Measurement Standard for Monitoring Performance of Machine Tools in Harsh Environmental Condition

The principle of in-process metrology is to obtain measurement data directly in the manufacturing process and to use them for effective process control and for reliable quality assurance. One prerequisite to significantly improve the manufacturing processes is the incorporation of traceable dimensional metrology directly on machine tools. In order to introduce traceability chain into in-process geometrical measurements, European project EMRP IND62 TIM was agreed between EC and European metrology association Euramet. One of the tasks of the project is to develop highly accurate robust temperature invariant measurement standards that can be used in the harsh environment of the production floor for verification and mapping of the measurement errors of machine tools. Laboratory for Production measurement (LTM) at the University of Maribor - Faculty of Mechanical Engineering is taking part in the consortium of this joint research project. The main task of LTM is to develop, manufacture and calibrate at least one 1D measurement standard with length up to 2 m and with thermal expansion coefficient close to 0. The task is being performed in co-operation with EMO Orodjarna and Veplas. The design is based on composite body and ceramic probing balls. Original approach of compensating thermal expansion was introduced in order to enable use of the standard in harsh environmental conditions. Furthermore, the standard is designed as a modular artifact that can be assembled in four different lengths (500 mm, 1000 mm, 1500 mm and 2000 mm). The article is presenting basic design characteristics and application possibilities of this standard.This article is based on a presentation at the conference "MacroScale 2014 - Recent developments in traceable dimensional measurements", Vienna (Austria), 28th-30th October 2014