Storage Tank Roof Access 1

[texasmike45]

API requires a qualified person inspects the tank roof to confirm that it is structurally sound and will support the weight of the workers and equipment.

My questions are;

What methods of inspections are performed to document and confirm the structural integrity of the storage tank roof?

What type of calculations are required to confirm the minimum required roof thickness to support the weight of the workers and equipment?

How are localized areas of external or internal corrosion addressed in relationship to the calculated minimum required roof thickness?

Thanks Mike Whitehurst

 

[BlackOilsandBitumen]

Mike,

Just did something similar myself. I used a laser scanner placed inside the tank to collect cloud data. I then had this analysed and used to produce a drawing of the roof truss structure. (it was acurate enough that they could determine beam dimensions and thicknesses). This data was then used to assess the structure in Strand 7 software (finite element analysis).

This was to prove that the structure could support the dead weight load, wind load, live load etc as per API 650 and NACE 7.

I then inserted a GoPro camera set to take a photo every second on a pole through nozzles at verious points in the roof to show that no significant corrosion exsisted and to collect photographic evidence.

As for the plate thickness U/T then API 653 specifies a minimum. I was more concenrned about the roof truss structure.

 

[Ganotec]

BlackOilsandBitumen,
Can you give more information on what laser scanner and program you have used to produce the 3D drawings?

Thanks in advance,

Ganotec