2 Drilling Cycles and Drilling Patterns 03.962.1 Drilling cycles 2© Siemens AG, 2002. All rights reserved2-86 SINUMERIK 840D/840Di/810D Programming Guide Cycles (PGZ) – 11.02 EditionDescription of parametersSee Subsection 2.1.2. (Drilling, Centering –CYCLE81) for a description of parameters RTP,RFP, SDIS, DP, DPRDTB (dwell time)You program the dwell time in seconds. It works inparameter ENC depending on which technologicalvariant you selected.SDR (direction of rotation for retraction)The direction of rotation for retraction when tapping isprogrammed in parameter SDR. For tapping with anencoder, the direction of spindle travel can be reversedautomatically, for which SDR=0 is set.SDAC (direction of rotation)As the cycle can also be called modally (see Section2.2), it requires a direction of rotation for tapping furtherthreads. This is programmed in parameter SDAC andcorresponds to the direction of rotation programmedbefore the first call in the higher-level program. IfSDR=0, the value assigned to SDAC is of nosignificance in the cycle and can be omitted from theparameterization.ENC (tapping)If tapping is to be performed without encoder althoughan encoder exists, parameter ENC must be assignedthe value 1.However, if no encoder exists and the parameter isassigned the value 0, it is ignored in the cycle.• Tapping without encoder with input of the lead (SW 6.2 or higher):From SW 6.2 you can calculate the correlationbetween feed and speed via the programmed leadwithin the cycle for tapping without encoder (G63thread). The speed must be programmed before thecycle is called.You can specify the lead either via MPIT (metricthread unit) or via PIT (thread lead as value) just asfor tapping without encoder.11.02
