HEIDENHAIN TNC 640 (34059x-01) Cycle programming - Manual (Page 61)

HEIDENHAIN TNC 640 61
3.2 CENTERING (Cy
c
le 240, DIN/ISO: G240)
3.2 CENTERING (Cycle 240,
DIN/ISO: G240)
Cycle run
1 The TNC positions the tool in the spindle axis at rapid traverse FMAX
to the set-up clearance above the workpiece surface.
2 The tool is centered at the programmed feed rate F to the entered
centering diameter or centering depth.
3 If defined, the tool remains at the centering depth.
4 Finally, the tool moves to set-up clearance or—if programmed—to
the 2nd set-up clearance at rapid traverse FMAX.
Please note while programming:
Program a positioning block for the starting point (hole
center) in the working plane with radius compensation R0.
The algebraic sign for the cycle parameter Q344 (diameter)
or Q201 (depth) determines the working direction. If you
program the diameter or depth = 0, the cycle will not be
executed.
Danger of collision!
Use the machine parameter displayDepthErr to define
whether, if a positive depth is entered, the TNC should
output an error message (on) or not (off).
Keep in mind that the TNC reverses the calculation for pre-
positioning when a positive diameter or depth is
entered. This means that the tool moves at rapid traverse
in the tool axis to set-up clearance below the workpiece
surface!