Fundamentals
Application
Adaptive Feed Control (AFC) saves time when processing NC programs and reduces wear on the machine. The control regulates the contouring feed rate during program run depending on the spindle power. In addition, the control responds to overloading of the spindle.
Related topics
- Tables related to AFC
Requirements
- Adaptive Feed Contr. (#45 / #2-31-1) software option
- Enabled by the machine manufacturer
The machine manufacturer uses the optional machine parameter Enable (no. 120001) to define whether you can use AFC.
Description of function
To regulate the feed rate during program run with AFC:
- Define basic settings for AFC in the AFC.tab table
- Define settings for AFC for each tool in the tool management
- Define AFC in the NC program
- Define AFC in the Program Run operating mode with the AFCtoggle switch.
- Prior to automatic control, determine the reference spindle power with a teach-in cut
If AFC is active in the teach-in cut or in control mode, the control displays an icon in the Positions workspace.
Detailed information about the function is provided by the control on the AFC tab of the Status workspace.
Benefits of AFC
Adaptive feed control (AFC) has the following advantages:
- Optimization of machining time
By controlling the feed rate, the control tries to maintain the previously recorded maximum spindle power or the reference power specified in the tool table (AFC-LOAD column) during the entire machining time. It shortens the machining time by increasing the feed rate in machining zones with little material removal.
- Tool monitoring
If the spindle power exceeds the taught-in or specified maximum value, the control reduces the feed until the reference spindle power is reached. If the minimum feed rate is exceeded, the control executes a shutdown response. AFC can also use the spindle power to monitor the tool for wear and breakage without changing the feed rate.
- Protection of the machine's mechanical elements
Timely feed rate reduction and shutdown reactions help to avoid machine overload.
Tables related to AFC
The control offers the following tables in conjunction with AFC:
- AFC.tab
In the AFC.tab table, you define the feed-rate control settings to be used by the control. This table must be saved in the TNC:\table directory.
- *.H.AFC.DEP
With a teach-in cut, the control at first copies the basic settings for each machining step, as defined in the AFC.TAB table, to a file called <name>.H.AFC.DEP. The string <name> is identical to the name of the NC program for which you have recorded the teach-in cut. In addition, the control measures the maximum spindle power consumed during the teach-in cut and saves this value to the table.
- *.H.AFC2.DEP
During a teach-in cut, the control stores information for each machining step in the <name>.H.AFC2.DEP file. The string <name> is identical to the name of the NC program for which you are perfoming the teach-in cut.
In control mode, the control updates the data in this table and performs evaluations.
You can open and, if necessary, edit the tables for AFC during program run. The control provides only the tables of the active NC program.
Notes
- If the feed rate is about to fall below the FMIN value, stop the machining operation (instead of deactivating the AFC function)
- Define the overload response for cases in which the feed rate falls below the FMIN value
- If Adaptive Feed Control is active in Control mode, the control executes a shutdown response independent of the programmed overload response.
- If, with the reference spindle load, the value falls below the minimum feed factor
The control executes the shutdown response from the OVLD column of the AFC.tab table.
- If the programmed feed rate falls below the 30% threshold
The control executes an NC stop.
- Adaptive Feed Control is not intended for tools with diameters less than 5 mm. If the rated power consumption of the spindle is very high, the limit diameter of the tool may be larger.
- Do not work with Adaptive Feed Control in operations in which the feed rate and spindle speed must be adapted to each other, such as tapping.
- In NC blocks containing FMAX, the adaptive feed control is not active.
- In the settings of the Files operating mode, you can specify whether the control displays dependent files in the file management.