Failure of Fuel oil tank Roof with Structure
Failure of Fuel oil tank Roof with Structure
(OP)
I have a case of a 32M dia x 20 M height Cone roof fuel oil tank, the roof of which collapsed. The roof alongwith the truss structure caved in. At the time of the collapse, the tank had about 2 Metres of fuel oil in it. The tank had steam coils but there wasn't any transfer from / to the tank. Apart from the roof, two shell courses have also caved into the tank pulling the connected foam piping, appertunances away from their places.
Can the forum members throw light no analysing the failure. The roof had one 8" Gooseneck vent on top with a 36" line feeding/taking out liquid to/from the tank. Storage tank flash point is >66 deg.C with a storage temperature of 90 deg.C. Tank is designed to API650. I am worried about the safety of the other three tanks which are similar.
Can the forum members throw light no analysing the failure. The roof had one 8" Gooseneck vent on top with a 36" line feeding/taking out liquid to/from the tank. Storage tank flash point is >66 deg.C with a storage temperature of 90 deg.C. Tank is designed to API650. I am worried about the safety of the other three tanks which are similar.





RE: Failure of Fuel oil tank Roof with Structure
Can you comeback with more details like was material being drawn off at time of collapse?
Had there been any problem with heating system?
Is the vent working properly?
Any signs of corrosion on the steel?
RE: Failure of Fuel oil tank Roof with Structure
I am proceeding on the basic assumption that the vent sizing could have been deficient or Vent could have been blocked or that it was a pure structural failure due to corrosion of the Structural Truss supporting the roof plates.
Can the members suggest on methods to calculate the size required for the vents. API 2000 only gives the capacities that need to be considered !
RE: Failure of Fuel oil tank Roof with Structure
Some of the ASHRAE books have duct sizing info that can be adapted to vents, but it won't technically meet API-2000.
RE: Failure of Fuel oil tank Roof with Structure
Try to be close to the tank as much as possible to see what's being done. Things get changed, especially if there is a highly visible failure.
I use to say drink coffee with the operators and keep a tight lip
RE: Failure of Fuel oil tank Roof with Structure
RE: Failure of Fuel oil tank Roof with Structure
Cheers,
gr2vessels