LABORATORY EVALUATION OF FILTERCAKE CLEANUP TECHNIQUES AND METALLIC SCREENS PLUGGING MECHANISM IN HORIZONTAL WELLS
Tests were conducted to evaluate the plugging mechanisms of metallic screens after cleaning up the filtercake developed on an unconsolidated core by two exiting drill-in fluids (DIF"s). Two simulated drill solids, clay or 75-mm reservoir sand were added as drill solids to these DIF"s. Metallic screens were used to simulate the sand control device. The DIF's tested included a sized-calcium carbonate (SCC) and a sized-salt (SS). The presence of the drill solids was found to affect the particle size distribution as well as the mean size (D50) of the particles of the bridging and weighting material (BWM) and loss control material (LCM) of the DIF"s. On the basis of the observations, it can be concluded that SCC filtercakes tended to result in minimum dislodging pressure (MDP), leading to higher regained-flow capacity and lower plugging of the screen. In contrast, SS filtercakes required high MDP, decreasing the regained-flow capacity highly and causing severe plugging of the screens.