Converting vendor specific CAD files may sometimes be a tricky thing, unless you have access to several professional CAD formats. Luckily, you can also find some dedicated CAD converters like the CrossManager that can handle many formats, including those from CATIA and Parasolid.
Open CATPART file Open X_T fileA set of 3D modeling tools
A 3D product data optimalization software
A CAD visualizaton, analyzation and translating system
A dedicated CAD converter