Dual-channel drill bit with drilling fluid switching function

Abstract

The invention discloses a dual-channel drill bit with drilling fluid switching function, which comprises a connected drill body and a dual-channel joint. The dual-channel joint includes a joint outer pipe, a joint inner pipe, a slide valve assembly located in the inner cavity of the joint inner pipe, and an inner joint There is an annular passage between the pipe and the outer pipe of the joint, and the inner pipe of the joint is provided with an inner pipe flow hole that communicates with the annular passage; the slide valve assembly includes a core pipe and a slide valve that is slidingly sealed between the joint inner pipe and the core pipe. The slide valve divides the inner tube cavity of the joint into the upper cavity of the inner tube and the lower cavity of the inner tube. The top of the core tube is closed and the bottom is open. The upper tube wall of the core tube is equipped with the upper part of the core tube. Flow holes; when drilling with the dual-channel drill bit of the present invention, under the action of the high and low temperature drilling hydraulic pressure difference, between the flow holes at the upper part of the core pipe and the upper chamber of the inner pipe, and between the flow holes at the lower part of the core pipe and the lower chamber of the inner pipe Periodically turn on or off, automatically switch between high and low temperature drilling fluids alternately, realizing variable temperature drilling and efficient rock breaking.

Description

technical field [0001] The invention relates to the technical field of oil and gas exploration tools, in particular to a dual-channel drill bit with a drilling fluid switching function. Background technique [0002] The drillability of rock is the ability of rock to resist the damage of drill bits, which is determined by the physical and mechanical properties of the rock itself and the rock-breaking ability of the drill bit. At present, the methods of increasing the drilling speed for high-drillability formations mostly focus on improving the rock-breaking ability of drilling tools, passively adapting to the rock drillability of the drilled formation, and the speed-up effect is not good. As a heterogeneous, discontinuous and anisotropic geological material, rock temperature has a significant impact on its physical and mechanical properties and deformation characteristics. Using the temperature effect to change the original physical and mechanical properties of the rock can ...

AI Technical Summary

Problems solved by technology

At present, the drilling speed increase methods for high drillability formations are mostly focused on improving the rock breaking ability of drilling tools, passively adapting to the rock drillability of the drilled formation, and the speed increase effect is not good

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