Features of a 210M Gallon Tank

[chicopee]

Please describe and explain two features of a 1958 #2 fuel oil tank. First is a crank mechanism at ground level with a steel cable running to the top of the tank and then penetrating thru the domed roof. Secondly is the appearance of a cylindrical vent (estimated at 12" dia.)with a protective cap mounted at the center of the domed roof.

 

[JStephen]

See the drawings at the bottom of Page 2 of this brochure for possible explanations for your crank:

http://www.rmenergy.com/literature/oilfield/staytite.pdf

The other item does indeed sound like a tank vent. It lets air in and out so that the tank doesn't develop any pressure or vacuum due to changing fluid levels or changing temperatures. The cap keeps rainwater out. It should have a screen to keep bugs and birds out. There are several variations on the design. Commonly called a mushroom vent or a free vent. Models are also made with pallets to prevent unnecessary air flow (requires the tank be designed for small pressure vacuum conditions), called conservation vents or pressure/vacuum vents. For water tanks, some models incorporate pallets to prevent vent clogging due to ice on the screens.

 

[chicopee]

Thank you for your answers JStephen.