Drilling Optimization by Means of Decision Matrices and VB Tool Applied to Torsional Vibration and MSE Surveillance

Abstract

Nowadays, the exploration of different deep subsurface energy-related natural resources (oil/gas, natural hydrogen, geothermal, among others) is gaining importance. The exploration of these deep subsurface resources can present several challenges, such as complex lithology to be drilled, high depth to be reached, and considerable rock hardness, among others. In this context, the implementation of methodologies focused on real-time operational efficiency improvement has gained attention. Mechanical specific energy (MSE), rate of penetration (ROP), and even vibrations are key indicators that can be combined and used for drilling process optimization and efficiency improvement. These indicators are linked to operational drilling mechanic parameters, such as weight on bit (WOB), rotary speed (RPM), torque (TOR), and flow rate (FLOW). Despite this, multi-objective research considering both MSE and torsional vibration (stick–slip) has been largely overlooked in drilling optimization studies. Therefore, the main objective of this paper is to analyze field data from carbonate reservoirs using a multi-objective optimization approach based on torsional vibration, by means of stick–slip and MSE analyses. The focus is to minimize MSE values and mitigate stick–slip using self-developed decision matrices which consider WOB, RPM, and FLOW as key elements. The research results demonstrated that FLOW is a crucial parameter for minimizing torsional vibrations and should be prioritized in drilling operations, also for mitigating undesirable events. The optimization process yielded optimal WOB values for each RPM range (from 100 to 180 [rev/min]) and FLOW range (from 2200 to 3900 [L/min]). The decision matrix revealed that regions with high desirability correspond to high RPM (above 120 [rev/min]), with WOB varying from 5 to 13 [tf], and FLOW rates above 2300 [L/min]. Critical drilling conditions occur when low RPM, low FLOW, and high WOB (above 13 [tf]) are applied, as these conditions and this combination of parameters are most susceptible to release severe torsional vibrations, indicating a higher risk of operational problems.