Fitness for Service of High Pressure Reactor – Schlumberger
iGET team performed structural health assessments for 6 high-pressure reactors. The reactor design consisted of multiple-layers of shrunk-fit high alloy steel and was subjected to very high (30 ksi) operating pressure cycles and temperatures of 450oF. Sharp NDE LLC performed the Non Destructive Testing to provide data on flaw sizes for these reactors.
A Finite Element Model was used to obtain stresses during the pre-stress and the operating cycles. Built ABAQUS Finite Element Solid Model consisting of inner and outer cylinders with a contact interface. Performed nonlinear stress analysis, and fatigue assessments for the pressure and thermal loads. To determine the remaining life of the vessel, S-N curve for low alloy steel from ASME Boiler and Pressure Vessels Code, 2013 Section VIII, Division 2 was used to calculate the fatigue damage during the operating regime. Total damage was computed by the cumulative sum of all damages.
Conducted risk analysis from fatigue failure per ASME Section VIII Div-2 and API 579/ASME FFS-2007 Fitness‐For‐Service (FFS) criteria. Provided engineering operations recommendations for future use of the reactor. Used ABAQUS and AutoCAD software.