CN205135429U - PDC drill bit with reinforcing orientation is nature controlled easily - Google Patents
PDC drill bit with reinforcing orientation is nature controlled easily Download PDFInfo
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- CN205135429U CN205135429U CN201521008823.5U CN201521008823U CN205135429U CN 205135429 U CN205135429 U CN 205135429U CN 201521008823 U CN201521008823 U CN 201521008823U CN 205135429 U CN205135429 U CN 205135429U
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- drill bit
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- cutting teeth
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- 230000003014 reinforcing effect Effects 0.000 title abstract 3
- 230000036346 tooth eruption Effects 0.000 claims abstract description 21
- 238000009966 trimming Methods 0.000 claims description 12
- 238000009499 grossing Methods 0.000 claims description 6
- 238000005728 strengthening Methods 0.000 claims description 5
- 230000002708 enhancing effect Effects 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 2
- 238000005553 drilling Methods 0.000 abstract description 25
- 238000000034 method Methods 0.000 abstract description 20
- 238000010276 construction Methods 0.000 abstract description 5
- 238000010030 laminating Methods 0.000 abstract 1
- 210000000515 tooth Anatomy 0.000 abstract 1
- 239000011435 rock Substances 0.000 description 23
- 238000010586 diagram Methods 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 239000003208 petroleum Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 210000004400 mucous membrane Anatomy 0.000 description 2
- UPLPHRJJTCUQAY-WIRWPRASSA-N 2,3-thioepoxy madol Chemical compound C([C@@H]1CC2)[C@@H]3S[C@@H]3C[C@]1(C)[C@@H]1[C@@H]2[C@@H]2CC[C@](C)(O)[C@@]2(C)CC1 UPLPHRJJTCUQAY-WIRWPRASSA-N 0.000 description 1
- 206010044565 Tremor Diseases 0.000 description 1
- 238000010009 beating Methods 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
- E21B10/54—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of the rotary drag type, e.g. fork-type bits
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
The utility model relates to a PDC drill bit with reinforcing orientation is nature controlled easily, including bit body, crown and cutting teeth, be provided with a plurality of cutting teeths on the outline line of crown, the bent profile of surface of crown of drill bit is formed by core, nasal part, the outside, shoulder and the section smooth connection of rule footpath in proper order, the drill bit core be the concave spherical surface, the cutting teeth that is close to bit body center department be the side cut tooth, and its cut edge with the point of intersect of excircle on the axis of bit body 1, the profile that the shoulder of drill bit corresponds be spherical surface structure, a rule directly section corresponding profile are cone structure. The utility model has the advantages of: the drill bit is in directional drilling and build -up process, and its core is better with the shaft bottom laminating, and the steering drag of core is all littleer with the frictional resistance who advises the footpath, orientation through the reinforcing drill bit is controlled the performance and is improved wall of a well quality, can reduce the skew degree of directional orbit to improve directional drilling's construction quality.
Description
Technical field
The utility model relates to the technical equipment fields such as oil-gas drilling engineering, mining, geological drilling, construction work, construction of tunnel, shield structure and no-dig technique, and particularly a kind of have the PDC drill bit strengthening directed easily control property.
Background technology
Along with society is to the increase of petroleum resources demand, the exploitation of the petroleum resources that occurrence condition is poor and Novel oil gas resource becomes inevitable, such as Deep Oil And Gas Exploration, shale gas, coal bed gas, Marine oil and gas resource etc.Under the condition of new petroleum resources exploitation, drillng operation faces new demand.In general, casing programme faces more far-reaching, more complicated situation; For well type, the technology such as directional well, horizontal well, Multilateral Wells are used in a large number.And inclination section is as the break-in position in these casing programmes, quality, the efficiency of its operation process have considerable influence for drilling cost, drilling time etc.
In deflecting the boring process, traditional PD C drill bit exists that deflecting curvature is excessive, bit wear is serious, the borehole wall is rough, often excessive, the actual path of bit freezing, deflecting frictional resistance comparatively planned course depart from the defects such as larger, this disagrees with the low cost instantly proposed, high efficiency drilling well theory.For this present situation, domestic and international many experts have carried out large quantity research to the variety of problems that drill bit occurs in deflecting the boring process.But great majority research all rests on the aspect such as drilling assembly and bent sub design, PDC drill bit heart portion shape is on the impact of deflecting the boring to rarely have comprehensive study to consider.
PDC drill bit is at sandstone and mudstone stratum rate of penetration is high, the bit operation life-span long, heat-resisting ability is better than rock bit, is applicable to directional well, horizontal well construction equally.Present PDC drill bit has become main force's drill bit of oil/gas drilling, but in directional well operation, often occurs the phenomenons such as kick off difficulty, orientation are unstable, drill bit movement tendency increases, footage per bit is slow.Affecting in PDC drill bit directional drilling power factor, the design feature of heart portion shape is particularly crucial.Whether successfully decide directional inclination, can the hold angle stage creep into by held stationary.As shown in Figure 5, existing PDC drill bit erects heart phenomenon relatively seriously, and deflecting easily controls poor-performing.It is in build-up process, creep into distance for h, angle is β, cutting teeth drilling process load (broken rock) directly determines the deflection capacity of drill bit with unloaded volume result, as shown in Figure 7, its drill bit is large in center load and unloaded volumetric change, drill bit deflecting poor reliability, the broken rock result of rule footpath tooth causes torque-on-bit to increase, deflecting difficulty.
As the exploitation of the important supplement energy shale gas of conventional energy resource, the exploitation difficulty of resource is larger, probing is different from conventional drilling, cluster well in drilling well and horizontal orientation well more, this just needs PDC drill bit to have good directionality and the deflecting easily property controlled, thus shorten the cycle in exploitation early stage, meet the Economic concept of drilling well.
Along with the exhaustive exploitation in a large amount of oil field, oil field individual well output declines gradually.How on the basis of existing well head, to increase single well yield, become the major subjects of numerous expert research.Finding oil field block separately makes hole, not only can increase proprietor's investment, and comparatively havoc can be caused to local environment.Therefore, the basis made hole is carried out secondary development (arriving the oil reservoir verified by beating the deflecting methods such as inclined shaft, horizontal well, cluster well) and meet Economic concept at present and environmental protection requirement.
From the situation of drill bit onsite application, the size of drill bit deflection capacity directly determines the degree that conforms to of the actual deflecting track of well and planned course.Drill bit deflection capacity is strong, the actual path of its inclination section degree that conforms to planned course is high, better can solve the problem such as kick off difficulty, orientation shakiness, greatly can save the time and expense that arrive object oil reservoir, reduce the risk that inclination section downhole tool has an accident simultaneously; On the contrary, drill bit deflection capacity is weak, and the actual path of its inclination section degree that conforms to planned course is low, increases the time that drill bit arrives object oil reservoir, adds wearing and tearing dynamics and the down-hole accident risk of downhole tool simultaneously.
Utility model content
The purpose of this utility model is the shortcoming overcoming prior art, provides a kind of and has good deflection characteristic, and rule position, footpath is not initiatively cut and made bit operation have the PDC drill bit of the directed easily control property of enhancing stably.
The purpose of this utility model is achieved through the following technical solutions: a kind of have the PDC drill bit strengthening directed easily control property, comprise bit body, bizet and cutting teeth, bizet is arranged along bit body bottom surface and side, the gyroscope wheel profile of bizet is provided with multiple cutting teeth, the gyroscope wheel profile of described bizet is by the heart portion connected successively, nose, outside, shoulder and rule footpath section composition, described heart portion is concave spherical surface, be connected with the contour smoothing of nose, the distribution radius R1 of concave spherical surface in drill bit radial direction is greater than 1/4 drill bit radius, be less than 3/4 drill bit radius, the radius of curvature R 2 of concave spherical surface is greater than 1/4 drill bit radius, be less than 5 times of drill bit radiuses, tooth centered by the cutting teeth of bit body center.
Described centre tooth is composite sheet trimming tooth, and trimming length is L, and corner cut is γ: 0 < L≤D, 30 °≤γ≤90 °, and an intersection point of its trimming and cylindrical is on the axis of bit body.
The profile that described shoulder is corresponding is spherical structure, and its radial dimension D corresponds to drill bit design diameter, is connected with the contour smoothing of rule footpath section; The profile of described rule footpath section correspondence is conical structure, and angle≤5 ° of the axis of the conical surface of its correspondence and bit body.
The utility model has the following advantages:
1, drill bit heart portion is concave spherical surface, creeps into in build-up process at directional well, and bottom rock centre forms a sphere, its heart portion and shaft bottom are fitted better, the steering drag in heart portion is less, has good deflection characteristic, enables actual deflecting track and Theoretical Design track quite well.
2, the crown combination of described shoulder, the active that can realize transitional region is cut, and strengthens drill bit attitude drift ability, extends to easement curve rule footpath, now easement curve rule footpath is not initiatively and rock contact, realizes rule position, footpath and does not initiatively cut when directed drilling.
3, the described trimming tooth being positioned at centre, its peak is on the axis of bit body, in drill bit rock break-off process, while guarantee bit central concave spherical surface, trimming tooth rock break-off process can be realized and mainly bear extrusion load, instead of tensile load, thus the broken lithology energy of central cutting tooth can be improved, avoid same cutting teeth to bear stretching extrusion load simultaneously and produce collapsing tooth phenomenon.
4, the hydrophthalmia of heart portion concave spherical surface hat end setting, make cleaner for high-pressure drilling fluid can not only cool cutting teeth and discharge landwaste, lubricate mucous membrane can also be formed between drill bit and heart portion rock, effectively reduce the resistance of drill bit in deflection, thus add the deflection characteristic of this PDC drill bit.
5, the utility model drill bit center load and unloaded volumetric change less, drill bit deflecting reliability can strengthen, the profile design at shoulder and rule footpath place, drill bit deflecting required torque can be made to reduce, and improve borehole wall smoothness, the degrees of offset of directed track can be reduced, thus improve the construction quality of directed drilling.
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model;
Fig. 2 is schematic diagram of the present utility model;
The stereogram of tooth centered by Fig. 3;
Fig. 4 is Fig. 1 central part partial enlargement structural representation;
Fig. 5 is the wide schematic diagram of existing PDC drill bit cloth pinion;
Fig. 6 is that build-up process drill bit breaks rock change in location schematic diagram;
Fig. 7 is existing drill bit build-up process rock wedging amount schematic diagram;
Fig. 8 is drill bit build-up process rock wedging amount schematic diagram of the present utility model;
In figure: 1-bit body, 2-crown profile, 3-heart portion, 4-nose, outside 5-, 6-shoulder, 7-advises footpath section, 8-cutting teeth, 9-centre tooth, 10-hydrophthalmia.
Detailed description of the invention
Below in conjunction with accompanying drawing, the utility model is further described, but protection domain of the present utility model is not limited to the following stated.
As depicted in figs. 1 and 2, a kind of have the PDC drill bit strengthening directed easily control property, comprise bit body 1, bizet 2 and cutting teeth 8, bizet 2 is arranged along bit body 1 bottom surface and side, the gyroscope wheel profile of bizet 2 is provided with multiple cutting teeth 8, the gyroscope wheel profile of described bizet 2 is by the heart portion 3 connected successively, nose 4, outside 5, shoulder 6 and rule footpath section 7 form, described heart portion 3 is concave spherical surface, be connected with the contour smoothing of nose 4, the radius of concave spherical surface in drill bit radial direction is greater than 1/4 drill bit radius, be less than 3/4 drill bit radius, the radius of curvature of concave spherical surface is greater than 1/4 drill bit radius, be less than 5 times of drill bit radiuses, tooth 9 centered by the cutting teeth 8 of bit body 1 center.
As shown in Figure 3 and Figure 4, described centre tooth 9 is composite sheet trimming tooth, and trimming length is L, and corner cut is γ: 0 < L≤D, 30 °≤γ≤90 °, and an intersection point of its trimming and cylindrical is on the axis of bit body 1.
As shown in Figure 2, the profile of described shoulder 6 correspondence is spherical structure, and its radial dimension corresponds to drill bit design diameter, is connected with the contour smoothing of rule footpath section 7; The profile of described rule footpath section 7 correspondence is conical structure, and angle≤5 ° of the axis of the conical surface of its correspondence and bit body 1.
Described both sides, heart portion 3 are also provided with hydrophthalmia 10, the cutting teeth cooling of wing top can not only be given, lubricate mucous membrane can also be formed between drill bit and heart portion rock, effectively reduce the resistance of drill bit in deflection, thus add the deflection characteristic of this PDC drill bit.
In the process of hard formation directed drilling, the heart portion 3 of large radius arc curve is adopted to be that initiatively rock cutting breaks rock, contact rock area is large, controllability increases, drill bit guiding strengthens, increase the cutting teeth quantity of bit shoulder, better distributed load, crown 2 is chip rock initiatively, now advise footpath section 7 chimeric with petrosa, the active realizing transitional region is cut, and enhances drill bit attitude drift ability, now advise footpath section 7 not initiatively and rock contact, realize rule position, footpath and initiatively do not cut when directed drilling.
In the process of soft formation directed drilling, adopt the heart portion 3 of small-radius arc curve, increase the drilling well performance of drill bit.
In the directed drilling process of abrasive layer and hard formation, adopt large radius arc curve and circular curve decentre line heart portion 3 far away, shoulder 6 can be made to become sharp-pointed, thus raising drill bit creeps into performance, now advise footpath section 7 chimeric with petrosa, the active realizing transitional region is cut, and enhances drill bit attitude drift ability, now advise footpath section 7 not initiatively and rock contact, realize rule position, footpath and initiatively do not cut when directed drilling.
In the directed drilling of soft formation, adopt small-radius arc curve and the nearer heart portion 3 of circular curve decentre line, the quantity of bit shoulder 6 place cutting teeth 8 can be increased, the effective situation improved shoulder 6 cutting teeth stress and concentrate, now advise footpath section 7 chimeric with petrosa, the active realizing transitional region is cut, and enhances drill bit attitude drift ability, now advise footpath section 7 not initiatively and rock contact, realize rule position, footpath and initiatively do not cut when directed drilling.
As shown in Figure 2, heart portion 3 is concave spherical surface, the spirogyrate that its structures shape model center place, shaft bottom is milder, thus strengthens deflecting and easily control performance.
As can be seen from figures 6 to 8, PDC drill bit in steering procedure by the A of nose 4
1point moves to A
3point, now the amount axis line of two correspondences meets at O point, compared with existing drill bit, when break-in angle is identical β angle, the OA of drill bit of the present utility model
3value is larger, so the degree that the left side tilts is more weak, the i.e. left side still machinable rock (wedging amount comparatively the right reduces to some extent), the conventional drill then left side likely tilts completely, i.e. not rock cutting, now cutting teeth is hit comparatively large, adds the risk of cutting teeth impact grinding.In build-up process, the utility model drill bit center load and unloaded volumetric change less, drill bit deflecting reliability can strengthen, the profile design at the rule footpath place of drill bit, making drill bit rock break-off process advise footpath tooth is that spherical shape breaks rock, drill bit deflecting required torque can be made to reduce, and improve borehole wall smoothness.
Claims (3)
1. one kind has the PDC drill bit strengthening directed easily control property, comprise bit body (1), bizet (2) and cutting teeth (8), bizet (2) is arranged along bit body (1) bottom surface and side, the gyroscope wheel profile of bizet (2) is provided with multiple cutting teeth (8), it is characterized in that: the gyroscope wheel profile of described bizet (2) is by the heart portion (3) connected successively, nose (4), outside (5), shoulder (6) and rule footpath section (7) composition, described heart portion (3) is concave spherical surface, be connected with the contour smoothing of nose (4), the distribution radius R1 of concave spherical surface in drill bit radial direction is greater than 1/4 drill bit radius, be less than 3/4 drill bit radius, the radius of curvature R 2 of concave spherical surface is greater than 1/4 drill bit radius, be less than 5 times of drill bit radiuses, cutting teeth near bit body (1) center is trimming tooth (9).
2. a kind of PDC drill bit with the directed easily control property of enhancing according to claim 1, it is characterized in that: described trimming tooth (9), trimming length is L, corner cut is γ: 0 < L≤d, 30 ° of < γ≤90 °, and an intersection point of trimming and cylindrical is on the axis of bit body (1).
3. a kind of PDC drill bit with the directed easily control property of enhancing according to claim 1, it is characterized in that: the profile that described shoulder (6) is corresponding is spherical structure, its radial dimension D corresponds to drill bit design diameter, is connected with the contour smoothing of rule footpath section (7); The profile of described rule footpath section (7) correspondence is conical structure, and angle≤5 ° of the axis of the conical surface of its correspondence and bit body (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201521008823.5U CN205135429U (en) | 2015-07-24 | 2015-12-08 | PDC drill bit with reinforcing orientation is nature controlled easily |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2015104407577 | 2015-07-24 | ||
| CN201510440757 | 2015-07-24 | ||
| CN201521008823.5U CN205135429U (en) | 2015-07-24 | 2015-12-08 | PDC drill bit with reinforcing orientation is nature controlled easily |
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| Publication Number | Publication Date |
|---|---|
| CN205135429U true CN205135429U (en) | 2016-04-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510895382.3A Pending CN105464599A (en) | 2015-07-24 | 2015-12-08 | PDC drill bit with directional easy controllability enhancing performance |
| CN201521008823.5U Active CN205135429U (en) | 2015-07-24 | 2015-12-08 | PDC drill bit with reinforcing orientation is nature controlled easily |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201510895382.3A Pending CN105464599A (en) | 2015-07-24 | 2015-12-08 | PDC drill bit with directional easy controllability enhancing performance |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105464599A (en) * | 2015-07-24 | 2016-04-06 | 四川深远石油钻井工具股份有限公司 | PDC drill bit with directional easy controllability enhancing performance |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113279699A (en) * | 2021-04-14 | 2021-08-20 | 西南石油大学 | PDC drill bit tooth arrangement design method |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201013242Y (en) * | 2007-03-15 | 2008-01-30 | 中国石化集团胜利石油管理局钻井工艺研究院 | Directional drilling bit |
| CN201159050Y (en) * | 2007-12-14 | 2008-12-03 | 青岛石大华通科技有限公司 | Blade type PDC drill bit for petroleum and natural gas drilling |
| CN201786265U (en) * | 2010-03-26 | 2011-04-06 | 成都百施特金刚石钻头有限公司 | Polycrystalline diamond compact (PDC) drill head with stable tool face for directional driller |
| CN201738815U (en) * | 2010-05-10 | 2011-02-09 | 中国石油天然气股份有限公司 | Inclining-prevention PDC drill bit |
| GB2503145B (en) * | 2011-02-10 | 2019-05-15 | Smith International | Kerfing hybrid drill bit and other downhole cutting tools |
| CN104619946A (en) * | 2012-08-17 | 2015-05-13 | 史密斯国际有限公司 | Downhole cutting tools having hybrid cutting structures |
| CN104196458A (en) * | 2014-08-26 | 2014-12-10 | 莱州市原野科技有限公司 | Sharp-tooth PDC drill bit |
| CN105464599A (en) * | 2015-07-24 | 2016-04-06 | 四川深远石油钻井工具股份有限公司 | PDC drill bit with directional easy controllability enhancing performance |
-
2015
- 2015-12-08 CN CN201510895382.3A patent/CN105464599A/en active Pending
- 2015-12-08 CN CN201521008823.5U patent/CN205135429U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105464599A (en) * | 2015-07-24 | 2016-04-06 | 四川深远石油钻井工具股份有限公司 | PDC drill bit with directional easy controllability enhancing performance |
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| Publication number | Publication date |
|---|---|
| CN105464599A (en) | 2016-04-06 |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |