The primary goal of screen design for steam assisted gravity drainage (SAGD) operations is to prevent the entrance of the poorly or unconsolidated sand into the production flow stream, which could cause serious damages to the downhole/surface facilities. Current screen design approach fits one screen opening size for the entire length of the well, which leads to a conservative screen opening to avoid sand production along the well. This study introduces a new approach to design the screen opening, considering different opening sizes along the horizontal well.
The proposed workflow in designing the optimum screen opening relies on well logs and core analysis to map the grain size distribution within reservoir through a geostatistical approach. Considering the horizontal well path and the changes in liner length due to installation and thermal loads, we design the screen aperture size to optimize the screen selection based on sand facies present in different sections of the wellbore. This enables us to provide different screen opening for different sand facies along the horizontal well.
The new approach provides a more detailed design for screen opening for the horizontal well according to the sand size distribution within the reservoir instead of trying to fit one opening size for the entire horizontal section. It also considers the thermal expansion of the joints. This approach designs the screen opening for different sand facies along the horizontal well in a way which obtains the highest productivity and lowest produced sand.
This paper provides a novel workflow for the design and optimization of screen for horizontal wells, which could be used to optimize the design of different standalone screens such as slotted liner, precise punch screen (PPS) and wire wrapped screen (WWS).