2H Offshore has completed drilling riser structural damping tests and developed a new model to improve drilling and conductor fatigue analysis results.
As part of our continued focus on technology leadership, 2H has developed and validated a new damping model for drilling risers and conductors that more accurately captures amplitude dependent structural damping. The model can be used to minimise conservatism in drilling riser and conductor fatigue calculations, which is important for confirming that the riser and wellhead system can be operated in a safe and prudent manner.
The drilling riser structural damping tests carried out by 2H as part of Deepstar® [Reference: ISOPE 2012-TPC-0149] took place in Fourchon in 2011. The tests measured significant structural damping in buoyant joints, as high as 2.5% to 3%. Typical steel pipe damping is around 0.3%. The damping was also found to increase with increasing test amplitudes. Typical drilling riser damping is modelled using a single damping value, which does not capture the amplitude dependency.