.EXP File

File extension exp is also used for one of the default data export formats used in CATIA 3D CAD software from Dassault Systemes.

Note: It seems some older CAD software used exp extension as well for engineering drawings, but these seems to be based on ISO STEP schema which typically uses either stp or step extension.

How to open:

You should be able to work with these files using CATIA.

How to convert:

It should be possible to convert these CAD files to other formats.