API Std 650 flat-bottom tanks platforms, walkways, and stairways

Under the same sealing effect, the internal floating roof tank of API 650 oil storage tank can further reduce the evaporation loss compared with the API Std 650 flat-bottom tanks External floating roof tank. This is due to the shielding of the fixed roof and the gas layer between the fixed roof and the internal floating plate, which has more significant heat insulation effect than the double disc floating roof of the API Std 650 flat-bottom tanks external floating roof tank.

API Std 650 flat-bottom tanks Nondestructive testing is a technical means to detect the weld defects of large vertical tank and judge whether the weld is qualified by using the characteristics of sound, light, magnetism and electricity without damaging the tested object. Common nondestructive testing methods: ultrasonic testing (UT), magnetic particle testing (MT), liquid penetrant testing (PT) and X-ray testing (RT).

In this project, an elemental area of API 620 oil storage tank wall is constructed of ASTM A516 Grade 55 steel plate subjected to a meridional unit force, T1, of 2620 lbf/in. tension and a latitudinal unit force, T2, of 2880 lbf/in. compression. The meridional radius of curvature, R1, is 132 in., and the length of the normal from the surface to the axis of revolution, R2, is 409 in. The joints in the wall are spot-radiographed, double-welded butt joints, and no corrosion allowance is required.
The problem in this example is to graphically find the minimum thickness of tank wall required for the given conditions (see API 620 tank standard 5.10.3.3).
Solution: As determined from Table 5-1, the maximum, allowable tensile stress value, Sts, for ASTM A516 Grade 55 steel plate in simple tension is 16,500 lbf/in.2. Since the compressive stress is latitudinal, the governing value of R for this situation is R1, or 132 in.

After more than 20 years of ups and downs in the steel industry, BBN company's customers have covered South America, North America, Europe, Africa, Southeast Asia and the Middle East and other countries and regions. We treat every customer who inquires with us sincerely, whether you cooperate with us or not, we will provide you with the best quality steel solutions. Our company team also support the online customer service.

Our company's logistics breaks through the perspective that the center of transportation service is ability, and emphasizes that the purpose of transportation service is customer first. Customer demand determines the content and mode of transportation service, while production is often small batch, diversified and consumer demand tends to be diversified. In the case of personalization, our logistics service also provides personalized service projects.

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