ISO 630 Gr E355C plates API 650 unanchored flat-bottom tank

When roof plates, knuckle plates, compression rings, and manways and nozzles including reinforcement are primarily subjected to atmospheric temperature, the rules in API 620 oil tank standard Q.2.3 shall govern.
Large Welded storage tanks Secondary Components
In general, secondary components include those components that will not be stressed to a significant level by the refrigerated liquid, those whose failure will not result in leakage of the liquid being stored, those exposed to product vapors, and those that have a design metal temperature of –60°F or higher.

Corrosion allowance, if specified, shall be added to calculated API 650 tanks shell and self-supporting roof thicknesses; to minimum nominal thicknesses of bottom and supported API 650 unanchored flat-bottom tank roof plates; to nozzles and manholes; and to all exposed surfaces of internal structural members and non-removable internals.

The Indian customer purchased our A516 Gr 70 pressure vessel steel plates to make tanks. They have very strict requirement for raw materials quality. For the A516 Gr 70 pressure vessel steel plates, they asked for Normalizing, 0℃ impact, A578 UT test, PWHT and so on tests, our Q/C department witness the production process with the technician from the customer company together. Meanwhile, we arrange BV inspection to check the quantity, spray mark, stamp on the A516 Gr 70 pressure vessel steel plates, and so on.

Prefabrication requirements of API 650 unanchored flat-bottom tank, large vertical storage tank wall panels:
1. The prefabrication of wall panel shall be processed in strict accordance with the requirements of the drawings, and inspection records shall be made.
2. After the wall panel is rolled, it should be placed on the platform for inspection with a template. In the vertical direction, use a straight-line template to check, the gap should not be greater than 2 mm, and in the horizontal direction, use an arc-shaped template to check, and the interval should not be greater than 4 mm.
3. When wall panels are rounded, attention should be paid to prevent irreversible plastic deformation caused by external forces. After rolling, it should be placed on the platform for inspection, and then placed on the prepared mold.

After sales service support personnel pay attention to commitment in their work. In the process of people to people communication, mutual trust is an important factor for the long-term and stable communication. After sales service personnel must do what they say in the process of communication with customers.