Click Open 
.
In the dialog box, select IGES (*.igs; *.iges) in Files of type.
Click Options to set the import options.
In the Import Options dialog box, click General.
Select Surface/solid entities and Try forming solid(s).
You can import files to the SolidWorks software from other applications. The geometry and structure of the resulting SolidWorks model matches that of the model in the source application. In this lesson, you import surfaces from an IGES file. Because the surfaces form a closed volume, you can use them to create a base feature.
Click Open .
In the dialog box, select IGES (*.igs; *.iges) in Files of type.
Click Options to set the import options.
In the Import Options dialog box, click General.
Select Surface/solid entities and Try forming solid(s).
The SolidWorks software attempts to form solids from the surface or solid entities in the imported file.
Click OK to accept the other default settings.
Browse to <install_dir>\samples\tutorial\importexport, select gasket.igs, and click Open.
If prompted to run Import Diagnostics, click No.
The SolidWorks software forms a base feature from the imported surfaces. The imported body appears in the graphics area, and Imported1 appears in the FeatureManager design tree.
You can use FeatureWorks
to recognize imported features as editable SolidWorks features. For example,
using FeatureWorks, you could recognize the Imported1
feature as an extrude feature with hole features.
