HEIDENHAIN SW 54843x-03 DIN Programming - Manual (Page 82)

82 smart.Turn units
2.4 Units—Centr
ic dr
illing
"Centric tapping" unit
The unit cuts axial threads using stationary tools.
Unit name: G73_ZENTR / Cycle: G73 (see page 328)
Retraction length L: Use this parameter for floating tap holders. The
cycle calculates a new nominal pitch on the basis of the thread depth,
the programmed pitch, and the "retraction length." The nominal pitch
is somewhat smaller than the pitch of the tap. During tapping, the tap
is pulled away from the chuck by the retraction length. With this
method you can achieve higher service life from the taps.
Access to the technology database:
 Machining operation: Tapping
 Affected parameters: S
Cycle form
Z1
Start point drill (starting point of hole)
Z2 End point drill (end point of hole)
NS Starting block no. of contour
X Start point drill (starting point of hole; diameter value)—
(range: –2 mm < X < 2 mm; default: 0)
F1 Thread pitch
B Run-in length
L Retraction length when using floating tap holders (default:
0)
SR Retraction speed (default: Shaft speed for tapping)
SP Chip breaking depth
SI Retraction distance
Further forms: see page 60