Abstract
Equivalent circulating density for the used drilling fluids while drilling operations should meet the requirements such as stability of hole section, generated drilling cuttings carrying, mud lubrication & damage of hole section control. The hydrostatic column of mud have to be higher than the pressure of drilled formation, however, must be manipulated to be less than the estimated fracture value of wall of drilled hole section. Thin window while drilling can lead to hole problems such as well control incident (influx, kick and blowout) if the used ECD profile cannot be kept below the margin of fracture gradient and above sand face gradient drilling window margin. Also, could cause damage for drilling formation of hole section and loss of circulation during drilling operations. Obtaining down-hole values for mud properties like density and rheology, contributes to have precise prediction of real time ECD. Evaluation of real time observation of ECD and drop in pressure will allow operators to have more control over annular pressure throughout the wellbore. Which will reduce the risk of kicks, and loss circulation. In this paper, a new models of automated or effective density of drilling mud (EMW) and equivalent density of circulating mud (ECD) while drilling were developed to empower drilling team to closely monitor, optimize and allow immediate interventions. Drilling parameters and fluid rheology of same drilling fluid, hole section were collected for this development. The resulted EMW and ECD were benchmarked against commercial packages with advanced sensors and with strong agreement with absolute average error of (AAE) less than 2%. The developed drilling fluids models of EMW and ECD were applied, automated for time operating center (RTOC). The real time application will allow drilling team to optimize monitoring for performance and mitigate any potential risks for many drilling rigs without the need of using advanced commercial sensors.
