A key part of the reliable operation of large, long distance crude oil transportation pipelines is the cleaning of the internal wall of the pipe itself, as well as the removal of settled solids. These substances, if not properly dealt with, can lead to the subsequent fractures of the pipe wall in the affected areas and costly environmental leakage. If fractures do not readily occur, the accumulated solids will inevitably create flow assurance problems within the pipeline by reducing the working volume of the pipeline, or even blocking the line altogether. These obstructions typically occur where the internal line velocities are reduced due to pressure drops across elbows and valves, or where due to topographical changes the solids are able to separate because of their differing density as compared to the crude oil.