API Std 650 SUG II tanks bottom joints

As we know, the vertical metal tank, API Std 650 SUG II tanks is welded by many components, and the welding quality of each component determines the later use effect of the API Std 650 SUG II tanks. Professional API Std 650 SUG II tanks manufacturers should have a set of professional skills in the welding process of API Std 650 SUG II tanks. Key points for weld inspection of vertical metal tank, API Std 650 SUG II tanks:
1. It is strictly forbidden to paint the welds before passing the inspection.
2. Visual inspection shall be carried out for welds.
3. NDT shall be carried out on the weld.

Except as permitted by API standard 620 Q.8.6, the test shall be conducted after the entire tank is complete, before the insulation is applied. Except as limited by foundation or stress conditions, the test shall consist of filling the tank with water to the design liquid level and applying an overload air pressure of 1.25 times the pressure for which the vapor space is designed. The load on the supporting foundation shall preferably not exceed the established allowable bearing value for the tank site. Where a thorough evaluation of the foundation justifies a temporary increase, the established allowable bearing may be increased for the test condition, but the increase shall be not more than 25%.

Floating roofs shall comply with API standard 650, Appendix C (Attachment 01) or with the API Std 650 SUG II tanks requirements as layed (laid )down in the national Chinese specifications SH3046-92 and GBJ128-90.