Total Productive maintenance is helping material handlers keep their equipment healthy while it’s running, instead of waiting until it breaks.
Anyone following the U.S. healthcare debate may have noticed that medical professionals, while offering different solutions, seem to agree there’s a problem with the current system. Physicians and other healthcare experts point to ever-climbing costs of a system based on “reactive medicine.” For too long, they say, we’ve been fixing diseases rather than preventing them in the first place. They point to an aging population and the impending retirement of baby boomers as proof that a major shift in the way we think about medicine is long overdue.
They should take a page from the lean playbook. This shift in thinking, from reactive to preventative, is old news for lean organizations. Consider total productive maintenance (TPM), a lean strategy that focuses on eliminating costly downtime caused by reactive maintenance – fixing equipment after it breaks.
Seiichi Nakajima, an officer with the Institute of Plant Maintenance in Japan, is usually credited with developing and defining TPM, which has three main goals: zero breakdowns, zero defects and zero accidents.
More than Prevention
Andy Carlino, co-founder and partner at the Lean Learning Center, views TPM as healthcare for equipment. “It’s similar to doing regular self-examinations and monitoring your diet to maintain your health and prevent sickness before it happens,” he says.
But prevention is just one part of TPM. While preventative maintenance (PM) procedures coincide with planned equipment downtime, TPM occurs while equipment is operating. “The ‘productive’ in TPM means routine maintenance activities are performed while equipment is running, rather than waiting for planned or unplanned maintenance,” Carlino explains.
“These activities could involve oiling a chain, listening for motor noise or just making sure equipment is operating the way it’s supposed to.”
The “total” in TPM means all employees, not just maintenance workers, are responsible for equipment health, he adds. “With TPM, problems are detected earlier because of operator involvement. Operators notice small problems, which eventually become big problems if unchecked. With TPM, everyone is engaged in the healthcare system for equipment,” Carlino says. “Think of it as you, your spouse, your doctor and your dietician all being engaged in your health, rather than just the doctor.”
Carlino believes many organizations have a narrow view of TPM. “They see it as just another tool in the lean toolbox,” he says. “They don’t recognize TPM is a manifestation of lean thinking.” Carlino explains that TPM can help an operation eliminate many, if not all, of the Eight Wastes which, according to lean thinking, companies tend to have: excess inventory, overproduction, over-processing, defects, idle time / waiting, excessive transportation, unnecessay motion and unused employee knowledge.
“Lean means having systems in place to solve problems,” he says. “With TPM, an operation subscribes to problem solving as a principle of lean.”
Material handling operations, in both manufacturing and distribution settings, can begin to practice TPM with a few small steps. “Start from a stable environment by cleaning and inspecting equipment,” suggests Carlino. Then, create operator checklists and a tagging system. “Similar to an airline pilot performing pre-flight, in-flight and post-flight checklists, there are many activities an operator can perform before, while and after running equipment,” Carlino notes. “Operators don’t replace maintenance people, but they should understand how the equipment runs so they can identify potential problems.”
He describes how a tagging system could work: “A yellow tag means an operator identified a potential problem in need of repair, and management schedules maintenance. A red tag means maintenance must respond immediately to prevent safety-related problems or equipment breakdown.”
According to Carlino, TPM takes a comprehensive, total approach to maintenance. “Operators contribute their expertise in running the equipment, and maintenance contributes technical knowledge about repairing it. TPM encourages employee engagement. The traditional, us-against-them mindset is rejected. Everyone in the operation works collectively to maintain the health of the equipment.”
The Missing Piece
Michael J. Trainor, senior consultant at bearings manufacturer SKF Asset Management Services in the company’s service division, sees TPM a little differently. “Organizations have been doing classical TPM for years,” he says, “but they missed the reliability piece.”
Trainor believes TPM is more effective when it’s tied to reliability-centered maintenance (RCM). The overall equipment effectiveness of RCM, combined with the cultural changes of TPM, results in a hybrid approach that eliminates everything that is not necessary to achieve reliability, he says.
RCM is a structured process, orginally developed in the airline industry, to determine the equipment maintenance strategies required for a physical asset to ensure it fulfills its intended functions in its present operating context, Trainor explains. RCM supports the planned maintenance and autonomous maintenance pillars of TPM and therefore facilitates continuous improvement.
TPM alone can lead to over-maintaining equipment, says Trainor. “Traditional TPM relies on operator inspections and checks that may not be necessary if a more proactive approach is taken,” he says. “The hybrid approach incorporates preventitive and predictive maintenance to diagnose and determine exactly when action needs to be taken.”
“Up to 40 percent of manufacturing costs can be contributed to maintenance,” Trainor adds. “Downtime, breakdowns and repairs can cost three times as much and take three to five times longer than proactive maintenance procedures.”
Here again, the healthcare analogy seems appropriate. Preventing disease through simple lifestyle changes is much less expensive than treating the body once it’s broken. How much money could be saved if all material handling industries embraced TPM?
From Material Handling Management magazine, October 2009. Mary Aichlmayr