A downspout forming machine, known as rainwater downpipe roll forming machine as well, has been designed for making square or round (circle or rectangular) rainwater pipes.

A downspout has many different names as, waterspout, downpipe, drain spout, and roof drain pipe etc. According to the wiki, the downspouts are applied mainly as below:

Downspouts are usually vertical and usually extend down to ground level. The water is directed away from the building's foundation, to protect the foundations from water damage. The water is usually piped to a sewer, or let into the ground.

In the very beginning the downspouts are made of plastic, then PVC; due to the advancement of roll forming technology, people turn to roll formed pipes, and in modern times, most of the downspouts or rainspouts have been produced from pre-painted steel, galvanized steel, aluminum or copper.