Grinding with the Utmost Precision
At this stage, the tube glass beads are not perfectly round, deviating by up to 0.2 millimeters. They are subsequently ground in glass bead grinding machines to achieve precision roundness. The mechanical surface removal process also helps maintain purity standards. The next step, a polishing process carried out with the utmost care in order to protect the product, gives the valuable beads a unique surface quality. The surface roughness is smaller than or equal to 0.0005 millimeters.
The manufacturing process allows diameters from 1.0 to 12.0 millimeters. The mixing beads for the insulin syringe cylinders, for example, are made from borosilicate glass and have a diameter of 2.5 millimeters. The standard tolerance is +/–0.02 millimeters for the diameter and 0.02 millimeters for the roundness. Nevertheless, according to Dr. Hitzschke, one should not forget that in order to reach these values, up to 40 percent of the bead volume must be removed.
Quality Control Supervised by a Camera