Erection requirements for API 650 insulated tanks

The mechanical seal of floating roof API 650 insulated tanks relies on mechanical force to press the sealing steel plate tightly against the tank wall, so that it can slide on the tank wall and avoid gap as far as possible. However, mechanical seal has high requirements for the geometry of storage tank and poor adaptability, so mechanical seal is rarely used in newly built floating roof API 650 insulated tanks.In this project, an elemental area of tank wall used is constructed of ASTM A442 Grade 55 steel plate subjected to a meridional unit force, T1, of 4000 lbf/in.2 tension and a latitudinal unit force, T2, of 5060 lbf/in.2 compression. The meridional radius of curvature, R1, is 75 in., and the length of the normal from the surface to the axis of revolution, R2, is 300 in. The joints in the wall are of double-welded butt-joint construction with a tensile efficiency of 85%. A corrosion allowance of 1/16 in. is required.
The problem in this example is to graphically find the minimum thickness of tank wall required for the given conditions (see 5.10.3.3).
Solution: As determined from Table 5-1, the maximum allowable tensile stress value, Sts, for ASTM A442 Grade 55 steel plate in simple tension is 16,500 lbf/in.2. Since the compressive stress is latitudinal, the governing value of R in this situation is R1, or 75 in.API 650 external floating roof storage tanks are generally called external floating roof API 650 insulated tanks tanks, which means that the storage tanks are externally open tanks without a dome design, and are equipped with vertical floating roofs. API 650 external floating roof storage tanks are usually used for large More than 20,000 cubic meters of open steel API 650 insulated tanks storage tanks for storing volatile petroleum products such as crude oil, gasoline, kerosene, etc.The company focuses on quality building, continuously create greatest value for customers, and has achieved good economic and social benefits. With strong financial strength, advanced management experience, perfect sales services, strict quality purchase management system and science overall marketing means. We are willing to go hand in hand with you for common development. To be the best service provider for iron & steel products globally is our goal.For ASTM A573 Grade 70/A573 Gr.70 carbon manganese silicon steel plates, our company would issue the original mill test certificate API 650 insulated tanks EN 10204 3.1 for clients when arrange delivery, so that clients can trace the A573 Gr.70 plates origin easily.