FANUC tool life management: relating group numbers, tool numbers, offsets and remaining life
The 30i/31i/32i-B descriptions manual distinguishes life-management groups, physical tools and offset data. A remaining-life calculation separates advance warning from end of life and helps investigate dimensional changes after a replacement tool takes over.
Contents
If a replacement tool is loaded successfully but part dimensions change, checking the life counter alone is insufficient. Tool life management also depends on the correspondence between tools in a group and their offset data. A completed tool change does not establish that these data are correct.
Document scope and data structure
Section 8.31, printed pages 297–298, of the public mirror of the original FANUC B-64482EN/03 descriptions manual covers the 30i-B, 31i-B5, 31i-B and 32i-B. It describes life-management data including group number, life value, tool number and offset designation information. The function and tool-change type must match the particular machine configuration; no parameter-activation method is provided here.
| Data | Question to resolve |
|---|---|
| Tool group number | Which group of verified equivalent tools can be selected for this operation? |
| Actual tool number | Which specific tool in the group is currently in use? |
| Offset designation information | Do the called length, radius and other values belong to this actual tool? |
| Life value and counter | Is life managed by time or count, and what has accumulated? |
The exact offset fields depend on the lathe or machining-center system and tool-change type. A group number cannot simply be treated as a tool or offset number.
Remaining life and advance warning are not end of life
The manual also describes advance-warning capabilities of Tool Life Management B. Arithmetically, remaining life＝set life−current count. Whether a warning output exists also depends on the relevant function, threshold and machine handling.
For example, if a group is count-managed with a life value of 100 and a current count of 92, the remainder is 8. With a warning threshold of 10, the warning conditions warrant checking. This does not mean the tool has reached 100 uses, nor does the arithmetic alone prove that the warning signal has actually been output. This is a logic check, not a recommended life setting.
Investigating a problem after a replacement tool takes over
- Record the actual tool numbers before and after the change. Confirm that the intended replacement is used, rather than relying on an unchanged group number.
- Check the corresponding measurements, offset designations and tool specifications. In particular, check whether new-tool measurements were mistakenly written into the old tool's entry.
- Compare dimensional changes for the same program and workpiece, then examine workholding, actual tool differences and process conditions.
A counter does not directly measure wear or detect a chipped edge. Tools in the same group must first meet process substitution requirements; the life strategy then determines when one takes over. Also verify the machine response when the entire group reaches end of life, not only the transition from the first tool to the second. Return to the OPTION resources.