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.
The same could be said
of numerous top-tier custom fabricators and, for
that matter, any company
that doesn’t compete on
price alone.
Senior Editor Tim Heston
can be reached at timh@
thefabricator.com.
Images courtesy of
Cadence Inc., 9 Technology
Drive, Staunton, VA 24401,
800-252-3371, www.cadence
inc.com.
Figure 4
An R&D setup in the Advanced Welding Lab™ fixtures
two small parts under a low-powered laser welding
head.
Figure 5
Cadence uses laser Swiss
turning to fabricate tubes
that require both turned
and laser-cut features. The
machine accomplishes
both in one setup.
“We’re probably one of the
largest laser welding houses
that nobody has ever heard of.”
—Jack Abato, Cadence Inc.