Drill bit for broken stratum drilling

Abstract

The invention provides a drill bit for broken stratum drilling. The drill bit is composed of a drill bit outer cylinder, a spring, a vertical rod and a drill bit cutter disc. According to the working principle of the drill bit, a drill rod and the drill bit descend to the bottom of a drill, pressure is applied to the drill bit by the drill rod and transmitted to the vertical rod through the spring, pressure is applied to the upper portion of the drill bit cutter disc, the drill bit cutter disc rotates around a connecting ring, and the lower portion of the drill bit cutter disc stretches out of a sleeve; meanwhile, a groove in the drill bit outer cylinder is meshed with a convex cone of the drill bit cutter disc and a concave-convex joint of the drill rod sleeve; rotating torque of the drill rod is transmitted to the drill bit outer cylinder, the drill bit outer cylinder transmits the rotating torque to the drill bit cutter disc for rock breaking, a drill hole sleeve extends downwards, and rock debris is conveyed to the ground through a slurry circulating belt; after drilling is finished, the drill rod is lifted, the drill bit spring is retracted, the vertical rod is pulled, the drill bit cutter disc is rotated to be retracted into the sleeve, and hole collapse of a drilled hole is prevented through the drill hole sleeve; the purpose that the drill bit is applicable to jointed rock mass, a stratum where hole collapse is likely to appear during conventional drilling, and drilling construction of a coal mine goaf covered with a broken stratum is achieved.

Description

technical field [0001] A drill bit is invented which is suitable for the drilling construction of fractured rock mass, formations prone to hole collapse in conventional drilling, and damaged rock formations in goafs of coal mines. Background technique [0002] From the perspective of drilling engineering, Academician Luo Pingya’s definition of fractured formations: formations that were originally broken due to tectonic stress (completely broken, a large number of fractures...) and fractured formations under the overlying pressure after the wellbore is formed. The salient features of this type of formation are: incomplete fragmentation, poor cementation, developed fractures, and often accompanied by formation pressure; these characteristics determine the poor stability of the hole wall in the broken formation, and often occur in complex holes such as hole wall collapse, block falling, and drill sticking. ACCIDENT. [0003] At present, the way to stabilize the pore wall of th...

AI Technical Summary

Problems solved by technology

Drilling in this type of formation is more likely to cause hole collapse and drill sticking, which affects the smooth progress of drilling and even makes drilling operations impossible

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