4.3 Workpiece mounting errors compensation on tilting tables (G122)

With G122 it is possible to compensate workpiece mounting errors on a tilting table. The procedure to be used is the following: - The workpiece mounting errors are measured and computed (normally in automatic, by means of proper measuring sequences in G61) - The rotating axes are moved to align the workpiece (faces to be machined aligned with the linear axes) - Possible activation of origins on linear axes, to compensate all mounting errors in this aligned position. - G122 is activated inserting in IJK the mounting errors along the three main linear axes. For example, if: the main machine axes are X, Y, Z and their respective logical number is 0, 1, 2. After having aligned the workpiece, the rotating axes may have any error, but the workpiece faces have been aligned with proper rotations. The mounting error measured on X is +1,5mm (i.e. the workpiece is mounted shifted of 1,5mm toward positive X direction), 0,4mm on Y and 0,1 on Z. The part-program line to activate the correction in G122 is the following: G122 I1.5 J0.4 K0.1 G122 activation The activation syntax of G122 is as follows: G122 I… J… K… where: I, J, K are the components of the mounting error respectively along X, Y, and Z axes. Some important notes: When G122 is active, no origin programming is allowed G122 is deactivated at reset The IJK parameters must be all programmed, otherwise the alarm CN2C14 INCOMPATIBLE PARAMETERS is issued (see below the case where no parameters are programmed, to activate the parameters stored in permanent memory) G122 is not compatible with G43/G44/G45, otherwise the alarm CN5B14 is generated. G122 is transparent to jog. It is allowed to program G122 in semiauto, then passing in jog without pressing reset. If a rotating axis is moved in jog, the linear axes move automatically as set by G122. Returning in semiauto from jog, with G122 active, a reset is activated, canceling the G122. To allow usage flexibility of G122, the programmed parameters IJK are stored in permanent memory. By programming G122 without parameters: G122 the last programmed parameters are restored, remaining valid also after a machine shutdown and restart. This feature may be very important during a machining restart after an interruption. G122 deactivation To deactivate the G122 correction, program the following: G122 KA0

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