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A tale of TPM

What do you do when increased customer demand conflicts with maintenance needs? Spacesaver Corporation turned to total productive maintenance.

“It’s fine to celebrate success, but it is more important to heed the lessons of failure. How a company deals with adversity suggests how well it will bring out the best ideas and talents of its people and how effectively it will respond to change.”
— Bill Gates, Microsoft

“Failure is only the opportunity to begin again more intelligently.”
— Henry Ford, Ford Motor Co.

“Remember, Charlie Brown, you learn more from your defeats than your victories.”
— Lucy Van Pelt, Peanuts comic strip

The day the line died
The pathway to success isn’t always the smoothest. Gates dropped out of Harvard. Ford’s first car company, Detroit Automobile, went belly up in two years. Lucy struggled mightily as a rightfielder.

Spacesaver Corporation hit its pothole in 2001. But the Fort Atkinson, Wisconsin-based maker of high-density mobile storage systems used the lesson to eventually find plant-floor success.

Spacesaver’s productivity parable centers on Line 5, located in the fabrication area of the 270,000-square-foot facility.

“Line 5 produces all of the shelf supports for our plant. It’s crucial to our business,” says vice president of operations Jim Muth.

The numbers don’t lie. The plant makes more than 6,000 shelves per day. Each shelf requires two supports for the assembly process. Do the math and Line 5 must produce in excess of 12,000 supports each day.

The line had difficulties meeting the demand. It ran nights and weekends to keep the parts flowing downstream. And then one day, in June 2001, Line 5 flatlined.

“The crash hit us right between the eyes,” says Muth.

According to fabrication superintendent Marty Weber, air pressure issues, oil leaks, a cracked ram shaft, a non-level ram and air cylinder wear and tear contributed to the crash of the line’s main press. Looking deeper, the existing production/maintenance philosophy left the line vulnerable to such damage.

“We were in a ‘run it until it dies’ mode, and it died,” says Weber. “Because of product demand, we neglected the equipment.”

The machinery stopped. Demand for shelf supports, however, did not.

“Line 5 was down for several weeks,” says plant manager Michael Kling. “Just like that we had to find outside suppliers that (combined) could produce 12,000 shelf supports a day. It caused a substantial amount of pain to get back on schedule.”

In the aftermath, Spacesaver strongly considered tearing out the line’s 16-year-old machines and buying new equipment at a capital cost approaching $1 million.

“It would have been a major investment,” says Muth. “I didn’t want to start a culture where buying new was the answer, the fix-all, when the equipment got old.”

Following Henry Ford’s footsteps, Spacesaver turned the crash into an opportunity to begin again more intelligently.  The company found the smarter solution in a lean manufacturing technique called Total Productive Maintenance (TPM).

Solution was in front of us
Spacesaver was no stranger to lean concepts. In 1998, the company was acquired by KI (formerly Krueger International), a global furniture manufacturer with a lengthy lean history, headquartered in Green Bay, Wis. In 1999, Spacesaver adopted several lean principles and experimented with kaizen events. The next year, it initiated a plant-wide value-stream mapping project and completed 21 kaizen blitzes.

“The solution was right in front of us,” says Muth. “When we had the incident, the equipment on Line 5 was 16 years old. That’s not old. But at the same time, we did 8,000 to 12,000 pieces per day for 16 years. That’s more than 40 million parts. If we would have made the investment in new machines but treated it the way we did the current line, we would have been right back at this point. What drove us to TPM was its roots in lean.”

TPM is an integrated set of activities aimed at maximizing equipment effectiveness by involving everyone in all departments at all levels, typically through small-group activities. TPM usually entails implementing the 5-S system, measuring “the six big losses” (equipment downtime, adjustments, minor stoppages, unplanned breaks, time spent making reject product and waste), prioritizing problems and applying problem solving with the goal of achieving zero breakdowns.

Spacesaver sought advice from the Wisconsin Manufacturing Extension Partnership. The talks confirmed TPM as the appropriate solution.

“With TPM, we believed we could bring the equipment back to nearly like-new condition,” says Muth.

How TPM works
A TPM project typically uses a modified kaizen format and can span several months. It includes:

Training: The company selects a team of people, including machine operators, maintenance workers, supervisors and management. The process begins with a day of training, simulations and case studies, plus instruction on how to work in teams. The team also learns how to collect Overall Equipment Effectiveness data (see sidebar). OEE is shop floor-collectible data that documents how long a machine is actually running, how long it’s down, how many reworks are needed, and so on. OEE provides an easily applied and understandable way of measuring machine utilization. It also serves as a record over time of a machine’s performance and can be used as a reference guide for future troubleshooting.

The TPM team then decides which equipment to target first for improvement.

OEE data collection: During the next three weeks, the first OEE data is collected. This is done by operators on all shifts. This serves as baseline data for the project and shows where the problems lie.

OEE data analysis/problem prioritization: The team meets to analyze the data and prioritize the uncovered problems. The problems are categorized according to the “six big losses” that reduce a machine’s efficiency. From there, the root causes of these problems are targeted and corrected.

TPM implementation: Next, the team works to restore the equipment to make it as reliable and productive as possible. Using the OEE data, high-failure-rate areas are identified and the necessary repairs performed. Then, daily and periodic maintenance schedules are established. A 5-S organization and cleanup project is also part of the process.

To document progress and improvement, the team continues to collect and analyze OEE data from the equipment.

Bringing TPM to Line 5
The Line 5 TPM team consisted of team leader Weber, three Line 5 operators (one from each shift), one operator from outside the area, a maintenance mechanic, two engineers and a representative from purchasing.

“This project gave us the chance to take a step back and see how production and maintenance functioned and what the consequences were for our actions,” says mechanic and team member Bruce Campbell.

“From maintenance’s perspective, we had a real problem getting access to the line. Many times, we were asked to put a Band-Aid on a machine just to get it back up until the weekend. Then on Sunday, we could come in and do what we had to do to fix it right. However, if the production output on Line 5 was low, the operators would have to work on Saturday and Sunday. The fix then would be scheduled two weeks out. It wasn’t the right thing to do. But from the operators’ perspective, they needed the machine so they could get parts out.”

What is more important: parts production or equipment maintenance?  Spacesaver pondered that chicken-and-egg conundrum and decided that “both” was the correct choice.

Utilizing one of the tools of TPM, plant leaders reassigned a host of routine maintenance tasks to machine operators. In essence, operators were given joint custody of the equipment.

“Operators used to insinuate that maintenance couldn’t keep the machines up and running. Maintenance would insinuate that operators weren’t running the machines correctly,” says Weber. “Joint ownership helped put everyone on the same page.”

Adds Muth, “It’s now everyone’s job to ensure that this machine runs as efficient and productive as possible. The operator should have as much accountability and responsibility as maintenance does.”

Operators received training as well as a daily checklist of preventive maintenance tasks. The list includes checks for fluid levels, tool and die condition, and oil and air leaks, and examinations of pressure and thermal indicators. It also includes machine cleaning activities.

“They go through a running PM,” says Campbell. “The operator checks the machine out for certain issues. That person can address the minor issues. If anything larger in scope needs addressing, the supervisor generates a work order and we take care of it. This allows for more proactive work rather than waiting for someone to say, ‘It broke because it ran out of oil.’”

Maintenance relinquished some of its control in the area of asset health but, in doing so, found that its time and skills were better utilized.

“We didn’t have a problem handing off our knowledge to the operators,” says Campbell. “I can fill oil. I can do all of the small stuff. But with the knowledge and skills I bring, I’m better off focusing on bigger issues. We now can get into projects rather than firefighting.”

Examples of maintenance’s shift from reactive to proactive work includes expanded use of infrared analysis and other predictive tools, experiments into oil analysis and the creation of a “fourth shift” that handles advanced PM tasks on Saturdays, Sundays and Mondays.

A byproduct of the arrangement has been greater understanding and teamwork between the two groups.

“When TPM occurred and we increased our production numbers so drastically, it wasn’t as big of a deal for me to say, ‘I need the line for six hours in order to fix this the proper way,’” says Campbell. “There will always be capacity issues because we are a lean manufacturer and we don’t build the inventory up. However, we do have the capability to build things up so we can take the machine down for six hours.”

Getting results
The TPM project led to many action items for Line 5 outside of operator checklists and proactive maintenance. These include:

ACTION ITEM #1
Square and level the press.

Goals: Make certain the press ram operates level; eliminate undue wear to the slides and gibbs of the press; ensure part quality is consistent from start to finish; and, avoid stress cracks in the press frame.

Results: Spacesaver contracted an outside firm to level and square the press; during the firm’s visits, maintenance rewelded the stress cracks in the frame.

ACTION ITEM #2
Capture leaks.

Goals: Review the entire line for leaks around fittings, caps, cylinders, seals and tubes.

Results: Numerous tubes, pipes and fittings were replaced. Catch basins and drainage tubes were also installed to catch overspray of coolant and excess oil.

ACTION ITEM #3
Totally rebuild the air manifold system.

Goals: Eliminate all leaks; reduce the number of air controls by 50 percent; and, refurbish or upgrade the air cylinders to newer technology.

Results: The entire air system for tooling was refurbished to reduce the number of controls from 16 to eight. Also, the existing cylinders were reworked with new bushings that eliminated leaks. Finally, the controls were relocated to an area protected from the elements.

ACTION ITEM #4
Redesign the transfer conveyor between the press and the riveter.

Goals: Gain access to the back of the press for working on tooling; eliminate downtime due to problems with the transfer system; and, eliminate personnel standing on the conveyors in order to gain access to the top of the press.

Results: The conveyor and tooling was modified to easily swing out of the way. This provided greater access to the rear of the press for both maintenance on the tooling and the top of the press.

Easing the pain
Everyone faces adversity and tough decisions on the road to achievement. How you handle it determines your ultimate success.

After dropping out of Harvard, Bill Gates helped start a little company called Microsoft. After Detroit Automobile tanked, Henry Ford created the Ford Motor Company. And on April 21, 1994, after more than 40 comic-strip years of trying, Lucy Van Pelt caught a fly ball and gave Charlie Brown’s hard-luck baseball team a victory.

“We had to have the pain before we saw things clearly,” says Muth. “It just so happened that our pain hit us during the busiest part of our business and in one of the most critical areas of the plant.”

Spacesaver handled the pain on Line 5.

“Because of our work, I’d say 30 to 40 percent of downtime has been eliminated,” says Weber. “Overtime is under control. If we do work a Saturday or Sunday, it’s because of the workload, not because of an equipment breakdown.”

Recently, the company has spread TPM and other lean techniques to other areas of the plant. Such improvements were critical as business increased substantially.

“The business has grown 60 percent in recent years without adding brick and mortar. And, we still have room to grow,” says plant manager Kling.

A large-scale business jump and a more productive plant?  Now that’s turning peanuts into peanut butter.

This article appeared in the April/May 2005 issue of MRO Today magazine. Copyright, 2005.

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