2 opening programs and entering, Organization of an nc program in din/iso format, Define the blank: g30/g31 – HEIDENHAIN TNC 320 (34055x-06) ISO programming User Manual
Page 83: Opening programs and entering, Opening programs and entering 3.2
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Opening programs and entering
3.2
3
TNC 320 | User's Manual for DIN/ISO Programming | 5/2013
83
3.2
Opening programs and entering
Organization of an NC program in DIN/ISO format
A part program consists of a series of program blocks. The figure at
right illustrates the elements of a block.
The TNC numbers the blocks of a part program automatically
depending on machine parameter
blockIncrement
(105409). The
machine parameter
blockIncrement
(105409) defines the block
number increment.
The first block of a program is identified by
%, the program name
and the active unit of measure.
The subsequent blocks contain information on:
The workpiece blank
Tool calls
Approaching a safe position
Feed rates and spindle speeds, as well as
Path contours, cycles and other functions
The last block of a program is identified by
N99999999 the
program name and the active unit of measure.
After each tool call, HEIDENHAIN recommends
always traversing to a safe position from which the
TNC can position the tool for machining without
causing a collision!
Block number
Path function
Words
Block
Define the blank: G30/G31
Immediately after initiating a new program, you define a cuboid
workpiece blank. If you wish to define the blank at a later stage,
press the SPEC FCT key, the PROGRAM DEFAULTS soft key, and
then the BLK FORM soft key. This definition is needed for the
TNC’s graphic simulation feature. The sides of the workpiece blank
lie parallel to the X, Y and Z axes and can be up to 100 000 mm
long. The workpiece blank is defined by two of its corner points:
MIN point G30: the smallest X, Y and Z coordinates of the blank
form, entered as absolute values
MAX point G31: the largest X, Y and Z coordinates of the blank
form, entered as absolute or incremental values
You only need to define the workpiece blank if you
wish to run a graphic test for the program!