API 650 - APPENDIX S - JOINT EFFICIENCY 1

[mancini]

If I have to design a tank in accordance with API 650 , APPENDIX S (stainless steel tank),is it correct to consider different joint efficiencies (E) to be applied in the same shell but different shell elevations?

For instance, in order to reduce the shell thickness using E=1.0 on the lower part of the shell and using E=0.85 on the upper part of the shell.

Thanks.

 

[JoeTank]

That is not specifically addressed in API-650. You may wish to submit it as an inquiry to the API Sub Committee on Pressure Vessels and Tanks. Their web is

http://www.api.org.

Steve Braune
Tank Industry Consultants

http://www.tankindustry.com

 

[JStephen]

Normally, you'd use the same joint efficency and radiograph criteria for the whole shell.