Simulation and Experimental Study on Fishing Performance of Vacuum Suction Wellbore Cleaning Tool

During the completion of shale gas wells, bridge plug debris and debris particles are often left at the bottom of the well, which are difficult to clean up, pose a serious risk to wellbore operations, and reduce productivity. In order to solve the difficulty of cleaning the debris at the bottom of the well, a kind of wellbore cleaning tool is proposed based on the principle of negative jet pressure and liquid-solid two-phase flow theory. The finite element analysis method and laboratory test were used to verify the function of cleaning tools: the finite element method can effectively reflect the principle and process of dredging bottom debris with cleaning tools. In order to improve the applicability and fishing ability of wellbore cleaning tools, factors influencing the performance of cleaning tools were analyzed as follows: choosing high-density and low-viscosity working fluid is beneficial to improve the negative pressure effect of cleaning tools. Under the conditions of wellbore safety and economy, increasing pump pressure and displacement and reducing annular pressure can effectively increase the fishing performance of cleaning tools.