NuVision Engineering (NVE) performed structural component evaluations in accordance with ASD, ANSI/AISC N690 and/or ASME Section III, Subsection NF, for types of loading including normal, upset (seismic) faulted (LOCA) conditions. The evaluation may be performed by using a finite element analysis to determine individual loads and stresses within the members.  

The ANSYS model is composed of several components. These consist of the vertical duct, coupling #1, transition duct, coupling #2, plenum assembly and missile shield. 

Re-qualification of existing piping: NVE analyzed piping and pipe supports for safety-related piping in parts of multiple nuclear plants. The adequacy of the piping and supports under seismic loading had been questioned by the NRC. NuVision Engineering personnel used NUPIPE and ANSYS software at the customer site to requalify the piping and supports and in some cases to redesign and add supports to correct errors made in the original design basis.

Structural evaluation of integrated head non-pressure boundary components: NuVision Engineering performed structural evaluations in accordance with ANSI/AISC N690 or ASME Section III, Subsection NF, of the following ESS components for normal, upset and faulted operating conditions:

• Shroud bolts between outer shroud and RVH
• Outer shroud flange, cylinder, top plate and lifting lugs
• Inner shroud cover plate and bolts
• Lifting links and pins
• Ring girder, connections and reinforcements
• Work platform and supports
• Cable platform and supports
• Cable bridges, cable trays and supports
• CEDM ventilation ducts and headers supported by the outer shroud
• Upper duct assemblies mounted on the missile shield