Integrated cast matrix sleeve api connection bit body and method of using and manufacturing the same

Abstract

A drill bit including a bit body and an upper portion, wherein the bit body and the upper portion are comprised of a matrix material, and wherein the upper portion includes a threaded connection comprised of a machineable matrix material is disclosed.

Description

BACKGROUND OF INVENTION[0001]1. Field of the Invention[0002]Embodiments disclosed herein relate generally to matrix body drill bits and the methods for the manufacture of such drill bits.[0003]2. Background Art[0004]An earth-boring drill bit is typically mounted on the lower end of a drill string and is rotated by rotating the drill string at the surface or by actuation of downhole motors or turbines, or by both methods. When weight is applied to the drill string, the rotating drill bit engages the earth formation and proceeds to form a borehole along a predetermined path toward a target zone.[0005]Different types of bits work more efficiently against different formation hardnesses. For example, bits containing cutters that are designed to shear the formation frequently drill formations that range from soft to medium to hard. These cutters often have polycrystalline diamond compacts (PDCs) as their cutting faces, and are then called PDC bits.[0006]Roller cone bits are efficient and ...

AI Technical Summary

Benefits of technology

The patent text describes a drill bit made of a matrix material, with a threaded connection between the bit body and the upper portion. The technical effects of this design include improved durability, reduced wear and tear, and better performance in drilling through hard materials. The method of manufacturing the drill bit involves heating a mold and using a machineable matrix material to create a single piece bit with a smooth transition between the body and the upper portion.

Problems solved by technology

While bits that have abrasive polycrystalline diamond cutting elements are known to be effective in some formations, they have been found to be less effective for hard, very abrasive formations such as sandstone.

The slurry must travel across the top of the rib before reentering the fluid paths, which contributes to wear of the supporting material.

It is necessary that the threaded pin be made of steel because although the matrix material used to form the bit body has higher wear and erosion resistance as compare to steel, it is relatively hard and not easily machined.

Although it is well known in the art to weld a threaded pin, and optionally a stabilizer sleeve, to the bit body and steel shank in order to facilitate connection of the drill bit to the drill string, a discontinuous transition may result in premature bit failure due to internal stresses due to material mismatch which can lead to internal cracking and / or cracking when high loading is applied.

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