HEIDENHAIN TNC 320 (340 551-01) - Manual (Page 199)

HEIDENHAIN TNC 320 199
8.2 Cy
cles f
o
r Dr
illing,
T
apping and Thr
ead Milling
RIGID TAPPING without a floating tap holder
NEW (Cycle 207)
The TNC cuts the thread without a floating tap holder in one or more
passes.
1 The TNC positions the tool in the tool axis at rapid traverse FMAX
to the programmed set-up clearance above the workpiece surface.
2 The tool drills to the total hole depth in one movement.
3 Once the tool has reached the total hole depth, the direction of
spindle rotation is reversed and the tool is retracted to the set-up
clearance at the end of the dwell time. If programmed, the tool
moves to the 2nd set-up clearance at FMAX.
4 The TNC stops the spindle turning at set-up clearance.
Machine and control must be specially prepared by the
machine tool builder for use of this cycle.
Before programming, note the following:
Program a positioning block for the starting point (hole
center) in the working plane with radius compensation R0.
The algebraic sign for the total hole depth parameter
determines the working direction.
The TNC calculates the feed rate from the spindle speed.
If the spindle speed override is used during tapping, the
feed rate is automatically adjusted.
The feed-rate override knob is disabled.
At the end of the cycle the spindle comes to a stop. Before
the next operation, restart the spindle with M3 (or M4).
Use the machine parameter suppressDepthErr to define
whether, if a positive depth is entered, the TNC should
output an error message (on) or not (off).
Danger of collision!
Keep in mind that the TNC reverses the calculation for pre-
positioning when a positive depth is entered. This
means that the tool moves at rapid traverse in the tool axis
at safety clearance below the workpiece surface!