Joint Efficiency for Large Storage Tanks

[mecharya]

Hello,

As per Section 6 of API 650, it seems for large storage tanks joint efficiency is not considered 1.00(notations of Figure 6-1 mentioned spot radiography). Is it right?

What shall we use as joint efficiency in E.6.2.4(b) for large storage tanks? (tanks which not included in Appendix A)

Thank you in advance

Arya

 

[JStephen]

API-650 assumes a 100% joint efficiency for the standard design. This does not require full radiography except in heavier plate, and should not be confused with the requirements of ASME. (Note that allowable stresses are a lot different from ASME as well.)

Under App. A, you can use reduced or omitted radiography with lower joint efficiencies.

 

[mecharya]

Thank you for your help JStephen.