Lean Is Cool

Air conditioner producer Trane, a unit of Ingersoll Rand, drives lean manufacturing principles deep into its operations, touching every process, every pair of eyes and every pair of hands on the manufacturing floor. The company says that, on average, a Trane air conditioning unit is installed every minute of every day. And, transporting manufacturing components and parts to the right workstation at the right time has driven the company to find customized material handling aids to keep the air conditioner production line flowing like cool air on a hot day.

“We are using lean projects to tighten up and take advantage of efficiencies in our manufacturing operations,” explains Bruce Pate, an industrial engineer in Trane's largest facility in Tyler, Texas. The Tyler plant for Trane Residential Systems employs 2,000 people and manufactures condensing units for air conditioners.

Pate says he and his colleagues have put material handling on the manufacturing floor under the microscope. “We knew we could improve the flow of materials in our manufacturing process, so we pulled together a lean event to dig into the issues,” he says.

During their continuous improvement (kaizen) events, the cross-functional teams of salaried and hourly employees attacked the problem by identifying ways of saving floor space, combining jobs and streamlining the movement of components and parts. Pate says his teams continually identify ways to smooth out inefficiencies in the plant's five assembly lines that sometimes experience material shortages and interruptions.

“We've created a central supermarket of components and parts, with a highly efficient ordering and replenishment system,” Pate notes. “We figured out that, with a components supermarket, we could save time, avoid delays and transport exactly the right pieces to the right line at exactly the right time.”

And, that's no small feat for a facility churning out 5,000 air conditioning units per day.

Ergonomically Correct

The Trane lean teams also faced another task — how to get those thousands of types and lengths of tubing, suction discharges, parts and components to each manufacturing station.

Fortunately, Trane managers anticipated the challenge and invited material handling experts from two firms to participate in a lean event to assist with design and implementation of the cart needed to transport materials on the manufacturing floor in Tyler. One of them was Ryan Metzdorf from material handling equipment manufacturer Valley Craft. The fact that Metzdorf was invited to the lean event exemplifies Trane's partnership approach with its suppliers.

“Our team evaluated the unique needs of each line, including ergonomic assessment and load requirements,” Pate points out. “When we got through, we had a concept for a customized cart that could carry enough product to the lines that would keep them supplied in an ergonomically correct method and in a timely manner.”

Valley Craft was chosen to manufacture the carts, through its Ovation custom manufacturing service. Trane requirements were conveyed to the Ovation team in Minnesota, which produced conceptual sketches and 3-D images of the proposed carts. Interaction between the Trane and Ovation teams led to prototypes that were studied and fine tuned, and finally to production of the carts using Ovation's own lean manufacturing process.