an endoscopy device used in
minimally invasive surgeries. The company produces metal
stampings and subassemblies for the medical/surgical,
automotive, defense/aerospace and other specialty industrial
markets.
OKAY Industries worked with its customer, a major medical
device manufacturer, to jointly develop the low-cost endoscopy
assembly—an articulating tube that could be controlled by guide
wires during surgery. The tube, known as an articulation joint,
is a patent-pending stamped stainless-steel link assembly with
28 springs. OKAY partnered with its customer to develop the
sophisticated component, typically manufactured as a laser-cut
and welded tube assembly, as a significantly lower-cost stamping
while maintaining critical features. The process is controlled,
monitored and maintained to consistently produce high-quality
parts.
Manufacture of the articulation joint is challenging due to
the complex assembly process required, tolerances on key
dimensions and target cost. The initial manufacturing method
called for laser cutting stainless-steel tubing and then welding
springs to the individual links—cost-effective for prototypes
and low-volume applications. But for higher-volume production,
in excess of one million units per year, a metal-stamped and
welded assembly is more cost-effective.
OKAY employed its Production Proven Prototyping process to
utilize the same tooling concepts, sequence of operations and
grain direction that would be used in the production tool.
Component strength, cracking, surface finish, burrs/edge
condition and feature-tolerance capability were a few of the
concerns that OKAY assessed. The primary reason for prototyping
is to verify that the component or assembly will function as
intended in its final application. However, for metal stampings,
especially in this case, it was critical to go beyond
prototyping for fit, form and function and think ahead to
manufacturing. Prototyping of metal stampings in this way
allowed OKAY to determine if the stamping process was stable and
capable, and if cost expectations could be achieved. It also
allowed the company to identify opportunities for improvements
in cost and quality of the component or assembly.
Following the joint development effort and prototyping by
OKAY, the patent-pending manufacturing process was adopted.
Here, individual links are stamped and interconnected as a
complete set to maintain their locations during weld assembly.
After all of the inter-connected flat links have been joined via
laser-welded springs, the links are separated and the assembled
articulation joint is formed into its finished diameter. To
reconnect the open ends of each link, a laser operation seam
welds the last row of internal springs across each link from end
to end.
Using metal stampings to produce links in place of laser-cut
tubing has provided tremendous cost savings for the customer.
Additionally, the ability to weld the majority of the springs in
place while the links are in the flat state simplified
tooling/welding-fixture design and reduced the project’s capital
cost. Also, with the automated laser-welding operation and
integration of the automated rollforming operation, the customer
is ensured that every part will meet print specifications
without requiring secondary operations.
One far-reaching advantage is the fact that this R&D effort
by OKAY has uncovered other opportunities for this technology to
benefit customers in several industries that seek to reduce
costs by developing articulation joints via the stamping
process.
The Product Development Award is one of eight Awards of
Excellence in Metalforming, presented annually by PMA. Sponsored
by Ulbrich Stainless Steels and Special Metals, Inc., North
Haven, CT, it acknowledges a manufacturing company that
demonstrates outstanding innovation in developing and
manufacturing a product that best uses metal in place of a
nonmetal competitive material. Along with recognition in
industry publications and at exhibitions, OKAY will receive a
$1,500 cash prize
which OKAY has elected to
contribute to the Central Connecticut State University School of
Technology.
PMA is the full-service trade association representing the
$91-billion metalforming industry of North America—the industry
that creates precision metal products using stamping,
fabricating and other value-added processes. Its nearly 1,200
member companies include metal stampers, fabricators, spinners,
slide formers and roll formers as well as suppliers of
equipment, materials and services to the industry. Members are
located in 30 countries, with the majority found in North
America―in 41 states of the United States as well as Canada and
Mexico.
EDITOR’S NOTE: More information on PMA’s Awards of Excellence
in Metalforming is available at
