Pipeline installation pull analysis

The purpose of this study was to determine the behaviour of a pipeline as it was installed using the bottom-tow method. This included developing a three-dimensional model using the finite element analysis package ABAQUS, and simulating the pulling of the pipe into a pre-dredged trench.

The finite element analysis accounted for the variation of the weight of the pipe during the pipe pull, as the submerged weight was considerably lower than that of the pipe on the launchway.

Included in the analysis were the effects due to tidal variation throughout the pipe pull operation, and the varying trench profile along the route.

Once the analysis had been completed, the client could see how the pipeline would behave during the pipe pull process, and could therefore conclude on the appropriate steps to follow for the actual installation.  The analysis provides an indication of pipe behaviour, and can be completed before the vessel is deployed to install the pipeline.  This can lead to considerable cost savings, by avoiding unforeseen delays due to the methodology chosen.