Program Structure; Basic Principles; Machining Planes - Siemens SINUMERIK 840D sl Operating Manual

8.3

Program structure

G-code programs can always be freely programmed. The most important commands that are
normally included are:
● Set a machining plane
● Call a tool (T and D)
● Call a zero offset
● Technology values such as feedrate (F), feedrate type (G94, G95,....), speed and direction
of rotation of the spindle (S and M)
● Positions and calls, technology functions (cycles)
● End of program
For G-code programs, before calling cycles, a tool must be selected and the required
technology values F, S programmed.
A blank can be specified for simultaneous recording.
8.4

Basic principles

8.4.1

Machining planes

A plane is defined by means of two coordinate axes. The third coordinate axis (tool axis) is
perpendicular to this plane and determines the infeed direction of the tool (e.g. for 2½-D
machining).
When programming, it is necessary to specify the working plane so that the control system
can calculate the tool offset values correctly. The plane is also relevant to certain types of
circular programming and polar coordinates.
Working planes
Working planes are defined as follows:
Plane
X/Y
Grinding
Operating Manual, 05/2017, A5E40869190
Tool axis
G17 Z
Generating a G-code program
8.4 Basic principles
195