Calculation of the hydrostatic test pressure value 2

[VladIv]

Dear Sirs! Please, be so kind to give me an advice on the question: where can I find an explanation of the item UG-99(b) of the BPVC Sec. VIII Div. 1 requirement to use the LOWEST stress ratio for calculation of the hydrostatic test pressure value? Why not the HIGHEST ratio?
Please, don`t be angry if you find mistakes in my post. My native language is Russian.

 

[Fizza453]

Lowest stress ratio is equal to allowable stress value in tension at test temperature divided by allowable stress value at design temperature. Generally it is 1 upto 250C.


Javed Nasir
Inspection Engineer
Technip-France Abu Dhabi

 

[mk3223]

For the hydrostatic test pressure, the component with the lowest stress ratio may be the weakest point of the whole vessel. And, it is to be overpressure first before all other parts.

 

[prex]

If you used the highest stress ratio, the component with the lowest one would fail.

prex
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