CN103343667A - Steel PDC drilling bit with erosion-proof tooth cavities - Google Patents
Steel PDC drilling bit with erosion-proof tooth cavities Download PDFInfo
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- CN103343667A CN103343667A CN2013102972643A CN201310297264A CN103343667A CN 103343667 A CN103343667 A CN 103343667A CN 2013102972643 A CN2013102972643 A CN 2013102972643A CN 201310297264 A CN201310297264 A CN 201310297264A CN 103343667 A CN103343667 A CN 103343667A
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Abstract
The invention relates to a steel PDC drilling bit with erosion-proof tooth cavities which is used in the field of petroleum and geological drilling. The steel PDC drilling bit with the erosion-proof teeth comprises a drilling bit body and a knife wing, wearing layers are welded on the front face and the back face of the knife wing, the tooth cavities are formed in the upper portion of the front face of the knife wing, and clad sheet cutting teeth are arranged in the tooth cavities. The steel PDC drilling bit with the erosion-proof tooth cavities is characterized in that cavity grooves are formed in the front ends of the tooth cavities along the edges of the tooth cavities, and wearing layers are welded on the cavity grooves. According to the steel PDC drilling bit with the erosion-proof tooth cavities, the erosion-proof capacity of the front portions of the tooth cavities is enhanced, and thus the service life of the steel PDC drilling bit is prolonged. Further, more welding material is coated on certain parts around the tooth cavities, the thickness of the wearing layers is decreased gradually, the wearing layers around the tooth cavities are distributed reasonably, less welding material is used, and the machining cost of the drilling bit is decreased on the premise that the erosion-proof capacity of the tooth cavities is enhanced. Further, due to the fact that slopes which incline inwards are arranged on the back of the nose part and the shoulder parts of the knife wing, the interference between the back side of rock debris and a well bottom face behind the knife wing is reduced effectively, the drilling resistance of the drilling bit is decreased, the rock breaking efficiency of the drilling bit is improved, and the mechanical drilling speed of the drilling bit is increased.
Description
Technical field
The present invention relates to the anti-erosion steel body PDC drill bit in a kind of tooth cave for oil and geological drilling field, belong to petroleum geology drilling tool technical field.
Technical background
Steel body PDC drill bit when long-time the use or shaft bottom mud sand content when heavier, near near the tooth cave of the position nozzle easily by erosion.The appearance of this situation mainly is that the suffered wall shear stress in erosion position is bigger, and should place's protective capacities relative deficiency.Existing position, steel body PDC bit cutting tooth tooth cave to cover weldering thickness be 1.5 ~ 2mm, often be prone to because the drill bit initial failure problem that the bit teeth cave is caused by erosion.The scene, oil field is to use the life-span to grow to the requirement of steel body PDC drill bit, can repeatedly repair.Therefore, must guarantee that drill bit erosion do not occur when long-time the use, to prolong the application life of drill bit.But existing steel body PDC drill bit erosion control arbor still difficulty satisfies above-mentioned instructions for use.
On the other hand, the wing back of existing PDC drill bit is that the outer surface of wing is flat face, and the angle that also is wing back and wing front is 90 ° or is slightly less than 90 °.When drill bit creeps at a high speed, because drill bit is that spiral moves downward, behind the broken rock of cutting teeth, the landwaste amount that the nose of drill bit wing and shoulder produce is more, has certain delay in the tooth back, thereby form the talus deposit of wing back, talus deposit not only can limit the degree of depth on the wedging stratum of bit cutting tooth, wearing and tearing drill bit wing back, and can increase the resistance that creeps into of drill bit, thereby limited the further raising of drill bit rate of penetration, reduced drilling life of bit.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of tooth cave to prevent erosion steel body PDC drill bit at the deficiency that above-mentioned prior art exists.
The present invention is that the technical scheme that the problem of the above-mentioned proposition of solution adopts is: comprise bit body and wing, the weldering wearing layer is applied in the front and back of wing, the top, front of wing offers the tooth cave, be installed on the composite sheet cutting teeth in the tooth cave, it is characterized in that offering the cave groove at edge, front end edge tooth cave, tooth cave, apply the weldering wearing layer in the groove of cave.
Press such scheme, described tooth cave is semi arch hole or more than half circular hole, and the described cave groove of offering along edge, tooth cave is that radius of curvature is greater than the half-arc groove of tooth cave arc radius or more than half arc groove.
Press such scheme, described cave fluted shaft is 2 ~ 6mm to the degree of depth, and described cave groove radial depth is 2 ~ 6mm.
Press such scheme, the wearing layer thickness that weldering is applied in described wing front is 1 ~ 2 mm, cover weldering thickness from top to bottom gradient successively decrease.
Press such scheme, the wearing layer bending that weldering is applied in described wing back extends to the wing back side, and thickness is 1 ~ 2 mm, successively decreases from front to back.
Press such scheme, the footpath deposited weldering in section inclined-plane wearing layer is being protected for protecting directly section in the shoulder top of described wing.
Press such scheme, described guarantor footpath offers pit or groove on the section inclined-plane, applies the weldering wearing layer in pit or groove.
Press such scheme, it is intilted domatic in the back of the nose of wing and/or shoulder to be that outer surface arranges.
Press such scheme, described intilted domatic section start extands rearward to the wing back side apart from bottom, composite sheet cutting teeth tooth cave 2 ~ 6mm from section start.
Press such scheme, the vertical distance of described intilted domatic lowest part and section start is more than or equal to 4mm.
Press such scheme, described intilted domatic two is connected with the straight back of wing remainder mutually by transition is domatic.
Press such scheme, described wearing layer is tungsten carbide of nickel-base wearing layer or iron-based carbine abrasion-proof layer.
Beneficial effect of the present invention is: 1, strengthened the anti-impact erosion ability of front portion, tooth cave, thereby prolonged the application life of steel body PDC drill bit; 2, by the local increase of scolder and the thickness-tapered of wearing layer of applying around the tooth cave, can cover the many relatively surface consolidation materials of weldering around in the tooth cave, make the wearing layer around the tooth cave obtain more reasonably distributing, under the prerequisite of strengthening the anti-erosion performance in tooth cave, can reduce integral body and cover the consumption of wlding material, reduce the drill bit processing cost; 3, protecting the wear-resisting deposited layer of the deposited weldering in section inclined-plane, footpath, strengthened PDC bit gauge protection inclined-plane abrasive resistance, frequently lacked in the operation for a long time in directional drilling, can effectively reduce the wearing and tearing of protecting section inclined-plane, footpath, thereby avoid directional well steel body PDC drill bit to cause drill bit to lose efficacy because protecting the inefficacy in advance of footpath section, therefore the drilling footage of single directional well steel body PDC drill bit has improved 10% ~ 25%, thereby prolongs drilling life of bit; And protect a section inclined-plane, footpath offer pit and groove can make wear-resisting deposited layer with protect a footpath section inclined-plane interlock get more firm, the section inclined-plane, guarantor footpath of more effective protection steel body PDC drill bit; 4, by arranging intilted domatic at the more wing nose of landwaste amount and the back of shoulder, not only strengthened the drill bit nose, the cleaning of shoulder cutting teeth and cooling, the landwaste that will creep into generation is drained fast, and can effectively reduce landwaste and between wing back and shaft bottom face, produce interference, reduce the resistance that creeps into of drill bit, improved the efficiency of breaking rock of drill bit, thereby improve the rate of penetration of drill bit, prolong the application life of drill bit, wing back to the few inner cone of landwaste amount and other parts keeps flat face constant, guarantee the contact area in inner cone and other parts and shaft bottom, thereby guaranteed the stability that drill bit creeps into.
Description of drawings
Fig. 1 is the partial sectional view of the tooth cave part of one embodiment of the invention.
Fig. 2 is the distribution schematic diagram that the weldering wearing layer is applied in the wing part front of one embodiment of the invention.
Fig. 3 is the three-dimensional structure diagram of one embodiment of the invention.
Fig. 4 is the three-dimensional structure diagram of second embodiment of the invention.
Fig. 5 is the partial view of protecting footpath section chamfered portion in the second embodiment of the invention.
Fig. 6 is the partial view of protecting the another kind of structure of footpath section chamfered portion in the second embodiment of the invention.
Fig. 7 is the three-dimensional structure diagram of third embodiment of the invention.
Fig. 8 is the plan structure figure of Fig. 7.
Fig. 9 is the A-A sectional view among Fig. 8.
The specific embodiment
The present invention is further illustrated below in conjunction with accompanying drawing.
First embodiment as shown in Figure 1, 2, 3, comprising bit body 10 and be installed in bit body periphery and end face at interval to the bending shape wing 4 of outer process, is chip area between the wing, is provided with nozzle 5 in the chip area, the tooth cave is offered in the top, front of wing, described tooth cave is more than half circular hole, offers the cave groove at edge, front end edge tooth cave, tooth cave, and the radius of curvature of cave groove is greater than tooth cave arc radius, be more than half arc groove, the cave fluted shaft is 3mm to the degree of depth, and radial depth is 4mm, applies weldering wearing layer 6 in the groove of cave.Described tooth cave is spaced along wing front outline and installs, and is distributed in interior tapering, nose, the shoulder of wing and protects the footpath section, is installed on columned composite sheet cutting teeth 1 in the tooth cave; The weldering wearing layer is all applied in front and back at wing, wearing layer 2 thickness of the deposited weldering in described wing front from top to bottom gradient successively decrease, wherein the first half front region 7 wearing layer thickness in nearly tooth cave are thicker is 2 ~ 1.5mm, and the wearing layer thickness-tapered of the latter half front region 8 is 1.5 ~ 1mm; The wearing layer of the wearing layer of wing front and cave groove applies and is welded into one.The wearing layer bending that weldering is applied in described wing back extends to the wing back side, and thickness successively decreases from front to back, progressively is decremented to 1mm by 2 mm thickness.In the drill bit process, at first tooth cave structure is processed, adopt graphite to be bonded at the tooth acupuncture point for sheet in the position of composite sheet correspondence and put, apply weldering with applying the weldering high-abrasive material by Fig. 1, deposited welding structure shown in Figure 2 then.Wherein the deposited weldering wearing layer thickness of cave groove peripheral region is the thickest, and near the deposited weldering wearing layer thickness of peripheral region, tooth cave secondly, the deposited weldering wearing layer thickness that leaves peripheral region, tooth cave is the thinnest, and the material that weldering is applied on the surface is tungsten carbide of nickel-base.
Drill bit and other downhole tool couple together, together at the bottom of the lower going-into-well, and turn on pump circulating fluid and the rotary drilling of pressurizeing then.Around the tooth cave, namely near the suffered drilling fluid impact force maximum in deposited welding zone territory around the tooth cave, also be to be easy to generate the position that erosion was lost efficacy most, it is the thickest that weldering thickness is covered at this place, thereby anti-impact erosion ability is more strong, and the impact force gradient that produces at all the other deposited welding zone territory drilling fluids reduces, and it covers also corresponding gradient attenuate of weldering thickness.Thereby reached the anti-impact erosion ability that has strengthened front portion, tooth cave, thereby prolonged the application life of corresponding drill bit.Simultaneously, change owing to apply the layer thickness gradient, reduced the use of surface consolidation material, reduced the processing cost of drill bit.
Second embodiment is shown in Fig. 4,5,6, above the shoulder of wing, be guarantor footpath section, protect the upper end of footpath section for protecting section inclined-plane 9, footpath, be the most of weldering wear-resistant material layer that applies in section inclined-plane, described guarantor footpath with the difference of a last embodiment, wear-resistant material layer applies layer for the iron-based tungsten carbide, applies the wear-resistant material layer of weldering and flushes with the section inclined-plane, guarantor footpath that does not apply weldering.Can offer flat pit on a section inclined-plane, guarantor footpath, flat pit, applies in the flat pit and welds wear-resistant material layer along offering along chamfered edge.Or offer vertical straight trough at interval protecting a section inclined-plane, upper edge, inclined-plane, footpath, vertically apply the weldering wear-resistant material layer in the straight trough.The high-abrasive material layer height is concordant with face that the inclined-plane stays.
The 3rd embodiment such as Fig. 7,8, shown in 9, the tooth cave is offered in the front of wing, be installed on the composite sheet cutting teeth 1 of cylinder bulk in the tooth cave, the composite sheet cutting teeth is spaced along the wing outline and installs, be distributed in the interior tapering 11 of wing, nose 12 and shoulder 13 etc., difference is in the back of the nose of wing and shoulder to be that nose and the shoulder of outer surface of wing arranges intilted domatic, the spacing a of described intilted domatic section start and bottom, composite sheet cutting teeth tooth cave is 2.3mm, domaticly extand rearward to the wing back side 14 from section start, domatic lowest part (with the intersection at the back side) is 24.5mm with the vertical distance b of section start.Described intilted domatic two is connected mutually by the domatic back with the wing remainder of transition, and the back of wing remainder is flat face.
In drilling process, when cutting teeth wedging stratum, landwaste that its wimble fraction in wing produces is detained in the wing back, but because its landwaste amount is less relatively and cutting teeth have suitable high grinningly, so it does not exert an influence to the rate of penetration of PDC drill bit; More relatively at the landwaste that wing nose, shoulder produce, but the wing back is the domatic structure of introversion, this domatic structure can effectively be migrated landwaste to chip area, thereby prevented the interference that landwaste moves downward drill bit, reduced wearing and tearing and the frictional resistance of landwaste to drill bit wing back face, and then improved the rate of penetration of drill bit, prolonged drilling life of bit.
Claims (10)
1. the anti-erosion steel body PDC drill bit in tooth cave comprises bit body and wing, and the weldering wearing layer is applied in the front and back of wing, the top, front of wing offers the tooth cave, be installed on the composite sheet cutting teeth in the tooth cave, it is characterized in that offering the cave groove at edge, front end edge tooth cave, tooth cave, apply the weldering wearing layer in the groove of cave.
2. the anti-erosion steel body PDC drill bit in tooth according to claim 1 cave, it is characterized in that described tooth cave is semi arch hole or more than half circular hole, the described cave groove of offering along edge, tooth cave is that radius of curvature is greater than the half-arc groove of tooth cave arc radius or more than half arc groove.
3. the anti-erosion steel body PDC drill bit in tooth cave according to claim 1 and 2 is characterized in that described cave fluted shaft is 2 ~ 6mm to the degree of depth; Described cave groove radial depth is 2 ~ 6mm.
4. the anti-erosion steel body PDC drill bit in tooth according to claim 1 and 2 cave is characterized in that it is 1 ~ 2 mm that the wearing layer thickness of weldering is applied in described wing front, cover weldering thickness from top to bottom gradient successively decrease.
5. the anti-erosion steel body PDC drill bit in tooth cave according to claim 1 and 2 is characterized in that the wearing layer bending of the deposited weldering in described wing back extends to the wing back side, and thickness is 1 ~ 2 mm, successively decreases from front to back.
6. the anti-erosion steel body PDC drill bit in tooth according to claim 1 and 2 cave, the shoulder top that it is characterized in that described wing be for protecting the footpath section, applies the weldering wearing layer protecting section inclined-plane, footpath.
7. the anti-erosion steel body PDC drill bit in tooth cave according to claim 6 is characterized in that offering pit or groove on the section inclined-plane, described guarantor footpath, applies the weldering wearing layer in pit or groove.
8. the anti-erosion steel body PDC drill bit in tooth according to claim 1 and 2 cave, it is intilted domatic to it is characterized in that in the back of the nose of wing and/or shoulder being that outer surface arranges.
9. the anti-erosion steel body PDC drill bit in tooth cave according to claim 8 is characterized in that described intilted domatic section start apart from bottom, composite sheet cutting teeth tooth cave 2 ~ 6mm, extands rearward to the wing back side from section start.
10. the anti-erosion steel body PDC drill bit in tooth cave according to claim 8 is characterized in that the vertical distance of described intilted domatic lowest part and section start is more than or equal to 4mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310297264.3A CN103343667B (en) | 2013-07-16 | 2013-07-16 | A kind of tooth cave fluid erosion prevention steel body PDC drill bit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310297264.3A CN103343667B (en) | 2013-07-16 | 2013-07-16 | A kind of tooth cave fluid erosion prevention steel body PDC drill bit |
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| Publication Number | Publication Date |
|---|---|
| CN103343667A true CN103343667A (en) | 2013-10-09 |
| CN103343667B CN103343667B (en) | 2015-10-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310297264.3A Active CN103343667B (en) | 2013-07-16 | 2013-07-16 | A kind of tooth cave fluid erosion prevention steel body PDC drill bit |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104358522A (en) * | 2014-11-06 | 2015-02-18 | 中国石油化工股份有限公司 | PDC (Polycrystalline Diamond Compact) drill bit suitable for shale gas well shale stratum drilling |
| CN113279701A (en) * | 2021-07-23 | 2021-08-20 | 四川川庆石油钻采科技有限公司 | Wear-resistant erosion-resistant PDC drill bit and design method thereof |
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| CN202140024U (en) * | 2011-06-29 | 2012-02-08 | 武汉亿斯达工具有限公司 | Novel steel body type PDC drill bit |
| CN203362043U (en) * | 2013-07-16 | 2013-12-25 | 江汉石油钻头股份有限公司 | Steel body polycrystalline diamond compact (PDC) bit with anti-erosion teeth holes |
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Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US4792001A (en) * | 1986-03-27 | 1988-12-20 | Shell Oil Company | Rotary drill bit |
| US7997359B2 (en) * | 2005-09-09 | 2011-08-16 | Baker Hughes Incorporated | Abrasive wear-resistant hardfacing materials, drill bits and drilling tools including abrasive wear-resistant hardfacing materials |
| US20080053709A1 (en) * | 2006-08-29 | 2008-03-06 | Smith International, Inc. | Diamond bit steel body cutter pocket protection |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104358522A (en) * | 2014-11-06 | 2015-02-18 | 中国石油化工股份有限公司 | PDC (Polycrystalline Diamond Compact) drill bit suitable for shale gas well shale stratum drilling |
| CN113279701A (en) * | 2021-07-23 | 2021-08-20 | 四川川庆石油钻采科技有限公司 | Wear-resistant erosion-resistant PDC drill bit and design method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103343667B (en) | 2015-10-14 |
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Address after: 430223 Hubei city of Wuhan province science and Technology Park East Lake New Technology Development Zone, Road No. five Patentee after: SINOPEC OILFIELD EQUIPMENT CORPORATION Address before: 430223 Hubei city of Wuhan province science and Technology Park East Lake New Technology Development Zone, Road No. five Patentee before: Jianghan Petroleum Drilling Bit Co., Ltd. |
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Effective date of registration: 20180223 Address after: 430223, No. 5, Chinese workers' garden, Temple Hill community, East Lake New Technology Development Zone, Wuhan, Hubei Co-patentee after: SINOPEC OILFIELD EQUIPMENT CORPORATION Patentee after: Kingdream Sinopec Petroleum Machinery Co. Ltd. Address before: 430223 Hubei city of Wuhan province science and Technology Park East Lake New Technology Development Zone, Road No. five Patentee before: SINOPEC OILFIELD EQUIPMENT CORPORATION |
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