The Stovebolt Site Forums The Shop Area General Truck Talk Question On Fittings ???

I disagree with the statement that the AN size is inside diameter of the tubing, it's outside diameter. There are all different sizes of tubing wall thicknesses but you use the same size nut for all of them in a size range. It's been awhile but common thicknesses are .032 .049 .062 and in bigger tubing .125 for really high pressure. I hope that made sense, for example,1/2 inch tubing will measure 1/2 inch outside diameter no matter what wall thickness you get, the inside diameter varies. The aircraft industry uses lots of AN fittings in aluminum, I used lots in the oil industry in stainless. Dave