Continuous Flow Manufacturing: A Model Of Success

Everyone knows that the past several years have been particularly difficult for those in manufacturing. At Signicast Corporation (Hartford, Wisconsin), the industry leader in investment casting, the workforce in some production areas previously staffed by 30 operators, has shrunk to under half a dozen employees. At first glance, it might appear that the company, like many of its peers, reduced its workforce to get through difficult times. Nothing could be further from the truth.

Founded in 1959, Signicast has accrued more than 40 years of experience in the production of investment castings. The company built its first new plant in Milwaukee, Wisconsin, in 1972. After 20 years of growth and expansion, Signicast decided to open a second facility in the nearby city of Hartford.

The investment casting industry had long been faced with the reputation of being costly and time-consuming. When designing the new location, Signicast decided to meet these challenges head-on.

In the early 1990s, a desire for lean production led to the development of continuous flow manufacturing. This concept quickly became the centerpiece of Signicast's Hartford facility.

The initial production area, now known as Module 1, went into full-time, 24/7 operation in 1993. The facility incorporated a level of automation that was rare at the time.

"Our company is the embodiment of thinking outside the box," explains Jim Okonek, Signicast's toolroom and machining manager. "We don't want to do anything just like anyone else, because we know there's always a better way."

Indeed, nearly every aspect of Signicast's operation points to a specific vision. An automatic storage/retrieval system delivers needed materials to workstations. A central information system guides this process, automatically downloads detailed job data to the needed machines and constantly monitors job progress. The end result is a system that can provide smaller lots of parts in a fraction of the time required by competitors. Additionally, by eliminating material handling and reducing direct labor expenses Signicast can provide parts at a very competitive cost.

Confident in its ability to find the best way of performing an operation, Signicast constantly looked for areas of production that could be brought in-house.

"There's a huge cost associated with sending a part from one vendor to another to another," say Mr. Okonek. "Our goal is to be able to do anything a customer needs on a part."

The first step in investment casting involves producing an injection die used to form wax patterns that, in turn, are used to create ceramic molds. Throughout most of the 1990s, Signicast outsourced most of the machining of this tooling. In 1999, the company purchased two machining centers from Mori Seiki (Rolling Meadows, Illinois), an SH-500/40 horizontal and SV-500/40 vertical, for use in the toolroom.

"We went from a tool a month to five a week," recalls Mr. Okonek. "We used to do one tenth of our tooling; now, we have it all in-house, just by adding two Mori machines."

Rapid growth necessitated the addition of a second module for casting in 1997. By 2000, success in the machining of tooling led into the development of a new module dedicated to the machining and finishing of parts. Experience dictated the inclusion of Mori Seiki machines in the new module.

"With continuous flow manufacturing, we cannot afford to be down at all," explains Mr. Okonek.

During the past decade, Signicast has become accustomed to growing at a faster than forecasted rate. Its machining operations are no exception. The area allocated to machining will soon be doubled to accommodate the increased workload. The company currently owns eight Mori Seiki machines, including three ZT2500Y turning centers and the most recent addition, a NH5000 horizontal machining center. The machines provide a perfect fit for Signicast's lean philosophy.

"With our setup, we bank on eliminating half of the direct labor on a part and like to have it down around30 percent," says Mr. Okonek. "It's now possible to take a lot of jobs that used to require four or five operations and turn them into one-operation jobs. The more a machine can do with the doors closed, the more direct labor you're taking out of a part. Mori really helps us with that."

All of this results in cost and time savings that translate into increased business. Signicast's annual sales have grown more than ten percent each of the last 3 years, breaking the $100 million mark in 2004. A list of current customers reaches into the hundreds and includes Harley-Davidson, Stanley Bostitch, Emerson and Caterpillar.

While the company's constant efforts towards automation have reduced the labor needed per part, business has grown so rapidly that no lay-offs have been required and, in fact, Signicast has been regularly hiring new workers throughout the whole of the past decade.

"We look at the best way to do a part and then find the least expensive way to do that. When you send a part overseas, it takes time and you have all kinds of quality problems that might not show up until a couple of years down the road. We can take a part from development to delivery before it would even be started overseas—and at a competitive price," explains Mr. Okonek.

As the economy continues to recover, it is important that manufacturers look to companies like Signicast that have not only weathered the storm, but have also grown throughout its worst. Only by fully using technology to find new and better ways of doing things will companies shrug off the threat of foreign competition and find success in both good and bad times.