CN109854177B

CN109854177B - Mechanical adjustable multifunctional PDC drill bit

Info

Publication number: CN109854177B
Application number: CN201910046087.9A
Authority: CN
Inventors: 田家林; 胡学华; 杨敏敏; 高宏博; 何虹志; 杨应林; 杨毅
Original assignee: Southwest Petroleum University
Current assignee: Southwest Petroleum University
Priority date: 2019-01-17
Filing date: 2019-01-17
Publication date: 2020-09-29
Anticipated expiration: 2039-01-17
Also published as: CN109854177A

Abstract

The invention relates to a mechanical type adjustable multifunctional PDC drill bit which comprises an upper joint, a body and a drill bit body. The upper connector is connected to the upper end of the body through threads, the bit body is connected to the lower end of the body through threads, when high-pressure drilling fluid enters a cavity between the upper end of the indexing mechanism and the inner cylinder from a circumferential hole in the middle of the anti-drop ring, the indexing mechanism moves downwards under the action of the pressure of the drilling fluid, when the circumferential hole in the lower portion of the indexing mechanism is connected with a radial channel hole in the bit body, the high-pressure drilling fluid enters a cavity between the bit body and the lower piston, the lower piston moves downwards under the action of the hydraulic force of the drilling fluid to further push the rotary blades to rotate outwards around the pins, when the rotary blades are closed, the drill bit can achieve a diameter protection function, and when the rotary blades are opened, the drill bit achieves a reaming. The mechanical-control multifunctional PDC drill bit can improve the drilling efficiency and is suitable for ensuring the normal drilling operation under the condition of irregular well bore or diameter reduction of the well bore.

Description

Mechanical adjustable multifunctional PDC drill bit

Technical Field

The invention relates to a mechanical regulation and control multifunctional PDC drill bit for oil and natural gas exploitation operation, which is particularly suitable for the conditions of irregular well bore, reduced well bore diameter or serious abrasion of the PDC drill bit.

Background

At present, PDC bits have become a common product of drilling engineering in the world, and roller cone bits have become special bits. The U.S. department of energy has identified PDC bits as the primary means of increasing rates of penetration. The PDC drill bit is highly valued for use in various oil fields, and the PDC drill bit for deep wells and ultra-deep wells is used as a main way for improving the drilling speed. When the PDC drill bit drills in a soft-medium hard rock stratum, the drilling efficiency is far higher than that of an impregnated drill bit and a roller bit. While creating good economic benefits, PDC bits also have exposed many problems, mainly manifested by low bit life and slow drilling speed in complex formations and formations above medium-hard.

The role of drilling in oilfield development is very important, and it is estimated that in some oilfield investment developments, the drilling investment accounts for 35% to 40%. At present, the oil resources of countries in the world are gradually exhausted, which requires drilling companies to develop oil more economically and efficiently. The working performance of a drill bit, which is the most important tool in drilling operations, directly affects the quality, cost and efficiency of the drilling operation. In order to reduce the drilling cost of the whole well and improve the drilling speed, the PDC drill bit technology receives great attention in main drill bit enterprises in the world, the investment in the aspects of research personnel, research and development cost and the like is increased, the level of the research personnel is also greatly improved, a plurality of novel upgraded PDC drill bits are developed, and the quality and the like are better. At present, PDC drill bits are widely used in various engineering fields such as oil exploration and geological exploration, and have important significance for improving drilling technologies of various countries. PDC bits will find increasing use in oil production operations in the future. Therefore, further research on the PDC drill bit has important significance for improving the oil and gas exploitation efficiency in China.

Disclosure of Invention

In order to solve the problems of improving the drilling efficiency and prolonging the service life of a drill bit in the oil and gas development drilling process in the background technology, the invention provides a mechanical type regulated multifunctional PDC drill bit. When the PDC drill bit works, high-pressure drilling fluid enters a cavity between the upper end of the indexing mechanism and the inner cylinder from a circumferential hole in the middle of the anti-drop ring, the indexing mechanism is opened and moves downwards under the action of the pressure of the drilling fluid, when the circumferential hole in the lower portion of the indexing mechanism is connected with a radial channel hole in the drill bit body, the high-pressure drilling fluid enters the cavity between the drill bit body and the lower piston, the lower piston is started and moves downwards under the action of the drilling fluid pressure, the rotary blades are pushed to rotate outwards around the pins, when the rotary blades are closed, the drill bit can achieve a diameter protection function, when the rotary blades are opened, the drill bit achieves an reaming function, and then under the rotation action of a drill column, the rotary blades obtain enough torque, so that rock can be broken by rotating along with the drill bit.

The technical scheme of the invention is as follows: the mechanical type regulation and control multifunctional PDC drill bit comprises an upper connector, a body and a drill bit body, wherein the upper connector is connected to the upper end of the body through threads, and the drill bit body is connected to the lower end of the body through threads; the body comprises an outer cylinder, an anti-drop ring, an inner cylinder, a sealing ring a, a pin a, a shifting mechanism, a spring a and a sealing ring b, wherein the anti-drop ring is arranged between the lower end face of an upper joint and the upper end face of the inner cylinder; a sealing ring c, a sealing block a, a welding block, a lower piston, a sealing block b, a spring b, a pin b and a rotary blade are sequentially arranged on the drill bit body from top to bottom, the welding block is fixed on the drill bit body through welding, and the pin b is fixed on the drill bit body through welding; the rotary blade is arranged at the blade position of the bit body through a pin b, the rotary blade can rotate around the pin b under the pushing of the lower piston, and a spring b is arranged at the lower end of the lower piston; 5 axial channel holes are uniformly distributed in the upper part of the bit body along the circumferential direction, 5 radial channel holes are formed in the positions corresponding to the axial channel holes, a sealing block a, a lower piston, a sealing block b and a spring b are sequentially arranged in the axial channel holes from top to bottom, and the sealing block a is arranged on the upper part of the bit body in an interference fit manner; when the mechanical type adjustable multifunctional PDC drill bit works, high-pressure drilling fluid enters a cavity between the upper end of the indexing mechanism and the inner cylinder from a circumferential hole in the middle of the anti-drop ring, the indexing mechanism is opened and moves downwards under the action of drilling hydraulic pressure, when the circumferential hole in the lower part of the indexing mechanism is connected with a radial channel hole in the drill bit body, the high-pressure drilling fluid enters the cavity between the drill bit body and the lower piston, the lower piston is started and moves downwards under the action of the drilling hydraulic pressure, the rotary blades are further pushed to rotate outwards around the pins b, when the rotary blades are closed, the drill bit can realize a diameter protection function, and when the rotary blades are opened, the drill bit can realize a reaming function; the upper part and the lower part of the indexing mechanism are respectively provided with a sealing ring a; 4 circumferential holes are uniformly distributed in the middle of the anti-falling ring along the circumferential direction, and the circumferential holes are circular holes; 5 circumferential holes are uniformly distributed in the lower part of the indexing mechanism along the circumferential direction, the circumferential holes are round holes, and the round holes of the indexing mechanism are larger than radial channel holes in the bit body; one rotary blade is mounted at each blade position of the bit body, and PDC cutters are mounted on the rotary blades.

The invention has the beneficial effects that: (1) the PDC drill bit can realize the control of the opening angle of the rotary cutter wing by controlling the pressure of the drilling fluid according to the operation requirement, and efficiently and reliably realize the gauge protection and reaming functions of the drill bit; (2) the diameter of a circumferential hole of the indexing mechanism is larger than that of a radial channel hole on the bit body, so that when the pressure of drilling fluid is reduced and the upper piston moves upwards under the action of the elastic force of the spring a, the drilling fluid in the radial channel hole on the bit body can be discharged smoothly, and the rotary blade can be ensured to be withdrawn smoothly.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1 in accordance with the present invention;

FIG. 3 is a cross-sectional view B-B of FIG. 1 of the present invention;

FIG. 4 is a cross-sectional view taken at C-C of FIG. 1 of the present invention;

fig. 5 is a cross-sectional view D-D of fig. 1 of the present invention.

In the figure: 1. the tool comprises an upper connector, 2, an outer cylinder, 3, an anti-drop ring, 4, an inner cylinder, 5, sealing rings a and 6, a pin a and 7, an indexing mechanism, 8, a spring a and 9, a sealing ring b and 10, a bit body, 11, a sealing ring c and 12, sealing blocks a and 13, a welding block, 14, a lower piston, 15, sealing blocks b and 16, a spring b and 17, a pin b and 18 and a rotary blade.

Detailed Description

The invention will be further described with reference to the accompanying drawings in which:

referring to the attached figure 1, the mechanically regulated multifunctional PDC drill bit comprises an upper connector 1, a body and a bit body 10, wherein the upper connector 1 is connected to the upper end of the body through threads, and the bit body 10 is connected to the lower end of the body through threads; the body comprises an outer cylinder 2, an anti-drop ring 3, an inner cylinder 4, a sealing ring a5, a pin a6, an indexing mechanism 7, a spring a8 and a sealing ring b9, wherein the anti-drop ring 3 is arranged between the lower end face of an upper joint 1 and the upper end face of the inner cylinder 4, the inner cylinder 4 is connected with the outer cylinder 2 through the pin a6, the tail end of the pin a6 extends into an outer wall groove of the indexing mechanism 7 to control the limit displacement of the indexing mechanism 7, and the spring a8 is arranged between the lower part of the indexing mechanism 7 and a step face of the lower part of the outer cylinder 2; a sealing ring c11, a sealing block a12, a welding block 13, a lower piston 14, a sealing block b15, a spring b16, a pin b17 and a rotary blade 18 are sequentially arranged on the bit body 10 from top to bottom, the welding block 13 is fixed on the bit body 10 through welding, and the pin b17 is fixed on the bit body 10 through welding; rotary blades 18 are mounted on the blade positions of the bit body 10 through a pin b17, the rotary blades 18 can rotate around a pin b17 under the pushing of the lower piston 14, and a spring b16 is mounted at the lower end of the lower piston 14; 5 axial channel holes are uniformly distributed in the upper part of the bit body 10 along the circumferential direction, 5 channel holes are formed in the radial position corresponding to the axial channel holes, a sealing block a12, a lower piston 14, a sealing block b15 and a spring b16 are sequentially arranged in the axial channel holes from top to bottom, and the sealing block a12 is arranged on the upper part of the bit body 10 in an interference fit manner; the upper part and the lower part of the indexing mechanism 7 are respectively provided with a sealing ring a 5; 4 circumferential holes are uniformly distributed in the middle of the anti-falling ring 3 along the circumferential direction, and are round holes; 5 circumferential holes are uniformly distributed in the lower part of the indexing mechanism 7 along the circumferential direction, the circumferential holes are round holes, and the round holes of the indexing mechanism 7 are larger than radial channel holes in the bit body 10; one rotary blade 18 is mounted at each blade location of the bit body 10, and PDC cutters are mounted on the rotary blades 18.

When the mechanical type adjustable multifunctional PDC drill bit works, high-pressure drilling fluid enters a cavity between the upper end of the indexing mechanism 7 and the inner cylinder 4 from a circumferential hole in the middle of the anti-drop ring 3, under the action of drilling hydraulic pressure, the indexing mechanism 7 is opened and moves downwards, when a circumferential hole at the lower part of the indexing mechanism 7 is connected with a radial passage hole on the bit body 10, high-pressure drilling fluid enters a cavity between the bit body 10 and the lower piston 14, under the action of the drilling hydraulic pressure, the lower piston 14 is actuated and moves downward, thereby pushing the rotary blades 18 to rotate outward about the pins b17, and when the rotary blades 18 are closed, the drill bit can realize the gauge protection function, when the rotary blades 18 are opened, the drill bit can realize the reaming function, the rotary blades then acquire a torque sufficient to rotate the breaking bit with the drill bit, under the action of the rotation of the drill string.

Claims

1. Mechanical type regulation and control's multi-functional PDC drill bit, its characterized in that: the mechanical-control multifunctional PDC drill bit comprises an upper connector (1), a body and a drill bit body (10), wherein the upper connector (1) is connected to the upper end of the body through threads, and the drill bit body (10) is connected to the lower end of the body through threads; the anti-falling connector comprises a body and a connector body, wherein the body comprises an outer barrel (2), an anti-falling ring (3), an inner barrel (4), a sealing ring a (5), a pin a (6), a transposition mechanism (7), a spring a (8) and a sealing ring b (9), the anti-falling ring (3) is arranged between the lower end face of an upper connector (1) and the upper end face of the inner barrel (4), the inner barrel (4) is connected with the outer barrel (2) through the pin a (6), the tail end of the pin a (6) extends into an outer wall groove of the transposition mechanism (7) to control the limit displacement of the transposition mechanism (7), and the spring a (8) is arranged between the lower part of the transposition mechanism (7) and the step face of the lower part of; a sealing ring c (11), a sealing block a (12), a welding block (13), a lower piston (14), a sealing block b (15), a spring b (16), a pin b (17) and a rotary blade (18) are sequentially arranged on the bit body (10) from top to bottom, the welding block (13) is fixed on the bit body (10) through welding, and the pin b (17) is fixed on the bit body (10) through welding; the rotary blade (18) is arranged at the blade position of the bit body (10) through a pin b (17), the rotary blade (18) can rotate around the pin b (17) under the pushing of the lower piston (14), and a spring b (16) is arranged at the lower end of the lower piston (14); 5 axial channel holes are uniformly distributed in the upper part of the bit body (10) along the circumferential direction, 5 radial channel holes are formed in the positions corresponding to the axial channel holes, a sealing block a (12), a lower piston (14), a sealing block b (15) and a spring b (16) are sequentially arranged in the axial channel holes from top to bottom, and the sealing block a (12) is arranged on the upper part of the bit body (10) in an interference fit manner; when the mechanical type adjustable multifunctional PDC drill bit works, high-pressure drilling fluid enters a cavity between the upper end of the indexing mechanism (7) and the inner cylinder (4) from a circumferential hole in the middle of the anti-drop ring (3), the indexing mechanism (7) is opened and moves downwards under the action of drilling hydraulic pressure, when the circumferential hole in the lower portion of the indexing mechanism (7) is connected with a radial channel hole in the drill bit body (10), the high-pressure drilling fluid enters a cavity between the drill bit body (10) and the lower piston (14), the lower piston (14) is started and moves downwards under the action of the drilling hydraulic pressure, the rotary blades (18) are further pushed to rotate outwards around the pins b (17), when the rotary blades (18) are closed, the drill bit can achieve a diameter keeping function, and when the rotary blades (18) are opened, the drill bit can achieve an reaming function.

2. The mechanically modulated, multifunctional PDC drill bit of claim 1, wherein: the upper part and the lower part of the indexing mechanism (7) are respectively provided with a sealing ring a (5); 4 circumferential holes are uniformly distributed in the middle of the anti-falling ring (3) along the circumferential direction, and are round holes; 5 circumferential holes are uniformly distributed in the lower part of the indexing mechanism (7) along the circumferential direction, the circumferential holes are round holes, and the round holes of the indexing mechanism (7) are larger than radial channel holes in the bit body (10); one rotary blade (18) is mounted at each blade position of the bit body (10), and PDC cutters are mounted on the rotary blades (18).