Lean for Job Shops
Portuguese translation by Diogo Kosaka.
Despite their origins in high-volume production, lean manufacturing concepts can also help job shops
Mike Wriglesworth of W.W. Metal Fab, in Milwaukie, Oregon-USA, is a convert. His new religion is Lean Manufacturing.
At least, that is what he and his 85 employees have been practicing at work. With the encouragement and funding of one of its largest customers, truck maker Freightliner LLC, and support from the Oregon Manufacturing Extension Partnership (OMEP), W.W. Metal Fab is preparing to implement multiple lean initiatives.
The baptism took place last year when Charlie Martin, an OMEP consultant, visited W.W. Metal Fab and closely observed the shop floor, particularly the way the flame shield for the military truck was made.
The flame shield assembly is made of 10-gauge steel and sits between the truck's transmission and lift. Fabrication involved randomly bending several small brackets on a 14-foot press brake. W.W. Metal Fab's operators, according to Wriglesworth, would bend just enough of the small components until they had the right number to make one flame shield assembly.
In addition, the fabrication process called for the components to be marked with part numbers. This was done outside W.W. Metal Fab's bending operation and consumed a lot of process time.
“With that particular part we used to say ‘Ugh!’ because we didn't want to do that part. It was our bane,” said Wriglesworth .
Martin and the W.W. Metal Fab team looked at the process, drew how things flowed and redesigned the flow. The team suggested spending around 200 dollars on new tooling for the press brake to speed up part marking.
“We ended up putting the part marking into the setup and also revising the tooling on the press brake so that all the components in the kit were bent at once”, said Wriglesworth. And he added: “That way, the parts were moved onto a conveyor, and we had a spot welder behind the press brake operator. He would put the parts into a spot-welded assembly. We literally, had one-piece flow, one piece in and one piece out at a time”.
What used to take a week now takes just one shift to make. In addition, W.W. Metal Fab no longer has flame shield components piled up haphazardly all over the shop floor during the week, as was necessary in the past in order to complete an order.
Wriglesworth estimated that the company would achieve 30% labor savings once the changes were complete.
W.W. Metal Fab is not alone in finding the lean religion. Industry Week’s magazine conducted a census in 2003 that revealed that 36% of U.S. manufacturing companies consider lean manufacturing their primary improvement methodology.
But that picture likely included manufacturers that thought they were lean simply because they were forcing fewer employees to do more. George Koenigsacker, president of Lean Investments LLC and president of Hon Co., told Industry Week’s last year that he believed fewer than 5% of U.S. manufacturing companies were in fact “substantially lean”.
Gary Conner, head of Lean Enterprise Training and author of “Lean Manufacturing for the Small Shop”, believes the numbers are worse for metal job shops.
“I present (seminars) at shows like Westec and IMTS (International Manufacturing Technology Show) all the time. I am still amazed to run into people who haven't even heard the term”, said Conner. “I don't know where they've been living”.
That is a shame, because lean techniques can have a big impact on small to medium-sized shops, according to Brad Stump, manufacturing productivity director at Manufacturing Extension of Louisiana. Unlike the bureaucracy and barriers associated with large companies, small shops usually have managers who are also fabricators, better-trained employees and layouts that can be easily changed.
Stump adds that his experience comes from his observation. “Most of the people I've worked with are small family shops”, he said.
Origins of Lean
Most shops simply don't believe lean production applies to them. After all, the whole lean production philosophy emerged from the world of high-volume automobile production.
To be more precise, Taiichi Ohno, drawing on his experience and on Shigeo Shingo's ideas related to tool changeover and defect detection and correction, created the Toyota Production System, from which most lean manufacturing concepts derive.
Ohno joined Toyota young and worked his way up through various positions. As an assembly line manager, he began implementing his new method to improve the production process.
Taiichi Ohno really had no choice but to concentrate his efforts on process rather than technology. Because the American occupation forces in post- World War II Japan had imposed limits on the availability of credit, Japan suffered a collapse in car sales. Toyota was close to bankruptcy and could not afford new equipment, which many thought was necessary to improve production efficiency.
Based on the financial results, Ohno used intelligence instead of investment. The result is the Toyota Production System, which can be described by three main points:
- Make only what the market demands.
- Work in small lots.
- Create visual management in production to indicate where actions are needed.
Many tools used today to implement lean production were born from these principles.
This system propelled Toyota to become one of the largest carmakers and helped revolutionize the automotive industry worldwide. U.S. manufacturers and their suppliers are still trying to replicate Toyota's success today.
Not for me?
Of course, job shop readers are now shaking their heads in unison and thinking the same thing: “That's a nice story, but my operations are significantly different from an automotive plant. What does this method have to do with me?”
Vincent Bozzone, director of Delta Dynamics Inc. and author of “Speed to Market”, said he has encountered this way of thinking repeatedly.
“Here's what happens. If a job shop is looking to improve, and they think lean can help them, they'll go to a seminar that explains what lean is. What usually happens is that the people at the seminars are the ones who teach how to improve using lean techniques. They don't differentiate very well between lean in a mass production environment and lean in a job shop. They think their business applies everywhere”, he said.
“So the job shop owners are smart enough to understand that what the person is saying makes no sense at all, and they switch off the microphone”, Bozzone continued. “They don't take the next step, and when they do, they think it doesn't work. It's a matter of educating job shop owners and managers. If you want to become lean, you have to understand what that means in your work environment”, he stated.
For job shops, this means cutting waste. That is, waste in the ordering and delivery process that greatly increases lead time. It represents an extra step in the production process that raises cost. In other words, unnecessary production methods that put the quality of the final product at risk.
For job shops, lean does not apply to finished goods inventory. Unlike automakers and other companies that produce thousands of parts a day, job shops work to complete hundreds of different orders a day. It's made and shipped. That is also one of the key points to becoming lean.
“Matching supply with demand is already happening in some job shops. They already make to order. So the question is, how do you bring supply and demand close to each other? In this environment, the difference lies in time. If you want to bring supply and demand close to each other and the product is already exactly what was ordered, the only other variable is time”, the director concluded.
Fortunately, lean manufacturing principles, if applied correctly, can help job shops stop wasting time.
Becoming Lean
However, just as there are many different ways to fabricate and form metal, there are many ways to apply lean techniques in job shops. There are many opinions, and the tools are far more numerous. All successful implementations, however, share these traits:
- An outside point of view. Job shop owners would rather roll out the red carpet for an OSHA inspector than for a business consultant. If those same business owners are interested in learning how to make their operation lean, they should reconsider their opinions.
“I prefer to have an intuitive mind coming from the outside . I see this every day”, said Wriglesworth of W.W.Metal Fab.
“Sometimes, when you live it every day, you don't see the whole picture and you're limited to your own task”.
After the first success, Wriglesworth invited OMEP's Martin back to his facility to look at three other areas with potential for improvement.
Other manufacturers, on the other hand, did not need repeated visits. The ultimate goal is for someone to become the lean champion on the shop floor.
“What I do is educate people on how to think like a businessperson”, said Conner. “Most people on the shop floor grew up like I did. My father built bridges. I didn't get the chance to do an M.B.A. when I was younger. I went to work in shops”.
“So, from the standpoint of having someone from outside educate people about where to look, yes, I think there's great value in that. But in the end, they end up doing everything themselves. They are the experts”.
- Invest in training. Applying lean techniques in job shops requires more than just hanging a few colorful printouts on the board and occasionally asking workers what they think about something. It is necessary to set aside time to teach people to think critically about their individual efforts and about all processes.
Craig Reynolds, sales manager at Viking Tool & Gage Inc., Conneaut Lake, said 15 or 20 of the company's 120 workers regularly attended training sessions lasting two weeks. In the sessions, workers learned about the costs behind work and rework, plans to increase profits and the path needed to continue continuous improvement efforts on the shop floor.
“We try to help workers understand that there is global competition out there all the time. They need to keep improving. If they don't, someone else will and will take their jobs”, said Reynolds.
“This approach has helped us keep our work, and we've been able to pick up a lot of jobs from other plants. For one reason or another, they weren't competitive or were having problems in their processes”.
As an example, Reynolds pointed out that the stamping cells for extruded aluminum parts used to have three or four people loading material, unloading and packing parts. Now, thanks to the rearrangement of the equipment and of the worker's actions, the cells operate efficiently with just one person doing the work.
Training-related expenses can be minimized if they are a problem. There are grants available, or programs from local educational institutions. Greg Cornett, operations manager at Tennessee Stampings LLC, a supplier of metal fabrications to the automotive controls industry, formed a partnership with the University of Tennessee's Manufacturing Extension Program to establish a roadmap for implementing lean concepts. Eighteen months later, the company is well along in its implementation, achieving improvements such as a 30% reduction in redundant part handling.
- A “vision” of what is to be achieved. This can take various forms, but it is all about giving the troops something more than just marching orders.
For example, OMEP's Martin conducts hands-on simulations with job shops to show waste reduction and improvement opportunities in a fixture changeover scenario. The simulation can last from three hours to a full day.
Typically, after that, it's time for value stream mapping. This map details the process steps and indicates where there is value and where there is no added value. The paper document shows the course of the changes and the potential savings.
“The visual part of it is when you can take a breath and see the dollars that have been saved”, said Conner.
- Willingness to involve everyone. Lean principles apply not only to the shop floor, but also to the administrative area, that is, the office.
Think about the time needed to get a work order into a production schedule. Mike Wriglesworth suggests some ideas.
He is taking a close look at the information flow process. It now takes about five days to process an order, but he wants to bring it down to one day.
“I'm preparing us for growth. We have a lot more to offer, and we're busy with more activity with new customers right now. So I believe we're really going to expand next year, and I'm trying to get everything in order”, said Wriglesworth. “Office efficiency is something we struggle with a lot”.
- A commitment to avoid layoffs. Many workers in the United States have already experienced layoffs, plant closings and reduced contributions. Asking them to contribute to efforts that mean eliminating or restructuring their jobs sounds like asking them to dig their own graves. That is why it is important for management to commit that no one will lose their job during the implementation of lean principles.
Jim Poe, director of engineering at L.A. Darling Co., a manufacturer of metal store fixtures, shared this thought in an e-mail:
“the problem is that management often looks at lean as a way to increase capacity with fewer people. Factory workers figure this out very quickly, and so the impact lean could have is significantly reduced. We want people helping to make improvements, but if their friends start losing their jobs, continuous improvement quickly fades”.
- Invest in technology in a feasible way. The investment in some cases may be small, a few dollars for new tooling, or large, such as thousands of dollars for a new line of presses.
Investment in technology is not a prerequisite for implementing lean principles. While it can help in some circumstances, most improvements will result from productivity gains related to equipment setup or process restructuring.
“Our fathers and grandfathers could do business just because they had the machines. Nowadays that's not true”, said Conner.
Keep the Faith
Times are changing, and so is the approach to running a job shop. Lean manufacturing, adapted to the reality of job shop life, can help with the changes.
However, as in life, there are no guarantees. The experts interviewed for this article have seen failures in applying lean principles, but the main reason for the failures is a management disposition that allows internal sabotage. What is needed is an attentive person, looking down the path of meaningful change.
Therefore, it is up to management to lead the responsibility for change. If management remains skeptical, MEPoL’s Stump offers a suggestion:
“Talk to other people, to other companies that have already done lean. Talk to those who believe in it and to those involved in it”, he said. “There is something that is neither so expensive nor so painful to do”.
Live and do lean. Those who truly believe manage to do lean. What about you?
* Summarized from the original published on the LEI website (www.lean.org)
