3 adaptive feed control software option (afc), Application, Adaptive feed control software option (afc) – HEIDENHAIN TNC 640 (34059x-04) User Manual
Page 383: Adaptive feed control software option (afc) 11.3
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Adaptive Feed Control Software Option (AFC) 11.3
11
TNC 640 | User's Manual
HEIDENHAIN Conversational Programming | 3/2014
383
11.3
Adaptive Feed Control Software
Option (AFC)
Application
This feature must be enabled and adapted by the
machine tool builder.
Refer to your machine manual.
Your machine tool builder may also have specified
whether the TNC uses the spindle power or any
other value as the input value for the feed control.
Adaptive feed control is not intended for tools with
diameters less than 5 mm. This limit diameter might
also be greater if the spindle’s rated power is very
high.
Do not work with adaptive feed control in operations
in which the feed rate and spindle speed must be
adapted to each other, such as tapping.
In adaptive feed control the TNC automatically controls the feed
rate during program run as a function of the current spindle power
consumption. The spindle power required for each machining
step is to be recorded in a teach-in cut and saved by the TNC in a
file belonging to the part program. When each machining step is
started, which is normally when the spindle is switched on, the
TNC controls the feed rate so that it remains within the limits that
you have defined.
This makes it possible to avoid negative effects on the tool, the
workpiece, and the machine that might be caused by changing
cutting conditions. Cutting conditions are changed particularly by:
Tool wear
Fluctuating cutting depths that occur especially with cast parts
Fluctuating hardness caused by material flaws