CN111088949A

CN111088949A - Novel cone-PDC composite drill bit

Info

Publication number: CN111088949A
Application number: CN201911204048.3A
Authority: CN
Inventors: 高磊; 罗绪良; 胡友生; 郗海华
Original assignee: Tianjin Lilin Bit Co ltd
Current assignee: Tianjin Lilin Bit Co ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2020-05-01

Abstract

The invention relates to the technical field of stratum tunneling tools, in particular to a novel cone-PDC composite bit, which comprises a bit crown, a bit leg, a cone and a tricone bit, wherein the cone is connected with the bit leg through the axial diameter of the bit leg and rotates around the axial diameter of the bit leg; the bit leg is arranged outside the drill bit crown and is arranged at intervals with the blade; and a tricone bit is arranged at the center of the bit crown, and the vertical distance between the tricone bit and the cutting blades of the bit crown is more than or equal to 50 and less than or equal to 70 mm. The center of the novel cone-PDC composite drill bit is provided with the tricone drill bit, the PDC teeth in the prior art are replaced, and the rock breaking efficiency of the center part of the composite drill bit can be obviously improved, so that the drilling operation time can be shortened, the abrasion of the composite drill bit is reduced, and the service life of the composite drill bit is prolonged.

Description

Novel cone-PDC composite drill bit

Technical Field

The invention relates to the technical field of stratum tunneling tools, in particular to a novel cone-PDC composite drill bit.

Background

The drill bit is a rock breaking tool used to break rock during drilling to form a wellbore. At present, rock breaking tools with the widest application range in drilling construction are cone bits and PDC polycrystalline diamond compact bits.

Roller cone drill bits break rock primarily by impact, crushing and a small amount of scraping, and are primarily characterized by high weight on bit, low torque, and adaptability to the vast majority of rock. Different from rock breaking modes of roller bit, the PDC bit mainly breaks rock in a scraping mode, and in soft to medium-hardness rock, the PDC bit uses small bit pressure, large torque and large displacement to obtain higher mechanical drilling speed, lower drilling cost and shorter well building period, so the PDC bit is widely popularized and used in the well drilling process.

Along with the development of oil gas exploration and development towards deep wells and ultra-deep wells gradually, the hardness and plasticity of rocks are continuously increased, the drillability is deteriorated, the mechanical drilling speed of the roller bit and the PDC bit is slow, the service life is short, and the development requirements of the acceleration and the efficiency improvement of the current oil gas drilling can not be met. The roller cone-PDC composite bit put on the market in recent years combines the advantages of the roller cone bit and the PDC bit, and improves the mechanical drilling speed and the service life to a certain extent. However, the central part of the composite drill bit has low mechanical drilling speed and low rock breaking efficiency, and the composite sheet is easy to damage, so that the mechanical drilling speed and the service life of the whole composite drill bit are seriously influenced, and the drill bit is scrapped when the mechanical drilling speed and the service life of the whole composite drill bit are serious.

Disclosure of Invention

The invention aims to overcome the defects of the technology and provide a novel cone-PDC composite drill bit.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a novel roller cone-PDC composite bit, includes drill bit crown, bit leg, gear wheel and tricone bit, its characterized in that: the cone is connected with the cone leg through the cone leg axis diameter and rotates around the cone leg axis diameter; the bit leg is arranged outside the drill bit crown and is arranged at intervals with the blade; and a tricone bit is arranged at the center of the bit crown, and the vertical distance between the tricone bit and the cutting blades of the bit crown is more than or equal to 50 and less than or equal to 70 mm.

Preferably, the water hole nozzles on the tricone bit and the water hole nozzles on the bit crown are in the same plane.

Preferably, the water hole nozzles on the tri-cone drill bit and the blades on the bit crown are in the same plane.

Preferably, a through hole or an internal thread is arranged at the center of the drill bit crown.

Preferably, the tricone bit is fixed at the center of the bit crown by welding or screwing.

Preferably, the cone is placed radially outward of bit crown 2/3.

Preferably, the teeth on the roller cone correspond to the composite sheets on the blades and are higher than the composite sheets, and the distance higher than the composite sheets is not less than 1mm and not more than h and not more than 1.5 mm.

The invention has the advantages that 1, the center part of the novel cone-PDC composite drill bit is provided with the tricone drill bit to replace the PDC teeth in the prior art, and the rock breaking efficiency of the center part of the composite drill bit can be obviously improved, so that the drilling operation time can be shortened, the abrasion of the composite drill bit can be reduced, and the service life of the composite drill bit can be prolonged.

2. The vertical distance of the tricone bit arranged at the central part of the novel cone-PDC composite bit is 50-70 mm higher than the blades, the tricone bit cuts a stratum before the blades and the outer side cone of the composite bit, and the construction process of drilling first and then reaming is similar to the construction process of drilling first and then reaming, so that the torque can be further reduced, and the effect of improving the stability of the bit can be achieved.

3. The novel cone-PDC composite drill bit divides a hydraulic system into two groups, one group is arranged on the tricone, the other group is arranged on the drill bit crown, and the cone-PDC composite drill bit can fully utilize the two groups of stepped hydraulic systems to assist in rock breaking, rock debris cleaning, drill bit cooling and the like.

Drawings

FIG. 1 is a front view of the present invention;

FIG. 2 is a perspective view of the present invention;

wherein: 1. bit crown, 2, bit leg, 3, cone, 4, tricone bit, 12, blade, 13, bit crown upper nozzle, 41, cone bit upper nozzle.

Detailed Description

The following detailed description of the preferred embodiments will be made with reference to the accompanying drawings. Example 1:

as shown in fig. 1-2, a novel cone-PDC composite drill bit comprises a bit crown 1, a bit leg 2, a cone 3 and a tricone bit 4, wherein the cone 3 is connected with the bit leg 2 through a bit leg axis diameter and rotates around the bit leg axis diameter; the bit leg 2 is arranged outside the bit crown 1 and is arranged at intervals with the blade 12; the tricone bit 4 is arranged at the center of the bit crown 1, and the vertical distance between the tricone bit 4 and the cutting blades 12 of the bit crown 1 is more than or equal to 50 and less than or equal to 70 mm. The tricone bit 4 is fixed on the drill crown 1 through a through hole or a thread 14 in the middle of the drill crown 1. The nozzle 41 of the tricone bit is in the same plane with the nozzle 13 on the bit crown 1. The bit leg 2 and the roller cone 3 are welded outside the drill bit crown 2/3R through a matching groove arranged on the drill bit crown 1, teeth on the roller cone 3 are arranged between the composite sheets on the blades 12 and are higher than the composite sheets, and the distance higher than the composite sheets is not less than 1mm and not more than h and not more than 1.5 mm.

Example 2:

this example is substantially the same as example 1, except that: the water eye nozzles 41 on the tri-cone drill bit 4 and the blades 12 on the bit crown 1 are in the same plane and are arranged to help clean debris between the tri-cone drill bit 4 and the bit crown 1.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A novel roller cone-PDC composite bit is characterized in that: the cone bit comprises a bit crown, a bit leg, a cone and a tricone bit, wherein the cone is connected with the bit leg through the axial diameter of the bit leg and rotates around the axial diameter of the bit leg; the bit leg is arranged outside the drill bit crown and is arranged at intervals with the blade; and a tricone bit is arranged at the center of the bit crown, and the vertical distance between the tricone bit and the cutting blades of the bit crown is more than or equal to 50 and less than or equal to 70 mm.

2. The novel roller cone-PDC composite drill bit of claim 1 wherein: the water hole nozzles on the tricone bit and the water hole nozzles on the bit crown are in the same plane.

3. The novel roller cone-PDC composite drill bit of claim 1 wherein: the water hole nozzle on the tricone bit and the blades on the bit crown are in the same plane.

4. The novel roller cone-PDC composite drill bit of claim 1 wherein: the center of the drill bit crown is provided with a through hole or an internal thread.

5. The novel roller cone-PDC composite drill bit of claim 4 wherein: the tricone bit is fixed at the center of the bit crown in a welding mode or a threaded connection mode.

6. The novel roller cone-PDC composite drill bit of claim 1 wherein: the cone is positioned radially outward of bit crown 2/3.

7. The novel roller cone-PDC composite drill bit of claim 1 wherein: the teeth on the cone correspond to the composite sheets on the blades and are higher than the composite sheets, and the distance higher than the composite sheets is not less than 1mm and not more than h and not more than 1.5 mm.