The Fabricator - January 2016

As Abato explained, “We would get better re-
peatability, and there would be no custom tooling
requirements except for the end effector that holds
the parts.”
The medical field has plenty of applications for
small-diameter (many less than 0.5 in.) stainless
tubes, and some products actually require a portion
of that tube to be flexible. One end of the tube is solid
and rigid, with a few turned features, while the other
end has a thin web of material remaining, allowing
the structure to flex. Unlike the rigid section, it’s far
too flimsy to withstand the pressure from a hard tool.
And it’s all made out of one piece of tubing.

That part showcases a relatively new laser processing technology known as laser Swiss machining, which combines 6-axis Swiss machining and laser cutting. The machine looks like a standard Swiss turning center, with stationary and live tools, except that one of those live tools happens to be a low-powered fiber laser for cutting precise profiles on the tube OD (see Figure 5).

A Business System

Abato is no stranger to lean manufacturing. He graduated from Osaka University in Japan and spent years implementing continuous improvement projects. He arrived at Cadence three years ago, and when he and other managers with lean experience saw the current state of operations, they saw opportunity.

Cadence wouldn’t seem like a place where lean manufacturing could really apply, at least in the traditional sense. After all, the company produces thousands of different parts, and many of those parts pass through some truly advanced machinery, all tested to meet the stringent demands of ISO 13485 (the standard for medical device manufacturing) and customer requirements. When making a process or technology change, the medical device customer needs to certify that process.

Still, just because a process produces a quality product doesn’t mean it’s particularly efficient. For instance, until recently the company’s Rhode Island plant produced needle products using batch-and-queue techniques.

Admittedly, the waste from this process wasn’t
obvious. A fab shop processing large batches may
have a mountain of work-in-process between the
laser cutting and press brake department. But
when thousands of little parts fit into a box, as they
do with Cadence’s needle fabrication, all that WIP
doesn’t take up much space. A few boxes sitting on
the floor doesn’t look too wasteful.

Of course, those boxes of WIP sat for days between processes, waiting for certain machines to become available. This was something Abato and others picked up on immediately.

Managers would schedule an order to be cut. Then the entire batch would be moved to deburring, then grit blasting, then point grinding, then dimpling, and final assembly (each product consisted of a kit of two needles). In all, it took 25 days for the product to make its way through the shop.

The company did it this way because the operation produces a variety of different needle geometries. After all, the shop couldn’t possibly set up dedicated, product-specific lines.

Nevertheless, the improvement team uncovered what a lot of fab shops uncover as well. Although an operation may produce a lot of different part numbers, many of them undergo the same or similar process routing.

This happened to be the case at Cadence’s Rhode Island plant. The improvement team rearranged machines into a multiprocess cell, and now needles flow through the operation, from cutting to deburring to dimpling and so on, in a matter of minutes. “We used to have somewhere in the neighborhood of 170,000 pieces of WIP in that [needle] operation,” Abato said. “Now the cell produces 1,700 complete pieces a day with no more than 3,400 pieces of WIP.” The company also has implemented rhythm scheduling for some applications, grouping parts that require similar setups together. For instance, one grinding operation produces parts for a group of customers, each of which has a once-a-month delivery. Instead of sequencing these jobs strictly by the due date, the scheduler releases similar jobs together, so operators can avoid having to change out grinding wheels.

“So say we run 25 jobs for the month,” Abato said. “By the time you get to the 25th part, you may have changed your grinding wheel only once.”

The Whole Package Differentiator

All this is part of what the company is now calling
the “Cadence Business System.”
“It’s not a cookie-cutter approach,” Abato said.
“The Cadence Business System covers the entire
business at all six of our facilities, from corporate
headquarters to supply chain logistics to shipping
and receiving.”
If you visit Cadence’s home page, you’ll read about
a larger Wisconsin facility opening soon and details
about its advanced welding lab and finished-device
assembly (what it calls the Product Realization Cen-
ter™). It’s obvious that the contract manufacturer
is positioning itself as a supplier that can shepherd
projects from the early design stage through the
ramp-up to full production and final assembly.

But you have to do a little digging online to find out that the company has a proprietary grinding machine (along with a proprietary electropolishing process). These processes make the company competitive, for sure, but in the customers’ eyes, that technology by itself may not set the company apart from the competition. It’s instead the whole package: the sales and engineering collaboration in product development, the continuous improvement, and the technology mix (laser cutting, laser welding, stamping, machining, plastics manufacturing, assembly, and proprietary technology)—in other words, the entire Cadence Business System.