Least squares modeling of the depth of cut of reservoir rock from real-time drilling parameters

Abstract

Exploration is the process of a wellbore being drilled below the Earth’s surface, and produced through a production tubing to the wellhead. In drilling modeling, optimization and statistical analysis are important. Optimizing drilling process is a technical strategy to drill wells more productively. This paper aims at least squares modeling and statistical analysis of the depth of cut of reservoir rock from real-time drilling parameters. Real-time drilling data was obtained from drilling process of the reservoir rock in North Brae Sea (offshore) with the coordinate “58.70 N 1.30 E”. Within the data set, “Revolution Per Minute (RPM)” (rev/min), “Rate of penetration (ROP)” (ft/min), are the independent variables, and the “depth of cut”, the response variable. Maximum depth of cut is found to be 1.0533 and achieved at Revolution Per Minute (RPM) and Rate of penetration (ROP) values of 81.4626 and 85.8096, respectively. Least squares method was assessed for fitting the data set and found to provide a decent fit to the drilling data. Statistical analysis reveals that the model is highly significant with R squared value, adjusted R squared value and Predicted R squared values value of 100.00%, 100.00% and 99.99%, respectively. Hence, the linear model developed could be used for predicting the depth of cut of the reservoir rock.