API Std 650 flat-bottom tanks dimensional tolerances

Allowable Design Stresses
The maximum allowable design stresses for the API Std 650 flat-bottom tanks materials outlined in Q.2.1 shall be in accordance with Table Q-3.The values for the allowable design tensile stress given in Table Q-3 for materials other than bolting steel are the lesser of (a) 331/3% of the specified minimum ultimate tensile strength for the material or (b) 662/3% of the specified minimum yield strength, but they are 75% of the specified minimum yield strength for the stainless steel, nickel alloy, and aluminum materials. Allowable test stresses are based on the limitation of API 620 oil tank storage standard Q.8.1.3.

These API 650 documents will define the bases of design, operation, inspection, tests, examinations, and maintenance of an API Std 650 flat-bottom tanks industrial facility. Bidders will study and analyze all this API 650 documentation, both during the preparation of the quotation and during the execution of each project activity.

In year 2015, we ship 750 tons H beam to Pakistan for our old customer for building use. Because of urgent demand, the H beams are partial shipment by bulk vessel. Due to strong support of our customer, we also export many C channel steel, API Std 650 flat-bottom tanks I beam and other profile steel to local market.

Deformation of the welding seam of the API Std 650 flat-bottom tanks is a common quality problem during the actual use of the API Std 650 flat-bottom tanks, which easily causes the tank body to leak and affects the safety of the oil storage tank. The welding seam deformation of the API Std 650 flat-bottom tanks is mainly caused by the lack of reserved welding seam gap and irregular operation. The oil storage tank has not reserved the corresponding weld gap, resulting in deeper root removal during the front welding activity. The heat output of the weld will increase under the influence of a long time, and the deformation of the weld will gradually become serious.

Relying on the background of high-quality steel resources and its own strong steel machining capabilities, BBN comany can not only supply various steel material products, such as steel coils, steel plates, API Std 650 flat-bottom tanks sheet, steel pipes, and shaped steels, but also provide a variety of steel deep processing services like cutting, welding and grinding. Through continuous technological innovation and after-sales service optimization, the company has its own world on the domestic and international steel industry stage!