Optimization of Drilling Performance Based on an Intelligent Drilling Advisory System

Abstract

Optimization of drilling parameters during drilling operations is a key component to obtain maximum rate of penetration (ROP) as well as minimizing the drilling cost. Advancement in computer technologies and communication are among the most important factors that can contribute to drilling optimization. In the current work, a novel rig advisory system is developed to continually improve ROP and the drilling performance. Conventionally, drillers apply drilling parameters (weight-on-bit, rotary speed and pump rate) according to past experience or to parameters specified in the drilling program. These parameters are usually kept constant over a long interval regardless of the formations being drilled. However, it is well-known that keeping constant drilling parameters to drive the bit will lead to redundant depth of cut (DOC), inducing stick-slip vibration that leads to low ROP, higher drilling specific energy (DSE), and potential damage to the bottom-hole assembly (BHA). An intelligent drilling advisory system (IDAS), based on a soft-closed-loop solution with multiple regression analysis called optimum parameters global retrieval, has been established. Integrated with machine-learning methodology (Principal component analysis), the response of the drilling parameters with lithology changes was analyzed in real time. Additionally, the optimum control parameters direction were obtained from the gradient search and decision tree algorithms. This system monitored the relationship between the ROP and input energy delivered to the bit in real time, and calculated the optimized drilling parameters. The work presented how the IDAS procedures were applied in China, how the data was interpreted, and how optimum working parameters were obtained to guide drillers to improve drilling performance and reduce non-productive time (NPT). IDAS has been introduced to hard formation drilling, which proved to be a success in real-time advisory aiding drillers applying proper working parameters for maximum ROP. Field applications of IDAS guidance showed significant ROP improvement compared to that of conventional drilling. As an effective tool for further achieving the optimum DOC, a novel control system achieved satisfactory outcomes that overcome the drilling challenges in Saudi Arabia and China, which will serve as a step forward towards automated drilling operations.