In a fast-paced production environment, the efficiency, accuracy and flexibility of automated production equipment are critical factors in reducing operating costs and improving productivity.
Cepheid, based in Sunnyvale, CA, is an on-demand molecular diagnostics company that develops, manufactures and markets fully integrated systems and tests for genetic analysis in the clinical, industrial and bio-threat industries. Their systems enable rapid, sophisticated genetic testing for organisms and genetic-based diseases by automating otherwise complex manual laboratory procedures.
After developing a test to detect the presence of a specific DNA, Cepheid engineers found they were unable to produce the test's disposable reaction tubes in sufficient quantity to keep up with testing demands. It became clear that development of a new production system was necessary.
After exploring a variety of options, Cepheid turned to Stirling Engineering Inc. of San Jose, CA ó a firm specializing in the design and building of custom factory automation systems. The company offered Cepheid a design that would drastically improve assembly times, and not only provide Cepheid with the capability to produce up to 24 million parts per year, but allow it to run four separate products on the same line. The system incorporated 12 assembly stations and a cycle time of 3 sec to easily meet the desired production rate. Integral to the Stirling design was the use of metal indexing belts, provided by Belt Technologies of Agawam, MA, a leading provider of metal belt and conveyor systems for more than 30 years.
Metal belt technology offers significant advantages over other indexing systems including high strength-to-weight ratio, durability and precise positioning control. Additionally, metal belts don't stretch like standard timing belts, run without lubrication, and minimize variations in surface speed ó all resulting in increased efficiency and throughput. "After performing the financial analysis, it became clear that costs would be reduced by developing a faster part cycle time," says Cepheid Design Engineer Doug Dority. "Given the number of parts we'd be producing, the savings would be significant."
The system also provided clean, accurate, flexible processing. "The process was not only fast, it provided a very clean parts transfer, as clean as any I've seen," says Dority. "We looked at various conveyor products and had concerns with the overall mass of the systems. The obvious solution was metal belts, which provide low inertia, excellent repeatability and exceptional accuracy. Plus, in the future, we could extend the line very easily due to the flexibility of the belts, which provides a tremendous advantage. Regardless of what comes down the road, we know the metal belts provide the flexibility we need to make easy, on-the-fly adjustments."
According to Dority, the decision to use metal belts from Belt Technologies was certainly warranted. "Overall, the metal belts proved far superior than the other options we considered," he says. The system currently produces around 12 million parts per year, is easily managed by one person and is virtually maintenance-free.