Preconditions For The Feed; Rapid Traverse; Path Feed (F Function) - Siemens Sinumerik 840D sl Programming Manual

1.2

Preconditions for the feed

The following Section describes the feed function with which the feedrate (covered path per
minute or per rotation) of a cutting tool is defined.
1.2.1

Rapid traverse

Rapid traverse is used for positioning (G00) as well as for manual traverse with rapid
traverse (JOG). In rapid traverse, each axis is traversed with the rapid traverse rate set for
the individual axes. The rapid traversing rate is defined by the machine manufacturer and it
is specified by the machine data for the individual axes. As the axes traverse independently
of each other, each axis reaches its target point at a different time. Hence, the resulting tool
path is generally not a straight line.
1.2.2

Path feed (F function)

Note
Unless something else is specified, the unit "mm/min" always stands for feedrate of the
cutting tool in this documentation.
The feed with which a tool should be traversed in linear interpolation (G01) or circular
interpolation (G02, G03) is designated with the address character "F".
The feed of the cutting tool in "mm/min" is specified after the address character "F".
The permissible range of F values is specified in the documentation of the machine
manufacturer.
Possibly, the feed is limited by the servo system and the mechanical system in the upward
direction. The maximum feed is set in the machine data and limited to the value defined
there before an overshoot.
The path feed is generally composed of the individual speed components of all geometry
axes participating in the movement and refers to the cutter center (see the two following
figures).
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Principles of programming
1.2 Preconditions for the feed
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