce downtime and machines issues. One of the most important aspects of this pillar is that everyone needs to remember that safety concerns are the most important. For example, even if a dangerous machine is only having minor signs of problems, those problems could still lead to an accident or injury. With that being said, repairs on that machine should be placed at the top of the scheduled maintenance list.
TPM + Lean Manufacturing
Total productive maintenance is a form of preventative maintenance that Lean manufacturing encourages. TPM and Lean manufacturing both uphold the same objectives when it comes to waste elimination and facility efficiency, which is why they work so well together. This particular maintenance strategy is usually used alongside other Lean manufacturing techniques to create a well-rounded and efficient Lean manufacturing system.
Root Cause Analysis
Root cause analysis, also known as the “five whys,” is one of those tools in a Lean manufacturing program that can be used alongside a TPM program. RCA was specifically created to be a tool used for problem solving via identifying the root cause of production failures. There are a few steps to this process:
- Identify the problem and describe it in depth.
- Collect pertinent data.
- Ask why and establish the timeline from when it was working up to the precise time that something went wrong.
- Use event correlation to distinguish root causes from other factors.
- Identify and implement any solutions.
- Make sure to check back in to see if the solution has been successful.
The 5S system
The second useful strategy that aligns perfectly with TPM is 5S. By putting focus on workplace organization and visual safety, workers will be able to pick out areas that are big contributors to wasteful activity. 5S already assists with:
- Asset management objectives
- DOWNTIME waste elimination
- Safety and productivity improvements
By using tools such as root cause analysis and 5S alongside TPM, the company will benefit from a well-rounded Lean manufacturing program.
What is Overall Equipment Effectiveness (OEE)?
OEE is a numerical tool used to measure and calculate a facility’s productivity by determining how much loss exists within the specified manufacturing process. There are three variables that are significant for the overall OEE measurement, and those are:
- Availability, also known as uptime,is the total amount of time that a production line has during shifts. This value is calculated by taking the run time and dividing it by the planned production time
- Productivity is the speed at which a machine is able to operate by and accomplish its tasks. The value is calculated by taking the ideal cycle time and multiplying it by the total count, then that number is divided by the run time.
- Quality is the number of items produced in comparison to the number that were actually sellable. This value is calculated by taking the total number of successful products made and dividing that by the total number of products created.
Once all those variables are found, the final calculation looks as such:
OEE = Availability x Performance x Quality
To make calculating this numeric value it a bit easier, Creative Safety Supply has an OEE calculator here to use.
Improving OEE with TPM
Overall equipment effectiveness is the driver within TPM programs. As was mentioned earlier, TPM is a strategy that aims to eliminate waste and wasteful behavior. With that being said, wasted time and wasted product are the largest catalysts that OEE suffers from. Therefore, if efforts are made to keep equipment in good shape before unplanned downtime occurs, then the OEE will be affected positively. This is because there will be more time being spent producing quality products and less time waiting for machines to get up and running after breakdowns.
Total Productive Maintenance Tools
It’s technically possible to use TPM in a facility without any extra expenses or other requirements. There are, however, many tools that can be used when implementing TPM to help improve the system’s effectiveness. Using the right tools can streamline many processes and help generate better results than would otherwise be possible. The following are some of the different types of tools that can be used:
- Inspection Cards - TPM inspection cards can provide a visual indicator of when something has been inspected, by whom, and what type of maintenance may be needed.
- Tags - When a problem is found that needs maintenance, TPM tags can be applied to the area in question so that the maintenance team knows exactly where to go to complete their job.
- Training Guides - There are a variety of different types of training guides available to help get employees up to speed with regards on how TPM should be used in a facility.
- TPM Forms - Having standard forms that are filled out when completing TPM inspections or other related work is a good way to ensure standard information is gathered and kept. This can then be used to plan for long term improvements.
As can be seen here, there are many different types of TPM tools that can be used in a facility. Some of the tools are made specifically to help with TPM, and others are more generic tools that can be used for a number of applications. Facilities looking to successfully implement a TPM strategy can invest in all these tools or add new ones over time depending on their budget and other factors.