HEIDENHAIN iTNC 530 (34049x-08) Cycle programming - Manual (Page 168)

168 Fixed cycles: pocket milling / stud milling / slot milling
5.7 CIR
C
ULAR S
T
UD (Cy
cle 257
, DIN/ISO:
G257)
5.7 CIRCULAR STUD (Cycle 257,
DIN/ISO: G257)
Cycle run
Use Cycle 257 to machine a circular stud. If the diameter of the
workpiece blank is greater than the maximum possible stepover, then
the TNC performs a spiral infeed until the finished diameter has been
machined.
1
The tool moves from the cycle starting position (stud center) to the
starting position for stud machining. With the polar angle you
specify the starting position with respect to the stud center using
parameter Q376
2 If the tool is at the 2nd set-up clearance, it moves at rapid traverse
FMAX
to the set-up clearance, and from there it advances to the first
plunging depth at the feed rate for plunging.
3 The tool then moves tangentially on a helical path to the stud
contour and machines one revolution.
4 If the finished diameter cannot be machined with one revolution,
the TNC performs helical infeed movements until the finished
diameter is reached. The TNC takes the dimensions of the
workpiece blank diameter, the finished diameter, and the
permitted stepover into account.
5 The TNC retracts the tool on a helical path from the contour.
6 If more than one plunging movement is required, the tool repeats
the plunging movement at the point next to the departure
movement.
7 This process is repeated until the programmed stud depth is
reached.
8 At the end of the cycle, the TNC positions the tool—after the
helical departure movement—in the tool axis to the 2nd set-up
clearance defined in the cycle, and finally to the center of the stud.
X
Y