Helmut Christmann GmbH based in Birkenfeld near Pforzheim in the Baden region of south-west Germany has made a name for itself as a contract manufacturer of high-precision parts involving a variety of different production techniques. In order to achieve the necessary precision, and assure process safety in production, the company relies on machine-integrated production measurement technology from BLUM.
"We specialise in high-precision parts involving different production techniques. We turn parts that are just 0.2 millimetres in diameter, and carry out electrical discharge machining (EDM) on wire that is just three hundredths of a millimetre thick," reports CEO Marcus Christmann. "We mass-produce carbide metal with a contour accuracy of plus/minus two thousandths of a millimetre. To assure such levels of precision, we employ workpiece and tool measuring technology on our machining centres." Whereas many other contract manufacturers specialise in one production technique, Christmann operates a large portfolio of machinery covering a wide range of different processes, from milling and turning to EDM and grinding. The company has acquired advanced levels of know-how in the production of high-precision parts over a number of years – including in measuring technology.
In-machine measurement is a common practice in milling processes nowadays. Probes are mounted on tool holders and fitted into the spindle as required. The machine then scans the desired measuring points. The measurement signals are relayed to the machine optically or wirelessly, depending on the design variant. This means complex measuring tasks can be automatically integrated into machining programmes, with no need to unclamp the workpiece, transport it to the measuring room, and clamp it back on. Eliminating the need to remove the workpiece is especially important in the production of high-precision parts, as it is practically impossible to clamp a workpiece twice in an absolutely identical way. In-machine measurement also saves a great deal of time, as well as reducing scrap rates.