I just usually generate a temporary CATProduct, insert my CATPart into it and use Sectioning tool in Assembly Design. Then you can save your section as CATPart/IGS....
As ferdo says, the assembly sectioning is CGR based, so the section isn't exact but if you set the tolerance to highest possible in tools/option then the result is good enough so the drawing will recognise the element types like circle and so on. But don't use the sections to build geometry.
Good point Azrael, its true what you said. Usually, if you have few parts to check if they clash or not with this method, you will have clash even if you have nothing in clash analyze....