CN112922533A

CN112922533A - PDC drill bit with cutting structure and combination method

Info

Publication number: CN112922533A
Application number: CN202110006915.3A
Authority: CN
Inventors: 陈洋; 朱金南; 何进; 周长清; 蒲杰; 邓力山; 杨斌; 权勇
Original assignee: Better Oilfield Technology Co ltd
Current assignee: Better Oilfield Technology Co ltd
Priority date: 2021-01-05
Filing date: 2021-01-05
Publication date: 2021-06-08

Abstract

The invention relates to a PDC drill bit with a cutting structure, which comprises a PDC drill bit, wherein a plurality of cutting teeth are arranged at the same position of the crown part of the PDC drill bit in a tooth arrangement mode, the PDC drill bit comprises a drill bit base body welded on the drill bit in a coating mode and a plurality of blades arranged on the surface of the drill bit base body, a PDC composite sheet is embedded on the drill bit base body, the blades are provided with a plurality of triangular teeth and three-fork teeth, at least two blades are also provided with a plurality of chisel-shaped PDC cutting teeth, the triangular teeth and the three-fork teeth are arranged in the front row of the blades, the chisel-shaped PDC cutting teeth are arranged in the rear row of the blades, a chip discharge groove is arranged at the gap between every two adjacent blades, and a plurality of. The invention can solve the problems of low cutting efficiency, serious breakage and abrasion of cutting teeth, short service life and the like of the conventional PDC drill bit for drilling in the gravel-containing sandstone stratum at present.

Description

PDC drill bit with cutting structure and combination method

Technical Field

The invention relates to the technical field of oil drilling tools, in particular to a PDC drill bit with a cutting structure and a combination method.

Background

In recent years, as drilling technology has evolved, fields have continually challenged deeper, more complex formations. Heterogeneous and highly abrasive formations are often encountered in oil and gas drilling operations under complex geological conditions, and thus improving the drilling efficiency of these formations becomes an important way to shorten the drilling cycle and reduce the economic cost. The performance of the drill bit as a main rock breaking tool for petroleum drilling directly influences the drilling efficiency.

In the Marhu area of Xinjiang oil field in China, the stratums of the Clarityi group, Baikou spring group and the Wuerry group mainly comprise gravels and mudstones, the particle size of the gravels is 10-50mm, the quartz content is up to 90%, the stratum has extremely strong abrasiveness and poor drillability, and the blocks mainly comprise horizontal drilling wells, the average section length of the blocks is about 1500m, and the method is a great challenge to the service life of a drill bit; quartz sandstone strata also exist in the stratum of the Behcet river group of the Sichuan oil field and the Paschiki kirschner group constructed in the mountain front of the Tarim oil field, and have high hardness and strong abrasiveness; when the roller bit drills a stratum, the conditions of tooth breakage, tooth abrasion, bit reducing, bearing failure and the like are easy to occur, and finally the roller bit is scrapped, so that the characteristics of small bit entering size and low mechanical drilling speed are shown; the conventional PDC drill bit adopts cylindrical PDC cutting teeth as cutting elements which are mainly used for soft to medium hard strata, but the conventional PDC drill bit has poor adaptability in high-abrasive strata of gravel-containing sandstone, and is easy to have the conditions of tooth breakage, serious abrasion and the like. Severely restricting the development efficiency and increasing the drilling cost. Therefore, it is necessary to design a composite cutting structure PDC bit.

An effective solution to the problems in the related art has not been proposed yet.

Disclosure of Invention

The invention aims to provide a PDC drill bit with a cutting structure and a combination method, which are used for overcoming the problems in the prior art, and the PDC drill bit with the combined cutting structure is provided, so that the problems of low cutting efficiency, serious chipping and abrasion of cutting teeth, short service life and the like in the conventional PDC drill bit for drilling in a gravel sandstone stratum can be solved.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a cutting structure PDC drill bit, includes the PDC drill bit, adopts plural cloth tooth mode and has arranged many cutting teeth in PDC drill bit crown same position, the PDC drill bit is in including applying the drill bit base body and the setting of welding at the drill bit the a plurality of wing on drill bit base body surface, it has the compound piece of PDC to inlay on the drill bit base body, the wing is provided with three arriss teeth of a plurality of and three arriss teeth and two at least wings still set up a plurality of chisel shape PDC cutting teeth, three arriss teeth and three-arriss teeth setting are at the antecedent of wing, chisel shape PDC cutting teeth setting is at the back row of wing, and is adjacent the clearance department of wing is equipped with the chip groove, the chip groove is equipped with a plurality of nozzles.

Further, the cutting teeth positions of two adjacent blades or two blades distributed at intervals are the same or the cutting teeth positions of three adjacent blades or three blades distributed at intervals are the same.

Furthermore, the PDC drill bit adopts the combination of triangular teeth and three trident teeth to lay the tooth mode, is located triangular teeth are arranged to the core of PDC drill bit, and three prong is arranged to the nasal part and the outer shoulder of PDC drill bit.

Furthermore, triangular teeth and three-fork teeth are respectively arranged on the two blades, and the triangular teeth and the three-fork teeth are arranged on the same blade in a staggered mode.

Furthermore, the triangular teeth are composed of three convex ridges, the included angle alpha of each ridge ranges from 45 degrees to 120 degrees, one ridge is located on the center line of the tooth, two sides of each ridge are respectively provided with one ridge, the distance D between the ridge on the two sides and the center ranges from (1/3-1/2) D, and D is the diameter of the cutting tooth.

Furthermore, the three-prong is composed of three triangular ridges and a spherical surface, the spherical surface parts of the three triangular ridges are uniformly arranged, the radius SR of the spherical surface is 20-40mm, the triangular ridges adopt an inward concave design or an outward convex design, the included angle delta of the ridges in the inward concave design is 120-140 degrees, the beta angle formed between the ridges and the plane is 2-5 degrees, the included angle theta of the ridges in the outward convex design is 140-165 degrees, and the gamma angle formed between the ridges and the plane is 2-5 degrees.

Furthermore, the chisel-shaped PDC cutting tooth is a combination of a middle arc surface and two side inclined planes, wherein the radius of the middle arc surface is 15-30mm, the width d2 is 1.5-3.0mm, and the included angle of the two side inclined planes is 90-120 degrees.

Further, the method for combining the PDC drill bit with the cutting structure comprises a method for combining a 2-level cutting structure of a PDC composite sheet and a chisel-type PDC cutting tooth, or a method for combining a 2-level cutting structure of a PDC composite sheet and a diamond impregnated insert, or a method for combining a 3-level cutting structure of a PDC composite sheet, a chisel-type PDC cutting tooth and a diamond impregnated insert.

Further, the PDC drill bit comprises a 1 st-level chisel PDC cutting tooth, a 2 nd-level chisel PDC cutting tooth and a 3 rd-level diamond pregnant insert, wherein the 2 nd-level chisel PDC cutting tooth is lower in cutting height by 0.5-1.5mm than the 1 st-level chisel PDC cutting tooth, the 3 rd-level diamond pregnant insert is lower in cutting height by 1.0-2.0mm than the 2 nd-level chisel PDC cutting tooth, and the 2 nd-level chisel PDC cutting teeth are at least distributed on two blades and arranged in the same track with the 1 st-level chisel PDC cutting tooth.

Further, the 3-stage cutting structure is formed by adopting impregnated diamond blocks in a mode of mixing and preparing large-particle diamond and small-particle diamond, wherein 18/20 is selected as the large-particle diamond, 25/35 is selected as the small-particle diamond, and the diamond concentration is 100% -150%.

Compared with the prior art, the invention has the following beneficial effects:

1) the invention provides a PDC drill bit with a combined cutting structure, which can solve the problems of low cutting efficiency, severe cutting tooth breakage and abrasion, short service life and the like of drilling in a high-abrasiveness stratum containing gravel and quartz sandstone by using a conventional PDC drill bit at present; 2) the invention has simple structure and novel design.

Drawings

FIG. 1 is a schematic diagram of a PDC bit having a cutting structure according to the present invention;

FIG. 2 is a top view of a cutting structure PDC bit of the present invention;

FIG. 3 is a diagram of a plurality of teeth arrangement of a PDC bit having a cutting structure according to the present invention;

FIG. 4 is a blade configuration view of a PDC bit having a cutting structure in accordance with the present invention;

FIG. 5 is a blade configuration view of a PDC bit having a cutting configuration in accordance with the present invention;

FIG. 6 is a three-edged tooth structure diagram of a PDC bit with a cutting structure according to the present invention;

FIG. 7 is a schematic diagram of the cutting function of the triangular teeth of the PDC drill bit with the cutting structure according to the present invention;

FIG. 8 is a schematic view of a triangular land recess of a PDC bit having a cutting structure in accordance with the present invention;

FIG. 9 is a view of a convex triangular ridge structure of a PDC bit having a cutting structure according to the present invention;

FIG. 10 is a cutting structure view of a cutting structure PDC bit of the present invention;

FIG. 11 is a diagram of a chisel PDC cutter of a cutting structure PDC drill bit of the present invention;

FIG. 12 is a diagram of a diamond impregnated block of a PDC bit having a cutting structure in accordance with the present invention.

FIG. 13 is a schematic diagram of a level 1 primary cutting structure of the present invention for breaking rock in a subterranean formation;

FIG. 14 is a schematic diagram of a level 2 primary cutting structure of the present invention for breaking rock in a subterranean formation;

FIG. 15 is a schematic diagram of a 3-stage main cutting structure according to the present invention for breaking rock in a formation.

In the figure, 1, a drill bit base body, 2, blades, 3, triangular teeth, 4, three fork teeth, 5, chisel-shaped PDC cutting teeth, 6, chip grooves, 7, a nozzle, 8, a PDC composite sheet, 9, three fork teeth, 10, three fork teeth, 11, triangular ridges, 12, a spherical surface, 13, a diamond impregnated insert, 14, an intermediate cambered surface and 15 inclined planes.

Detailed Description

The invention will be further described with reference to the following detailed description and the accompanying drawings:

as shown in fig. 1-2, a cutting structure PDC drill bit, including the PDC drill bit, adopt plural cloth tooth mode and arranged many cutting teeth in PDC drill bit crown same position, the PDC drill bit is in including applying drill bit base member 1 and the setting of welding at the drill bit a plurality of wing 2 on drill bit base member 1 surface, it has PDC composite piece 8 to inlay on the drill bit base member 1, wing 2 is provided with a plurality of triangular teeth 9 and trident 10 and at least two wing 2 still set up a plurality of chisel shape PDC cutting teeth 5, triangular teeth 9 and trident 10 set up the front bank at wing 2, chisel shape PDC cutting teeth 5 set up the back row at wing 2, and are adjacent the clearance department of wing 2 is equipped with chip groove 6, the chip groove is equipped with a plurality of nozzles 7.

A plurality of teeth arrangement modes (as shown in fig. 3) are adopted, one: 2-3 cutting teeth are arranged at the same radius position on the crown part of the drill bit, so that the abrasion resistance of the cutting teeth can be improved, and the second step is as follows: the larger value of Rh1 formed at the bottom of the well is larger than the ridge Rh2 formed by odd distributed teeth, so that the resistance of the drill bit to the center deviation at the bottom of the well is larger, and the stability is better.

In accordance with the foregoing, the cutting tooth positions of two blades distributed adjacent (as shown in fig. 4 where BLD1 and BLD2 repeat) or spaced apart (as shown in fig. 5 where BLD1 and BLD4 repeat) are the same or the cutting tooth positions of three blades distributed adjacent (as shown in fig. 4 where BLD1, BLD2, and BLD3 repeat) or spaced apart (as shown in fig. 5 where BLD1, BLD3, and BLD5 repeat) are the same.

According to the content, the PDC drill bit adopts a tooth arrangement mode combining the triangular teeth 9 and the three-fork teeth 10, the triangular teeth 9 are arranged in the core of the PDC drill bit, and the three-fork teeth 10 are arranged on the nose part and the outer shoulder of the PDC drill bit.

According to the content, the triangular teeth 9 and the three-fork teeth 10 are respectively arranged on the two blades 2, and the triangular teeth 9 and the three-fork teeth 10 on the same blade are arranged in a staggered mode at intervals.

According to the above, the triangular tooth 9 is composed of three convex ridges 11, the included angle α of the ridges 11 is 45-120 degrees, one ridge 11 is located on the tooth center line, two ridges 11 are respectively arranged on two sides, the distance D between the ridge 11 on two sides and the center is (1/3-1/2) D (as shown in fig. 6), and D is the diameter of the cutting tooth.

The protruding ridges of the triangular teeth 9 can pre-crush the stratum and release the stratum stress, and the ridges in the middle and the ridges on two sides have certain height difference so that the stratum has the function of graded cutting (as shown in fig. 7). When the drill meets the hard interlayer and the depth of the drill into the stratum is H1, only the middle ridge plays a role in ploughing and cutting the stratum; when the drill meets the soft interlayer and is eaten into the stratum to a depth of H2, the three edges simultaneously play a role in ploughing and cutting the stratum, and the rock breaking efficiency is greatly improved.

According to the content, the three-prong 9 is composed of three triangular ridges 11 and a spherical surface 12, the spherical surface parts of the three triangular ridges 11 are uniformly arranged, the radius SR of the spherical surface 12 takes a value of 20-40mm, the triangular ridges 11 adopt an inward concave design or an outward convex design, the included angle delta of the ridges during the inward concave design takes a value of 120-140 degrees, the beta angle formed with the plane takes a value of 2-5 degrees, the included angle theta of the ridges during the outward convex design takes a value of 140-165 degrees, and the gamma angle formed with the plane takes a value of 2-5 degrees.

The three-prong 9 consists of three triangular ridges 11 and a ball 12 surface, the three triangular ridges 11 are uniformly distributed, the radius SR of the middle spherical surface is 20-40mm, and the spherical surface 12 structure can disperse stress and greatly improve the shock resistance; when the formation hardness is small and homogeneous, and the drillability is good, the triangular ridge 11 is designed to be concave inwards (as shown in figure 8), the included angle delta of the ridge is 120-140 degrees, and the beta angle formed by the included angle delta and the plane is 2-5 degrees, namely the cutting tooth reduces the anteversion angle (as shown in figure 10), so that the cutting tooth has stronger attack force and high cutting efficiency; when the stratum has high hardness, contains gravels, is inhomogeneous and has poor drillability, the triangular ridge 11 is designed to be convex outwards (as shown in figure 9), the included angle theta of the ridge is 140-165 degrees, and the included angle gamma of the ridge and the plane is 2-5 degrees, namely the cutting tooth increases the front rake angle (as shown in figure 10), so that the cutting tooth has better impact resistance and can prolong the service life of the drill bit.

According to the content, the chisel PDC cutting tooth 5 is a combination of the middle cambered surface 14 and the two side inclined planes 15, wherein the radius of the middle cambered surface 14 is 15-30mm, the width d2 is 1.5-3.0mm, and the included angle of the two side inclined planes 15 is 90-120 degrees.

According to the content, the combined method of the cutting structure PDC drill bit comprises a combined method of a 2-level cutting structure adopting the PDC composite sheet 8+ the chisel-type PDC cutting tooth 5 or a 2-level cutting structure adopting the PDC composite sheet 5+ the diamond pregnant insert 13 or a 3-level cutting structure adopting the PDC composite sheet 8+ the chisel-type PDC cutting tooth 5+ the diamond pregnant insert 13.

In the earlier stage of using the bit, the 1-level cutting structure breaks the rock of the stratum (as shown in figure 13), when the 1-level cutting teeth are worn to a certain degree, the 2-level cutting structure starts to break the rock of the stratum (as shown in figure 14), and when the 1-level cutting teeth and the 2-level cutting structures are further worn to a certain degree, the 3 rd-level cutting structure starts to break the rock of the stratum (as shown in figure 15), so that the aims of enhancing the wear resistance of the PDC bit and improving the biting capacity of the PDC bit can be achieved.

The combined cutting structure PDC drill bit, the 2 nd level main cutting structure adopts chisel-shaped PDC cutting teeth. The method has the following advantages: compared with the conical teeth, the diamond area is larger, and the wear resistance can be improved; the advantages are as follows: reducing lateral vibration and bit whirl; the advantages are three: the cambered surface structure has strong impact resistance, and can protect front row teeth in a soft and hard staggered stratum.

As described above, as shown in fig. 11 and 12, the PDC drill bit includes the 1 st-stage chisel PDC cutter 5, the 2 nd-stage chisel PDC cutter 5, and the 3 rd-stage diamond impregnated insert 13, wherein the 2 nd-stage chisel PDC cutter 5 is lower in cutting height by 0.5 to 1.5mm than the 1 st-stage chisel PDC cutter 5, and the 3 rd-stage diamond impregnated insert 13 is lower in cutting height than the 2 nd-stage chisel PDC cutter 5. 1.0-2.0mm, the 2 nd level chisel PDC cutters 5 are distributed over at least two blades 2 and co-track with the 1 st level chisel PDC cutters 5.

According to the content, the 3-stage cutting structure is formed by adopting the diamond-impregnated block 13 in a mode of mixing and preparing large-particle diamond and small-particle diamond, wherein 18/20 is selected as the large-particle diamond, 25/35 is selected as the small-particle diamond, and the diamond concentration is 100% -150%.

The combined cutting structure PDC drill bit, 3 rd level main cutting structure adopts impregnated diamond (as shown in figure 12), and it uses natural diamond as abrasive, adopts the mode of mixing and preparing large-granule diamond 17 and small-granule diamond 16, has extremely high hardness and wear resistance, can effectively improve rock breaking efficiency and service life.

In conclusion, the invention has the advantages that the problems in the prior art are overcome, and the PDC drill bit with the combined cutting structure is provided, so that the problems of low cutting efficiency, serious cutting tooth breakage and abrasion, short service life and the like in the conventional PDC drill bit for drilling in the gravel-quartz sandstone high-abrasiveness stratum at present can be solved.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that various changes, modifications and substitutions can be made without departing from the spirit and scope of the invention as defined by the appended claims. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a cutting structure PDC drill bit, a serial communication port, includes the PDC drill bit, adopts plural cloth tooth mode and has arranged many cutting teeth in PDC drill bit crown same position, the PDC drill bit is in including applying the drill bit base member and the setting of welding at the drill bit a plurality of wing on drill bit base member surface, it has the compound piece of PDC to inlay on the drill bit base member, the wing is provided with three arriss teeth of a plurality of and trident tooth and two at least wings still set up a plurality of chisel shape PDC cutting teeth, three arriss teeth and trident tooth setting are at the antecedent of wing, chisel shape PDC cutting tooth setting is at the back row of wing, and is adjacent the clearance department of wing is equipped with the chip groove, the chip groove is equipped with a plurality of nozzles.

2. The cutting structure PDC bit of claim 1, wherein the cutter positions of two adjacent or spaced blades are the same or the cutter positions of three adjacent or spaced blades are the same.

3. The PDC bit of claim 1 wherein the PDC bit is a combination of a tri-tooth and a tri-tooth arrangement, the tri-tooth is disposed in a core of the PDC bit, and the tri-tooth is disposed in a nose and an outer shoulder of the PDC bit.

4. The cutting structure PDC bit of claim 1, wherein the two blades are respectively provided with triangular teeth and three-pointed teeth and the triangular teeth and the three-pointed teeth are alternately arranged on the same blade.

5. The PDC bit of claim 4 wherein the triangular tooth is formed by three raised ridges having an included angle α of 45-120 degrees, one ridge being located on a tooth centerline, one ridge being disposed on each side, and the distance D between the ridge on each side and the center being (1/3-1/2) D, where D is the diameter of the cutting tooth.

6. The PDC bit of claim 4, wherein the three-prong is composed of three triangular ridges and a spherical surface, the spherical surface portions of the three triangular ridges are uniformly arranged, the spherical radius SR is 20-40mm, the triangular ridges adopt an inward concave design or an outward convex design, the included angle delta of the inward concave design ridges is 120-140 degrees, the included angle beta with the plane is 2-5 degrees, the included angle theta of the outward convex design ridges is 140-165 degrees, and the included angle gamma with the plane is 2-5 degrees.

7. The cutting structure PDC bit of claim 1, wherein the chisel PDC cutters are a combination of a medial camber having a radius of 15-30mm and a lateral rake surface having a width d2 of 1.5-3.0mm, the lateral rake surface having an included angle of 90-120 degrees.

8. The method for combining the PDC drill bit with the cutting structure is characterized by comprising a method for combining a 2-stage main cutting structure comprising a PDC composite sheet and a chisel-type PDC cutting tooth, or a method for combining a 2-stage main cutting structure comprising a PDC composite sheet and a diamond impregnated insert, or a method for combining a 3-stage main cutting structure comprising a PDC composite sheet, a chisel-type PDC cutting tooth and a diamond impregnated insert.

9. The cutting structure PDC bit combination of claim 8, wherein the PDC bit comprises a level 1 chisel PDC cutter, a level 2 chisel PDC cutter, and a level 3 diamond impregnated insert, the level 2 chisel PDC cutter having a cutting height 0.5 to 1.5mm lower than the level 1 chisel PDC cutter, the level 3 diamond impregnated insert having a cutting height 1.0 to 2.0mm lower than the level 2 chisel PDC cutter, the level 2 chisel PDC cutter being distributed over at least two blades and co-tracking with the level 1 chisel PDC cutter.

10. The method of claim 8 wherein the 3-stage cutting structure is formed using diamond impregnated blocks of diamond in a mixed formulation of large and small diamond particles, wherein the large diamond particles are selected from 18/20 and the small diamond particles are selected from 25/35, and wherein the diamond concentration is 100% to 150%.