Originally Published EMDM
January/February 2004
Technology News
Cassette Moulding Can Reduce Lead Time in Low-Volume Production of Medical Parts |
| By using a cassette mould, an Ireland-based subcontractor can supply production-quality parts in as few as two weeks. |
Similar to the master unit die process, cassette moulding can offer unique advantages for tooling development and the low-volume production of medical device components. One of the key benefits, says Sean O’Dwyer, sales engineer at Screentech Ltd. (Bray, Co. Wicklow, Ireland), is a dramatic reduction in lead time. “Instead of the usual 11 to 12 weeks, cassette moulding allows us to make production-quality parts within three weeks. In some cases, the lead time can be slashed to two weeks. Tooling costs are also reduced,” he adds. The process enabled Screentech to mould parts for a major medical device manufacturer and help it to get a product to market even before the production mould had been completed.
Screentech stocks an inventory of ready-to-machine blank cassette plates. They are manufactured from hardened Stavax, similar to production moulds. Once the plates have been machined, they are placed in the master mould, which clamps the plates together and removes the sprue and runner after moulding has been completed.
The quality of the moulded parts matches production standards, according to Screentech. They can be used in everything from bench testing and clinical trials to initial production runs. The firm cites one case in which a cassette designed for the development process was used to mould the first 100,000 units of a product.
Cassette moulding can be hugely beneficial during the development stage, stresses O’Dwyer. For example, making a change to a cassette plate following functional testing can be done much more cost-effectively than with traditional tooling. Multiple material trials can be conducted, allowing the final production mould to be designed with optimal shrinkage and flow characteristics. In addition, the cassette plate’s gating and cores duplicate those used in the production mould. This enables tooling-related issues to be resolved before production begins.
When Screentech opened for business in the early 1990s, it supplied contract moulding and printing services to the telecommunications industry. To provide its customers with high-quality clear lenses, the firm installed a Class 100,000 cleanroom. However, the volatility of the telecoms industry led the firm to explore other markets. “Pat Whyte, the consultant who installed the cleanroom, had been involved in the medical field,” recalls O’Dwyer. That started some wheels turning, and Whyte joined Screentech as a partner about 31¼2 years ago. He is now responsible for the company’s medical technology activities. The refocusing has been a qualified success. Screentech currently does about 40% of its business with medical device OEMs.
Norbert
Sparrow
Copyright ©2003 European Medical Device Manufacturer
