HEIDENHAIN TNC 640 (34059x-05) Cycle programming User Manual

Page 146

Fixed Cycles: Pocket Milling / Stud Milling / Slot Milling

5.3

CIRCULAR POCKET (Cycle 252, DIN/ISO: G252)

146

TNC 640 | User's Manual Cycle Programming | 1/2015

Finishing

1 Inasmuch as finishing allowances are defined, the TNC then

finishes the pocket walls, in multiple infeeds if so specified.

2 The TNC positions the tool in the tool axis in front of the

pocket wall, taking the finishing allowance Q368 and the set-up
clearance Q200 into account.

3 The TNC clears the pocket from the inside out until the diameter

Q223 is reached.

4 Then the TNC again positions the tool in the tool axis in front

of the pocket wall, taking the finishing allowance Q368 and the
set-up clearance Q200 into account, and repeats the finishing
process of the pocket wall at the next depth.

5 The TNC repeats this process until the programmed diameter is

reached.

6 After machining to the diameter Q223, the TNC retracts the

tool tangentially by the finishing allowance Q368 plus the set-
up clearance Q200 in the working plane, then retracts at rapid
traverse to the set-up clearance Q200 in the tool axis and
returns to the pocket center.

7 Next, the TNC moves the tool in the tool axis to the depth Q201

and finishes the floor of the pocket from the inside out. The
pocket floor is approached tangentially.

8 The TNC repeats this process until the depth Q201 plus Q369 is

reached.

9 Finally, the tool moves away from the pocket wall tangentially

by the set-up clearance Q200, then retracts at rapid traverse to
the set-up clearance Q200 in the tool axis and returns at rapid
traverse to the pocket center.