Research On Drilling And Completion Technology With Laying Radiant Tube Using Dual-tube Guided Drilling

When constructing a radiant tube,construction workers are required to perform high-strength physical work in a narrow sPace for a long time,which will lead to problems such as low construction efficiency,poor quality,and high-frequency safety accidents.The construction of the radiant tube has always been the bottleneck restricting the promotion and application of the radial collector well.Based on the current horizontal directional drilling technology,this Paper optimizes the bottom hole assembly and the water filter tube,designs a new guide short section.The new drilling technology provides a new option for the construction of the radiant tube efficiency and safety.Based on the literature review,determine to use HDD technology with two-layer drill pipe to lay the radiant tube.Two kinds of drilling solutions are proposed,namely: "One Drilling One Tube" and "One Drilling Two Tubes",and their advantages,disadvantages and applicable conditions are analyzed.The bottom hole assembly are designed,which is composited of Φ165mm tri-cone bit + Φ150mm guide short section + Φ144mm rope core drill pipe + Φ83mm HDD drill pipe.After comParing the six circulation modes,the “Drill Pipe Annulus-Center Hole” mode is preferred,which is most beneficial to keep the stability of the well wall.Subsequently,the principle design of the guide short section is carried out.Preferably,the detailed design of the eccentric straight is carried out,which is consists of the outer casing,the inner shaft,the conversion joint and the reducing joint.Based on the computer three-dimensional design software Soildworks,the three-dimensional model of each Part was established.After finalizing the revision,the drawings were sent to the factory for processing.Four kinds of well completion programs that are comPatible with the drilling program are proposed,and the advantages and disadvantages of each program are analyzed.Finally,it is concluded that,when the conditions permitting,the first choice is "One Drilling Two Tubes".For the water-rich unstable strata,a pull load prediction model is developed,which takes into account the gravity and buoyancy,the collapse pressure,the viscous of the mud,and the winch effect.Based on the MATLAB numerical calculation software,the results of the new model and other models are comPared,it is found that the new model predicts the pull load more in line with the actual situation.Using the new model,the water filter tube is optimized.The field test is carried out in the low permeability powder sand stratum,the shaft is formed by the rotary drilling rig,and the radiant tube is constructed by the HDD technology.After three times drilling,six radiant tubes are laid in the ground,which fully demonstrated that the new method has the advantages of high efficiency and safety.