Five steps into the wax injection room in Signicast’s Hartford, Wis., Module 4, it’s easy to assume it’s break time for the investment caster’s workers. Walkways are clear, and stations are empty but for a single employee drifting through.
Then you notice the robots. Quietly but efficiently they work in their cells, extracting freshly produced wax patterns from the injection machines and transferring them to cooling baths.

Among four robotic cells, a single Signicast employee makes her rounds, welding the wax patterns onto an investment tree before hanging them in the automated storage/retrieval system, which transports the trees through the remaining operations. It will be the only part of the investment casting process—from wax injection to finishing—that is performed manually.

The scene is similar in the dipping room, melt department and finishing area. Robots are merrily at work while the humans are kept busy tweaking the operations here and there to keep them running smoothly. Together, they make possible Signicast’s continuous flow production, which the firm has improved upon in stages as it expands.

Module 4, the most recent expansion completed at the start of 2007, is the company’s fourth investment casting facility created at its Hartford campus. The new facility incorporated the automation advancements present in Signicast’s existing facilities, such as autopouring, robotic semiautomatic presses and automated finishing cells, while improving upon the melt area and finishing cells. Module 4 also brought stainless steel to the mix of low alloy and tool steels, adjusting the automation to work with all materials.

A part moves through production in Signicast in days, not weeks. The average time for a product launch from tooling order to production has been cut to 9.3 weeks, inching its way to the firm’s eight-week goal. As a result, the new facility has been met with continued product growth and prospective customer interest. Last year, Signicast, which was acquired in July by private investment firm The Pritzker Group, Chicago, saw $130 million in sales and earned 27 new customers, compared to the typical gain of 15 a year. It’s on pace to bring in 27 or more customers in 2008 and $140 million in sales. These efforts have earned it the title of MODERN CASTING’s 2008 Metalcaster of the Year.

Time for a Revolution

Signicast President Terry Lutz has overseen expansions at the company’s original Milwaukee facility, as well as the construction of the Hartford complex, module by module. When the facility in Milwaukee grew as much as land allowed and it was decided to build a new facility at a different site, he saw an opportunity to be revolutionary. Everything that could be automated was—even material handling. Castings are no longer kept in inventory but shipped straight from the end of the line as needed, which often means daily shipments to the customer. Gone are the rogue bins of castings pushed aside to address another part on the schedule. Schedules are obsolete.

“It started with us looking at the Milwaukee facility and seeing a bunch of people hunting around for the parts they were supposed to be working on,” Lutz said. “Now we start and finish an order before moving on to the next one.”

Employment schedules were shaken up as well. Five- and six-day work weeks were eliminated. The new shift schedule, which covers 24/7 operation, features four shifts that rotate three and four 12-hour days a week. Each employee was given access to all the information they might want—on the part or the company. Computers at each station show employees the information they need to make production decisions, solving problems before they become bigger problems.

And lean manufacturing has been taken as strictly as possible. This means even the tooling department operates at all times in continuous flow.

“Module 1 and 2 [at Hartford] was a great leap in technology and automation from the [Milwaukee] facility,” Lutz said. “It really was a technological breakthrough for the industry, and we’re still waiting and hoping for everyone to catch up.”

Meanwhile, Signicast continues to look ahead. It completed a machining and secondary operations module (Module 5) in 2001. Parts made in the investment casting modules are transported via overhead conveyor to Module 5 for finishing operations, including full machining, painting and assembly. Its Module 3 investment casting facility was finished in 2003. Module 4 is the latest extension meant to handle the influx of growth.

“So far we’ve put in 75% of the equipment we’re going to need, and we’ll work up to 100%,” said Todd McDonald, vice president of sales. “We try to minimize the equipment to just what we need at that time.”

Module 4 was designed to diversify Signicast’s just-in-time offerings by incorporating stainless steel in the same line as the tool and low alloy steels. But adding stainless steel had its challenges. With the other steel alloys, Signicast had devised a cryogenic break-off system that removed castings from investment trees through freezing, but this was not possible with stainless steel. Instead, those castings are diverted to a rugged robotic cutting wheel for cut-off.

In the melting and pouring department, robotic pouring and a new method for protecting the molds after pouring was needed. Test bars are now required for some of the stainless alloys, as well.

The addition of stainless steel was just one change from Module 3, which Module 4 was modeled after.

“After each module, we really look at how and why we are doing certain things and what can be improved,” McDonald said. “For instance, we always had the melt floor sunk down, which facilitated manual pouring. In Module 4, we kept the pouring station on the ground floor because of automated pouring.”

Pouring in Modules 3 and 4 is conducted with two robots, one to pick the mold from the burn-out oven and the other to pour the metal, and a turntable that covers the newly-poured trees and rotates them to a cooling line. According to Lutz, the automated pouring was one of the most challenging innovations at Signicast but now has improved the consistency and speed of the melt department and removed a stressful, manual job.

“We spent well over a year developing the system,” Lutz said. “We tried it out with water first, and it worked fine. But when we switched over to metal, we realized we had entered a whole new ballgame.”

The Signicast brain trust had to figure out how to handle the fragile investment shell before and after pouring while syncing the two robots to work together for the most efficient approach. 

“It took a year of development and then six months to operate half-way decently and another six months to be good at it,” Lutz said.

In March, Signicast also began a new venture in making its own wax. When wax had been delivered from an outside source, it had already been heated and then cooled for transport. Before the wax could be used in the shop, it needed to reheated to molten temperature. To further streamline its operating time, Signicast decided to make its own wax so it could be pumped directly to the wax injection machines without solidifying and re-liquefying. The wax is pumped hot to the machine and cooled to a paste before it is extruded into the die at 115F (46C).

In Flex

Signicast staff is already sketching out operational improvements for the next facility.

“We look for what our customers want, and the rest is self analysis,” Lutz said. “How can we make a better quality part? How can we reduce the number of man-hours? How grueling is the work? How boring is it? A boring job drives employees nuts.”

The vision for the next expansion is flexible automation, breaking free of the current guidelines parts must meet in order to work in the continuous flow model.

“We’ve been good at automating, but we have had to standardize,” Lutz said. “We’re looking to broaden that.”

Some of the development work for flexible automation is underway at Signicast’s Milwuakee facility. While the Hartford complex is a showcase of technological advancement, the Milwaukee plant also serves an important purpose.

“[Milwaukee] can handle everything that [Hartford] cannot,” Schuemann said. “It has a lot of the same technology as Hartford, only on more flexible terms.”

Proving its worth, the Milwaukee facility produces all the castings for Signicast’s second largest customer. 

“The technology there is really good, and the plant is responsive and runs well,” Lutz said. “There will always be a place for the Milwaukee plant.”

What Recession?

Signicast’s sixth facility is roughly scheduled for construction in two years, depending on how the economy affects production.

“Historically, we’ve gone into a recession later and come out quicker than the rest of the economy,” McDonald said. “Some customers are feeling the pains of the economy; others aren’t. Even in an industry that’s down, not everyone in the industry is down. That’s the benefit of a broad mix of customers.”

Industry growth in oil field, chemical processing and fluid technology has kept Signicast feeling positive about its position. According to McDonald, any industry that is exporting remains a strong customer for them.

The increase of new customers the last two years has helped, as well. For the last two or three years, the sales and marketing staff has been escalating its efforts to introduce more end-users to Signicast.

“Everywhere we go, we were educating buyers about what the capabilities of our investment casting process are,” McDonald said. “But there are still misperceptions that the process has long lead-times and is labor intensive and costly.”
Signicast’s sales staff seeks customers who understand the total cost of business and are planning for five years down the road.

“We tend to go after and attract the better-run businesses,” said Bob Schuemann, executive vice president. “The customers we’re dealing with, lean is their mantra. So we’ve made it our mantra too.”

New customers come mainly from conversions, although Signicast also is gaining some market share. Schuemann pointed out that true growth comes from its 350 existing customers, as first time customers will start by assigning only one job to Signicast. However, he said that typically, those customers will begin sending additional jobs Signicast’s way. Those new customers are the foundation for the company’s growth a couple of years down the road.

Signicast’s sixth investment casting facility is being planned to accommodate the new wave of customers from 2007 and 2008 that mature into multiple job contractors. The company feels it has a responsibility to ensure capacity is available for its customers. Currently, room for $40 million worth of new jobs is still available. This is by design.

“Customers now are very interested in making sure you do have the capacity,” Schuemann said. “A lot of our customers source 90 to 100% of their jobs to us, so we have to have the capacity for them. They have total flexibility with us; we really deliver true just-in-time parts.”