Opening Programs And Entering - HEIDENHAIN TNC 620 User Manual

3.2

Opening programs and entering

Organization of an NC program in HEIDENHAIN
Conversational 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 in ascending sequence.
The first block of a program is identified by BEGIN PGM, 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 END PGM 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!
Define the blank: BLK FORM
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: the smallest X, Y and Z coordinates of the blank
form, entered as absolute values
MAX point: 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!
TNC 620 | User's Manual
HEIDENHAIN Conversational Programming | 5/2013
Opening programs and entering
Block
Path functions
Block number
3
3.2
Words
89