Experimental Study of Cuttings Transport in Coiled Tube Micro-Borehole Drilling

Abstract

This research presented an experimental study of the cuttings transport in vertical micro boreholes. The cuttings settling and transport velocities were obtained under various conditions of cuttings (size, concentration) and fluid properties (flow rate, rheology) and annulus geometry. The results showed that it is inaccurate to predict the cuttings transport velocity based on the cuttings settling velocity. The lab results were compared with a series of field tests in both vertical annulus and curved pipe.