Abstract: A pipe elbow has a first end and a second end off parallel to the first end. An interior surface of the pipe elbow has a centerline having an arcuate portion. A circular cylindrical exterior surface portion of the pipe elbow surrounds the arcuate portion of the centerline.

Abstract: A support structure is disclosed, which includes plural cylindrical joints. Each cylindrical joint includes a cylindrical joint body having a wire channel for being passed through by a wire, a cylindrical joint head disposed on one end of the cylindrical joint body and having the wire channel, a cylindrical joint socket disposed on another end of the cylindrical joint body and having the wire channel The cylindrical joints are connected one by one by coupling the cylindrical joint to the corresponding cylindrical joint socket and are rotated along the radial direction of the cylindrical joint head.