PDC (Polycrystalline Diamond Compact) drill bit suitable for shale gas well shale stratum drilling

Abstract

The invention relates to drilling equipment of shale gas, in particular to a PDC (Polycrystalline Diamond Compact) drill bit suitable for shale gas well shale stratum drilling. The drill bit comprises a crown portion with a plurality of tool wings, wherein the revolution contour line of the crown portion consists of three sections, namely an inner cone section extending outwards along an inner cone from the concave center of the crown portion of the drill bit, a circular arc section extending from the edge of the inner cone to a gauge section on the outer side and a gauge section with a straight line contour, the circular arc section is formed by combining a plurality of sections of circular arcs with different radii, and the radii of the circular arcs are gradually increased from inside to outside; cutting teeth are distributed on the three sections of counters. The PDC drill bit can be suitable for drilling operation of shale stratums, and is high in drilling efficiency and long in service life.

Description

technical field [0001] The invention relates to drilling equipment for shale gas, in particular to a PDC drill bit suitable for drilling shale formations of shale gas wells. Background technique [0002] Shale gas resources, as an effective replacement resource for conventional oil and gas resources, have attracted much attention in recent years. However, in the actual drilling of shale gas wells, especially in the process of drilling shale formations, due to the lack of targeted PDC drill bits, the drilling efficiency is low and seriously affects Efficient exploration and development of shale gas. Because shale formations generally have the characteristics of ancient formations, high compressive strength, high siliceous and carbon content in shale, and even large siliceous strips. Conventional PDC bits cannot simply break rocks by shearing, but work by various rock breaking methods such as rolling, grinding and shearing, especially when drilling siliceous strips, causing t...

AI Technical Summary

Problems solved by technology

Conventional PDC drill bits cannot simply break rocks by shearing, but work by various rock breaking methods such as rolling, grinding and shearing, especially when drilling into siliceous strips, causing the cone top and shoulder The cutting teeth are prone to chipping and early wear, and lose the rock-breaking effect, thus affecting the service life of the drill bit and failing to achieve the ideal ROP and footage

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