Abstract
Regions of difficult drilling including Alaska's North Slope with easily destabilized shales and formations in the Alberta's Deep Basin with inherently narrow drilling windows offer numerous drilling challenges. Managed Pressure Drilling (MPD) techniques are implemented for a multitude of reasons including reducing pressure cycling, ensuring wellbore stability limits are adhered to, managing swab and surge while tripping, and managing rollover style fluid to fluid displacements.
Effective MPD techniques require accurate surge, swab, and annular friction models as they are critical to drilling operations. A comparison of modelled data to Pressure While Drilling (PWD) measurements indicate that established fluid models alone cannot be relied on for accurate modelling. A series of data comparisons show the limitations of established models to accurately predict wellbore hydraulics. The implications of model limitations on MPD operations specifically are shown and their differences to actual data are quantified.
