HEIDENHAIN CNC Pilot 4290 - Manual (Page 69)

HEIDENHAIN CNC PILOT 4290 57
3.7 Load Monit
or
ing
3.7.4 Analyzing Reference Machining
The torque and the limit values of the selected
component are shown ”over time.” Limit values
”gray”: nonmonitored area (hiding rapid traverse
paths).
The CNC PILOT also displays the values of the cursor
position.
Selection: ”File” button (”Display and set load
parameters” dialog box).
”Analyzer (file display)” submenu:
■ ”Set cursor” pull-down menu; using the right/left
arrow key, position the cursor at the:
■ Start of file
■ Start of the next zone
■ Zone maximum
■ ”Display” menu item: Select the component from
the ”Display file” dialog box.
■ ”Setting – Zoom” menu item: Set the zoom
factor. (Small values increase the accuracy of the
display and reduce the step size of the cursor.)
The settings defined for the grid, the time reference
grid of the measured value registration and the
cursor position are shown in the line below the
graphic display (relative to the start of reference
machining). Time ”0:00.00 sec” = Start of reference
machining cycle.
Switch back to ”Edit load parameters”
3.7.5 Machining Using Load Monitoring
It is advisable to use the load-monitoring function
when - due to a dull cutting edge - a machining
process requires a considerably higher torque than
with a new cutting edge. As a rule, drives that are
subjected to considerable loads should be monitored -
usually the main spindle.
Due to the relatively small torque variations, it is
difficult to monitor machining operations with small
cutting depths.
A decrease in torque cannot be identified.
Defining the monitoring zones: The reference values for torque
depend on the maximum torque values of the zone. Therefore, lower
torque values cannot always be monitored.
Facing with constant cutting speed: The spindle is monitored as
long as the acceleration is 15% of the mean value from maximum
acceleration and maximum braking deceleration (machine parameters
811, ...). Since acceleration increases as a result of the increase in
rotational speed, the CNC PILOT usually only monitors the period after
the first cut.
Experimental values for the machining of steel
■ For longitudinal turning, ensure that the cutting depth is greater than
1 mm.
■ For recessing, ensure that the cutting depth is greater than 1 mm.
■ For hole drilling, ensure that the diameter drilled is between 6 and
10 mm.