Rethinking Long-Standing ROP Dogma: Solids- It's All That Matters

Abstract This paper challenges traditional long-standing ROP dogma by presenting a comprehensive analysis of field data from the Western Canadian Sedimentary Basin (WCSB), which highlights solids content (low and high gravity solids) as a dominant impact on the rate of penetration (ROP). The study compares the ROP performance of traditional brine systems (TBS), a novel viscosified recycled brine system (VRBS), and invert emulsions across seven case studies. The analysis integrated field data with established petroleum engineering principles to show that the VRBS, when containing minimal solids, despite having higher plastic viscosity (PV) and forming a filter cake, achieved ROPs comparable to traditional brines. This finding contradicts long-standing theories that suggest higher plastic viscosity and a filter cake are detrimental to drilling performance. The research provides compelling evidence that the accumulation of solids, even at concentrations as low as 1%, leads to a significant decrease in ROP. This is evident by the VRBS's declining ROP as solid content increased. In contrast, the traditional brine systems sustained performance by maintaining a low solids profile through flocculation. The study concludes that effective solids management is a critical factor for maximizing ROP and overall drilling efficiency, thereby challenging traditional theories prioritizing plastic viscosity, filter cake, and the chip hold-down effect. Additionally, micro data from fluid displacement and macro data from multi-well pads consistently show a strong correlation between ROP and solids content. These results also indicate that high solids loading contributes to increased bit wear and reduced longevity, while lower solids content leads to enhanced bit performance and more meters drilled per bit run.