CUTTINGS TRANSPORTATION MODELING IN INCLINED AND HORIZONTAL DRILLING

Abstract

Efficient cuttings transport is very important for obtaining an effective drilling operation. In inclined and horizontal drilling, if we could ensure a good hole cleaning of the wellbore from the cuttings, we can avoid other drilling problems and successfully drill it to the designed depth with minimal time. Despite the long history of drilling inclined and horizontal wells there is a very small number of works devoted to this subject. The article explores the impact of various drilling parameters, and how they affect the required flow rate by modeling. The article analyzes two models developed empirically, namely Larsen model and Rubiandini model. Two simulation scenаrios of a well drilled in offshore Vietnam have been considered. The calculations based on two empirical models showed the same trend for required cuttings transport flow velocity and flow rate when drilling parameters, such as mud weight, rate of penetration, mud rhelogy varied. For vertical and inclined cases, we observe that both Larsen model and Rubiandini model predict flow rates that are close to flow rates typical in operation. For the horizontal case, the predicted flow rates don’t seem to coincide with flow rates in operation. In the conclusion, several recommendations on achieving better cuttings transport and hole cleaning are listed.