Variable-diameter stabilizer and variable-diameter stabilizer system

Abstract

The invention provides a variable-diameter stabilizer. The variable-diameter stabilizer comprises a housing, an upper mandrel and a lower mandrel, wherein an upper high-pressure mud cavity is formed in the upper mandrel in the direction of the axial line of a housing, a lower high-pressure mud cavity is formed in the lower mandrel in the direction of the axial line of the housing, the variable-diameter stabilizer further comprises a mud pressure changing device, the mud pressure changing device comprises a mushroom head assembly and a center hole, the center hole is formed in the upper end of the upper mandrel, the diameter of the upper end of the center hole is larger than that of the lower end, and the center hole is communicated with the upper high-pressure mud cavity; the mushroom head assembly is arranged above the center hole and fixed on the inner wall of the housing; and when the variable-diameter stabilizer is positioned in a working state, the area of passage of mud at the mushroom head assembly and the center hole is maximum, the pressure born by the variable-diameter stabilizer in the working state can be effectively reduced, and the variable-diameter stabilizer is safe and reliable. The invention further provides a variable-diameter stabilizer system, which can effectively reduce the pressure born by the variable-diameter stabilizer in the working state, and the variable-diameter stabilizer is safe and reliable.

Description

technical field [0001] The invention relates to the technical field of petroleum and geological drilling equipment, in particular to a variable-diameter stabilizer and a system thereof. Background technique [0002] As everyone knows, when oil extraction or geological prospecting, often need to carry out drilling well underground with drill bit. Because in some oil exploration or geological exploration, its drilling depth can reach several thousand meters. In the drilling process, in order to ensure the quality of drilling and the safety of the drill bit and drill pipe, it is often necessary to control the inclination angle of the drilled hole within a certain range, that is, to ensure that the drill bit is drilled according to the preset trajectory . [0003] At present, in order to ensure the inclination angle of the wellbore, people often install a variable diameter stabilizer on the top of the drill bit, and use the variable diameter stabilizer to fit the inner wall of...

AI Technical Summary

Problems solved by technology

[0006] However, when the above-mentioned mud pressure changing device is used, when the variable diameter stabilizer is in the drilling working state, the distance between the central hole in the orifice plate assembly and the mushroom head assembly is the smallest, and the mud pressure is relatively highest; therefore, the variable diameter will be stable. The variable diameter stabilizer is in a high-pressure state, and because the variable diameter stabilizer needs to be in the drilling working state for a long time, it is easy to cause damage or even damage to the variable diameter stabilizer, so that ground operators cannot monitor and record the mud pump through the mud pump pressure gauge. If the mud pressure is low, the working status of the variable diameter stabilizer cannot be accurately known, which will affect the drilling work

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