Abstract:In order to solve the problem of difficulty in cleaning the annular cuttings in the reaming construction of large-diameter horizontal directional drilling, a horizontal directional drilling jet reverse circulation reamer was designed based on the principle of jet pump, and its chip removal performance was studied through indoor experiments. In the indoor experiment, three kinds of quartz sand particles (0.5-1 mm, 1-2 mm and 2-4 mm) were selected, and two muds with different Markov funnel viscosities were configured. The rock debris particles were studied by the controlled variable method. The influence of factors such as diameter, mud type, reamer speed and cuttings concentration on the efficiency of reverse circulation reamer. The test results show that the reamer designed solely considering the reverse circulation to form the suction effect has lower actual chip removal efficiency. The stirring effect of the convex cone structure and the close contact between the reamer and the hole wall can improve the cuttings. The removal efficiency has a positive effect; under certain conditions, the smaller the particle size of the cuttings, the greater the viscosity of the mud, and the greater the concentration of the cuttings, the higher the cuttings discharge efficiency of the jet reverse circulation reamer; when other conditions are constant, The cuttings removal efficiency reaches the maximum when the reamer speed is about 40 rpm; the maximum chip removal efficiency of the reamer is as high as 73.15% within the range allowed by the test conditions, which has strong practical value.