Use the Change number commands to change the existing part, assembly, multi-position, or family numbers into something you have defined yourself. These commands do not change the numbering series of parts. To prevent drawing, modeling, and fabrication errors, Tekla Structures does not allow you to use identical numbers for two different assemblies or parts.

1. On the Drawings & reports tab, click Change number and select one of the following commands:
   • Change part number
   • Change assembly number
   • Change part multinumber
   • Change assembly multinumber
   • Change family number

   The corresponding dialog box appears. For example, if you select the Change assembly number command, the Assign Assembly Number dialog box appears.

2. Select a part in the model.
3. In the dialog box that appeared (for example Assign Assembly Number), click Get to view the current numbering properties of the part.
4. Enter the numbering properties you want to use for this part.

   Note that the position numbers you enter here are not absolute numbers. For example, if the start number of the series is 100, the position numbers refer to numbers in that series. Therefore, position number 1 is actually 100, position number 2 is 101, position number 3 is 102, and so on.

5. If you are changing the assembly number of selected parts, ensure that the Assign to option is set to Selected objects only.

   Otherwise, all parts with the same original number will be renumbered.

6. Click Assign to change the number.

   If the number you specified is already in use, Tekla Structures displays a warning and keeps the original number.

   Tekla Structures also displays a warning if the position number is higher than the highest current number. This is for information only and the number is still changed.