Programming and Operating Manual (Milling)
6FC5398-4DP10-0BA1, 01/2014
125
9.4
Drilling cycles
9.4.1
General information
Drilling cycles are motional sequences specified according to DIN 66025 for drilling, boring, tapping, etc.
They are called in the form of a subroutine with a defined name and a parameter list.
The drilling cycles can be modal, that is, they are executed at the end of each block containing motion commands. Further
cycles created by the user can also be called modally.
There are two types of parameters:
●
Geometrical parameters
●
Machining parameters
The geometrical parameters are identical for all drilling cycles, drilling pattern cycles and milling cycles. They define the
reference and retraction planes, the safety clearance and the absolute or relative final drilling depth. Geometrical parameters
are assigned once during the first drilling cycle CYCLE81.
See the following illustration for drilling, centering - CYCLE81:
The machining parameters have a different meaning and effect in the individual cycles. They are therefore programmed in
each cycle separately.
9.4.2
Requirements
Call and return conditions
Drilling cycles are programmed independently of the actual axis names. The drilling position must be approached in the
higher-level program before the cycle is called.
The required values for feedrate, spindle speed and direction of spindle rotation must be programmed in the part program if
there are no defining parameters in the drilling cycle.
The G functions and the current data record active before the cycle was called remain active beyond the cycle.
Plane definition
In the case of drilling cycles, it is generally assumed that the current workpiece coordinate system in which the machining
operation is to be performed is to be defined by selecting plane G17, G18 or G19 and activating a programmable offset. The
drilling axis is always the axis of this coordinate system which stands vertically to the current plane.
A tool length compensation must be selected before the cycle is called. Its effect is always perpendicular to the selected
plane and remains active even after the end of the cycle.
