Kroeplin, a traditional engineering company from Schlüchtern, has been producing gauges for nearly 80 years. Its products are mainly used to quickly measure dimensions of parts located in difficult-to-reach areas. For many decades, its measurement instruments were mechanical, but over the last 15 years they’ve been increasingly replaced by electronic measuring devices. These are not only highly accurate, they also offer useful features such as digital displays and minimum/maximum functions. No matter which measurement principle is used, rigorous testing is essential. For the last 20 years, Kroeplin has turned to the Ilmenau-based Steinbeis Transfer Center for Quality Assurance and Image Processing for its professional and reliable support. The specialists from Ilmenau develop and design high-precision testing technology for hundreds of different types of quick-test gauges.
Quick-test gauges are used in a variety of ways: to measure inner-grooves, wall thickness, outer measurements but also for dental applications. Steinbeis engineers have developed the gauge technology for each new generation of mechanical and electronic testing device. Since electronic quick-test gauges provide linearization, based on measurement deviation functions, the requirements have become more complex.
The hardware used in the test system is now in its third generation. A high-precision incremental length measuring system with deviations down to the sub-micrometer range is used as reference. The gauges always have a fixed arm and a moving sensor arm on a swivel. They are placed on an aerodynamic bearing so movements can be compensated for when the tips of the feeler arm slide into position and are moved automatically. The resulting target position is used to determine the actual value measured by the gauge, the according deviation curve is plotted on a screen. With mechanical gauges this curve is used for adjustment, with electronic ones it forms the basis for the linear approximation function to be stored in the gauge its microprocessor. Based on the testing that follows, a test certificate is issued for delivery with each gauge.
The comprehensive testing software programmed by the Ilmenau Steinbeis Transfer Center comes complete with printing, administration and service functions. Future innovations at Kroeplin GmbH will pose new challenges to testing technology, so that further cooperation with the Steinbeis Transfer Center Ilmenau will be extended into a third decade. Clients around the world benefit from the know-how offered by both business partners, as Kroeplin also produces quick-test gauges for Japanese, American and Swiss customers.
With each project, the Steinbeis Transfer Center for Quality Assurance and Image Processing has continuously expanded its understanding of high-precision incremental measuring processes, precision instrument construction and software development. Aside from its collaboration with Kroeplin, the center is involved in a variety of projects with domestic and foreign companies, most of them focussing on industrial image processing for precision geometry measurements.
Klaus-Jürgen Rennert
Steinbeis Transfer Center Quality Assurance and Image Processing (Ilmenau)