Abstract
For the period different drilling campaigns took place at the Tapi and Auca Fields, Ecuador. A downhole monitoring pressure tool helped identify some important pressure behaviors and scenarios.
The ECD monitoring led to better wellbore cleaning, drop of mud weight detection not detected on surface and improvement of drilling operation times by deciding whether it was necessary to make short trips or not, based on the acquired data. All the gathered data allowed the creation of a database that will become the baseline to improve future drilling projects in those fields.
The tool uses a quartz crystal type transducer that grants high resolution and accurate readings in real time and memory of annular pressures and bore pressures. Additionally, ECD (Equivalent Circulating Density) and ESD (Equivalent Static Density) measurements are calculated and this last one also defines an inherent value of the EMW (Equivalent Mud Weight). The tracing of these values show the performance of the drilling fluid and an ECD working frame could be defined to ensure effective cleaning of the well.
In order to understand ECD, external factors affecting its behavior need to be denoted such as flow patterns, ROP or drilling fluid properties. Additionally, the applications of pressure records when performing FIT, CIT or LOT are explained.
Different scenarios of how the data was analyzed, interpreted and the decisions taken during the operations are shown in this paper.
