Downhole friction reduction and resistance reduction tool and method based on mechanical decoupling

Abstract

The invention relates to an underground friction and resistance reducing tool and method based on mechanical decoupling, and belongs to the technical field of oil and gas resource drilling tools. The invention discloses an underground friction reduction and resistance reduction tool and method based on mechanical decoupling. The underground friction reduction and resistance reduction tool comprises an upper shell, a lower shell, a lower connector and a drilling fluid return pipe. An unloading connecting assembly I, a torque axial reversing assembly and an unloading connecting assembly II are sequentially arranged in the lower shell. A transfer positioning device I, a power input device, a torque increasing device I, a transfer positioning device II, a power separation device I, a torque increasing device II, a transfer positioning device III, a power separation device II, a torque increasing device III, a transmission shaft I and a transmission shaft II are sequentially arranged in the upper shell. The working torque of the downhole friction and resistance reducing tool is controlled by directly adjusting the drilling speed of a drill column through ground operators, so that sliding guide drilling under the condition that the drill column rotates is achieved, and the technical problems that the friction resistance of the drill column is high, backing pressure is serious, the mechanical drilling speed is low, and a horizontal section is difficult to extend are solved.

Description

technical field [0001] The invention relates to a well friction and drag reduction tool and method based on mechanical decoupling, and belongs to the technical field of oil and gas resource drilling tools. Background technique [0002] Compared with conventional vertical wells, the horizontal section of horizontal wells can contact the reservoir in a large area and greatly improve oil recovery. It is a key technology for the development of unconventional oil and gas such as shale oil and gas, tight oil and gas, and coalbed methane. However, horizontal well drilling technology generally faces a series of challenges such as high drill string friction, severe back pressure, low ROP, and limited horizontal extension capability. Horizontal well drilling mainly adopts two drilling methods: sliding steerable drilling and rotary drilling. When the slide-steering drilling method is adopted, the screw drilling tool drives the drill bit to rotate under the driving of the drilling flui...

AI Technical Summary

Problems solved by technology

The friction in the static friction area is still high, and the tool face must remain stable; for deep horizontal wells with long horizontal sections, due to the continuous increase in well depth and horizontal section length, the friction / torque of the drill string continues to increase, and the effect of torsional drag reduction is insufficient Problems such as good performance and weakened control ability of the tool face are becoming more and more prominent. Even by strengthening the torsional drilling parameters, it is difficult to effectively improve the drag reduction effect.

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