API standard 650 unanchored tanks liquid penetrant examination

The working pressure of the low-pressure storage tank is greater than that of the atmospheric storage tank, but its pressure is less than 0.1MPa. API 650 petroleum storage tanks are classified according to their environment: Above-ground storage tank: refers to the bottom of the storage tank at the design elevation of API standard 650 unanchored tanks and above; the bottom of the tank is below the design elevation of +0.00 but not exceeding.

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.

Compared with other fast-moving consumer goods, steel consumption is obviously different, with a wide range of use and a long service life. Therefore, the quality and service of steel materials are particularly important. Service is always one of our top concerns, especially after-sales service. We have mature after-sales service team, and can help you solve problems professionally during application of the steel materials.

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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