Fraunhofer pioneers ultrasound detectors
Susan English
Ann Arbor, MI – A highly sensitive ultrasound method of detection of unwanted particles or tiny gas bubbles forming in pipelines in medical, pharmaceutical, environmental and manufacturing processes has been developed by the Fraunhofer Institute for Biomedical Engineering in St. Ingbert, Germany. Often filters cannot prevent these unwanted particles or bubbles from forming. The new technique reliably detects bubbles larger than 10 µm or solid particles larger than around 100 µm, minimizing production of foreign bodies and localizing their source, Also, with opaque or light-sensitive liquids, it succeeds where conventional optical checking methods fail. Almost any pipe diameter and flow rate can be monitored, making the ultrasound method suitable for all applications where particles in fluids must be measured.
In the application of surface coatings, the slightest impurity can ruin a smooth surface and prevent complete coverage. When they dry, bubbles burst, leaving tiny craters, while solid particles stand out on the surface, resulting in a high reject rate. Such faults in the sub-millimeter range are difficult to detect and often go unnoticed until goods are actually received. The new detector`s ultrasonic sensors are made of extremely durable and chemically inert material, and are encapsulated in a ring, allowing the detector to be used in ultraclean rooms or in areas where hygiene is critical. Control electronics carry out measurements automatically, transmitting data to a monitoring computer. n