Importing a GiD file

Choose Open from the Files menu. Select the file where the first part, created in section Creating a component part, was saved. Click Open.
Choose Files->Import->Insert GiD model from the menu. Select the file where the second part, created in section Creating the T junction, was saved. Click Open.
The T junction appears. Bear in mind that the lines which define the end of the first pipe (background) of the T junction, and which have been imported, were already present in the first file. Notice that the lines are duplicated. This overlapping will be remedied by collapsing the lines.
Check duplicated lines with the tool View->Higher entities->Lines

Importing the T junction file to the main file. Some entities are duplicated and must be collapsed.

Choose the option Geometry->Edit->Collapse->Lines. Select the overlapping lines and press ESC. It doesn't matter if do you select some other lines more, because they won't be collapsed with the small automatic tolerance.

Higherentities drawn by colors after the collapse.

GiD user manual