HEIDENHAIN CNC Pilot 4290 V7.1 - Manual (Page 239)

HEIDENHAIN CNC PILOT 4290 239
4.22 Thr
e
ad Cy
cles
4.22 Thread Cycles
Overview of threading cycles
„ G31 machines simple threads, successions of threads and multi-
start threads with G24, G34 or G37 Geo (see “Thread cycle G31” on
page 240). G31 does not switch the velocity feedforward. If you
want to work without velocity feedforward you can switch it off
before the thread cycle.
„ G32 cuts a simple thread in any desired direction and position (see
“Simple thread cycle G32” on page 242). G32 is used to deactivate
velocity feedforward.
„ G33 conducts a single thread cut. The direction of the single thread
cut is as desired (see “Thread single path G33” on page 244). G33
does not switch the velocity feedforward. If you want to work
without velocity feedforward you can switch it off before the thread
cycle.
Smooth threading: With smooth threading, the CNC PILOT
accelerates over cubic acceleration ramps. The smooth threading
prevents vibration during thread cutting on lathes with direct drives
(see “Thread switch G933” on page 239).
Thread switch G933
With smooth threading the CNC PILOT accelerates during thread
run-in, thread run-out and during direction reversal (successive
threads) over cubic acceleration ramps. The smooth threading
prevents vibration during thread cutting on lathes with direct drives.
G933 switches the smooth threading on/off. G933 is a modal function.
It can be programmed at any location, even in the G33 block. With
program start, with M30 and M99 the smooth threading is switched
off.
The smooth threading is supported by NC software 368 650-22 and
later. As of software version 368 650-23, the smooth threading can be
activated on a sustained basis by parameter. Set bit 5 of the expansion
stage code (MP 1103, ..).
Parameters
Q Thread switch
„ Q=0: Smooth threading off
„ Q=1: Smooth threading on