A662 Gr C plates API Std 650 mechanically-anchored tanks

The ring of API Std 650 mechanically-anchored tanks annular plates shall have a circular outside circumference, but may have a regular polygonal shape inside the tank shell with the number of sides equal to the number of annular plates. These pieces shall be butt-welded in accordance with API Standard 620 R.7.1.1, Item b. The plates of the first shell course shall be attached to the annular bottom plates by welds as required by API Standard 620 5.9.5 except when a full penetration weld is used or required.

API 650 Tanks in which liquid fluids are stored and designed to withstand atmospheric pressure operation, less than 18 kPa, or internal pressures not exceeding the weight of the API Std 650 mechanically-anchored tanks roof, with temperatures no higher than 93, 3 C are included in the scope of this design code.

The manufacturing requirements of bottom plate of vertical metal tank, API Std 650 mechanically-anchored tanks are as follows: 1. In order to compensate welding shrinkage, the layout diameter of tank bottom is 5-2mm than the design diameter; 2. The butt joint of edge plate of tank bottom shall be machined automatically or semi-automatically; 3. The distance between any two adjacent welding joints on the tank bottom plate and the distance between the butt joint of edge plate and the longitudinal weld of bottom ring wall plate shall not be greater than 200 mm.