Conversion from Sketchup to CATPart is not supported yet :(

An SKP file is a three-dimensional model created by SketchUp, a 3D design program. It contains a model with wireframes, shades, edge effects, and textures.

The SKP file enables conceptual designs to be created, viewed, and shared quickly and easily. When you create a new document and save it in SketchUp the SKP file is created to store the document and its contents. SKP files can also be used to store SketchUp components. Components may be made by you or another user and can be imported into an SKP document to be inserted into your model.

CATPart is a native format developed by Dassault Systems for storing parts of the assemblies created in CATIA V5 software suite, which is extensively used in mechanical engineering including aerospace, automotive, shipbuilding and other domains.

CATPart stores geometry, structure and metadata of 3D models dedicated to single parts. Multiple CATPART files can be combined into a CATProduct assembly file.

Among CAD applications that support CATPart extension are Autodesk Inventor, Fusion 360, and 3ds Max.