Controllable track lateral drilling tool and method

Abstract

The invention discloses a controllable track lateral drilling tool and method. The controllable track lateral drilling tool comprises a high-passing-ability lateral drilling section and a drilling power transmission section, wherein the high-passing-ability lateral drilling section can achieve drilling of an extending well section of a short-extremely-short-radius well section through the short-extremely-short-radius well section extending from the lateral direction of a main borehole. According to the designed controllable track lateral drilling tool, the borehole can be obliquely drilled at the tail end or any position in the middle of an original borehole track in a short-extremely-radius mode and then extends and is drilled in the lateral direction; and meanwhile, the controllable track lateral drilling tool has engineering feasibility and practical value on thin reservoir development, remaining oil potential tapping, under-salt reservoir horizontal well development, multi-layer system merging development, coal bed gas development, coal mine underground gasification development, unconventional oil and gas development, shallow horizontal well drilling, seabed shallow horizontal well drilling and development of other kinds of minerals.

Description

technical field [0001] The invention relates to the fields of drilling technology and oil and gas exploitation, in particular to a controllable trajectory lateral drilling tool and method. Background technique [0002] The control of production costs has always been the goal pursued by oil and gas drilling. With the development of unconventional oil and gas fields, the requirements for drilling equipment are getting higher and higher. Automatic, intelligent and efficient drilling technology has become the mainstream of reducing costs and improving efficiency. ; In addition, drilling technology also has a large number of applications in the field of geological engineering and mineral development. [0003] The application background of this technology is to sidetrack branch wells at any position in the existing main wellbore with a short-very short radius, and then continue to extend the branch wellbore in a direction different from the axis of the main wellbore or in the exis...

AI Technical Summary

Problems solved by technology

[0004]At present, coiled tubing is used to transmit bent joint screw motors to realize sidetracking drilling with controllable trajectory of medium and short radius, but the orientation method is slide steering, and the whole drill string does not rotate. The drilling circulating medium drives the screw to drive the drill bit to rotate, and changes the inclination and azimuth performance of the drilling tool through the change of the tool face angle of the bent joint. There are limitations such as the drilling tool does not rotate during directional operations and cannot complete short-radius directional drilling operations. , the accuracy of the wellbore trajectory is poor; and because the coiled tubing has inherent disadvantages such as non-rotatable and low strength, the pipe string is easy to be damaged and broken, and is not suitable for bearing high torque. Therefore, it is almost incapable of performing short-radius lateral drilling, and it is even more incapable of working in the range of ultra-short radius and extremely short-radius lateral drilling.

[0005]Another method to achieve short-very short radius lateral drilling is to drive the drill bit through a flexible drill pipe to achieve short-very short radius lateral drilling, namely Short drill pipes with a single section length less than 1.5 meters are connected in series to form a flexible drill string. The short drill pipes rely on the ball head and the ball bowl to transmit the tension, and rely on the spline set between the ball head and the ball bowl to transmit the torque. Through the flexible drill string The drill string drives the drill bit at the bottom to rotate to break rock; this method can rely on the deflection of the skewer to achieve short-to-very short radius sidetracking, but the wellbore trajectory control and certain accuracy cannot be achieved during the further wellbore extension process. The wellbore trajectory is severely buckled, which hinders the drilling of the drill bit, and the twisted and uncontrollable empirical trajectory is difficult to meet the site requirements

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