Lehmann Rotary Tables Publications Main catalog (PGD inside!) - Page 82

Static mechanical compliance Material elasticities and their effect on workpiece accuracy: Understand them correctly and know how to respond in real-world practice NEW Overview Background TF EA +M Every material has a certain elasticity. Depending on the orientation and load, these affect the accuracy of machining in different ways. The figures and data shown here provide information on the values to be expected. T1 Optimization options MOT / KAB WMS / CNC T2 / T3 If the static stiffness is insufficient, the following may help: + Error compensation in the axis direction affected + Use of lighter clamping means + Retrofitting a counter bearing in the case of a TF rotary table + Changing the machining strategy 0° position 90° position RFX/LFX Static mechanical analysis General accessories Workpiece clamping Using FEM analyses, the compliance in P8 (see figure at right) was calculated in the respective configuration for all T-type rotary tables listed below. The deflections in the X- and Y-directions are negligible. The table below shows the deflection in the Z-direction. Depending on the workpiece weight, this information can be used to determine the approximate compliance. Compliance for load in P8 in Z-direction (approximate values) Condition: Rotary table is mounted in the specified manner and both axes are clamped with 6 bar compressed air. Technology / engineering µm/kg T1-507510 T1-510520 T1-520520 TF-507510 TF-510510 TF-510520 82 fix –0.030 –0.021 –0.024 –0.093 –0.099 –0.050 0° 90° fixX fixX1 vario varioX varioX1 varioX2 varioXA fix fixX fixX1 vario varioX varioX1 varioX2 varioXA –0.029 –0.035 –0.052 –0.070 –0.100 –0.140 –0.080 –0.120 –0.180 –0.034 –0.026 –0.041 –0.054 –0.061 –0.098 –0.057