so I'll just weld a couple restraining bolts to restrict the lateral expansion.
I can't find a good picture, but the charge air cooler tubes on a Cummins QSK19 use two pieces of flat stock at tube connections. There is a bung welded onto the pipe, and the flat stock bolted to one side, and a slotted hole on the other end of the flat stock to allow expansion/contraction. Without it, the rubber hose connections would fail pretty much every time under the heat/pressure of the charged air.