CN106437525B - A kind of composite drill bit suitable for bad ground - Google Patents

Abstract

The invention discloses a kind of composite drill bits suitable for bad ground, including drill body, the wing of opposite drill body consolidation, the gear wheel of opposite drill body rotation connection, and it is arranged in hydrophthalmia or nozzle on drill body, several first group of cutting tooth is provided on wing, recess is arranged to fix first group of cutting tooth in the wing cloth flank of tooth, gear wheel is rotatablely connected by bit leg and drill body, tooth is installed on gear wheel, the body profiles line of the body profiles line of at least one wing and at least another wing has at least one not overlapping region collectively covering in range, and at least one coincidence point or overlapping region.This structure feature can make drill bit work with asynchronous cutting way, it not only can increase longitudinal abrasion length of drill bit, extend bit life, and drill bit can be made to creep into state all in high specific pressure in entire drilling process, the ability for enhancing drill bit intrusion rock, so that drill bit be made all to be improved in the drilling speed of bad ground and service life.

Description

A kind of composite drill bit suitable for bad ground

Technical field

The invention belongs to oil-gas drilling engineering, mine engineering, building foundation engineering constructions, geological drilling, tunnel The technical equipment such as engineering, the hydrology, shield and no-dig technique field, more particularly to a kind of Drilling bore bit.

Background technique

Drill bit is to fractured rock, the rock crushing tool of formation pit shaft in drilling engineering, and there are commonly PDC drill bits and gear wheel Drill bit.PDC drill bit by high rigidity, it is wear-resisting, can carry out shearing-crushing rock from sharp composite polycrystal-diamond, PDC drill bit by In rate of penetration is high in soft-medium hard formation, the service life is long, drilling cost is low, is used widely in drilling engineering.It is existing Usually all there are several wings by the fixed cutter drill bits of representative of PDC drill bit, be arranged radially along drill bit on wing There is multiple cutting elements (to PDC drill bit, cutting element is mainly composite polycrystal-diamond, abbreviation composite sheet or PDC tooth).But When boring chance hard formation, the cutting tooth on the nose and shoulder of PDC drill bit is difficult effective wedging stratum, thus greatly reduces machine Tool drilling speed.Rock bit broken rock in a manner of impacting crushing forms deeper crushing teeth hole in shaft bottom.When stratum is harder, no Rock can be made to generate volume broken rock, to reduce the utilization rate of energy, efficiency of breaking rock is lower.

It is succeeded in developing from shell Hughes Electronics, U.S. gear wheel-PDC composite drill bit technology in 2009, research is single both at home and abroad Position starts to study composite drill bit with manufacturing enterprise, and develops patented product with independent intellectual property rights.Shell Hughes Company has submitted more parts of patent applications to the U.S. and World Intellectual Property Organization in succession in recent years, wherein United States Patent (USP) In " Hybrid bit with variable exposure " (patent No.: US 8336646B2), for gear wheel cutting unit The cutting profile of cutting profile and fixed cutting unit has carried out several matched designs.

But include above-mentioned patented technology in the prior art, wing where fixed cutting tooth is cut according to synchronizing Principle is cut to be designed, i.e., on each wing the cutting tooth of different radial positions simultaneously or it is synchronous (or substantially simultaneously, it is substantially same Step) enter working condition, start to cut bottom rock, and start simultaneously at and wear.Green bit (bores under ideal working condition The stabilization drilling state that is overlapped with wellbore center of head center) drilling rock when, simultaneously participate in scrape cut rock all cutting tooths it is equal For main cutting tooth, main cutting tooth is the primary cutting element of drill bit fractured rock, the front side of each wing is typically provided at, with benefit In reaching better cooling and cleaning effect.Other than cutting tooth, standby cutting tooth can be also set on drill bit as needed (i.e. when main cutting odontotripsis to a certain extent after the cutting tooth just devoted oneself to work, such as rear toothrow) and assisted machining structure it is (main Refer to the structure for helping main cutting tooth broken rock, such as bores tooth, or the buffer structure of protection cutting tooth effect, such as buffering section or buffering tooth Deng).

In drill bit design process, it will usually arbitrarily determine a plane by drill bit central axis as cloth tooth shaft face (being also referred to simply as axial plane), the radial and axial position of each cutting tooth can accurately be expressed on the axial plane on drill bit.When When drill bit rotates under conditions of axial position is constant around own axes, the land contour line and axial plane of cutting tooth are crossed to form friendship Line, the intersection are the axial plane contour line of cutting tooth, then by main cutting teeth all on drill bit (or on several specified wings or dise knife All main cutting teeth) axial plane contour line collect in the axial plane, be formed axial plane cloth tooth figure (or several specified knives of drill bit The axial plane cloth tooth figure of the wing or dise knife).Because axial plane cloth tooth figure can accurately reflect on drill bit cutting tooth to the covering feelings of bottom rock Condition, therefore it is called shaft bottom drape tooth figure, abbreviation drape tooth figure or shaft bottom coverage diagram.

In the shaft bottom coverage diagram of drill bit, make an external envelope song tangent with the axial plane contour line of all main cutting teeth Line, as the cutting contour line (namely crown profile line of drill bit) of drill bit, as shown in Fig. 2, for the brill of routine PDC in the prior art The shaft bottom coverage diagram of head, wherein the horizontal direction labeled as R is that drill bit is radial, and the vertical direction labeled as Z is that drill bit is axial, The curve of label 11 is the cutting contour line of drill bit in the prior art.

In the shaft bottom coverage diagram of drill bit, if only specifying the cutting tooth on wing or dise knife to show some, and incite somebody to action Cutting tooth on other wings or dise knife conceals, and is formed the axial plane cloth tooth figure of the wing or dise knife.In wing or dise knife In axial plane cloth tooth figure, make an external envelope curve tangent with the axial plane contour line of each main cutting tooth, which is then referred to as The cutting contour line of the wing or dise knife.The cutting contour line of wing is reflected when main cutting tooth is distributed (energy close enough on wing The shaft bottom radial zone where the wing is completely covered) when, the basic or desired profile in the shaft bottom which independently cuts Shape feature.

If drill bit rotates under conditions of axial position is constant around own axes, for a certain wing body, front side The intersection of face and its cloth flank of tooth will form one using drill bit central axis as the surface of revolution of axis as the rotation of drill bit is scanned, The intersection of the surface of revolution and axial plane is the body profiles line of wing, as shown in Fig. 2 or 12, wherein the curve marked as 32, The as body profiles line of wing.Similarly, the body profiles line of dise knife is also such.Under normal conditions, due to being arranged in knife The proud exposure of main cutting tooth on the wing cloth flank of tooth is same or similar (closing on except the region of gage land), so wing The shape for cutting contour line and its body profiles line is in parastate substantially, and it is obvious poor only to have in the region for closing on rule diameter It is different.Therefore, based on the needs for realizing synchronous cutting principle, the body profiles line of each wing of drill bit is mutual weight in the prior art It closes or essentially coincides.In other words, theoretically the body profiles line of each wing of drill bit is with drill bit central axis same On the surface of revolution of axis, thus they are all one sections in an identical curve or same curve.This feature can be referred to as For the consistency or synteny of each wing body profiles line of drill bit.Obviously, this consistency or synteny are not only present in each knife The body profiles line of the wing, and be also to set up to the cutting contour line of each wing.Exactly this structure feature, so that being fixedly arranged at Main cutting tooth on each wing of drill bit simultaneously or synchronous cutting bottom rock, and then can form pit shaft.

Utility model patent " with second level toothing polycrystalline diamond compact bit " (Patent No.: ) and the utility model patent " composite polycrystal-diamond with the longitudinal standby cutting structure of stand alone type ZL200620033337.3 In drill bit " (Patent No.: ZL200720082270.7), a kind of PDC drill bit with standby (second level) toothing is disclosed, Its common feature is in the bit body that standby tooth is consolidated under main cutting tooth, i.e., standby tooth is relative to the inside cloth of bit body It sets, is upwardly formed multiple step structure to indulge in drill bit.The purpose that longitudinal standby tooth is arranged in two patents is to increase drill bit The longitudinal direction of Adamas cutting tooth can wear length, extend drilling life of bit.But longitudinal standby tooth in above-mentioned two scheme is It is interior inserted, and its main cutting tooth press synchronous cutting principle work, as it is inserted in assisted machining structure must be in main cutting tooth Abrasion totally and ontology have part wears after just start to work, but inside inserted rock cutting while, wing ontology with The contact of stratum occurrence of large-area, reduces standby cutting tooth and acts on the ratio pressure of rock, significantly so that the drilling of drill bit be made to imitate Rate is very limited.

The existing PDC drill bit with synchronous cutting principle in face of complicated bad ground (high rigidity, high abrasive or even Containing the heterogeneities such as gravel layer, interlayer stratum) when, not only drilling efficiency is restricted, and service life is also undesirable.It is main former Because being: first, can have the ability of stronger wedging or intrusion rock surface to guarantee drill bit in hard formation drilling, just Need using size (diameter) lesser cutting tooth, however the proud exposure of minor diameter cutting tooth is small, can wear height it is significantly low In major diameter cutting tooth, but at this time, the rate of wear of cutting tooth faster, therefore is formed the design of bad ground drill bit In insoluble contradiction: according to major diameter cutting tooth, cutting tooth, which is difficult to invade rock, (especially to be occurred to wear to a certain degree After), drill bit efficiency of breaking rock is low；According to minor diameter cutting tooth, the working life of cutting tooth is again inadequate.Second, drill bit is hard Cutting tooth is frequently subjected to stronger shock loading when creeping into stratum, heterogeneity stratum, and a small amount of or even individual cutting tooths easily occur Fall off, be broken, fragmentation, diamond layer the rapid failures phenomenon such as burst apart, this phenomenon will cause close region once occurring Cutting tooth then generates ring cutting phenomenon, i.e., drill bit is in the radial zone because of chain failure caused by increased workload The exposure part of cutting tooth is wholly or largely ground off, and grinds annular groove on each wing ontology of drill bit in turn.Ring cutting is existing As once occurring, the ontology of each wing directly forms face contact with rock on drill bit, even if the cutting tooth on wing is not yet complete Portion has been ground, but due to reduction more serious than pressure, so the efficiency of breaking rock of drill bit can be remarkably decreased.So when grinding annular groove on drill bit Afterwards, drill bit is generally considered as to have lost or close to cutting power is lost, cannot not only reenter well use, reparation is even connected when serious (cutting tooth that replacement or renovation have worn away) is all difficult to carry out.

Summary of the invention

It is an object of the invention to: it proposes a kind of composite drill bit suitable for bad ground, drill bit can be obviously improved multiple Working performance under the formation conditions such as miscellaneous application conditions, bad ground, especially high rigidity, high abrasive, high inhomogeneity.

The object of the invention is realized by following technical proposals:

A kind of composite drill bit suitable for bad ground, including drill body, the wing of opposite drill body consolidation, relatively The gear wheel of drill body rotation connection, and the hydrophthalmia or nozzle that are arranged on drill body, be provided on wing several the One group of cutting tooth, the wing cloth flank of tooth are arranged recess and are rotated to fix first group of cutting tooth, gear wheel by bit leg and drill body It connects, tooth is installed on gear wheel, the body profiles line of at least one wing and the body profiles of at least another wing Line collectively cover in range have at least one not overlapping region (or for different wide region) and at least one coincidence point or Overlapping region (or for wide region).

For drill body according to the present invention, bit leg, gear wheel, wing, the wing cloth flank of tooth, hydrophthalmia, nozzle, wing sheet Body contour line or even first group of cutting tooth, be concept well known in the art, this will not be repeated here, can with reference to as Fig. 1,11, It is the structural schematic diagram of drill bit of the present invention shown in 15 and Figure 22, wherein 1 be drill body, 2 be gear wheel, 21 be bit leg, 8 be Tooth, 3 be wing, 33 be the wing cloth flank of tooth, 41 be first group of cutting tooth, 61 be hydrophthalmia or nozzle；It as shown in figure 11, is this hair (Figure 12 is each wing body profiles line of Fig. 1 drill bit shape and position in coverage diagram to each wing body profiles line schematic diagram in bright Set), wherein 32 be wing body profiles line.

In existing technology, on drill bit the body profiles line of all wings same using drill bit central axis as axis On the surface of revolution of line, thus they belong to an identical curve, or are respectively one section in same curve.But in the present invention In, each wing can have wing body profiles line that is independent, being not affiliated with same surface of revolution, and at least one wing Body profiles line and the body profiles line of at least another wing there is not overlapping region simultaneously collectively covering in range (hereinafter referred to as different wide region) and coincidence point or overlapping region (hereafter referred to collectively as with wide region, comprising coincidence point and are overlapped area Domain).

It is worth noting that the coverage area (namely radial cutting working range or region of wing) of wing refers to wing Radial extension between upper most inner side cutting tooth and outermost cutting tooth.It can also be between wing contour line Origin And Destination Coverage area of the radial extension as wing.Described herein collectively covers range, refers to two or more wing phases The radial working region of (being collectively responsible for) of overlapping, collectively covers range a and Fig. 7 such as Fig. 7 (a) four-headed arrow meaning region (b) four-headed arrow meaning region shown in collectively covers range b, and wherein Fig. 7 (a) show a long wing on same drill bit The body profiles line schematic diagram of (the operator wing) and a short sword wing (secondary wing), Fig. 7 (b) show two rimmer knifes on same drill bit The body profiles line schematic diagram of the wing (the operator wing), it is clear that it is different that wing represented by Fig. 7 (a) and Fig. 7 (b), which collectively covers range, 's.Further, each wing body profiles line, which collectively covers the coincidence point in range at it, can be the intersection point of each curve, can also To be the point of contact between curve, the intersection point as shown in dash area 34 in Fig. 7 (a) and point of contact；Each wing body profiles line is at it Collectively covering the overlapping region in range is the part that each wing body profiles line is overlapped or essentially coincides, such as Fig. 7 (a), Fig. 7 (b) overlapping region shown in dash area 34 in；On the other hand, collectively covering in range, on wing body profiles line except The part of coincidence point and overlapping region (also known as with wide region) is that the not overlapping region of wing body profiles line is (also known as different Wide region).In addition to coincidence point, the width of overlapping region and overlapping region is not defined as its width shared by the drill bit radial direction.

First group of cutting tooth on wing is arranged generally along the body profiles line of wing, and forms corresponding wing cutting Contour line.By the above, in existing bit technique, it is same that each wing cutting contour line is overlapped in the coverage diagram of shaft bottom Curve, meanwhile, this curve is also the cutting contour line of entire drill bit, and parallel with the body profiles line of wing or substantially flat Row.And each wing body profiles line in the present invention with several not overlapping regions will self-assembling formation have and several be not overlapped area The wing in domain cuts contour line, as shown in figure 3, C is overlapping region in the drill bit coverage diagram being made of two wings, N is not heavy Close region.On the other hand, according to previously described definition content, bit cutting contour line is actually each wing cutting profile Line takes the lead in being superimposed with stratum contact area in same axial plane, and such as Fig. 3,14,23, label 11 is bit cutting profile Line, label 31 are that wing cuts contour line.It integrates, if the ontology wheel of the body profiles line of some wing and other wings Profile is collectively covering in range while having several different wide regions and several same wide regions, then the cutting profile of the wing Line is not overlapped (referred to as asynchronous cutting zone, hereinafter referred to as asynchronous area) in partial region with bit cutting contour line, and another A part of region (including a point or one section of curve) coincide or essentially coincide (referred to as synchronous cutting region, hereinafter referred to as together Walk region).Obviously, the different wide region of wing body profiles line corresponds to the asynchronous area of wing cutting contour line, with exterior feature region It is then corresponding with retaining zone.

In working principle, with asynchronous area wing compared to conventional synchronous cutting wing the difference is that: knife On the wing and not all tooth simultaneously participates in work, but only part cutting tooth (cutting tooth of retaining zone) participates in work, waits this After a little cutting tooth abrasions to a certain extent, the cutting tooth of other regions (cutting tooth of asynchronous area) just can touch rock simultaneously Start rock cutting work.Obviously, it is (simple that the wing with this cutting tooth work characteristics stage by stage is referred to as asynchronous cutting wing Claim asynchronous wing), when the bit pressure undertaken is identical, compared to the prior art (cutting tooth of different radial positions on wing Simultaneously or rock is cut in synchronous participation), the ratio pressure for acting on rock is high.Asynchronous wing number is more, this effect promoted than pressure It is more significant with (referred to as pressurization effectiveness), if drill bit whole wing is all using the wing with asynchronous cutting characteristic, pressurization effect With more protruding, it is advantageous to be promoted drill bit in the ability of bad ground intrusion rock.For conventional bit, wing is cut It cuts profile and overlaps or essentially coincide with bit cutting profile, the cutting tooth of different radial positions is simultaneously or synchronous on wing Participation rock cutting be referred to as synchronous cutting.Drill bit comprising asynchronous wing is known as asynchronous cut drill (referred to as asynchronous brill Head).

If there was only a single point or single very narrow region and drill bit on drill bit on the cutting contour line of certain asynchronous wing Cutting contour line is coincided or is essentially coincided, then means the cutting contour line of the wing where this point or very narrow region Position on be evagination, and the cutting contour line of wing other positions is then with respect to bit cutting contour line indent, it is clear that only It is to work from the beginning in the cutting tooth of boss, with the continuous abrasion of this or these tooth, is in indent on wing The cutting tooth at position just gradually starts contact and rock cutting.Equally, if had on the cutting contour line of certain asynchronous wing several A point or several mutually intermittent regional areas coincide with bit cutting contour line, then the cutting contour line of the wing is at these Position is local evagination, and remaining region is then with respect to bit cutting contour line indent, therefore at the beginning of the drilling process of drill bit, only There is the cutting tooth at these evagination positions in rock cutting, then cutting tooth is worn up to the cutting tooth at remaining indent position in male part position The process of rock cutting is just progressed into after to a certain degree, to realize the work stage by stage of different parts cutting tooth on same wing Make.Obviously, asynchronous wing is substantially exactly the wing with part cutting feature, this when the bit pressure that wing undertakes is identical The ratio pressure that wing acts on rock in local cutting zone obvious exceeds conventional wing.Asynchronous wing number is more, this promotion It is more significant than the effectiveness of pressure (referred to as pressurization effectiveness).If drill bit whole wing all uses asynchronous wing, drill bit can claim at this time It for disparate step drill bit, is pressurized effectiveness and more protrudes, be advantageous to be promoted drill bit in the ability of bad ground intrusion rock.

It is corresponding to foregoing teachings, the regional area of initial cuts is participated on asynchronous wing, cutting contour line is evagination, The wing body profiles line naturally also evagination of corresponding position, as shown in Figure 8.Further, have on wing body profiles line multiple When local crowning, make wing body profiles that the shape feature of rising and falling shape be presented, as shown in Fig. 9,12,18,19.To two sheets For the different asynchronous wing of body chamfered shape, the local crowning on wing is more, then collectively covers within region at it, two Intersection or crosspoint between wing body profiles line is more.If the local crowning position of asynchronous wings multiple on drill bit is handed over Mistake distribution can complete the covering to the even whole radial zones of bottom section using mutually overlapping multiple local crownings.In In drilling process, as long as the convex portion on drill bit is not smoothed, pressurized effect to some extent there is.In addition, part The height of protrusion can be higher than the diameter (knuckle-tooth) or working depth (non-knuckle-tooth) of cutting tooth significantly, and height difference is bigger, not only knife The pressurization shear action timeliness of the wing is longer, and the length of another aspect wing body profiles line is also longer, on naturally same wing Cloth tooth region it is bigger, cutting tooth quantity is also more, the number of teeth increase is mutually matched with the feature that cutting tooth works stage by stage, To extend the working life of asynchronous drill bit on the basis of increasing wing drilling than pressing.

In the present invention, the cutter set density of drill bit can be effectively adjusted by wing body profiles line, improve drill bit adaptively The range of layer and lasting drilling ability.It can be worn by the axial direction that the echelon cloth tooth that the present invention program is formed can effectively increase drill bit Volume extends the service life of drill bit.In broken rock, gear wheel cutting structure can carry out bottom rock composite drill bit of the present invention Effectively precrushing forms discrete broken hole one by one in shaft bottom, and the cutting element (cutting tooth) of diamond fraction your energy Effective wedging stratum, and earth formation material is removed with lesser energy, completion is crushed bottom rock.Two kinds of different broken rock machines Organically blending for the cutting structure of reason, enhances efficiency of breaking rock.In conjunction with the design feature of the asynchronous cutting of wing in the application, In While improving efficiency of breaking rock, extend the service life of drill bit.

Therefore, according to above to the object of the invention and rationale, it is possible to understand that and confirmation, the present invention are defined " the body profiles line of wing and the body profiles line of other wings there is at least one not to be overlapped area collectively covering in range Domain (or for different wide region) " should not do absolute understanding, i.e., should not be certain to be not intended to that may be present in the prior art Under knowing or under accidental or for the body profiles line and other knives with caused wing under the other purposes of wide of the mark of the present invention The body profiles line of the wing there are it is lesser degree of be not overlapped cover including；Those skilled in the art be based on aforementioned the object of the invention and Rationale obviously can be correct for the degree of " the not overlapping region " according to the prior art of grasp, common knowledge Understand, without especially being defined；Typically, it of the invention " promote drill bit in order to preferably realize and is invaded in bad ground The ability of rock " purpose, this does not account for and entirely collectively covers the ratio of range areas and be preferably not less than 25% in overlapping region.

Preferably, being at least whole or the curve of major part evagination there are two the body profiles line of wing, and described Each curve concave portion vertex is not identical along the radial position of drill bit radial direction.

In the present solution, the outer substantial only a fraction of convex domain of wing body profiles line correspond to wing cutting contour line with The region (retaining zone) that bit cutting contour line coincides；And remaining region on wing body profiles line is cut corresponding to wing Cut the region (asynchronous area) that contour line is not overlapped with bit cutting contour line.The radial position on the vertex of two wing concave portions It sets not identical, wing cutting contour line can just be made to coincide in vertex corresponding position and bit cutting contour line in design, The cutting tooth of two wing vertex and adjacent locations just becomes the initial cutting tooth for participating in work at this time, and cutting far from the region Cutwork wouldn't be participated in by cutting tooth (except retaining zone).In this way, the ratio pressure acted in initialization cutting tooth is higher than routine Drill bit is conducive to the ability for improving drill bit intrusion rock.In the present solution, body profiles line is the song of whole or most of evagination Line is actually unimodal curve, i.e., there is only a protrusions on wing body profiles line, as shown in Figure 4.Shown in Fig. 4 (a) Wing body profiles line is the curve of whole evagination, and wing body profiles line shown in Fig. 4 (b) is the song of most of evagination Line, the curve of label 32c are the body profiles line of conventional wing in the prior art, are marked in phantom herein, to highlight The feature of heretofore described entirety or most of evagination wing body profiles line.Although wing body profiles are unimodal song Line, if the local crowning of each wing body profiles curve is radially mutually staggered along drill bit, these wings still can have asynchronous Region.

Preferably, be at least the curve at least one local crowning there are two the body profiles line of wing, and Respectively there is at least one local crowning partly or entirely mutually wrong along drill bit radial direction or along bit cutting contour line between the curve It opens.

It is different from whole or most of wing body profiles line of evagination only single in aforementioned schemes, the knife in this programme Wing body profiles line has multiple local crownings, and therefore, the distribution of each local crowning can have different situations, as shown in Figure 6. Wherein, Fig. 6 (a) show each local crowning along drill bit radial distribution, and on different wing body profiles lines local crowning along boring Head radial (direction arrow A in figure) is partly or entirely staggered；Fig. 6 (b) show each local crowning along bit cutting contour line point Cloth, and local crowning is partly or entirely wrong along bit cutting contour line (direction arrow B in figure) on different wing body profiles lines It opens.It is worth noting that local crowning distribution represented in Fig. 6 (a) and Fig. 6 (b) and displaced manner be only two kinds more Typical distribution mode, but it is not limited to the two ways.

In above scheme, wing body profiles line is the curve with one or more local crownings, can in design So that wing cutting contour line coincides in the vertex corresponding position of local crowning with bit cutting contour line, each wing office at this time The vertex of portion's protrusion and the cutting tooth of adjacent locations just become the initial cutting tooth for participating in work, and the cutting tooth far from the region (except retaining zone) wouldn't participate in cutwork.Such structure makes drill bit in drilling process, on synchronization wing only There is the part cutting tooth contact shaft bottom at the top of local crowning, reduces the contact area of drill bit and rock, the ratio in cutting tooth Pressure is higher than conventional bit, enables the effective wedging stratum of drill bit；Even if drill bit is worn, part cutting tooth is caused to be destroyed, Remaining part cutting tooth following contacts shaft bottom not being worn is still suffered from, cutwork is put into, guarantees that drill bit creeps into overall process All it is high specific pressure, is conducive to the raising of drill bit rate of penetration.

Secondly, the wing body profiles line to rise and fall joins the cutting tooth on same wing body profiles line stage by stage With broken rock, also make its cloth tine length longer, with regard to more, the number of teeth increases and cutting tooth point the cloth number of teeth amount on naturally same wing The feature of stage work is mutually matched, thus increasing working life of the wing drilling than extending drill bit on the basis of pressure. Local crowning especially on the body profiles line of wing mutually staggers, and has preferable cloth tooth effect, it can forms part The alternate covering (it can be appreciated that being longitudinally formed multiple step structure, the center portion region of such as Figure 14 and Figure 23) of protrusion, Be obviously prolonged cutting tooth wears length.And the cutting tooth in alternate covering region remains as the table edge being exposed to outside wing Tooth can keep high specific pressure when drilling.In addition, in the present solution, also allowing the local crowning on each curve in the radial position of drill bit Set coincidence.Polycrystalline diamond compact bit (200620033337.3) with second level toothing and after there is free-standing longitudinal direction The polycrystalline diamond compact bit (200720082270.7) of standby cutting structure, discloses a kind of standby (second level) toothing PDC drill bit, common feature is in the bit body that standby tooth is embedded under main tooth (base tooth), i.e. standby tooth is relative to brill Head body is inwardly arranged, is upwardly formed multiple step structure to indulge in drill bit, but longitudinal standby tooth in above-mentioned two scheme is It is interior inserted, it is that first group of cutting odontotripsis on initial contact stratum is totally just started to work after rear and ontology has part wears, While standby tooth rock cutting, wing ontology is contacted with stratum occurrence of large-area, reduces standby cutting significantly Tooth acts on the ratio pressure of rock, so that the drilling efficiency of drill bit be made to be very limited.

Meanwhile having the presence of several local crownings on wing, the chip space of drill bit is increased, landwaste is reduced and is cutting Accumulation near tooth is conducive to the heat dissipation and cooling of cutting tooth, reduces the thermal wear of cutting tooth, improve drill bit from another point of view Working performance.

Preferably, the body profiles line of the wing of at least 40% quantity is the song at least one local crowning Line, and respectively there is at least one local crowning to mutually stagger between the curve along drill bit radial component or all.

In above scheme, if the wing quantity of different exterior feature is maintained at certain proportion range, can better and more scientifically it play different The asynchronous shear action of wide wing.Obviously, in this scenario 40% ratio may result in a non-integer as a result, this When, according to the understanding of common sense, need to carry out rounding: for example, a total of 6 wings of drill bit, then 40% is exactly 2.4, rounding 2 A wing.

Preferably, be at least the curve at least one local crowning there are two the body profiles line of wing, and The not overlapping region width of the curve at least accounts for a quarter of drill bit radius.

In above scheme, if asynchronous area range is maintained at certain proportion, the asynchronous cutting of drill bit can be preferably played Effect.The length for increasing asynchronous area can allow the service life of cutting tooth in drill bit each region to be mutually matched, and reach reduction drilling The purpose of cost.

Preferably, be at least the curve at least one local crowning there are two the body profiles line of wing, and The local crowning mutually staggered between the curve is distributed in the radial zone other than drill bit one third radius.

PDC drill bit crown is generally located in the radial zone other than drill bit one third radius, crown (also referred to as nose) and And crown is very fast with the cutter-wear rate of exterior domain (external taper and shoulder).On the one hand, the cutting tooth position in crown region More sensitive to the variation (such as soft or hard alternately stratum) of formation lithology in the least significant end of drill bit, drill bit is passing through soft or hard alternating Interface when, be easy to cause the overload of crown region cutting tooth and collapse the failure phenomenons such as damage.On the other hand, crown is with outskirt The cutting tooth in domain movement velocity during rock cutting is higher, and when hard formation and heterogeneity stratum are crept into, cutting tooth is impacted Load is relatively large, and frictional heat generation is also than more serious, so the speed of its wear-out failure is apparently higher than cutting close to centre Cut tooth.Using the above scheme, asynchronous area can cover the fireballing region of cutting tooth failure on drill bit, to significantly improve drill bit These positions can wear height, increase cutting structure intrusion rock ability, promoted bit life, reduce drilling cost.

Preferably, be at least the curve at least one local crowning there are two the body profiles line of wing, and The local crowning mutually staggered between the curve is distributed in the radial zone within 2/3rds radius of drill bit.

Under certain special operation conditions, during combined drilling, drill bit movement complicated condition, not there is only oscillation crosswise, And there are shimmy, and drill bit is likely to be at the working condition not parallel with hole axis.For composite drill bit of the present invention Speech, in perimeter by the co-operation region of dise knife and fixing wing, and center portion region is relatively weak, in this condition Under, the cutting tooth in drill bit internal region is easy that Fast Wearing occurs because of unbalance loading.Due to PDC drill bit the interior zone number of teeth compared with It is few, so, once individual tooth failures, it is easy to chain reaction occurs, leads to the generation of internal ring cutting failure phenomenon, this failure Phenomenon is commonly called as phenomenon " from the bottom of one's heart ".In the program, asynchronous area is arranged in the region within 2/3rds radius of drill bit, Neng Gouxian Write improve drill bit these positions can wear height, to extend PDC drill bit under the Special complexes operating condition such as combined drilling Service life, reduce and even avoid the generation of phenomenon from the bottom of one's heart.

Preferably, the local crowning shape of wing body profiles line is similar or identical, it can also be dissimilar or not identical. Preferably, the local crowning shape of the wing body profiles line of at least 50% quantity is similar or identical.Obviously, in this scenario 50% ratio may result in a non-integer as a result, at this time, it may be necessary to carrying out rounding.For example, a total of 5 wings of drill bit Body profiles line, then 50% is exactly 2.5, rounding is 2 wing body profiles lines.

Preferably, the shape of local crowning can be to be similar parabola shaped, trapezoidal, round, ellipse etc. can also For the combination between them, as shown in Figure 9.

Preferably, the height of all wing body profiles line local crownings is not less than 8mm.

Preferably, the height of the whole or most of evagination of all wing body profiles lines is not less than 8mm.

In above scheme, boundary's point of elevated regions is set forth as follows first: for the region of whole evagination, raised boundary Point should be respectively wing body profiles line close to the endpoint and wing body profiles line bizet of drill bit center portion and gage areas Separation puts 322 as shown in Figure 10 (a)；For the region of most of evagination or local crowning, if entire protrusion occupy same Between two troughs of one smoothed curve, then the two troughs must have a common tangent and respectively two point of contacts, this two A point of contact is its raised boundary point, and 322 are put as shown in Figure 10 (b)；If entire protrusion both ends are the non-light of different curved sections Slip point, then this tie point is the boundary's point for being used as the protrusion, and 322 are put as shown in Figure 10 (c)；If the side of some protrusion For the continuously smooth curve with trough, the other side is previously described curved section Non-smooth surface tie point, then the tie point is first As one of its boundary's point, another boundary's point be from this to raised other side smoothed curve section trough at made tangent line point of contact, 322 are put as shown in Figure 10 (d).Accordingly, the width of certain protrusion (including whole evagination, most of evagination and local crowning) It is defined as the length of the protrusion two sides circle point line, W as shown in Figure 10, height is then defined as the point on fillet curve extremely The maximum distance of two sides circle point line, H as shown in Figure 10, obtaining the point of the maximum distance on fillet curve is the protrusion Vertex.It should be noted that since the shape of protrusion can have many situations of change, although above-mentioned definition is just for having Several convex shapes of limit are made, but its essence spirit is equally applicable to different shape protrusion (including whole evagination, major part Evagination and local crowning) other situations.Raised region involved in this patent full text (including whole evagination, major part are outer Convex and local crowning) calculating according to said method, be not repeated.

Preferably, being at least the curve at least one local crowning, institute there are two the body profiles line of wing It states between curve not overlapping region and is distributed in drill bit radial direction one third with exterior domain, and the height of local crowning is from bit central It becomes larger outward.

In the program, the height of local crowning becomes larger outward from bit central, and drill bit is better adapted to The bad grounds such as high abrasive stratum, gravel layer, and under the high speed conditions such as combined drilling, extended using asynchronous cutting principle The working life of these region cutting tooths.

Preferably, different exterior feature wing is greater than other regions in the local crowning height of drill bit crown region or nasal region.

When drill bit passes through the heterogeneities formation condition such as interlayer, gravel layer, nose, the shoulder of drill bit often carry a large amount of broken Rock load, power consumption, so that the cutting tooth Fast Wearing at these positions, and then make drill bit premature failure.In the program, by increasing The local crowning of drill bit crown region or nasal region not only improves drill bit in the rock wedging ability at these positions, also increases It has been added to wear length, to extend bit life on the basis of promoting drilling efficiency.

Preferably, being at least the curve at least one local crowning, institute there are two the body profiles line of wing It states at least one local crowning between each curve to overlap or essentially coincide, and is arranged between different wing body profiles lines It is mutually staggered in first group of cutting tooth of the local crowning that coincides.

Preferably, at least one wing has preposition wing body profiles line and at least one postposition wing sheet simultaneously Body contour line, preposition wing body profiles line and postposition wing body profiles line are the song at least one local crowning Line.It is preferred that local crowning is radial along drill bit or partly or entirely mutually staggers along bit cutting contour line.

Above scheme is substantially to merge the cutting structure of two asynchronous wings on a wing body.In the program, Two different wing body profiles lines are provided at least two rows of cutting tooths on same wing, therefore wing number can not be increased Under conditions of amount, increase the cutter set density of drill bit, strengthen the asynchronous cutting structure of drill bit, while being also conducive to expand the stream of drill bit Road more sufficiently, effectively utilizes bit operation space, improves the comprehensive performance of drill bit.

Preferably, at least one wing has preposition wing body profiles line and at least one postposition wing sheet simultaneously Body contour line, preposition wing body profiles line and postposition wing body profiles line are the song at least one local crowning Line, at least one local crowning is overlapped or is essentially coincided on each curve, and between different wing body profiles lines First group of cutting tooth for being arranged in the local crowning that coincides mutually staggers.It can make the asynchronous cutting knot of privileged sites on drill bit in this way Structure is strengthened.

Preferably, second group of cutting tooth that at least one proud exposure is less than or equal to zero is provided on the wing, Or at least one empty slot or/and second group of cutting tooth being fixed in empty slot.

Second group of cutting tooth and sky in the program, relative to its proud exposure of wing body profiles line less than or equal to zero Slot (including built-in tooth and built-in table are inserted etc.) be simutaneously arranged in a mixed way in wing body, wing can not only be greatly increased Length is worn, wing body space is also effectively utilized, while ensuring to creep into than pressure, further extends bit life.

Preferably, cloth in whole on wing body profiles line or major part evagination or the corresponding wing region of local crowning It is equipped with second group cutting tooth of at least one proud exposure less than or equal to zero or at least one empty slot or/and is fixed on sky Second group of cutting tooth in slot.

In the program, since the local crowning drilling of wing body is higher than pressing, cutting tooth arranges negligible amounts, therefore relatively general Logical wing is easier to wear, and after the abrasion of this part wing body, region setting empty slot can be such that worn-out cutting tooth carries in outside Wing body is detached under lotus rapidly, and then exposes empty slot and second group of cutting tooth, worn-out region is repaired, is being guaranteed On the basis of drilling life of bit, the ability of bit cutting rock updated.

Preferably, corresponding to the wing cutting contour line and bit cutting contour line of wing body profiles line local crowning It is tangent.

Preferably, corresponding to the wing cutting contour line and bit cutting contour line of wing body profiles line local crowning It partially overlaps.

Preferably, be equipped on gear wheel width it is inserted (i.e. 4 points of addendum widths of tooth be more than or equal to its tooth post width, tool Body concept is shown in Chinese patent " a kind of width insert bit ", the patent No. 2013100636239), and the value of tooth top angle of deflection Range is 70 °~90 °.

In above scheme, angle of deflection refers to addendum line (i.e. along cutting tooth addendum width direction and vertically with cutting axis) The angle of the wheel cone nut line of gear wheel where with cutting tooth, as shown in figure 16.The setting of large deflection angle, so that gear wheel is the same as phase on gear ring Adjacent interdental space interval substantially reduces, and greatly strengthens the stability in gear wheel tooth alternating rock break-off process, while still Remain the advantage of the inserted technology of gear wheel.In this way, width is inserted in rock break-off process, each tooth bottoms out time relative increase, and It is significantly reduced with rock impact effect is acted on close to the linear load with static pressure, enhances the stability of bit operation.

It is preferred that the gear wheel is disc cutter, cutting tooth is in continuous dise knife shape on disc cutter.

Preferably, the cutting tooth is composite polycrystal-diamond, polycrystal diamond composite teeth, thermostabilization plycrystalline diamond Buddha's warrior attendant Stone cutting tooth, natural diamond cutting tooth, impregnated Adamas cutting tooth, carbide cutting tooth, cubic boron nitride cutting tooth, pottery Porcelain cutting tooth or cutting tooth comprising diamond or cubic boron nitride.

The foregoing main solution of the present invention and further alternatives thereof can be freely combined to form multiple schemes, be this Invention can be used and claimed scheme；And it is of the invention, between (each non conflicting selection) selection and between other selections It can also be freely combined.Those skilled in the art, which can be illustrated after understanding the present invention program according to the prior art and common knowledge, to be had Multiple combinations are the claimed technical solution of the present invention, do not do exhaustion herein.

Explanation of nouns:

The proud exposure of cutting tooth: refer to the distance on the highest point to wing body profiles line of cutting land.Exposure is high Degree can be just, be it is negative, can also be equal to zero, when cut land be exposed to except wing ontology when, the proud exposure of tooth is positive Value.

First group of cutting tooth: it is arranged in the cutting tooth that proud exposure on the wing body cloth flank of tooth is greater than zero.

Second group of cutting tooth: being arranged on wing, and is less than or equal to zero relative to wing body profiles line proud exposure Cutting tooth.Interior inserted and built-in table is inserted etc. to belong to second group of cutting tooth.

It is interior inserted: to be less than or equal to zero cutting tooth relative to wing body profiles line proud exposure, cutting tooth is in addition to cutting Other surfaces (mainly side and bottom end face) and the comprehensive engagement of wing body other than working face, and closed by this contact System realizes the consolidation of cutting tooth.I.e. cutting tooth is embedded in completely in wing body or bit body, as shown in fig. 20b.

Empty slot: being set on the wing body below first group of cutting, can be through slot, can also be non-through blind slot. The effect of empty slot first is that can play reduce bit wear after the invalid bit pressure unfavorable to rock cutting that is undertaken of wing ontology, Second is that providing cloth tooth space for built-in table is inserted.

Built-in table is inserted: being fixed in the empty slot being arranged on wing body, and its land exposure empty slot surface where it Cutting tooth.After first group of cutting tooth and completely worn out wing ontology in built-in table inserted front, built-in table is inserted can be as One group of cutting tooth rock cutting like that in a manner of the inserted high specific pressure of table, obtains the stock-removing efficiency of drill bit a degree of extensive It is multiple.Built-in table it is inserted unlike it is interior it is inserted be completely embedded in wing body, as illustrated in fig. 20.The design of empty slot is so that apply It is not absorbed by surrounding wing body in the inserted bit pressure of built-in table, that is, the inserted ratio pressure of built-in table is not because of neighbouring wing body In the presence of and be substantially reduced so that its operating condition and first group of cutting tooth are consistent or close, that is, in empty slot near cutting tooth Wing body is not involved in contact rock, thus when making the inserted work of built-in table in the form of table edge rock cutting, thus its drilling is than pressure It is not substantially reduced for opposite first group of cutting tooth, while guaranteeing cutting tooth wedging ability, that improves drill bit uses the longevity Life.

Cloth tooth shaft face or axial plane: by the plane of drill bit central axis, it is mainly used for expressing the diameter of each cutting tooth on drill bit To and axial position and cutting tooth to the coverage condition of bottom rock and the elementary contour feature in shaft bottom.

Shaft bottom coverage diagram: when drill bit rotates under conditions of axial position is constant around own axes, the land of cutting tooth Contour line and axial plane are crossed to form intersection, which is the axial plane contour line of cutting tooth, then by the axial plane wheel of all main cutting teeth Profile collects in the axial plane, is formed the axial plane cloth tooth figure of drill bit.It is cut on drill bit because axial plane cloth tooth figure can accurately reflect Tooth is cut to the coverage condition of bottom rock, therefore is called shaft bottom drape tooth figure, abbreviation drape tooth figure or shaft bottom coverage diagram.

Bit cutting contour line: in the coverage diagram of shaft bottom, one, work is tangent with the axial plane contour line of all main cutting teeth External envelope curve, as bit cutting contour line.The curve characterizes the elementary contour feature in the drilled out shaft bottom of drill bit.

Wing cuts contour line: in the shaft bottom coverage diagram of drill bit, only specifying the cutting tooth on wing to represent some Come, and the cutting tooth on other wings is concealed, is formed the axial plane cloth tooth figure of the wing.In the axial plane cloth tooth figure of wing In, make an external envelope curve tangent with the axial plane contour line of each main cutting tooth, which is the cutting wheel of the wing Profile.

Wing body profiles line: it is defining in cloth tooth shaft face, if drill bit is under conditions of axial position is constant around itself axis Line rotation, then for a certain wing body, the intersection of leading flank and its cloth flank of tooth will scan to form one with the rotation of drill bit The intersection of a space curved surface, the space curved surface and axial plane is the body profiles line of wing.

Preposition, postposition wing body profiles line: if by two or more respectively adjacent with wing body profiles line Wing merges into same wing, then just will appear a plurality of wing body profiles line, in this case, edge on the wing body after merging Bit direction forefront is known as preposition wing body profiles line, remaining is postposition wing contour line.Same wing body On adjacent blades body profiles line between may also set up the necessary structure such as runner, hydrophthalmia and nozzle.

Compared with prior art, the beneficial effects of the present invention are:

(1) in composite drill bit of the present invention the body profiles line of fixing wing it is not identical, can effectively adjust the cloth of drill bit Tooth density, the range on raising drill bit adaptation stratum and lasting drilling ability.

(2) present invention forms multiple step structure along the cutting tooth of wing body profiles line arrangement in the coverage diagram of shaft bottom, The axial wear volume that drill bit can be increased, extends the service life of drill bit.It is ground in first order cutting tooth (main cutting tooth) After damage, and being exposed to outer secondary cutting tooth can quickly participate in cutting, and keep the high specific pressure state of drilling.

(3) the wing cutting contour line of drill bit and bit cutting contour line are not exactly the same in technical solution of the present invention, and It is to partially overlap or contact, other regions do not contact.This wing with asynchronous cutting feature in the present invention, what is undertaken When bit pressure is identical, compared to the wing with synchronous cutting feature, the ratio pressure for acting on rock is obvious high.Asynchronous wing number is got over More, this promotion is more significant than the effectiveness of pressure (referred to as pressurization effectiveness).

(4) when wing body profiles line is alternately formed by connecting by lug boss and recessed portion.Wing has lug boss and recessed portion Presence, increase the chip space of drill bit, reduce accumulation of the landwaste near cutting tooth, be conducive to the scattered hot and cold of cutting tooth But, the thermal wear of cutting tooth is reduced.

(5) present invention reduces drill bit to the sensibility of formation condition, widens single drill bit to the adaptation range on stratum (from soft Stratum is to hard formation), in soft formation, the cutting tooth near protrusion can regard a big cutting element as and cut stratum to scrape, Obtain higher rate of penetration and drilling efficiency.In hard formation, by whole high specific pressure and axial multilayer can wear volume, obtain Obtain higher rate of penetration and service life.

(6) the technology of the present invention can reinforce the region of composite drill bit local weak, so that composite drill bit is held Continuous drilling ability is further enhanced.

Detailed description of the invention

Fig. 1 is the drill bit structure schematic diagram of first embodiment of the invention；

Fig. 2 is the cloth tooth coverage diagram of existing drill bit；

Fig. 3 schematic illustration of overlapping region for overlapping region in the present invention and not；

Fig. 4 is the structural schematic diagram of body profiles line entirety evagination or most of evagination；

Fig. 5 is that the body profiles line of wing is the unimodal curve of whole evagination and the vertex of the convex portion of different wings exists The structural schematic diagram mutually staggered in same drill bit axial plane；

Fig. 6 is the schematic diagram that protrusion is radially staggered with bit cutting contour line direction；

Fig. 7 is that wing body profiles line collectively covers region, coincidence point, overlapping region and not overlapping region in the present invention Schematic diagram.

Fig. 8 is the structural schematic diagram of body profiles line local crowning；

Fig. 9 is that body profiles line has multiple local crownings and the different structural schematic diagram of convex shape；

Figure 10 is the definition schematic diagram of protrusions circle point of the present invention and ledge width, height of projection；

Figure 11 is the top view of Fig. 1；

Figure 12 is shape of the wing body profiles line of Fig. 1 in coverage diagram；

Figure 13 is the cloth tooth figure of each wing of Fig. 1；

Figure 14 is the overall coverage diagram of Fig. 1；

Figure 15 is the structural schematic diagram of second embodiment of the invention；

Figure 16 is the structural schematic diagram of the inserted deflection angle of width of Figure 15；

Figure 17 is the structural schematic diagram of third embodiment of the invention；

Figure 18 is structural schematic diagram inserted in fourth embodiment of the invention；

Figure 19 is the inserted structural schematic diagram of table built in fourth embodiment of the invention；

Figure 20 be respectively the built-in inserted and interior inserted cross-sectional view of table

Figure 21 is the difference schematic diagram that table built in difference is inserted in the present invention；

The structural schematic diagram and shaft bottom coverage diagram of the respectively fifth embodiment of the invention of Figure 22,23；

Figure 24 is the cloth tooth figure of each wing of sixth embodiment of the invention；

In figure: 1, drill body；11, bit cutting contour line；2, gear wheel；21, bit leg；3, wing；31, wing cutting wheel Profile；32, the body profiles line of wing；321, the convex portion of wing body profiles line；322, raised boundary point；323, protrusion top Point；33, the wing cloth flank of tooth；41, first group of cutting tooth；42a, built-in table are inserted；It is 42b, interior inserted；5, empty slot；61, hydrophthalmia or spray Mouth；8, tooth.

Specific embodiment

Following non-limiting examples are for illustrating the present invention.

Embodiment one

As shown in Fig. 1,11,12,13,14, a kind of long-life drill bit with asynchronous cutting principle, including drill body 1, The wing 3 that opposite drill body 1 consolidates, the gear wheel 2 that opposite drill body 1 is rotatablely connected, and be arranged on drill body 1 Hydrophthalmia or nozzle 61 have bit leg 21 on drill body 1, and gear wheel 2 is mounted on bit leg 21, are formed and are rotatablely connected with bit leg 21, tooth It is installed on tooth 8 on wheel 2, several first group of cutting tooth 41 is provided on wing 3, setting recess is used on the 3 cloth flank of tooth 33 of wing To fix first group of cutting tooth 41, hydrophthalmia or nozzle 61, the sheet of at least one wing 3 are provided in the runner between wing Body contour line 32 (may include preposition wing body profiles line and postposition wing body profiles line) and at least another wing 3 Body profiles line 32 collectively covering in range have at least one not overlapping region and at least one coincidence point or coincidence Region.First group of cutting tooth 41 can be composite polycrystal-diamond, polycrystal diamond composite teeth, thermostabilization plycrystalline diamond Buddha's warrior attendant Stone cutting tooth, natural diamond cutting tooth, impregnated Adamas cutting tooth, carbide cutting tooth, cubic boron nitride cutting tooth, pottery Porcelain cutting tooth or cutting tooth comprising diamond or cubic boron nitride.

The body profiles line of wing 3 can be the unimodal curve of an only entirety or most of evagination, as shown in figure 4, It is also possible to the polymodal curve with multiple local crownings as shown in Figure 5, wherein by taking Fig. 2,4 as an example, labeled as the level of R Direction is that drill bit is radial, and the vertical direction labeled as Z is that drill bit is axial, drill bit coverage diagram, wing body profiles line in this patent Signified drill bit radially, axially should all so understand in the schematic diagram that figure etc. indicates in drill bit axial plane, repeat no more.With drill bit Drilling direction be axis of ordinates, radial is axis of abscissas.Whole or most of evagination refers on single wing body profiles line Whole section or most of (the ratio between concave portion width and drill bit radius are greater than 1/2) be a curve in spirogyrate, the curve It is formed by connecting by one or more convex outer curve sections and one or more straightways.The body profiles curve one of existing PDC drill bit As be that another the different arc section or straightway being smoothly connected by an arc section and therewith constitute the (dotted line in such as Fig. 4 It is shown), the top area of evagination is referred to as " crown " region or the nasal region of drill bit.Commonly used by existing PDC drill bit originally Body contour curve mainly includes following several types (disregarding the small chamfering with bit gauge diameter joint): bicone: straight line is (interior Cone)+circular arc (nose)+straight line (outer shoulder)；Single circular arc type: straight line (inner cone)+circular arc (nose and outer shoulder)；Bicircular arcs type: Straight line (inner cone)+circular arc (nose)+circular arc (outer shoulder).This few class contour curve belongs to the feelings of whole or most of evagination Condition is more specifically the unimodal curve of whole evagination.As shown in Fig. 4 (a), Fig. 4 (b), wherein knife shown in Fig. 4 (a) Wing body profiles line is the curve of whole evagination, and wing body profiles line shown in Fig. 4 (b) is the curve of most of evagination, The curve of label 32c is the body profiles line of conventional wing in the prior art, is marked in phantom herein, to highlight this hair The feature of entirety or most of evagination wing body profiles line described in bright.Fig. 7, several situations shown in Fig. 8 are that drill bit is each The different reference example of radial position on the vertex of the whole or most of concave portion of wing body profiles line.

Local crowning in the present invention refers to that (convex portion is wide for regional area on single wing body profiles line for setting The ratio between degree and drill bit radius are less than or equal to convex portion 321 1/2), each convex portion is known as a local crowning.It constitutes The curve of local crowning can be smooth curve, be also possible to Non-smooth surface curve.It is several as shown in Fig. 9 (a), (b), (c) Situation, wherein the curve of label 32c is the body profiles line of conventional wing in the prior art, is marked in phantom, so as to convex Show the feature of the heretofore described wing body profiles line with multiple local crownings.As an example, the ontology of wing 3 can To be the unimodal curve of an only entirety or most of evagination, as shown in Fig. 3,4,5, and convex apexes 323 are mutually staggered, such as Fig. 3, shown in 5.When wing ontology is made of multiple local crownings, the shape of local crowning can be continuous class parabola such as Fig. 9 (a), the convex hull shape curve for being also possible to multistage curve and circular arc composition can also be rectangle, such as Fig. 9 such as Fig. 9 (b) (c), the cross sectional shape of this outer lug can also be trapezoidal, oval, the protrusion of the broken line shapes such as diamond shape, square, Yi Jiqi The curve form of his shape only lists wherein more typical portion-form herein.

As an example, when wing 3, which is, has the polymodal curve of multiple local crownings 321, the curve of local crowning can be with It is smooth curve, is also possible to Non-smooth surface curve.In coverage diagram, each wing 3 is radially mutually staggered in drill bit, such as Figure 12 institute Show.Figure 14 be Fig. 1 shaft bottom coverage diagram, Figure 13 be each wing 3 coverage diagram, Cong Tuzhong it can easily be seen that each wing 3 ontology Contour line 32 is mutually indepedent, and the cutting contour line 32 of each wing 3 and the cutting contour line 11 of drill bit are only in partial region or point It is overlapped, each wing 3 all has asynchronous cutting function.And overlapped coverage (multiple step knot is formd in the coverage diagram of shaft bottom Structure), especially in local crowning 321, the cutting tooth being exposed to outside wing body 3 is mutually overlapping.When take the lead in contacting with stratum cuts After cutting odontotripsis, the cutting tooth being exposed in outer secondary cutting structure will participate in cutting quickly, and drill bit drilling overall process is all High specific pressure is conducive to the raising of drill bit rate of penetration.In the present solution, also allowing the lug boss on each wing body profiles line curve Divide and is overlapped in the radial position of drill bit.

Gear wheel 2 is rotatably connected on bit leg 21, and the tooth 8 when drilling on gear wheel 2 is in a manner of impacting crushing, in shaft bottom shape At broken hole discrete one by one, formed to stratum with it is broken.And the Adamas cutting tooth on wing 3 is set with less Energy removes the rock by tooth precrushing.Meanwhile the wing with asynchronous cutting power, it is able to maintain the high ratio of whole process of drilling Pressure guarantees in composite drill bit while extending the service life of drill bit, improves efficiency of breaking rock.

As the further improvement of the embodiment above, same wing 3 is provided simultaneously with wing body profiles line and extremely A few postposition wing contour line, and be fixed with along wing body profiles line and wing additional wheel profile and at least two ranked first in total Group cutting tooth 41.

Embodiment two

As shown in figure 15, the present embodiment is basically the same as the first embodiment, the difference is that: the cutting tooth 8 on gear wheel 2 is Width is inserted, as shown in figure 16.In the present embodiment, gear wheel 2 is crushed in a manner of approximate static pressure, cleaves working method broken rock, thereon Gear ring rolled out on bottom rock a circle circle nearly singular integral broken hole, so that the shaft bottom of fixed cutting tooth be made to scrape section The change of change it is rough and uneven in surface, cutting tooth fixed in this way can wedging rock naturally, scrape and cut through rock.Two sets of cutting structure phase interworkings Under conjunction, efficiency of breaking rock of the drill bit in hard formation can be significantly improved.

Embodiment three

As shown in figure 17, the present embodiment is basically the same as the first embodiment, the difference is that, gear wheel 2 is disc cutter, i.e., Tooth 8 on gear wheel is the broken rock in a manner of complete static pressure, is formed in shaft bottom in continuous dise knife shape compared to embodiment two Continuous breaking tank.Extensional vibration of the drill bit in rock break-off process can be substantially reduced, while being reduced viscous under specific condition Sliding phenomenon.

Example IV

As shown in Figure 22,23, the present embodiment is essentially identical with embodiment one to three, the difference is that, at least there are two The body profiles line 32 of wing is the curve with local crowning 321, and the not overlapping region of each curve is distributed in the interior of drill bit Radial 2/3rds regions.Curve is the polymodal curve with multiple convex portions 321, along 32 cloth of wing body profiles line Tooth forms multiple step structure in center portion region.For composite drill bit, under the conditions of complex drilling, center portion region is opposite Weakness be easy to cause the initial failure of cutting tooth, in turn results in the failure of drill bit.The present invention can be good at reinforcing center portion region Cutting energy ability and service life, and then extend drill bit service life.

Embodiment five

As shown in figs. 18-21, the present embodiment and embodiment one to four are essentially identical, the difference is that, it is arranged on wing 3 There is second group of cutting tooth.In the present invention, first group of cutting tooth 41 that convex portion 321 is arranged, is to contact first with stratum Cutting tooth, the cutting tooth also worn at first.Interior inserted 42a is arranged in convex portion 321, and can further increase cutting tooth can Wear volume, and then extend bit life, as shown in figure 19.In addition, can also arrange another form of second group on wing Cutting tooth (the built-in inserted 42b of table), the built-in inserted 42b of table are arranged in empty slot 5, as shown in figure 19.Wherein, empty slot 5 can be Through slot as run through wing front and back sides in Figure 20 (a), is also possible to the groove such as wing leading flank recessed in Figure 20 (b).Make To be further preferred, the convex portion 321(local crowning of wing 3) and its near zone is provided with empty slot 5 and built-in table is inserted 42a, as second group of cutting tooth of drill bit, as shown in Figure 17,18.

Embodiment six

As shown in figure 24, the present embodiment is basically the same as the first embodiment, and difference is: the body profiles of the wing 3 Line 32 is the polymodal curve with multiple convex portions 321 (local crowning), and the local crowning of different wings is in same drill bit shaft It is mutually staggered in face, and corresponds to the wing cutting contour line and bit cutting contour line phase of wing body profiles line local crowning It cuts.The body profiles line 32 of any of the above-described wing is different from, at least two parts on the body profiles line 32 of the wing 3 The height of protrusion, local crowning is more than or equal to 2mm.

The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention Made any modifications, equivalent replacements, and improvements etc., should all be included in the protection scope of the present invention within mind and principle.

Claims (10)

1. a kind of composite drill bit suitable for bad ground, including drill body, the wing of opposite drill body consolidation is opposite to bore The gear wheel of head ontology rotation connection, and the hydrophthalmia or nozzle that are arranged on drill body, be provided on wing several first Group cutting tooth, the wing cloth flank of tooth are arranged recess and are connected to fix first group of cutting tooth, gear wheel by bit leg and drill body rotation It connects, tooth is installed on gear wheel, it is characterised in that: the body profiles line of at least one wing and at least another wing Body profiles line collectively cover in range have at least one not overlapping region and at least one coincidence point or be overlapped area Domain.

2. being suitable for the composite drill bit of bad ground as described in claim 1, it is characterised in that: at least there are two the sheets of wing Body contour line is the curve of whole or most of evagination, and each extra curvature convex domain vertex is along the radial position of drill bit radial direction Set difference.

3. being suitable for the composite drill bit of bad ground as described in claim 1, it is characterised in that: at least there are two the sheets of wing Body contour line is the curve at least one local crowning, and respectively has at least one local crowning along brill between the curve Head is radial or partly or entirely mutually staggers along bit cutting contour line.

4. being suitable for the composite drill bit of bad ground as claimed in claim 3, it is characterised in that: mutually wrong between the curve The local crowning opened is distributed in the radial zone other than drill bit one third radius.

5. being suitable for the composite drill bit of bad ground as claimed in claim 3, it is characterised in that: mutually wrong between the curve The local crowning opened is distributed in the radial zone within radial 2/3rds radiuses of drill bit.

6. as described in claim 1 be suitable for bad ground composite drill bit, it is characterised in that: be provided on the wing to Second not empty slot in group cutting tooth or at least one empty slot of few proud exposure less than or equal to zero, Huo Zhezhi Few second group of cutting tooth being fixed in empty slot.

7. the composite drill bit suitable for bad ground as described in any claim in claim 2 to 6, it is characterised in that: At least one exposure is disposed in whole or most of evagination or the corresponding wing region of local crowning on wing body profiles line Height less than or equal to zero second not in empty slot group cutting tooth perhaps at least one empty slot or at least one fix In second group of cutting tooth in empty slot.

8. being suitable for the composite drill bit of bad ground as described in claim 1, it is characterised in that: be equipped with wide edge on gear wheel Tooth, the value range of tooth top deflection angle are 70 °~90 °.

9. being suitable for the composite drill bit of bad ground as described in claim 1, it is characterised in that: gear wheel is disc cutter, disk Cutting tooth is in continuous dise knife shape on formula gear wheel.

10. being suitable for the composite drill bit of bad ground as described in claim 1, it is characterised in that: the body profiles line of wing The shape of local crowning be similar parabola shaped, trapezoidal, round, the combination of ellipse, diamond shape, rectangle or each shape.