FEA Assessment of a Thin-Walled Cylindrical Asset During Lift, Skewing, and Set-Down

Project context
A thin-walled cylindrical asset required lifting from a horizontal position, skewed slightly during rotation, and set down onto temporary supports prior to final installation.

The asset was designed strictly for pressure and operational loads, with no allowance for:

• Ovalisation under self-weight

• Local bending during skewed lift

• Temporary support eccentricities during set-down

Why FEA was essential
Hand calculations could not credibly assess:

• Shell ovalisation limits under transient load cases

• Buckling interaction with local bending

• Strain accumulation during staged operations

Equitus FEA scope

• Shell-based nonlinear FEA including:

  • Geometric nonlinearity

  • Local imperfections consistent with fabrication tolerances

• Simulation of:

  • Horizontal lift

  • Skewed rotation

  • Temporary set-down on discrete supports

• Assessment against strain-based acceptance criteria

Outcome

• Defined a safe operational envelope for lift and rotation

• Demonstrated acceptable ovalisation without permanent deformation

• Avoided unnecessary stiffening rings that would have increased mass and cost

• Provided Mammoet with quantified confidence, not assumptions