Finite Element Calculation of an Agitator Support Attached to a Storage Tank

Finite Element Analysis of a load bearing support clip welded to the second shell course of a storage tank, 11 m in diameter and 13.8 m high, designed to retain a tension rod connected to an agitator assembly mounted on a nozzle. Since the original tank was designed in 1971 under API 650 rules, which do not cover this type of localized attachment loading, the new condition was verified using ASME VIII Division 2 rules and FEA methodology. Linearized Von Mises stresses, and triaxial stresses at the most critical points, were evaluated for membrane, local membrane, membrane plus bending, and protection against collapse criteria, under the combined operational load of the tension rod, self weight, and maximum liquid level at a specific gravity of 0.92. Results confirmed that both the shell plate and the clip components, including welds, comply with all ASME VIII Division 2 Part 5 requirements, with no significant stress increase on the tank wall and no risk of collapse or damage from the new loading condition.