Siemens SINUMERIK 840D Programming Manual page 267

03.96
4
4.10 Extended stock removal cycle - CYCLE950 (SW 5.3 and later)
_MID (infeed depth for roughing)
The infeed depth for roughing is programmed with the
parameter _MID. Roughing steps are generated with
this infeed until the remaining depth is less than twice
the infeed depth. Then two steps are performed each at
half of the remaining depth. _MID is interpreted as a
radius or diameter depending on the value of cycle
setting data _ZSD[0] if the facing axis is involved in the
infeed for roughing.
_ZSD[0]=0: _MID is interpreted according to the G
group for radius/diameter programming, as a radius
with DIAMOF, otherwise as a diameter.
_ZSD[0]=1: _MID is a radius value
_ZSD[0]=2: _MID is a diameter value
_FALZ, _FALX (machining allowance)
A finishing allowance for rough cuts is specified by
parameter FALZ (for Z axis) and FALX (for X axis).
Roughing is always performed to these final machining
allowances.
If no machining allowances are programmed, stock
removal is performed up to the end contour during
roughing.
If final machining allowances are programmed, these
are applied correspondingly.
_FF1, _FF2, _FF3 and FF4 (feedrate)
Separate feedrates can be specified for roughing
and finishing, as shown in the figure opposite.
Separate feedrates apply for longitudinal (_FF1) and
face (_FF2) during roughing. If inclined or circular path
sections are traversed when machining the contour, the
appropriate feedrate is calculated automatically inside
the cycle.
The feedrates programmed at the contour are active
during finishing. If none are programmed there, the
finishing feedrate in _FF3 and the feedrates at radii
and chamfers in _FF4 apply to these contour
transition elements.
(see sample program 1 for programming of the parts
in the figure below)
 Siemens AG 2000 All rights reserved.
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide, Cycles (PGZ) - 04.00 Edition
Turning Cycles
roughing
X
_FF2
_FF1
resulting feed
from_FF1 and
_FF2
finishing
_FF3
X
_FF4 (chamfer)
_FF4 (radius)
4
G1/G2/G3
G0
Z
_FF3
_FF3
Z
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