Siemens SINUMERIK 840D Programming Manual page 174

Milling Cycles
3
3.13 Milling rectangular spigots - CYCLE76 (SW 5.3 and later)
Depth infeed:
• Infeed to safety clearance
• Insertion to machining depth
The first machining depth is the product of:
• the total depth,
• the final machining allowance and
• the maximum possible depth infeed.
Sequence of motions for finishing (VARI=X2)
Depending on the setting of parameters _FAL and
_FALD, a finishing operation is performed on the spigot
surface or base or both. The approach strategy
matches the motions in the plane executed for roughing
operations.
Description of parameters
See Section 2.1.2. (Drilling, Centering – CYCLE81)
for a description of parameters RTP, RFP, SDIS,
DP, DPR.
See Section 3.9 for a description of parameters
_MID, _FAL, _FALD, _FFP1, _FFD.
See Section 3.2 for cycle setting data _ZSD[2].
_LENG, _WID and _CRAD (spigot length, spigot
width and corner radius)
The shape of a spigot in the plane is determined with
parameters _LENG, _WID and _CRAD.
The spigot can be dimensioned from the center or
from one corner point. When dimensioning from a
corner point, use _LENG and _WID with sign.
The absolute length value (_LENG) always refers to
the abscissa (with a plane angle of zero degrees).
_PA, _PO (reference point)
Parameters _PA and _PO are set to define the
reference point of the spigot in abscissa and ordinate.
This is either the spigot center point or a corner
point. The value of this parameter depends on cycle
setting data bit _ZSD[2]:
• 0 means spigot center point
• 1 means corner point
When the spigot is dimensioned from a corner, the
length and width parameters must be entered with sign
3-174
Spigot dimensioned from center point
Y
_PA
Spigot dimensioned from corner point
Y
_PA
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide, Cycles (PGZ) - 04.00 Edition
03.96
04.00
3
_STA
_CRAD
X
_STA
X
 Siemens AG 2000 All rights reserved.