Drill And Thread Milling (Cycle78) - Siemens SINUMERIK 828D Operating Manual

9.1.9

Drill and thread milling (CYCLE78)

Function
You can use a drill and thread milling cutter to manufacture an internal thread with a specific
depth and pitch in one operation. This means that you can use the same tool for drilling and
thread milling, a change of tool is superfluous.
The thread can be machined as a right- or left-hand thread.
Clamping the spindle
For ShopTurn, the "Clamp spindle" function can be set up by the machine manufacturer.
See also
Clamping the spindle (Page 247)
Approach/retraction
1. The tool traverses with rapid traverse to the safety clearance.
2. If pre-drilling is required, the tool traverses at a reduced drilling feedrate to the predrilling
depth defined in a setting data (ShopMill/ShopTurn). When programming in G code, the
predrilling depth can be programmed using an input parameter.
1. The tool bores at drilling feedrate F1 to the first drilling depth D. If the final drilling depth
Z1 is not reached, the tool will travel back to the workpiece surface in rapid traverse for
stock removal. Then the tool will traverse with rapid traverse to a position 1 mm above the
drilling depth previously achieved - allowing it to continue drilling at drill feedrate F1 at the
next infeed. Parameter "DF" is taken into account from the 2nd infeed and higher (refer to
the table "Parameters").
2. If another feedrate FR is required for through-boring, the residual drilling depth ZR is
drilled with this feedrate.
3. If required, the tool traverses back to the workpiece surface for stock removal before
thread milling with rapid traverse.
4. The tool traverses to the starting position for thread milling.
5. The thread milling is carried out (climbing, conventional or conventional + climbing) with
milling feedrate F2. The thread milling acceleration path and deceleration path is
traversed in a semicircle with concurrent infeed in the tool axis.
Turning
Operating Manual, 01/2015, 6FC5398-8CP40-5BA2
Machine manufacturer
Please refer to the machine manufacturer's specifications.
Machine manufacturer
Please also refer to the machine manufacturer's instructions.
Programming technology functions (cycles)
9.1 Drilling
331