Evaluating the Effect of Stabilized Weight Transfer to the Bit on Mechanical Specific Energy in Horizontal Well Drilling

This study investigates the effect of stabilizing axial load transfer to the bit on mechanical-specific energy during horizontal well drilling. To analyze drilling regimes, field data on WOB, ROP, RPM, TOB, and MSE were used and processed using z-score standardization, outlier removal based on the IQR criterion, and k-means clustering. The selected number of clusters was determined using the elbow method and silhouette analysis; after filtering, the dataset included 1750 observations, and the six-cluster solution was selected for exploratory interpretation. It was found that the lowest MSE values were characteristic of clusters 0, 1, and 5, among which cluster 5 demonstrated the most favorable combination of WOB, ROP, and energy efficiency. Clustering the modeled data confirmed the possibility of identifying drilling regimes with reduced MSE under a stabilized-load scenario. The predicted MSE reduction should be interpreted as a scenario-based, idealized model-based estimate obtained under quasi-steady assumptions rather than as a field-validated performance gain. The results may be used to support the selection of rational drilling parameters and to guide the further development of drilling control systems for horizontal well drilling.