High-precision length measurement station Precimar PLM 600-2 from Mahr determines diameter values for measuring force 0 Newton In quality control, thin-walled workpieces need instruments that do not deform the specimen. The application specialist Mahr, in conjunction with the highly accurate precision length measuring machine Precimar PLM 600-2 offers a measurement procedure that enables the customer to receive results on deformable workpieces without determining the influence of the measuring force. Thin-walled workpieces, such as rolling bearing rings are highly sophisticated. If a metrology technician checks the inner or outer diameter of a bearing on a length measuring machine during quality control, the bearing can be deformed already at low applied forces. Thus, the measurement results are distorted. The application specialist Mahr offers a measuring procedure that eliminates this risk. The highly accurate precision length measuring station Precimar PLM 600-2 provides a measuring procedure in which the measuring force is downscaled by the software 828 WIN "Free Measuring" to 0 Newtons (N). This allows the real inner or outer diameter of the measuring object to be reliably determined. This method was primarily developed for the measurement of thin-walled (elastic) measuring objects that would be deformed during measurement and thus measured incorrectly. For the measurement of such measuring objects, optical or other force-free methods of measurement have been used so far (for example, pneumatic methods). Of course, a mechanical tracing length measuring machine cannot measure force-free. If the measuring machine, however, is equipped with the possibility to automatically modify the measuring force in a specified sequence, while reliably recording the corresponding measuring object, then its elastic properties can be determined in this way. The knowledge of the elastic properties of the measurement object can be used in turn to calculate the given length in the unloaded, measured force-free state of the measuring object. After probing the bearing, the measuring machine initially generates a measuring force of 1.2 N and detects the corresponding measurement value. Then, invisible to the user, the measuring force is automatically reduced in steps of 0.02 N 1.2 N to 0.8 N and the corresponding measured values are determined. The principal advantage over static measurement is the fact that the calculated length value is based on a number of individual measured values and is therefore fraught with an uncertainty lower than the respective single value. The Precimar PLM 600-2 is designed to test equipment and suitable work pieces from different production areas user-friendly, fast, safe, and with the smallest possible uncertainty. In the measuring chamber at 20° C, a measurement uncertainty of MPEE1 (0.085 + L/1500) µm is reached (L in mm). The highly accurate measuring system has a 5-axis finely adjustable universal object table, a modern PC-based machine control for several axes, including PC workstation and basic software 828 WIN "Free Measuring". Subjective influences are minimized with semi-automatic machine operation. | 
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