Novel PDC drill bit with combination teeth

Abstract

The invention discloses a novel PDC drill bit with combination teeth. The drill bit comprises a drill bit body, a plurality of scrapers are distributed on the drill bit body, the structure outlines of cutting teeth of the scrapers comprise inner cones, nose parts, outer cones, circular beads and gauge protection blocks, and various cutting teeth are arranged on the multiple scrapers; with the rotation direction in the cutting process of the scrapers as the front, front-row teeth on at least one of the scrapers on the drill bit body comprise two kinds of shearing teeth, and rear-row teeth on the scraper at least comprise one kind of the shearing teeth or one kind of limiting teeth; and the shearing teeth comprise disc-shaped shearing teeth and rib-shaped shearing teeth, and the limiting teeth comprise spherical cylindrical teeth and conical cylindrical teeth. According to the drill bit, by designing a structure of the cutting teeth of the drill bit with the combination of the various cutting teeth and cutting depth control over the drill bit, the torque fluctuation of the drill bit can be reduced, the ability of the drill bit to resist grinding and shocking can be improved, the service life of the cutting teeth of the drill bit can be prolonged, the cutting ability and the adaptability of the drill bit can be improved, the mechanical drilling speed of the drill bit can be increased, the stability of the drill bit can be improved, and the well drilling cost can be lowered for users.

Description

technical field [0001] The invention relates to a diamond drill bit, in particular to a novel mixed-tooth PDC drill bit used in hard formation drilling of oil and natural gas drilling. Background technique [0002] In the exploration and development of oil and natural gas resources in recent years, deep well drilling and ultra-deep wells have become the main force to improve the development of oil and gas resources. In such oil and gas drilling, hard formations and abrasive formations are often encountered. It has become an important way and method to shorten the drilling period and reduce the drilling cost. It is known that in the drilling of hard formations and abrasive formations, in order to improve the stability of the drill bit and prolong the service life of the drill bit, the method of increasing the drilling pressure is usually used to increase the drilling speed. The types of drill bits available to people are divided into roller cone bits and fixed cutter bits. I...

AI Technical Summary

Problems solved by technology

However, in the process of drilling with PDC bits, people do not want to use high WOB, because increasing the WOB will increase the length of the drill collar, which will increase the pressure loss of the drill string, increase the pressure and power consumption of the pump, and increase the righting reduce wear and tear on drill strings, reducing drilling efficiency and drilling costs

At the same time, in drilling, increasing the drilling pressure will accelerate the wear of the drill bit and the speed of the blunt drill bit, which will increase the number of drill bits used; under the condition that the drill bit is worn out, the service time of the drill bit should be extended, in order to achieve an acceptable drilling rate. Under normal circumstances, only increase the WOB, because the relationship between the wear of the drill bit and the WOB is not a linear relationship, but an exponential relationship; in a specific formation, increasing the WOB of a small value under the existing WOB will sharply accelerate the drill bit. Wear of cutting teeth, as tooth damage is accelerated by thermal wear and impact damage of the teeth

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