SolidWorks may be able to export its own drawings / parts / assembly to other formats - including generic part files (.prt)r. It may require a special plugin though, or some kind of add-on that adds support for other CAD formats. You can also probably find some kind of CAD conversion tool that may support this conversion. The easiest way however, would be to use SolidWorks itself.
Convert SolidWorks CAD drawing to CAD 3D part or component.
We found 2 software records in the database related to .slddrw to .prt file format conversion.
Microsoft Windows software - convert slddrw to prt on Windows
A CAD converter with huge format support
Convert from slddrw file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned slddrw to prt. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
A 2D and 3D CAD construction software