Measuring Systems for Machine Tool Inspection and Acceptance Testing

Machine tool performance from the point of view of compliance to tolerances, surface definition, etc., is determined essentially by the dynamic and static accuracy of machine movement. For precision machining it is therefore important to measure and compensate motional deviations. Guidelines and standards for inspecting machine tools (ISO 230-2, ISO 230-3 and ISO 230-4, and VDI/DGQ Directive 3441) stipulate a number of measuring methods for determining dynamic and static deviations.

Heidenhain measuring systems

Conventional inspection and acceptance testing of machine tools has been limited essentially to static measurement of the geometrical machine structure without load and on controlled machines to measuring positioning accuracy. Since the results of machining depend increasingly on dynamic deviations from the nominal contour and on high acceleration in the machine tool, the finished parts are also inspected for dimensional accuracy in order to draw conclusions about the dynamic behaviour of the machine. The HEIDENHAIN measuring systems KGM and VM 182 can now be used to directly measure both dynamic and static components of deviation. The advantage of this direct inspection method over inspecting only the results of the machining lies in its separation of technological influences from machine influences, and in its capability of distinguishing individual factors of influence.

Machine tool measuringMachine Tool Builders

Machine tool builders use the results of machine accuracy inspection for the purpose of making design improvements to increase accuracy. Such measurements also help them to optimize the commissioning parameters of the control loop wherever they influence the accuracy of a CNC machine

Machine Tool User

Machine tool users can use these measuring systems for acceptance testing and regular inspection of their machine tools.