Siemens SINUMERIK 840D Programming Manual page 111

03.96
3
Description of parameters
See Section 2.1.2. (Drilling, Centering – CYCLE81)
for a description of parameters RTP, RFP, SDIS,
DP, DPR
DIATH, KDIAM and PIT (nominal diameter, core
diameter and thread pitch)
With these parameters you define the thread data
such as, nominal diameter, core diameter and pitch.
Parameter DIATH is the outside diameter and
KDIAM the inside diameter of the thread. The travel-
in and travel-out movements are generated by the
cycle based on these parameters.
FFR (feedrate)
The value of parameter FFR is defined as the current
feedrate value for thread milling. In thread milling it is
active for the movement along the helical path.
This value is reduced in the cycle for the travel-in
and travel-out movements. Retraction is performed
outside the helical path with G0.
CDIR (direction of rotation)
You define the value for the machining direction of
the thread in this parameter.
If the parameter is assigned an illegal value, the
message
"Wrong milling direction, G3 will be generated" is
output.
In this case the cycle is continued and G3 is
automatically generated.
TYPTH (thread type)
With parameter TYPTH you determine whether an
outside or inside thread is to be machined.
CPA and CPO (center point)
With these parameters you define the center point of
the hole or spigot on which the thread is to be
machined.
 Siemens AG 2000 All rights reserved.
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide, Cycles (PGZ) - 04.00 Edition
3.3 Thread cutting - CYCLE90
Z
RTP
RFP+SDIS
RFP
Y
CPA
CDIR
Milling Cycles
3
Z
RTP
RFP+SDIS
RFP
DP
X
X
Y
CPA
CDIR
X X
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