Pipes is a desktop system which analyzes an Autocad drawing of a sprinkler system, checks for flaws and after these are eliminated, adds the size/diameter labels to the drawing. Tutorial: http://users.norwoodlight.com/janh/wink/autopipes-entry.htm
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.