Comprehensive review of cuttings transport in wellbore drilling: Mechanisms, challenges, and future directions

In the rapidly changing field of drilling technology, the efficient management of cuttings transport within the wellbore has become a critical challenge, especially as the complexity of deviated and extended-reach wells continues to grow. This review brings together experimental, numerical, and analytical studies on cuttings transport, underscoring the role of effective borehole cleaning in mitigating common drilling issues such as pipe sticking and poor cementation. It delves into the interactions among critical drilling parameters—such as annular flow rate, drillpipe eccentricity, fluid rheology, cuttings characteristics, and hole inclination—and their effects on the efficiency of cuttings transport. Descriptions of experimental facilities at various research institutes provide a global perspective on experimental studies of cuttings transport. A critical analysis of the existing literature highlights the primary role of the flow rate in cuttings transport and the significant effects of fluid viscosity, drillpipe rotation, and other drilling parameters on cuttings transport efficiency. This review underscores the complexity of the cuttings transport mechanism and the necessity of optimizing drilling conditions to ensure effective hole cleaning. The paper concludes by proposing future research directions to close existing gaps in knowledge and improve drilling efficiency, potentially reducing operational costs and lowering risks. This review offers a detailed reference for researchers and professionals in the drilling industry, aiding the development of cuttings transport strategies in complex wellbore environments.