To Merge Drawings
1. Open a drawing.
2. Click the Layout > Import Drawing/Data. The Open dialog box opens.
3. Select the source file to merge into the current drawing. When you select a file, the source file is merged into the current (target) file.
4. Select additional source files to be merged, one at a time, to add additional sheets to the current drawing.
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Merging removes the source file from memory. If you previously saved the source file to disk, it is removed from the session but still exists on disk.
When you merge two drawings that have different symbols, and if the symbols have the same name, then these symbols are saved as different symbol instances with the same name in the symbol gallery. For example, if you merge two drawings that have different symbols, both named abc, then these symbol instances are saved as abc and abc(2) in the symbol gallery.