Controllable Variable Diameter Stabilizer Driven by Saw Gear

Abstract

The invention relates to a controllable variable-diameter stabilizer driven by a sawtooth wheel. The controllable variable-diameter stabilizer comprises a body, wherein an upper core shaft and a lower core shaft are arranged in the body, the upper core shaft and the lower core shaft are in sealing connection, and drilling fluid channels are formed in an inner cavity of the upper core shaft and an inner cavity of the lower core shaft; a signal column is arranged at the lower end of the lower core shaft; a restoration spring is arranged on the upper core shaft, a spring seat is arranged at the lower end of the restoration spring, and the spring seat is clamped to the variable-diameter position in the upper end of the body; an inclined block is arranged at the variable-diameter position of the body and outside the upper core shaft, a centralizing piston corresponding to the outside of the inclined block is connected in a piston hole of the body, and the lower portion of the centralizing piston is connected with the inclined block through a T-shaped groove; an oil cavity is formed between the upper core shaft, the lower core shaft and the body; an annular hole is formed in the lower end of the body, a balance piston is arranged on the upper side and at the position corresponding to the lower core shaft, a differential-pressure piston and a support barrel are arranged on the lower side and at the position corresponding to the lower core shaft, and a sawtooth wheel driving mechanism is arranged outside the lower core shaft. According to the stabilizer, the work states of the variable-diameter stabilizer can be changed by switching on and off the well pump, and repeated transposition is achieved.

Description

technical field [0001] The invention relates to a controllable variable-diameter stabilizer used in drilling operations of directional wells, horizontal wells and extended displacement wells in the petroleum industry, and belongs to the field of downhole tools in drilling engineering. Background technique [0002] In the process of drilling directional wells, horizontal wells and extended-reach wells, in order to ensure that the actual drilling trajectory meets the requirements of the designed wellbore trajectory, one of the methods is to use the controllable variable diameter stabilizer controlled by the switch drilling pump, but now There are following problems in this type of variable-diameter stabilizer developed: [0003] (1) The curves and surfaces on the cam that internally controls the variable diameter of the stabilizer are complex and difficult to process; [0004] (2) The cam pin is easy to wear, which leads to the failure of variable diameter control; [0005] ...

AI Technical Summary

Problems solved by technology

[0003] (1) The curves and surfaces on the cam that internally controls the variable diameter of the stabilizer are complex and difficult to process;

[0004] (2) The cam pin is easy to wear, which leads to the failure of variable diameter control;

[0005] (3) A large pressure difference between the inside and outside of the drilling tool is required to work, which limits the selection of the water hole of the drill bit and also causes excessive pressure loss of the water head

[0006] Chinese patent 201310691430.8 discloses a "mechanical-hydraulic variable-diameter stabilizer". The cam mechanism used in this stabilizer has a complex cam structure and is difficult to process. The cam pin is in a state of sliding friction on the structure, which is easy to wear and difficult to popularize and apply.

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