220ft diameter API 650 ground supported liquid storage tanks

The cone slope of the completed API 650 ground supported liquid storage tanks foundation is 15/1000 for the general foundation and less than 35/1000 for the soft foundation. After the foundation settlement of the storage tank is basically stable, the surface slope must be greater than eight thousandths. The edge of the tank bottom should be more than 0.3 meters higher than the surrounding ground. Above the ground, the tank bottom leakage detection tube should be drawn from the foundation sand cushion and cross the foundation ring wall or the slope protection surface. The circumferential distance should be less than 20 meters, and each API 650 ground supported liquid storage tanks should have at least 4 detection tubes.

When as-rolled plate material complies with impact test requirements as specified here, the material need not be normalized. If, as with ASTM A516, the specification prohibits impact test without normalizing but otherwise permits as-rolled plates, the API 620 welded storage tanks material may be ordered in accordance with the above provision and identified as “MOD” for this API modification.

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