Central rotary jetting pulse internal-grinding drilling bit

Abstract

The present invention discloses a central rotary jetting pulse internal-grinding drilling bit. Different from a conventional PDC drilling bit, the central rotary jetting pulse internal-grinding drilling bit is added with a pulse generating device, a central rotary jetting rock breaking device, a negative pressure swabbing device, and a rock cuttings internal-grinding device. The pulse generating device comprises a drilling fluid flow channel, a feeding cavity, a resonant cavity, a resonant tube outlet, and a diverging area, and based on an organ pipe, generates pulse jets by exciting fluid resonance. The central rotary jetting rock breaking device comprises a down-jet bypass flow channel, a down-jet central self-rotating flow channel, a central self-rotating nozzle, and a blade; and based on mutual coordination between the down-jet bypass flow channel and the self-rotating nozzle, the rock breaking and rock clearing efficiency is improved. The negative pressure swabbing device comprises a reverse high-speed flow channel, and a swabbing cavity; negative pressure is formed in the swabbing cavity based on the high-speed characteristic of reverse jets to swab rock cuttings, and the cuttings hold-down effect is reduced. The rock cuttings internal-grinding device comprises a mixing cavity, a throat, an accelerating cavity, an internal-grinding cavity, an internal-grinding body, a bypass, and a dispersing cavity, and is used for breaking rock cuttings based on a high pressure acting force and a water-wedge effect; the cuttings carrying efficiency is improved; and a cuttings bed is cleaned.

Description

technical field [0001] The invention belongs to the field of oil and gas well drilling, and specifically designs a center rotary spray pulse internal grinding drill bit. Background technique [0002] In horizontal well drilling, cuttings are often accumulated due to unfavorable rock carrying and untimely cleaning, especially large-grained cuttings. Once the cuttings leave the bottom of the well without effective cutting, they cannot return to the bottom of the well for crushing. The resulting cuttings bed seriously restricts the ROP and drilling cost, leading to the occurrence of complex drilling accidents such as pump holding, poor drilling, and even stuck drilling. Conventional solutions are mostly to increase drilling speed, increase displacement, add lubricant, lift and lower the drilling tool in a short distance, and push the large-grain cuttings near the drill bit back to the bottom of the well for repeated crushing. Although there is a certain effect, but The ROP is ...

AI Technical Summary

Problems solved by technology

[0002] In horizontal well drilling, cuttings are often accumulated due to unfavorable rock carrying and untimely cleaning, especially large-grained cuttings. Once the cuttings leave the bottom of the well without effective cutting, they cannot return to the bottom of the well for crushing

The resulting cuttings bed seriously restricts the ROP and drilling cost, leading to the occurrence of complex drilling accidents such as pump holding, poor drilling, and even drilling

Conventional solutions are mostly to increase drilling speed, increase displacement, add lubricant, lift and lower the drilling tool in a short distance, and push the large-grain cuttings near the drill bit back to the bottom of the well for repeated crushing. Although there is a certain effect, but The ROP is reduced, and the cuttings bed in the mid-drilling stage cannot be solved in a timely and effective manner

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