API Std 650 welded steel storage tanks out-of-service supplementary drains

Static storage loss is also known as "small breathing" consumption. The rise and fall of the temperature in the API Std 650 welded steel storage tanks leads to the increase and decrease of the pressure in the tank, which makes the mixed oil gas discharged from the tank, and the external air is sucked into the tank, resulting in the oil consumption. Fluid level loss is also called "big breathing" loss. It is the oil consumption caused by the change of gas space volume in the API Std 650 welded steel storage tanks during the oil receiving and sending operation, which causes the mixed oil gas to be discharged out of the tank, and the external air is sucked into the tank, resulting in the oil consumption due to the change of liquid level height.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.This specification, in conjunction with API 650 Standard, prescribes minimum standards for the API Std 650 welded steel storage tanks design, supply fabrication, erection, and testing of field erected welded steel storage tanks complete with accessories as specified herein and as shown on attached datasheets and/or drawings.Service concept: first time to understand customer needs, first time to solve customer worriesVision: to be the leading steel materials supplier in the worldWorking principles: Keep promises; Spare no efforts; Be practical and innovative; Pursue excellenceTalent concept: build a team with a dream and complete a dream with a team!Family culture: we rely on the principles of equality, trust, appreciation and family love to form a harmonious and warm family!The high strength API Std 650 welded steel storage tanks low alloy steel, which is shorten as HSLA steel, is one of our main products. We have professional team to serve you. For any demands or questions about HSLA steel, for example, ASTM A572 grade 50 chemical composition, difference between S355JR and S355J2, mechanical properties of API Std 650 welded steel storage tanks ST52 steel, Q345B tensile strength, Q345D steel ASTM equivalent, HSLA steel price etc. , please do not hesitate to contact us and consult.

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