Our Work
Three large blended bitumen transfer pumps (220G-367A/B/C) were experiencing significant vibration on start-up leading to repeat seal failure. This reduced the transfer capacity out of the tank farm and represented a significant production risk. Alongside ongoing modifications to pump foundation, GN2 was requested to analyze and evaluate the vibrations in the surrounding piping.
GN2 completed a field walkdown of the site and collected vibrational data at key locations on the discharge piping and supporting structure. A pipe stress model was then developed in CAESAR II and dynamic analyses were performed to model the transient start-up period. Once the model had been validated, multiple structural support modification options were developed and presented. A detailed structural engineering package was then developed for construction in the field.
A time-history analysis was used to simulate the complete start-up of each of the pumps. This model needed to be refined until it matched the recorded displacement data collected in the field. This allowed the determination of piping stresses in the system as well as cyclical fatigue stresses in the pump nozzles. Transient hydraulic analyses were also performed in AFT Impulse to provide a secondary verification for the start-up forces.
In addition, the area surrounding the pumps was very congested and there were multiple other construction limitations. GN2 was able to devise a practical, fit-for-purpose design in order to achieve the necessary structural reinforcement.