Bayer MaterialScience Contributes To New Design Of Computer Tomography Equipment

Pittsburgh — Bayer MaterialScience is contributing to a fresh, new design of the cladding sections of computer tomography equipment from Siemens with its Baydur® 110 polyurethane. The manufacturer of the polyurethane components, Thieme GmbH & Co., has incorporated key design elements in this high-tech piece of medical machinery. The front, molded in one shot, and the rear wall measure nearly 6.6 X 6.6 feet with a wall thickness of just 0.2 inches.

Siemens' Somatom Volume Zoom, said to be the fastest computer tomograph in the world, allows doctors to conduct an internal examination of their patients more accurately, painlessly and quickly than before.

The Baydur 110 polyurethane provides for an attractive machine casing. "A projected surface area of this size was a challenge for us, but the front and rear-wall design posed specific challenges", said Wolfgang Kurrus, Thieme's project leader. "We had to develop a mold support and a mold that can maintain a locking force of over 550 tons at an internal pressure of 15 bar. Our success shows the tremendous possibilities offered by polyurethanes."

Specifically, the ratio of wall thickness to flow length that proved possible with Baydur 110 would not have been feasible with thermoplastics. Despite the thin walls, both the large sections and the smaller side elements are rigid enough to give good stability over the entire housing in combination with metal reinforcements. With thermoplastic materials, accurately positioned apertures, slits, ribs and domes would have to be created at a later stage. With Baydur, it was possible to mold them in, making design work easier. This polyurethane is also extremely high-impact and gives the complex internal workings of the tomograph — around 1,540 pounds of metal and electronics moves once around the patient in half of a second — optimum protection.

"Baydur 110 has proven to have the best combination of properties," said Kurrus. "The redesigned Somatom housing now has fewer parts and is underpinned by a modern, up-to-date design that can be produced cost-effectively."

SOURCE: Bayer Corporation