Is it possible to assemble different meshed parts into same part in hypermesh?

I'm preparing model of a large pressure vessel. The model is done in CATIA V5R21. The problem is the CATIA file is 62mb and Hypermesh hangs to import it. I cannot reduce the file much smaller as it is already reduced from 90mb to 62mb. I'm thinking of making the vessel into two parts and meshing it separately and assembling it in hypermesh and then to volume mesh the interior. I'm going to perform a CFD analysis on this vessel which has a dia of 5400mm and length of 17000mm. Is it possible to do this way in Hypermesh?.

Thanking YOU

Sriram