Uptime: TPM — A Foundation for Asset-Management Systems, Part I
Bob Williamson | August 28, 2014
If you cannot make Total Productive Maintenance work in your plant, you will surely struggle with the ISO 55000 Asset Management Standard.
Total Productive Maintenance (TPM) is an organization-wide process for improving equipment effectiveness that was taken from the heart of what we now know as the “Toyota Production System” (TPS). TPM came to North America from the Japan Institute for Plant Maintenance (JIPM) in the mid-1980s. The TPM process gained momentum because of the way it shared equipment-maintenance responsibilities with others in organizations through fundamental “pillars.” The Pillars of TPM outlined the basic principles of the process and how they were to be deployed interdependently (they supported each other).
TPM’s basic pillars
From the onset of TPM in North America and through its first 10 years, we knew it could become the predominant equipment-maintenance strategy for the 21st century. Why? TPM offered a fresh insight to equipment maintenance and reliability that went well beyond the confines of maintenance departments’ roles and responsibilities.
TPM is not just another maintenance program. Others in the organization had to become involved because TPM focused on the entire “life cycle” of equipment–from design to operations and maintenance, and then restoration or decommissioning. The breakthrough in our thinking came when we began to truly understand the “Pillars of TPM” and how they worked together and focused on results, not merely on activities “in the hopes of improving performance.” Here are the five basic Pillars of TPM:
- Improving equipment effectiveness by targeting the major losses
- Involving operators in the maintenance of their equipment
- Improving maintenance efficiency and effectiveness
- Training to improve skills and knowledge
- Early equipment management and maintenance prevention design
ISO 55000 and asset-management systems
The five Pillars of TPM also formed the basis for an easy-to-understand “asset-management system” that pre-dated PAS 55 Asset Management Specification by more than 20 years, and ISO 5000 by more than 30 years. Understanding and deploying TPM as originally intended can establish a solid foundation for ISO 55000 on the plant floor and help establish an “asset management mindset” at the top management levels of the organization. Let’s explore.
The ISO 55000 (55001) Asset Management Standard released in February outlines the requirements for an “asset-management system” (a system for managing an asset-management system). The new Standard, however, does not prescribe how to establish such a “system,” nor does it prescribe how to manage assets. At the heart of the ISO 55001 Asset Management Standard are requirements for the appropriate stakeholders to address the “at risk” assets throughout the entire asset life cycle while providing a “line of sight” from the asset-management actions to the goals and objectives of the business. Sounds pretty academic.
Here’s where TPM comes into play: It not only defines what an asset-management system is, it outlines HOW TO establish an asset-management system based upon the five TPM Pillars.
I am convinced, especially after teaching about and consulting in TPM since the early 1990s and conducting PAS 55 gap analyses since 2012, that starting true TPM can set the stage for launching an ISO 55000 mindset in an organization. I also believe that the converse is true: If you cannot successfully deploy TPM in an organization, the road to ISO 55000 certification will result in dead ends.
TPM’s most important pillar
Our step-by-step exploration of TPM as a systematic approach to asset management begins with an examination of its first and most important Pillar: “Improving equipment effectiveness by targeting the major losses.” Keep in mind that all five Pillars were designed to work together rather than stand alone–to be “interdependent” rather than independent. (The remaining TPM Pillars will be covered in future “Uptime” columns.]
Improving equipment effectiveness by targeting the major losses: The first Pillar of TPM serves two essential purposes: 1) What to focus on; and 2) how to measure progress. While the purpose of this Pillar is to “improve equipment effectiveness,” three key words in it are what make that happen: “targeting” and “major losses.”
Identifying and addressing the “major losses” provides a basis for the compelling business case for improving equipment effectiveness–the foundation for work-culture change. Major losses are just that: The equipment-related losses that have a large impact on equipment effectiveness and on the business.
Major equipment-related losses in a production process can be associated with the actual production-line equipment, other equipment in the product/process flow, utilities (i.e., electric, compressed air, water, steam, gas, etc.), and material-handling equipment. To narrow down the specific equipment focus, it’s important to first analyze the overall process flow. Start by looking for interruptions in the planned production flow rate (per hour, per shift) and the impacts on the business.
For example, let’s consider the major losses relating to a material-handling forklift compared to the single-point-of-failure machines in a production process. The forklift can stop production because materials cannot be moved to and from the production process. Chances are several other forklifts could be called into service within a short amount of time to remedy the production losses (a low-cost work-around).
But when a single-point-of-failure machine fails, there is no work-around—and production comes to a halt until the machine is repaired. The costs of parts, labor, production losses and safety incidents are significant unplanned business expenses that add to the cost-per-unit produced.
In reality, a TPM case can be made for addressing both the forklift and the single-point-of-failure machine based on the frequency and duration of the failures. The business goals, however, are more at risk when the single-point-of-failure machine in a production process fails than when a dedicated forklift fails. Accordingly, an asset-management strategy for the single-point-of-failure machine should be more robust than that of the forklift.
The plant-floor perspective of TPM
Now let’s view TPM deployment from a pragmatic, plant-floor perspective continuing with the same TPM Pillar, “Improving equipment effectiveness by targeting the major losses.”
There are three plant-floor concepts at work here: Reliability, Root Cause Analysis and Constraints (or bottlenecks).
Reliability & Root Cause: A TPM strategy uses the concepts of Reliability and Root Cause Analysis for targeting the major losses related to the single-point-of-failure machine in a production process (let’s call this Machine Z) to the point of identifying and eliminating the causes. Before we wander too far from Machine Z’s losses, we must remember what a “failure” is. If the machine does what it is intended to do in defined operating conditions for a stated period of time, it is considered reliable. If the machine ceases to do what it is intended to do, it has “failed.” All failures are not catastrophic breakdowns. A “slow-down” can be a failure too.
Constraints: Any production process flow has a constraint–an integral part of the process that sets the pace for the entire process. For example, if Machine Z, being a single point of failure in a production process, is operating at 90% of its intended cycle time, it has failed because it slows the entire production process down to its speed. Even at 90% cycle time, it has a negative business impact (i.e., interruptions to downstream flow, late product deliveries and higher cost-per-unit produced to name a few).
In this example, Machine Z becomes our TPM focus. Having determined this focus, the next step in “improving equipment effectiveness” is to group Machine Z’s “major losses” in three primary data categories. The three primary equipment-effectiveness loss categories in TPM include:
• Availability Losses: Planned downtime and unplanned downtime
• Performance Rate Losses: Speed and cycle time
• Quality (Yield) Losses: Defects, rework, scrap
“Overall Equipment Effectiveness” (OEE) is often treated as a metric that factors the three loss categories (above) expressed as percentages: Availability, Performance Rate and Quality/Yield. This is where the calculated confusion comes in. Contrary to popular belief, OEE percentages are not meaningful data, and 85% OEE is not “world class.” OEE percentages do not provide the quantity, duration or nature (reasons) for the losses.
Categorizing data in ways that recordsthe quantity, duration and nature (reasons) for specific types of losses is essential to achieving rapid and sustainable bottom-line business results from TPM. Frequently, the lack of good data is the weakest link in process-reliability improvement (i.e., not having the data to turn into meaningful information and then into prioritized action items).
Focused improvement in TPM depends on having accurate and reliable data to identify the “major losses” and then to prioritize focused improvement actions. Having this accurate and reliable data as an equipment base line also serves as a way to measure progress (i.e., “Are our TPM actions making improvements in availability, performance rate or quality and yield?”).
TPM as an asset-management system
The ISO 55000 Asset Management Standard requires that a system be established to assure consistent, accurate, and reliable practices that address the at-risk assets (equipment in this case). The principles of TPM prescribe the same.
In applying the ISO 55000 requirement to the first TPM Pillar (“Improving equipment effectiveness by targeting the major losses”) there needs to be a documented, systematic and audited way to collect, analyze, trend and report all of the data used to prevent (or eliminate) the major losses of the most at-risk equipment. In the absence of this type of data-management system, neither TPM nor ISO 55000 Asset Management will be successful.
Future installments of this column will expand asset-management concepts to the remaining Pillars of TPM, and, possibly, OEE.