• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
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    • 专利摘要:
    18Summary:Drill bit (1) for striking rock drilling comprising a connecting part (2) for co-operation with a drill rod and a fatherintervention against rock designed and in a felling direction (A)directed felling part (3) with a plurality of frontal projectionspins in the form of rock processing inserts, said pins being distributed in the radial direction as well as in the pivot joint in relation to a main axis (H) for the drill bit, and the drill bit having a flushing channel opening frontally in the felling part (4)for forward transport of flushing medium. In a central frontalarea (C) of the felling part opens said spool channel (4) with an edge (5 ") of a mouth portion (5) adjacent to said main shaft and is an inclined pin (6) so arranged that a longitudinal axis (L) of the inclined pin forms a pointedangle (a) with a longitudinal direction of the drill bit (1), and that aFor engagement with rock intended felling end (7) of the inclined pin protrudes so that a surface area (8) of the felling end is located in connection with partly the said mouth portion (5) and partly the said main shaft (H).Fig. 1
    公开号:SE1250571A1
    申请号:SE1250571
    申请日:2012-06-01
    公开日:2013-12-02
    发明作者:Goeran Stenberg；Tommy Stahre；Thomas Oesterholm；Alexander Beronius；Jimmy Carlsson
    申请人:Atlas Copco Secoroc Ab；
    IPC主号:
    专利说明:

    1BORRKRONAFIELD OF THE INVENTIONDangerous invention refers to a drill bit father strikingrock drilling comprising a plurality of frontal projectionspin in the form of rock processing inserts, the drill bit having a flushing channel opening in front of the felling part for forward transport of flushing medium.
    BACKGROUND OF THE INVENTIONPin drill bits for rock drilling include a number of cemented carbide pins inserted into a body in which one or more flushing channels are usually arranged to transport flushing medium from the inside of the hollow drill rod tothe front of the drill string.
    The flushing medium then flows via flushing channels in the front part of the drill bit for continuous removal of crushed rock. The crushed rock is then typically transported along the cradle of the formed drill tail outside the drill string up tothe mouth of the tail.
    In order to reduce the pressure drop, flushing medium passes through flushing channels in the drill bits and in the case of seeking to obtain efficient flushing of the front of the drill bits, usually two or more flushing holes arranged opening in the drill bits.front. Even the side coil hall occurs in traditionaldrill bits.
    Examples of the background of the technology are:US 3,941,197, in which an inclined flushing channel opens into a frontal area of the drill bit.
    US 4,069,880, which describes a drill bit with a flushing channelopening into the front and with axially directed pins distributed Over the front surface of the drill bit.77195 201204182ANDAMAL AND MOST IMPORTANT CHARACTERISTICS OF THE INVENTIONIt is an object of the invention to provide a drill bit of an initially named type, which constitutes a further development of known drill bits of the type which exhibita flushing channel opening in front of the felling partforward transport of flushing medium to the front of the drill bit. The crushed rock is then carried away along the cradle of the formed drill hole outside the drill string up to the mouth of the hazel.
    This andamal is achieved at a drill bit of initiallyndmnt kind by being in a central frontal area ofthe felling part:said flushing channel opens with an edge of a mouth portion adjacent to the main shaft of the drill bit, andan oblique pin there arranged so that a longitudinal axis for itthe oblique pin forms an acute angle with alongitudinal direction of the drill bit, and that a single engagement with rock intended felling end of the inclined pin protrudes so that a surface area of the felling end is located in connection with partly the said mouth portion and partly the said main axis.
    In this way, a number of advantages are obtained in comparison withdrill bits whose flushing channels open at a distance from the main axis get the drill bit. At such previously known drill bits, and in particular at drill bits, in which a plurality of flushing holes open in front of the drill bit, a so-called dad zone arises, to whichthe flushing rather feeds on transports away harvestedmaterial. In contrast to these traditional drill bits, the invention provides more efficient flushing and thus better conditions for efficient felling.
    By avoiding that harvested material is washed awaymore efficiently and in particular do not accumulate in this dada zonedoes not require impact energy to be used to perform blows against and grind such already harvested material, but itassured in an effectively put greater opportunities father77195 201204183the drill bit to act against rock ± form of non-crushed material. This also entails reduced wear for a drill bit according to the invention.
    More efficient flushing is also possible in relative termsless energy is required for the flushing. This leads to a betterwith an existing flushing pump for a rock drilling plant as well as in connection with dimensioning of new plants. The invention also makes it possible to adapt the flushing channel of the drill bit so that the river resistance can to a large extentreduced.
    The invention achieves that the flushing channel can be allowed to open near the center axis in the front of the drill bit without the risk of a remaining central rock plug being created during drilling, which could otherwise drop to aflushing channel opening.
    This is achieved by the inclined pin, which can be placed in close proximity to the mouth, in that the root portion of the inclined pin is directed in a direction away from the flushing channel. This arrangement ensures stable andeffective holding of this inclined pin withoutsurrounding material in the drill bit needs to be influenced on the course of the flushing channel.
    Due to the location of the inclined pin, it is said that a surface area of the felling spirit is adjacent topartly the said mouth portion, partly the said main shaft in combinationwith the nearest centrally located mouth of the flushing channel, it is ensured that this pin, like other pins inputting in the drill bit, acts directly against crushed rock in the rock formation intended for drilling, which givesmore efficient and thus more economical drilling.
    The indication of the location of the inclined pin with said surface area ± connection to the main shaft means that any surface portion thereof should not be at a greater distance from77195 201204184the main axis indicates that efficient rock felling takes place by the oblique pin in practice acting directly on rock not yet felled. This avoids energy AtgAr for blows to already decomposed rock pieces.
    Flushing in direct connection to the center of the drill bit entails, as discussed above, general advantages in terms of wear reduction, more efficient drilling and reduced energy consumption for sAval drilling as flushing.
    It is an advantage that the flushing channel has onecross-sectional area, which does not decrease according to its extent, butPreferably, the cross-sectional area of the flushing channel according to its length up to the outlet orifice in the front surface of the drill bit is essentially the same cross-sectional area over its length. More dangerous is the cross-sectional area of the flushing channel at least equalstands as the area of the drill bit tapphAl because this gives aadvantageously LOW flow resistance gets the flushing fluid. Most preferred is that the cross-sectional area of the flushing channel plows continuously or in steps along the extent of the flushing channel as this provides the best flow conditions for the surface.
    TapphAlet has A on its side Lecture At least the samecross-sectional area as a flushing channel in a drill string, with which the drill bit is connected.
    It has further been found that it is generally of great importance in drill bits of the type to which the inventionhanfors, that the flushing channel is designed with a sufficient starcross-sectional area (flush channel area - S) in relation to an area of a borehole (borehole area - B), which is created during the operation of the drill bit. Surprisingly, it has been found that relatively small changes in this ratio in the direction of a reduction ofThe S / B ratio entails significant pressure drop increases, whichentails a coil coil effect and thus a risk of less efficient drilling.77195 20120418For a better understanding of this aspect, it can be called thatat a drill bit with a diameter of 76 mm and at a certain flow as a comparison only:S / B = 0.060 gives a pressure drop of 1.8 barS / B = 0.047 gives a pressure drop of 2.4 barS / D = 0.028 gives a pressure drop of 5.2 barA generally preferred value S / B is probably Over0.05.
    Total cross-sectional area of the total channel Over tapphAlet -flushing channel - free area between the front of the drill bit andthe bottom of the drill tail - free area past the front towards the periphery of the drill bit - free area between the drill bit and the drill hole The cradle should not show any reduction or throttling after its course as this causes increased pressure drop and reducedrinsing effect.
    The most important thing in this context, however, is that the area is maintained in the sialva drill bit, ie. along the course of the spighal - flushing channel, whereby especially the area of the flushing channel must be sufficiently large, as above.
    Comparative attempts have given at hand that a flushing channelformed with the same cross-sectional area according to its extent and In accordance with the tapping holeCauses a pressure drop, which is only about one third of a common pressure drop Caused by a flushing channel in a cheek drill bit with flushing channel(s) with smaller total cross-sectional area. The invention itselfIt is also possible for an efficient way for the flushing channel to be designed with a comparatively very rigid cross-sectional area without sacrificing the felling function.
    In view of the above, concerning itthe position of the inclined pin in relation to the main axis,The mouth portion 14mplically mentioned is located substantially opposite the oblique pin in relation to the main axis, since in this case a location toAtande large cross-sectional area of77195 201204186the flushing channel with small flow-preventing angular deviations along its extension is allowed.
    It is preferred that the oblique pin pull a pin offthe type specified in WO 2011/043717, which furthercontributes to good longevity and non-existent or At leastreduced regrinding need.
    It is preferred that the longitudinal axis of the inclined pin forms an acute angle with said main axis since thereby the material utilization of the inclined pinroot portion is optimized and the cross-sectional area of the flushing channel is notlimited.
    Lampligen ars said pointed angle between ° and 70 °. More preferred is the said acute angle between ° and 5 °. Most preferred is the said acute angle between ° and°. In particularly preferred embodiments, the followingacute angles set to ° and °, respectively.
    The oblique pin is preferably made from a bevelled front surface portion of the felling part as this simplifies the manufacture of the drill bit. The chamfering is ldmpligenmade at an angle corresponding to the aforesaid acute angleIt is preferred that, seen in the felling direction, the inclined pin is coated Aterdraget in relation to other pins of the drill bit as this gives a lower degree of load on the inclined pin in operation of the drill bit.
    In a preferred aspect of the invention, protrudingthe inclined pin so that it is with said surface area located in close proximity to said main shaft, at a distance from the main shaft which is dimensioned corresponding to a width of a predetermined crushing zone formed when usingthe drill bit in a rock type intended for this. Hdrigenom canthe mouth portion of the flushing channel is advantageously increased in size by allowing a corresponding piece to be moved in the direction of the inclined pin so that the mouth portion77195 201204187even includes the main shaft. It should be emphasized that within the scope of the invention, the inclined pin is positioned so that it with said surface area is in direct connection with, or tangential to, said main axis. The az-In accordance with the scope of the invention, the inclined pinis positioned so that with said surface area it encloses said main shaft, i.e. said that the main axis runs through the oblique pin.
    Lamply, the felling part has a frontat least one substantially radially overlapping coil pairemanating from the said estuary and in principle from the main shaft. This design of coil pairs provides smooth and unobstructed removal of felled material from the front of the drill bit. It should be emphasized that other configurations offrontal and lateral coil pairs dr possible and t.o.m.drill bits of the "flat face" type, i.e. completely without frontal coil pairs.
    Preferably, the said mouth portion is a transversely elongated, oval, rounded half-man-shaped or full U-shapedformat hall. Adjacent to an edge of the mouth portionThe above-mentioned surface area of the inclined pin is located because this design allows a good distribution of flushing fluid over the front of the drill bit. This design also provides a reduction in flow resistance in this areaof the flushing channel. When the said mouth portion consists of onelong-stacked haul, the said surface area of the inclined pin is preferred in connection with one long side of the haul.
    The drill bit has, in addition to the aforementioned inclined pinspreferably also a first set of peripheral pins, whichare directed in diverging directions, seen in the felling direction, and a second set-up, seen in a radial joint for the drill bit intermediate pins, which are77195 201204188arranged with their longitudinal axes substantially parallel to the major axis.
    It is preferred that a plane through the major axis forms a plane of symmetry for the inclined pin and the mouth portion,because this allows the mouth location and size to be designedin the direction of optimization taking into account the position of the inclined pin since the pin can then be placed closer to the main axis. As can be understood from the above, however, it is perfectly possible to arrange the inclined pin side-by-side asuch a plane of symmetry if it would be appropriate by something elseshall sasom of space shells.
    Additional features and benefits are set forth in the following detailed description.
    BRIEF DESCRIPTION OF THE DRAWINGSThe invention will now be described in more detail with reference to exemplary embodiments and with reference to the accompanying drawings, in which:Fig. 1 shows a drill bit according to the invention in oneaxial section,Fig. 2 shows the drill bit in Fig. 1 in a front view,Figs. 3a, 3b, 3c and 3d show front views of alternativelydesigned drill bit according to the invention, andFig. 4 shows the drill bit in Fig. 1 in operation in an axialcut.
    DESCRIPTION OF EMBODIMENTSFig. 1 shows an axial section through a drill bit 1 according to the invention, which has aconnection part 2 for cooperation with a drill string (not shown) anda felling part 3, which in use is directed in a felling direction direction A and by impact and77195 201204189intermediate rotation in and of itself} cant sat there set upto crush and fell rocks form a borehole. In the connection part 2 years in the usual way, a honganga is set up for receiving a hanger aisle mounted on adrill string component.
    In the felling part 3 the drill bit 1 has a flushing channel 4, which extends from the interior of the connecting part, where the flushing channel 4 connects via a pinhole 4 to a central channel in a drill string component (not shown), through whichflush fluid is fed on in and of itself} cant sat. The flushing channel 4opens into a, outlet in the form of a mouth portion 5 in front of the felling part 3, and furthermore the mouth portion 5 is so coated that an edge thereof, 5 ', is coated in close or direct connection to a main axis H fordrill bit.
    An inclined pin 6 is arranged with a longitudinal axis L forming an acute angle α with the main axis H. The inclined pin has a direction so that an engagement with rock intended cutting end 7 projects so that a surface area 8 thereofare located in direct connection to the said edge 5 'ofsaid orifice portion 5, partly of said main shaft H.
    The inclined pin 6 will thus act centrally in the rock portion, in principle in the form of a cylindrical rock body, constituting what is to be drilled.with the drill bit meets the intended drill tail. That in thisbody centrally coated rock material will then be felled through the inclined pin. The inclination means that the root portion of the inclined pin 6 can be placed so that the flushing channel 4 can advantageously be pulled close to the main axis H withoutthe integrity of the mounting for the inclined pin 6adventures.
    In addition to the inclined pin 6, the drill bit 1 according to the invention has a first set of peripheral pins 11,77195 20120418which are distributed extremely along the periphery of the drill bit and are directed with their respective longitudinal axes L 'in diverging directions seen in the felling direction A and a second set of intermediate pins 12, intermediate seen in aradial joint for the drill bit, which intermediate pins 12 arearranged with their longitudinal axes L "substantially parallel to the major axis H.
    Seen in the felling direction A, the oblique pin 6 is coated Aterdraget in relation to At least the otherthe set pin 12, which causes it to be inclinedthe pin will be subjected to reduced load use of the drill bit as it will crush less rock. This in turn meant that regrinding of the oblique pin did not behave at all or at least did notneeds to be performed as often as is the case if the pins in itfirst and second set, respectively. This is also an advantage because the oblique placement makes regrinding more responsive.
    Advantageously, the inclined pin 6 can normally also be made smaller than the other pins, especially if it is designedin accordance with the above-mentioned WO 2011/043717, which alsoadvantageously the fastening of this inclined pin gets the drill bit.
    The front view in Fig. 2 shows the elongated, possibly oval shape of the mouth portion 5 and two substantiallyradially extending coil track 10 starting from the saidorifice portion 5 and extending to the periphery of the drill bit, after which continuation coil pairs not shown with axial passage connect.
    A plane through the line A1, which plane passes throughthe main axis H, forms the plane of symmetry of the inclined pin,for the flushing channel 4 and for the mouth portion 5 as well as generally for the drill bit 1 in this embodiment of the invention.77195 2012041811Figs. 3a, 3b and 3c show three other embodiments of a drill bit according to the invention, all of which differ from that shown in Figs. 1 and 2 in that the mouth 15 of the flushing channel is formed more circularly than is the case withthe drill bit according to Figs. 1 and 2. The shape can be characterized as"Fully U-shaped" with raised end portions so that an inner edge 15 of the mouth 15 encloses a large part of the inclined pin 6 centrally around the main axis H.
    In the embodiment in Fig. 3a it is inclinedthe pin 6 placed so that it is located with the said surface area 8directly adjacent to and tangential to said major axis H.
    In the embodiment in Fig. 3b, the inclined pin 6 is placed so that it with said surface area 8 is located insideadjacent to the main axis H, at a distance frailthe main shaft which is dimensioned so that when using the drill bit in a rock type intended for this, the pin 6 will operate in unmilled material in accordance with what is discussed above.
    In the embodiment in Fig. 3c, the oblique figurethe pin 6 placed so that with the said surface area 8 it encloses the said main shaft H, i.e. saw that the main axis H passes through the inclined pin 6.
    In the embodiment in Fig. 3d is as inthe embodiment in Fig. 3a the inclined pin 6 placed sothat with said surface area 8 it is located in direct connection to and tangential to said main axis H. In addition, the drill bit in Fig. 3d has a further inclined pin 6 ', which is placed adjacent to and slightly projecting.edge of the mouth portion 5 of the flushing channel. This furtherInclined pins 6 'are preferably at the same axial level as the pin 6 but not located adjacent to the main shaft, as the pin 6. The additional inclined pin 6' can77195 2012041812especially with drill bits of larger dimensions contribute to a good sand splitting effect on rock material in a central area, and thus increase the service life of the inclined pin 6. It is not excluded that more than one additional inclined pin isdistributed around the mouth portion in the front of the drill bit andplaced in a similar way as the pin 6 '.
    Fig. 4 shows the drill bit 1 in Fig. 1 in a tank operating layer acting against a schematically illustrated rock portion 13, to illustrate that the inclined pin 6 isRetraction in relation to the intermediate pins 12.
    The significance of this has been discussed above.
    The invention can be varied within the scope of the followingthe requirements and the number of pins inserted in the drill bit can be varied according to the size of the drill bit and according to the area of usefor the drill bit.
    The inclined pin can advantageously be placed at a distance from the main shaft, which of course a axis of rotation carries the drill bit, and extends the shaft around which the pin,including the oblique pin, describes a rotatingmovement in the use of the drill bit.
    As discussed above, preferably this distance corresponds to the width of a crushing zone, i.e. the width, or in other words the depth of a zone of crushed material, which is crushed and thus felled by a blow of the drill bit. Thismajliggor centered location of the estuary portion ofthe flushing channel without the risk of a remaining non-crushed part of the rock arising, such as a harmful central rock pin, which could jeopardize the function and reduce the efficiency of the drill bit and in particular the flushing.
    The indication cm location of the oblique pin indirect connection to the main axis can thus be related to the fact that some surface portion thereof should not be at a greater distance from the main axis than the depth of said crushing zone in the rock, which77195 2012041813generated during the operation of the drill bit. The depth of the crushing zone depends on several parameters, of which rock hardness and delivered impact energy can be mentioned as examples. For normal conditions in medium-hard rock can normally be traced to the depth of the crushing zonec: a 1.5 - 2 mm. Normally, therefore, the distance between the main axis livesand most adjacent surface portion of the oblique pin does not substantially exceed these values.
    Less river resistance for flushing fluid entails the need to store flushing pressure, which i.a. a. leads to smaller friction lossesand reduced pump power requirements.
    Tests with a drill bit according to the invention have given positive results both in terms of drilling speed, which has been able to be increased by about 10%, and service life, which has been able to be increased by more than 30% due to reduced wear, compared to atraditional drill bit with an otherwise corresponding design.77195 2012041814
    权利要求:
    Claims (18)
    [1]
    Said spool channel (4) opens with an edge (5 ') of an orifice portion (5) adjacent to said main shaft, and 2. an inclined pin (6) is arranged so that a longitudinal axis (L) forms the inclined pin an acute angle (a) with a longitudinal direction for the drill bit (1), and that a felling end (7) intended for engaging with rock of the inclined pin projects so that a surface area (8) of the felling end is adjacent to the said mouth portion (5), partly ndmnda main shaft (H).
    [2]
    Drill bit according to claim 1, characterized in that said mouth portion (5) is located substantially opposite the inclined pin (6) in relation to the main shaft (H).
    [3]
    Drill bit according to claim 1 or 2, characterized in that the longitudinal axis (L) of the inclined pin (6) forms an acute angle (a) with said main axis (H).
    [4]
    Drill bit according to claim 1, 2 or 3, characterized in that the inclined pin (6) emanates from a chamfered front surface portion (9) of the felling part (3).
    [5]
    Drill bit according to one of Claims 1 to 4, characterized in that, seen in the felling direction (A), the inclined pin (6) draws the coated retraction in relation to other pins (12) of the drill bit (1).
    [6]
    Drill bit according to any one of claims 1 - 5, characterized in that said acute angle (a) is between ° and 700 °.
    [7]
    Drill bit according to claim 6, characterized in that said acute angle (a) is between ° and °.
    [8]
    Drill bit according to claim 7, characterized in that said acute angle (a) is between ° and °.
    [9]
    Drill bit according to any one of claims 1 - 8, characterized in that the inclined pin (6) projects so that it with said surface area (8) is located at a distance from said main axis (H) which is dimensioned corresponding to a width of a related crushing zone arising from the use of the drill bit in a rock type intended for this.
    [10]
    Drill bit according to any one of claims 1 - 9, characterized in that the felling part (3) has a frontal at least one substantially radially extending coil pair (10) emanating from said mouth portion (5).
    [11]
    Drill bit according to any one of claims 1 - 10, characterized in that said orifice portion (5) consists of an elongated hall, in connection with which one longitudinal said surface area (8) of the inclined pin (6) is located. 77195 20120418 16
    [12]
    Drill bit according to any one of claims 1 - 10, characterized in that said mouth portion (5) consists of an oval, rounded half-man-shaped or full U-shaped hall.
    [13]
    Drill bit according to one of Claims 1 to 12, characterized by the flushing channel (4) extending with substantially the same cross-sectional area over its length.
    [14]
    Drill bit according to any one of claims 1 - 13, characterized in that the inclined pins (6) mentioned above have a first set of peripheral pins (11), which are directed in diverging directions, seen in the felling direction (A) and a second set, seen in a radial joint for the drill bit intermediate pins (12), which are arranged with their longitudinal axes substantially parallel to the main axis (H).
    [15]
    Drill bit according to one of Claims 1 to 14, characterized in that a plane (A1) through the main shaft forms a plane of symmetry for the inclined pin and the mouth portion.
    [16]
    Drill bit according to any one of claims 1 - 15, characterized in that at least one further inclined pin (6 ') is placed adjacent to an edge of the mouth portion (5).
    [17]
    A drill bit according to any one of claims 1 - 16, characterized by the flushing channel (4) after its length up to an outlet opening in a front surface of the drill bit has substantially the same cross-sectional area over its length as a cross-sectional area of a pinhole of the drill bit.
    [18]
    Drill bit according to claim 17, characterized by a relationship between the cross-sectional area (S) of the flushing channel (4) and a cross-sectional area (B) of a drill bit generated by the drill bit in operation at At least 0.05. 77195 20120418 N61 z _5 / 9E- g: v _5 / 1
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    同族专利:
    公开号 | 公开日
    SE537726C2|2015-10-06|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    SE1250571A|SE537726C2|2012-06-01|2012-06-01|Drill bit for striking rock drilling|SE1250571A| SE537726C2|2012-06-01|2012-06-01|Drill bit for striking rock drilling|
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