You can share equations and global variables among models.
You can export all equations or selected equations to a text file, and import all equations or selected equations from a text file. The text file can be shared with other parts and assemblies that use the same global variables and equations.
You can create permanent links with text files using the Link to external file, so that changes to the text file are propagated to the model.
The Link to external file always creates a link with the external file. The Export and Import processes include options for one-time exports and imports without a link.