Special-structured PDC drill bit

Abstract

The invention belongs to the technical field of geological exploration drill tools, and relates to a special-structured PDC drill bit. Cutting wings and stabilizing wings are alternately uniformly arranged at intervals in the circumferential direction. Portions, exposing a drill bit body of the stabilizing wings are shorter than the cutting wings. PDC cutting teeth and spherical stabilizing teethare arranged at crown portions of the cutting wings. Drill bit protection necks are arranged on the lateral faces of the cutting wings and the stabilizing wings. PDC side direction cutting teeth and spherical abrasion resisting teeth are inlaid at the drill bit protection necks. The drill bit body is provided with fluid channels. Connecting screw thread is arranged at the top of the drill bit. Thecutting wings and the stabilizing wings are provided with the PDC cutting teeth. The PDC side direction cutting teeth are arranged at root portions of the cutting wings and the stabilizing wings meanwhile. The spherical stabilizing teeth are arranged at the drill bit protection necks. The structure is simple, and application is safe and convenient. The number of the cutting wings can be reduced,teeth arrangement density is lowered, pressure intensity of single tooth is improved, the special-structured PDC drill bit can be effectively fed into stratigraphic broken rocks, and can stably work at the shaft bottom. Rock breaking efficiency of the drill bit is high, the service life is long, and shaft body quality is guaranteed.

Description

Technical field: [0001] The invention belongs to the technical field of geological exploration drilling tools, and relates to a drill bit for drilling underground minerals such as oil and natural gas, in particular to a special-shaped structure PDC drill bit suitable for drilling oil, natural gas or other minerals. Background technique: [0002] Formation drilling is essentially a direct dialogue between the drill bit and the formation, and the performance of the drill bit directly affects the drilling speed and economic benefits. At present, the main types of drill bits involved in the drilling process include scraper bits, roller cone bits, PDC bits and diamond bits, among which roller cone bits and PDC bits are more commonly used, especially in the drilling construction of oil and natural gas fields. Compared with wheel bits, PDC bits have the advantages of simple structure and long life, and are suitable for drilling long well sections. Therefore, PDC bits are more commo...

AI Technical Summary

Problems solved by technology

The cutter wings of the existing full-scale drilling PDC bit are all cutting wings. Therefore, when the drilling pressure is applied, the pressure is evenly distributed on each cutting tooth of the PDC bit. The more cutting wings of the PDC bit, the greater the cutting tooth density. Under the same drilling pressure, the pressure distributed on the single cutting teeth is smaller, resulting in the shallower penetration depth of the PDC bit into the formation, especially when drilling into a strong plastic formation, it cannot effectively break the formation rock, resulting in serious "stick-slip" "effect, the ROP is extremely reduced; and blindly increasing the WOB or reducing the number of blades will easily lead to adverse conditions such as well deviation, bit whirl, and downhole drilling tool fatigue.

Images