This is a bit of a request. All the pipes puzzles are randomly generated, so this isn’t so much a walkthrough as it is a bunch of examples. Some of these I just did from beginning to end. When that didn’t seem to work, you want to go from the obsolutes to the relatives; what I mean is to move the things that have NO choice as to their positions – straight pipes at the edge has to be parallel to the edge, corners at the corners can’t stick out. Then you work on the straight and curved pipes that attach to those, then lastly twist the rest of them into position.