Putting out fires, the lean way

Figure 1 Crimson Fire managers have transformed the build-to-order shop floor from a traditional batch operation to one based on lean manufacturing.

Randon Bernards needs to fill jobs, fast. The fabrication technical lead at Crimson Fire has spent more time interviewing people during the past few months than he has since he arrived on the job six years ago. The shop enjoyed a dramatic uptick in orders in December, a time when most shops' work was slowing significantly.

"We wish we could take all the credit for [the surge in orders], but we can't," said Kevin Crump, president of the Brandon, S.D., firm, explaining that some significant National Fire Protection Association (NFPA) standards went into effect for trucks ordered in January 2009. Those require­ments include onboard safety systems that add thousands to the cost of the truck. So in December municipalities placed orders under the wire, before the NFPA standard went into effect. That saved Crimson's customers a chunk of change, but it also gave the fire truck OEM a record backlog of 225 trucks.

"I'm working so much, it's not even funny," Bernards said. The company had 99 truck orders in December alone. "Typically, we build 20 to 25 trucks a month. From December, we've got months of work there on top of the work load we already have."

So job interviews continue as the company works to fill about 30 vacancies across various divisions. Currently the fabrication department (which includes cutting and bending, but not welding) has seven working the day shift, six at night. The weld shop has about 15 workers skilled in wire processes for the trucks' tubular frames, and the assembly shop employs four people who gas tungsten arc weld (GTAW) cosmetically important components. Altogether, the company employs 275.

Crimson managers know how rare job interviews are today. In a twist of fate, Bernards' former employer, a nearby contract fabricator, shuttered five years ago after the last downturn. Unemployment even in sparsely populated South Dakota is rising, and Bernards admitted he has no trouble finding qualified people.

But the fire truck business isn't recessionproof, sources said. It just follows a different cycle. Unlike other budgetary areas in government, a city's capital spending budget usually lags declines in tax collections by about 15 months, so Crimson managers expect to feel the pinch once new, and most likely smaller, budgets are finalized. By then many players in the fire truck market will be vying for less business.

"This industry has more capacity than demand for products," Crump said. "About 5,000 units are sold each year, and there are about 62 manufacturers competing for those 5,000 units. It is difficult to distinguish yourself, because at the end of the day, a truck is a truck is a truck."

What differentiates a company is the fit and finish it can offer on a truck, as well as product innovation. "Years ago a firehouse might have four or five pieces of apparatus that had specialized uses," Crump said. "Now we're seeing a greater demand for multipurpose vehicles that carry everything one might need when responding to a call."

Managers are following industry demand and making sure the work is there to keep all their new hires on for the long term. The company has, among other things, expanded its product offerings with safe and ergonomic designs, and soon plans to launch a lower-price-point product line catered to frugal buyers. And over the past six years, the company has transformed its build-to-order (BTO) manufacturing floor to a tight, lean operation.

No More Part Piles

"We cater to the customer, and it's not always easy," Bernards explained. "No two trucks are the same."

The company builds trucks with a few-hundred-gallon water tank, 1,200-gal. tanker trucks, and everything in between. For many of them, the ladder may be placed in different areas of the truck, and they may be secured in various ways. The pump assembly may be built to different specs. The list of options goes on, and Crimson's manufacturing must account for all of them.

"In essence we're a job shop," said Crump, who rose through the ranks from manufacturing positions at Crimson and other fire apparatus and bus OEMs. "We tout the fact that for the most part [customers] can have it their way." The later the customer makes changes, the more it costs them, "but for them, that's an acceptable trade-off to get the product they want. And you thrive [in this environment] by going by lean manufacturing principles and following the mass-customization toolbox that comes with them."

Earlier this decade that toolbox was nonexistent. "When I started, we had 25 to 30 trucks in process at one time," Bernards recalled. "Parts were everywhere. We would build components for the next two months' worth of trucks. And we'd have a wall of parts."

Sure, the shop saved a bit of setup time by running large batches of common parts at once, but the cost of work-in-process, material handling, and inventory outweighed that benefit. The shop floor was swimming in work orders, all hinging on an MRP system that looked far into the future.

Since, the shop works via demand-pull, lean manufacturing (see Figure 1). Actual demand pulls work through the floor. The horizon has shrunk from months to about three to five days. The fabrication and assembly departments work on only about four trucks at a time, and batch processing has gone the way of the dodo. "We're now very much centered on single-piece part flow," Crump said. "What we build today, we consume tomorrow, and today we're getting to the point where what we build today we consume today."

"We've changed the way we build the body," Bernards added. "We only work with a limited number of trucks every few days (see Figure 2). We move the trucks through and make sure the manufacturing process is completed before starting another one, rather than having a whole mess of trucks being made at one time."

Crimson exploits modularity. Trucks can be built to suit, but about 80 percent of the truck comes from standard parts. Crump uses a LEGO® analogy: The truck can be made myriad ways, but the building blocks are the same.

The trucks have several standard chassis that come from Crimson's corporate parent, Spartan Motors, which in 1997 acquired Crimson (then called Luverne Fire Apparatus and Quality Manufacturing). The trucks' water pump components are outsourced, and Crimson assembles fittings to suit a customer's pump flow requirements. Around these parts, Crimson builds the truck body using modular parts that include tubular structures, doors, and ladder sections.

Part designs make strides toward errorproofing the shop floor. For instance, in many cases a left-side part has one that mirrors it on the right side.

"We try to attain the smallest bill of materials possible," Crump explained. "We try to reduce part count as well as part number count. To the greatest degree we can, we design 'left-right common' into the part so I can use it on the left side or the right side [of the truck]." This in effect designs-out potential assembly errors.

Lean, From the Ground Up

A customer order puts everything into motion, beginning with a "precon," or a preconditional design in which the customer determines all the desired components before the manufacturing process begins. Once the design moves to the floor, aluminum tubular sections are cut on the company's band saw with a feeding system and control that can store up to 200 programs.

The panels and compartment dividers, which fit within the tubular frame, are manufactured with the fabrication department's press brake, shear, and Jet Edge waterjet system, a 50-HP, 60,000-PSI machine that runs between 60 and 80 hours a week. The waterjet cuts about three-quarters of the components that go on the truck (see Figure 3).

Judging by the high volumes this shop's now producing (at least for the fire truck OEM world), why isn't a laser on the floor? "It's about setup time," said Bernards, who previously spent years as a laser programmer. Aluminum and stainless abound, and because lot sizes are small, operators must switch between the two often, which can add setup time on laser systems. "But with the waterjet, there is no setup time. Whatever you put in front of it, it will cut. We do a lot of plastic, and we do some regular carbon and irregular hot roll, but about three-quarters of what we do here is out of aluminum and stainless—the two highest-price materials you can buy on the market today," he quipped.

Parts are nested and produced for about four trucks at a time, then dropped in kanban bins labeled for specific trucks. The bins are then sent over to the welding and assembly area, where welders perform wire as well as gas tungsten arc processes (see Figure 4 and Figure 5). Often production is just-in-time to the point where parts literally are handed off to be assembled right away.

Midway through the customer has the option to inspect the truck in-process and can request (for an extra fee, of course) alterations to suit. The truck's modular design helps. Say a customer needs a generator cover design that's fire department-specific. Bernards goes to his CAD workstation, produces a new part, based on those modular building blocks and adding custom elements if needed, and then sends the part blanks to the waterjet and other fabricating equipment. After this the truck heads to the paint area, where the shop found further efficiencies with a new booth that shaved about 20 minutes off the paint cycle.

New School

Bernards recalled the greatest challenge in the lean transformation: a change in mindset. Having parts in inventory made sense, because managers could be sure they wouldn't be caught without the necessary items for body assembly.

"It was the old-school versus new-school way of doing things," he said. "We had some consultants come in and changed the mindset of our supervisors. We needed to focus on a week at a time, and everything else will fall into place. And we've actually done that."