HEIDENHAIN 548431-05 User Manual page 642

9
Drilling – Machining
The parameters apply to drilling with deep-hole drilling cycle (G74).
Machining
Parameter
Drilling depth factor BTFC
Depth reduction BTRC
Diameter tolerance for drill BDT
642
Meaning
1st drilling depth: bt1 = BTFC
* db (db: Drill diameter)
2nd drilling depth: bt2 = bt1 –
BTRC
The subsequent drilling steps
are reduced accordingly
For selecting the desired drill
(centering drills, countersinks,
stepped drill, taper reamers).
Drilling diameter: DBmax =
BDT + d (DBmax: Maximum
drilling diameter)
Tool selection: DBmax > DB
> d
Organization mode of operation | Parameters
HEIDENHAIN | MANUALplus 620 | User's Manual | 12/2017