If it is for the purpose of joining them I would say no to the boolean. You will never really see it from the the shot distances you are most likely going to use for the scene.

If it is to put a gap that the pipes run into I would also say skip it. You can always just put a small flat black texture around those pipes and from a distance it will give the illusion of a gap.

You can also build a flange around the pipe that butts up against the other part. Here is the idea and you could also add bump mapped or actual rivet details...