Some time ago, I secured a 9 gallon pressure container. I have been planning to converting it into a slightly-pressurized (~ 2-5 psi, regulated) container for oil/diesel/waste cleaning solvent. (Charcoal lighter) I have figured I need four bungs - inlet, outlet, and two for a sight glass. Thought was to use mild steel, tapped for 1/4 inch national pipe thread, for all save the inlet. That one needs to be larger. How much larger, and what thread - I'm not decided. I know all of these fittings musn't leak. Comments desired.
I've so far managed to avoid having to drill into a pressurized tank. I'm not that confident in my welding skills. It would be prudent to included a pressure relief valve though. I know you already have the tank, but if you consider a small gas hot water tank you'll have everything you need. Since I don't move mine in order use it I chose a larger tank. It has the same footprint as a smaller one and provides plenty of storage. 3 top holes: Former water out hole serves as pressure in Former water in hole serves as oil out (already has a dip tube!) Anode hole serves as fill hole/pressure relief valve Side holes: Former pressure relief valve hole is upper site tube hole Gas controller hole is lower site tube hole It even has a ready made drain valve to tap off settled water. You can use it as-is. No need to strip it. Pete
