Create a surface from IGS and a export a line

Hello,

I have an IGS, I want to use the upper surface as cutting tool in the middle and extract a line which has the same distribution.

I succedded to make a line (with a perpendicular surface, which is similar), however I don't know how to export it.

I attacch the IGS plus other pictures, in order to better understand the problem

Thanks a lot for any suggestion and help

Kind regards

Antonio

SolidworksAssemblies