Hello mvs123,

As stated in the code, the analysis of tanks 36m diameter and over in accordance with Annex P is not mandatory unless required the purchaser. I think that is fairly clear. The next point is: Does Annex P accurately compute the flexibility of the shell wall or not. I look at it this way; do the nomograms indicate the stress is outside the boundary defined by the nomograms. If it is outside the boundary, then FEA could be considered.

Other software such as NozzlePRO (available from Intergraph) could be use to refine the analysis. Alternatively, the WRC 107 Bulletin could be used to assess the stresses in the shell wall.

If you have the PV Elite programme, then it can to the WRC 107 analysis.