Structural Analysis of Compressor Skid Nozzles

An FEA structural analysis on compressor skid nozzles was performed for a manufacturer who was developing the skid for the Wheatstone Project LNG Plant, located near Onslow, Australia. The equipment included motor, compressor, instrumentation and controls. We were asked to determine the loads (and allowable loads) at the pipe connections where they exit the skid, taking into consideration deadweight, seismic, wind, and pressure loads.

Stresses in structural members, equipment and individual components are not considered in this evaluation. In addition, anchor bolt calculations and sizing are not considered here. To facilitate the analyses, a finite element model of the base skid structure was created using ANSYS. Equipment mounted to the skid was modeled using lumped mass elements at the corresponding center-of-gravity (CG) locations. 

The masses were attached to the skid or compressor table structure using constraint equations between equipment mounting locations and the lumped masses corresponding to the equipment CG locations. Fluid in the intercooler and oil reservoir was represented using mass elements that were attached to the containment structure to account for seismic loading.

O’Donnell Consulting Performs Engineering Design and Analysis on Vessels, Skids & Other Process Equipment.