Aluminum Fuel Tank Fitting Reinforcement

[Bob K.]

I'm designing and building a 75 gallon aluminum fuel transfer tank for gasoline. The tank will be made of 5052 3/16" aluminum. There will be two 2" NPT female fittings on the top for the cap and for the gas pump. There will be one baffle welded inside. Tank will be 48" long by 24" wide at the top. The tank will be pressure tested for any leaks. I was wondering if anyone who has built one of these tanks had reinforced the 2" fittings inside the tank so the pump could not cause flexing of the top when it was leaned on. I was considering tig welding a round doubler plate on the interior of the tank around each of the fitting openings. I'm curious to hear how other people have done it.

[MMW]

It won't hurt to add a doubler. Are you using plain couplings or a weld in tank bung? Bungs by design add strength.

https://fueltankparts.com/products/s...SABEgJ1o_D_BwE

[Bob K.]

Hi, the tank will use billet machined weld-in tank bungs. They are thicker and more substantial than the stamped versions.

[Electric4Life]

My vote would be to reinforce the area on the exterior of the tank at the pump location.
If the doubler or the bung fails, seeing the failure and having access to make the repair from the outside would probably make someone else's life a whole lot easier in the future.
A well shaped doubler with sound welds should not be a deal breaker for the end user, unless, like some out there, when function follows form then by all means dont worry about repairs and double that ***** on the inside.

[ryanjones2150]

I vote for the over-engineered route as well. But that’s how I roll.