29. Jul 2019

Sand control: Comprehensive study on erosion behavior

Within the scope of a comprehensive study undertaken by a large exploration and production company, the erosion behavior of common filter media in pipelines was investigated. GKD – GEBR. KUFFERATH AG performed supplementary CFD modeling of flow paths and pore velocity distribution. During this work, it was also demonstrated that the flow-dependent multiplier at maximum velocity is greater than previously assumed by a factor of 63. The RDTW mesh from GKD is capable of permanently handling this velocity. Thanks to its greater design-based volume porosity, it reduces the flow rate by around 30 percent in comparison with twilled dutch weave, while maintaining the same aperture.

A large exploration and production company launched an experimental erosion study to identify the flow parameters which cause destruction of the filtration mesh in pipes. The aim was to determine and then describe the relationship between the service life of the pipes and the flow rates in a formula. The combination of empirical data and experimental work with CFD simulations allowed findings from the field and the laboratory to be supplemented with statements on a flow-optimized mesh design. The laboratory test impressively demonstrated that smooth dutch weaves and twilled dutch weaves are not the best choice for meeting the requirements of oil fields. It also became clear that the loss of mass only occurred in the areas of the holes in the perforated plate system. Taking into account the correlation between a larger pore size and loss of mass, a value calculated by GKD was derived as a new basic parameter for the erosion prediction formula. Based on CFD simulations, this enables GKD to bindingly state the inflow velocity and angle at which the particles hit the wire of the filter medium. GKD was also able to demonstrate that the maximum pore velocity at maximum inflow can be determined – even for multi-ply designs – from the inflow velocity using a factor of 63. The change in effective porosity of the filter media to be anticipated in the field can then also be read off. Cleaned, annealed, and fully camera-inspected RDTW meshes proved particularly efficient within the scope of the study. They impress with their high porosity and low pore velocity, while at the same time guaranteeing the most efficient production. Thanks to the enormous flexibility in terms of their design, they can be optimized for erosion performance, price, or ruggedness. As such, they open up new prospects for economically sustainable exploration and production of crude oil and natural gas.