Creating Solids and Surfaces from 2D - Autodesk AutoCAD 2013 Practical 3D Drafting and Design - page 119

Note
If the section is not applied correctly, that is, it is upside down or with the worked
part out, undo the command and apply the MIRROR command. Then apply
SWEEP .
Exercise 4.6
The piping systems can be easily created with the SWEEP command. To do so, follow
these steps:
1. Open the drawing A3D_04_06.DWG . This drawing already contains a 3D
polyline that will be used to create a set of pipes like those used in indus-
trial facilities.
2. To define the section, create three circles, set the radius as 0.5 and sep-
arated them by 0.1 units in the Y direction.