HEIDENHAIN iTNC 530 (60642x-04) Cycle programming - Manual (Page 115)

HEIDENHAIN iTNC 530 115
4.6 THREAD MILLING (Cy
c
le
262, DIN/ISO:
G262)
4.6 THREAD MILLING (Cycle 262,
DIN/ISO: G262)
Cycle run
1 The TNC positions the tool in the spindle axis at rapid traverse FMAX
to the entered set-up clearance above the workpiece surface.
2 The tool moves at the programmed feed rate for pre-positioning to
the starting plane. The starting plane is derived from the algebraic
sign of the thread pitch, the milling method (climb or up-cut milling)
and the number of threads per step.
3 The tool then approaches the thread diameter tangentially in a
helical movement. Before the helical approach, a compensating
motion of the tool axis is carried out in order to begin at the
programmed starting plane for the thread path.
4 Depending on the setting of the parameter for the number of
threads, the tool mills the thread in one helical movement, in
several offset helical movements or in one continuous helical
movement.
5 After this, the tool departs the contour tangentially and returns to
the starting point in the working plane.
6 At the end of the cycle, the TNC retracts the tool at rapid traverse
to the set-up clearance, or—if programmed—to the 2nd set-up
clearance.
Please note while programming:
X
Y
Q207
Q335
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 "thread depth"
determines the working direction. If you program the
thread DEPTH = 0, the cycle will not be executed.
The nominal thread diameter is approached in a semi-circle
from the center. A pre-positioning movement to the side
is carried out if the tool diameter is smaller than the
nominal thread diameter by four times the thread pitch.
Note that the TNC makes a compensation movement in
the tool axis before the approach movement. The length
of the compensation movement is at most half of the
thread pitch. Ensure sufficient space in the hole!
If you change the thread depth, the TNC automatically
changes the starting point for the helical movement.