You can create your own bolt symbols in Symbol Editor and use them in drawings. You only need to create bolt symbols if you need different bolt symbols than the ones that you can find in Tekla Structures.
Save the symbol file ud_bolts.sym in the symbol folder (usually the folder ..\Tekla Structures\<version>\environments\common\symbols\ ).
Open Microsoft Notepad, or any text editor.
Create a text file consisting of lines in three columns:
The first column contains the bolt assembly standard.
The second contains the bolt diameter.
The third column contains the name of the symbol file and the symbol number, separated with the @ character.
Example of file contents:
7990 24 ud_bolts@1
7990 25 ud_bolts@2
Tekla Structures uses the user-defined symbol for bolts in drawings that have the standard and diameter you define in this text file.
Save the file with the name bolt_symbol_table.txt.
Set the name of the file as a value for the advanced option XS_USER_DEFINED_BOLT_SYMBOL_TABLE in File menu > Settings > Advanced options > Marking: Bolts as follows: