Originally Published EMDM
March/April 2004
INDUSTRY NEWS
Micromoulding Technique Pumps New Life into Cardiovascular Device |
| By replacing a machined stainless-steel part in a cardiovascular device with a component moulded from a polyamide-imide, a contract moulder was able to substantially reduce material and labour costs. |
A polyamide-imide material developed by Solvay Advanced Polymers LLC (Alpharetta, GA, USA) has several desirable properties for device OEMs. Sold under the Torlon name, the polymer combines high strength at temperatures up to 260°C with creep and wear resistance.
Nevertheless, many manufacturers have shied away from using it to mould parts, because “without the proper equipment and process controls, it can be difficult to work with,” says Scott Herbert, general manager at
RapidWerks LLC (Chicago, IL, USA). The company has found a way to sidestep potential problems by using a Microsystem (MS) 50 moulding machine from Battenfeld along with some proprietary processes. (Herbert says that more than US $700,000 worth of quality inspection systems support the MS 50.) To illustrate its capabilities, the firm displayed a
micromoulded part used in a cardiovascular device at the recent MD&M West show in Anaheim, CA, USA.
“Our customers are always asking us to make it smaller, faster, and cheaper,” says Herbert. “We determined that replacing a machined stainless-steel part with a moulded plastic component would cause material and labour costs to plummet. But we needed to source a material that could achieve metallike performance,” adds Herbert. Enter Torlon 4203L.
“The component operates at several thousand rpm under a load. So we needed a low-friction material with exceptional strength and wear resistance.” In addition, the part is subjected to substantial heat, so the material had to be stable at high temperatures. “Torlon 4203L is the only high-performance plastic we found that met all of these requirements. It allowed us to produce a complex moulded part weighing only 4.2 mg that has performance characteristics similar to metal,” says Herbert.
Rapidwerks offers medical device OEMs an array of services from parts design and engineering to contract moulding and assembly. The company has a Class 10,000 cleanroom. “The Microsystem 50 moulding cell is itself a Class 10 cleanroom,” adds Herbert, “so it functions as a cleanroom within a cleanroom.”
To learn more about Torlon materials, contact Solvay Advanced Polymers LLC, 4500 McGinnis Ferry Rd., Alpharetta, GA 30005, USA; phone: +1 770 7728200; fax: +1 770 7728213; Internet:
www.solvayadvancedpolymers.com.
For more information about services provided by Rapidwerks, contact the firm at 7444 W. Wilson Ave., Chicago, IL 60706, USA; phone: +1 708 4572336; fax: +1 708 4572672; Internet:
www.rapidwerks.com.
Norbert
Sparrow
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