i forgot how to model curved pipes again how did u do that hoot
Late to this question, but imo the best way is to make the pipe's path first with a curve/path, I personally use bezier.

After that make a circle curve or alternatively make a regular circle and convert to a path. (Alt C)

Now select your curve, select the curve tab in properties and choose the circle as your bevel object.

You should now have your pipe/tube/whatever.

This isn't just limit to circles, useful for various things like a rectangle belt.