Siemens SINUMERIK 840D Programming Manual page 312

4
Turning Cycles
4.7 Thread cutting – CYCLE97
IANG (infeed angle)
With parameter IANG you define the infeed angle. If
infeed is to be performed at right angles to the
cutting direction in the thread this parameter must be
assigned the value zero. I.e., this parameter can
also be omitted from the parameter list as it is then
automatically assigned the default value zero. If
infeed is to be performed along the flank, the
absolute value of this parameter must be no more
than half the flank angle of the tool.
The sign entered for this parameter defines how this
infeed is performed. If a positive value is entered,
infeed is always performed on the same flank, if a
negative value is entered, infeed is performed
alternately on both flanks. The infeed type on both
flanks alternately can only be used for cylindrical
threads. However, if a negative value is assigned to
parameter IANG for a tapered thread, the cycle
automatically performs a flank infeed along one
flank.
NSP (starting point offset)
Under this parameter you can program the angular
value that defines the point of the first cut for the first
thread turn on the circumference on the turned part.
This value is a starting point offset. The parameter
can be assigned any value between 0.0001 and
+359.9999 degrees. If no starting point offset has
been entered or the parameter has been omitted
from the parameter list, the first thread automatically
starts at the zero degrees mark.
4-312
IANG<=
Infeed along
one flank
SINUMERIK 840D/840Di/810D Programming Guide Cycles (PGZ) – 11.02 Edition
4
03.96
10.00
ε
ε
ε
2
Infeed on
alternate flanks
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