Siemens Sinumerik 808D Operating Manual page 42

Create Part
Program
Part 2
Basic Theory
For descriptions of RTP, RFP, SDIS and DP, please see page 40
FDEP=5 Reach first drilling hole depth. Z axis
coordinate is -5
(absolute coordinate value)
FDPR=5 From the reference plane, drill down-
wards 5mm
DAM=90 Decrement is 90
DTB=0.7 Pause 0.7 s during final tapping of
thread depth (discontinuous cutting)
DTS=0.5 Stops at the start position for 0.5 s
(for VARI=1,removal active)
FRF=1 Original effective feed rate remains
unchanged
(range:0.001~1)
VARI=0 Interruption in drilling is active
AXN=3
AXN is tool axis,under appointed
G17 use Z axis
MDEP=5 Minimal drilling depth 5 mm
VRT=1.4 Interruption in drilling, the retraction
value of the quill is 1.4 mm
DTD=0.6 Pauses at the position of final drilling
depth for 0.6 s
DIS1=1.6 When reinserting a quill, you can
program a distance limit of 1.6 mm
Operating and Programming — Milling
DTB <0: Unit is r
DTS <0: Unit is r
Feed rate modulus
VARI=1 retraction of active quill back
to reference plane
The value of AXN decides which axis
to use
This parameter activates only when
DAM <0
VRT=0 → retraction value is 1mm
VRT>0 → retraction value is appoint-
ed value
DTD <0:unit is r, DTD =0:same as
DTB
For specific explanations please refer
to the standard handbook
Page 42
DAM parameter
①DAM≠0, the first drilling operation（FDPR）cannot exceed the drilling depth. As of
the second drilling operation, the drilling is acquired from the last depth operation
(drilling depth=last drilling depth-DAM). The calculated drilling must be >DAM. If the
calculated drilling is ≤DAM, as of the next feed, the DAM value will be the feed depth
until the end of the feed. If the last remaining depth is <DAM, then drilling is per-
formed automatically until the required depth is reached.
②DAM=0,drilling depth each time is same as the 1st drilling depth (FDPR),
In case the residual depth <2xFDPR,the last 2 cutting depth are half of the residual
depth.
Example：40 mm deep hole as an example, with DAM=2 mm and DAM=0 mm feed
Feed Every feed depth/ Actual depth/
times mm mm
DAM=2
1. FDPR=10 -10
2. FDPR-DAM=10-2=8 -18
3. (FDPR-DAM)-DAM -24
=8-2=6
4. (FDPR-2DAM)- -28
DAM =6-2=4
5. (FDPR-3DAM)- -30
DAM =4-2=2
6. DAM=2 -32
7. DAM=2 -34
8. DAM=2 -36
9. DAM=2 -38
10. DAM=2 -40
s
Feed Every feed depth/ Actual depth/
times mm mm
DAM=0
1. FDPR=10 -10
2. FDPR=10 -20
3. FDPR=10 -30
Remaining depth =10 < 2xFDPR,the
remaining depth distribute by the last two
drilling
4. 5 -35
5. 5 -40
6.
7.
8.
9.
808D