Horizontal Well Cuttings Migration Mechanism under the Influence of Annulus Air Flow

Cuttings migration efficiency is a key issue in air drilling of horizontal wells, also a critical factor concerning the success of air drilling wells. Based on experimental analysis of cuttings particles migration pattern and particles initiation features, this paper suggests several migration patterns of cuttings. According to the research on the factors affecting the migration diversity of cuttings such as particle diameter, mechanic rotary rate of drill pipe, amount of air injected, this pater believes that cuttings leap further and migrate better during rotation of drill pipe, and further proposes that the bring-cuttings performance of horizontal well can be effectively managed by breaking cuttings and changing the amount of air injection, so as to improve the clearing efficiency of horizontal well pipes. The analysis results will provide reference for the improvement of cuttings migration efficiency in air drilling of horizontal wells.