EP0944765B1 - Drilling and/or coring tool - Google Patents

Description

The present invention relates to a tool for drilling and / or coring, in particular for drilling and / or oil coring, such as the preamble to the claim 1, as also disclosed in GB-A-2 204 625 or FR-A-2 620 487.

There is a constant need to increase the performance of such tools so that their penetration rates in the formations to be drilled or to be faster without reducing the duration of tool life, that is to say without unnecessarily increasing the load to which it is subject for the advance during operation.

It is wanted at the same time, to increase an average penetration speed, to increase the time a tool can be held in action in the same wellbore and / or core drilling, so as to avoid dead time for ascent, check, possible replacement of the tool and resumption of drilling and / or coring.

The object of the present invention is to improve the drilling and / or coring conditions known to this update and offers a tool which, on the one hand, provides a particularly advantageous arrangement and economical blades and cutting elements for avoid unnecessary regrinding of debris detached from the training and which, on the other hand, provides for a reserve cutting elements which will only be practically service and solicited only when needed, for example following the removal of a cutting element, possibly in PDC, located on a leading edge.

• des éléments coupants en PDC et/ou des éléments coupants secondaires qui présentent chacun une arête de coupe, formant ensemble le bord d'attaque de la lame, et dont l'axe longitudinal est transversal à l'axe de rotation, et
• au moins un élément coupant associé
  • qui est situé derrière, en considérant un sens de rotation de forage de l'outil, au moins un des éléments coupants en PDC ou secondaires,
  • qui présente une section transversale de même forme, du moins pour sa partie en saillie de la lame, que celle de l'élément coupant en PDC ou secondaire,
  • qui est disposé sur la même lame et
  • dont une arête destinée à la coupe est à au plus une même distance radiale de l'axe de rotation et à au moins une même distance, mesurée parallèlement à cet axe de rotation à partir d'un plan perpendiculaire à cet axe et situé en avant de l'outil 1, que l'arête de coupe de l'élément en PDC ou secondaire précité.

To this end, according to the invention, the aforementioned tool further comprises, outside of said central zone and on at least one blade,

• PDC cutting elements and / or secondary cutting elements which each have a cutting edge, together forming the leading edge of the blade, and whose longitudinal axis is transverse to the axis of rotation, and
• at least one associated cutting element
  • which is located behind, considering a direction of rotation of drilling of the tool, at least one of the PDC or secondary cutting elements,
  • which has a cross section of the same shape, at least for its projecting part of the blade, as that of the PDC or secondary cutting element,
  • which is arranged on the same blade and
  • of which an edge intended for cutting is at most the same radial distance from the axis of rotation and at least the same distance, measured parallel to this axis of rotation from a plane perpendicular to this axis and located in front of tool 1, than the cutting edge of the aforementioned PDC or secondary element.

According to one embodiment of the invention, the leading edge of the blades has the shape of a propeller with possibly variable radius and which, at least along said peripheral surface, turns either in opposite direction of the direction of drilling rotation either in the same direction as it moves away from the anterior face.

According to a particular embodiment of the invention, the width of a blade, taken in a projection plane perpendicular to the axis of rotation, increases as we move away from it, on the anterior face, and / or thereof in direction of a rear face of the tool. he can be advantageous while the number of cutting elements arranged one behind the other on the same blade and on of the same aforementioned distances, radial and parallel to the axis of rotation, increases progressively, in particular an element preferably of a length equal to that of the aforementioned cutting elements, as the width of the blade increases.

Other details and special features of the invention will emerge from the secondary claims and of the description of the drawings which are annexed to the present brief and which illustrate, by way of examples non-limiting various forms of embodiment of the invention.

Figure 1 shows schematically in a half plan view, as a tool, a head drilling of the invention.

Figure 2 shows schematically, in axial section, a superposition in the half-plane of section, after adequate rotation around the axis of rotation, projections of all cutting elements in PDC and secondary of the different blades of a tool drilling.

Figure 3 shows schematically in a half plan view, as a tool, a crown of coring of the invention.

FIG. 4 schematically represents, from the same way as that of FIG. 2 but simplified, projections of cutting elements in PDC circular and oblong secondary cutting elements of different blades.

Figure 5 shows schematically, in a partial plan view, another embodiment of a drill head as a tool of the invention.

Figure 6 shows schematically, at the as shown in Figure 4 but on another scale, a projection of the cutting elements in an axial half-plane various blades of a drilling head of the invention.

In the different figures, the same reference notations designate identical items or the like.

Tool 1 of the invention comprises so known, as shown in Figures 1, 2 and 3, a body 2 having a peripheral surface 3 substantially cylindrical and an anterior face 4 considering a direction of advance of drilling and / or coring. 5 extend from the anterior face 4 to the peripheral surface 3 and they each have a leading edge 6 for drilling or coring.

Sharp elements in PDC 7 (Poly-crystalline Diamond Compact or polycrystalline diamond tablet synthetic) are located at least in the area central 15A and are arranged so that their longitudinal axes are transverse to the axis of tool rotation 1.

Elements in PDC 7C can be distributed along the leading edge 6 of each blade 5; they each have a cutting edge 8 constituting together the leading edge 6.

According to Figure 1, these are elements secondary 10 which are distributed along each edge 6 and which each have an edge of section 8. It is also conceivable according to the invention any combination of secondary elements 10 and of PDC 7C elements along the same leading edge 6.

By secondary cutting element 10, one can hear here a cutting element arranged outside the central zone 15A, of which the cutting edge 8 is part from the leading edge 6. Such a secondary element 10 can be made by sintering and contain grains abrasives and a metallic binder.

Nozzles 9 (Figures 1 and 2, not shown in Figure 3) are usually provided on the front side 4 in order to provide through them a adequate liquid at the bottom of the well during operation.

According to the invention, the tool 1 includes plus, behind at least one cutting element in PDC 7C (Figure 5) or a secondary element 10 (Figure 1) in considering a direction of rotation of drilling S of the tool 1, at least one cutting element 10A associated with the element 7C or 10, which has a cross section of the same shape, at least for its projecting part of the blade 5, that that of the latter and which is arranged on the same blade 5 as the element 7C or 10 with which it is associated. Moreover, a cutting edge 11 of the associated element 10A is at plus the same radial distance R (Figure 2) from the axis of rotation and at least the same distance D, measured parallel to this axis of rotation from a plane P perpendicular to this axis and located in front of the tool 1, that the cutting edge 8 of the element in PDC 7C or secondary 10 associated. The associated item (s) 10A can therefore be set back from the elements 7C or 10 (Figure 6) regarding the training to drill or core.

So if the element in PDC 7C or secondary 10 wears or is torn from tool 1 or is broken, the associated element 10A, "sheltered" hitherto behind this element 7C or 10, can go into action and yield drilling and / or coring will hardly be affected not.

Figures 1 and 5 show for example that beyond a determined diameter around the axis of rotation, one or more associated elements 10A are thus behind each element in PDC 7C or secondary 10 arranged on the leading edge 6 of the same blade 5. We also see that the elements in PDC 7 and secondary 10 partners each time form a portion of ring centered on the axis of rotation.

The cutting elements in PDC 7 or 7C being usually mostly cylindrical, it can be preferred that secondary elements 10 and / or associated 10A are also and then advantageously present a diameter equal to that of the PDC 7C element corresponding. The diameters of the elements in PDC 7, 7C, secondary 10 and / or associated 10A can be either all equal be different from each other, by example depending on their distance from the axis of rotation.

In the case of the core bit 1 of FIG. 3, the closest cutting elements 10 of the axis of rotation are shown as having a same diameter and same orientation around this axis than the other cutting elements 10 located further from the axis of rotation. In addition, these 10 most relatives are represented as having a greater length to that of the other elements 10 located further of the axis of rotation. They could however have the same length as these. Usually the crown 1 does not include cutting elements made of PDC 7.

In the case of drill head 1 of the Figure 1, the most cutting PDC 7B cutting elements close to the axis of rotation are shown as being each oriented transversely (mounted by example on known intermediate supports) by relative to a corresponding axial plane. Elements in PDC 7C (Figure 5) such as those located on diameters greater than said diameter determined around the axis of rotation can also be mounted on the blades 5 so that their longitudinal axis is inclined by relation to a plane (that of the drawing) perpendicular to the axis of rotation, so that their end face with the cutting edge 8 is somewhat turned towards a downhole to be drilled or to the formation 17A to be drilled.

In the case of Figure 2, all the elements cutting in PDC 7C or secondary 10 and associated 10A have the same diameter and, on the same blade 5, the associated elements 10A located at the same radial distance R as the secondary element 10 or in corresponding PDC 7C are also at the same distance D, parallel to the axis of rotation, that this element in PDC 7 with respect to the plane perpendicular P.

The elements in PDC 7C, secondary 10, and associates 10A have been shown above as possibly be cylindrical (Figures 2 and 6). At least some associated elements 10A could however present other cross sections, for example oblong, elliptical or oval (Figure 4), the major axis of the oval or ellipse can then advantageously be substantially perpendicular to a plane tangent to an envelope 15B of the cutting elements 7, 10, 10A to the point of contact between the cutting edge 11 of the associated element 10A in question and this envelope 15B. Associated oblong 10A elements of this kind increase what can be called the volume of matter abrasive per unit of active surface of tool 1, being given the reservation that this accumulates deep into tool 1 and which can be used. It appears however that circular 10A associated elements increase already considerably this volume compared to the case so-called impregnated tools.

In tool 1 of the invention, it is preferred as cutting elements in PDC 7C (Figure 5) or secondary 10 (Figures 1 and 3) and the elements associated 10A neighbors are practically attached one to the other by their end faces facing one the other. Possible gaps between two elements 7C, 10, 10A neighbors and associates, resulting in example of the curvature of tool 1 seen in a plane intersecting perpendicular to the axis of rotation can be filled in the usual way in the trade (material infiltration, adequate sealant, etc.).

Advantageously, the leading edge 6 of each blade 5 of the tool 1 of the invention present in the whole a form of propeller, with variable diameter from the axis of rotation or from its most extreme close to it, on the anterior side 4, up to its opposite end located on the peripheral surface cylindrical 3 of body 2. This propeller can rotate either in the same direction either in the opposite direction to the direction of rotation S during drilling as it deviates of the axis of rotation and / or of the anterior face 4. By example, depending on what you want to evacuate fairly quickly debris from a well bottom by the cutting elements 7, 10, 10A we can make the blades 5 in the manner of an Archimedes screw or a helical drill bit as shown in the Figure 1. In addition, the leading edge 6, seen in plan, can start radially, or even in the direction of the tool rotation S near the axis of rotation and can then bend to go in the opposite direction of said direction of rotation S.

As shown in Figures 1, 2, 3 and 5, each blade 5 can project from the body 2 and present, as an external surface, a portion of the surface of revolution 12 in which elements are implanted cutting in PDC 7C or secondary 10 and associated 10A and which is delimited by anterior lateral faces 13 and posterior 14 (depending on the direction of rotation S in progress drilling or coring) which, in projection (Figures 1, 3 and 5), follow the shape of the propeller of a leading edge 6 correspondent. Thus the anterior lateral face 13A of a blade 5A follows the shape of the leading edge 6A of this same blade 5A while the posterior lateral face 14A of this blade 5A rather follows the shape of the edge 6B of the next 5B blade or a plot intermediate between those of the leading edges 6A and 6B.

Advantageously, the width of the portion of surface 12 and therefore the width of the blade 5, measured in a projection plane perpendicular to the axis of rotation, increases as one moves away from it on the anterior face 4 and / or that one deviates from this, on the peripheral surface 2, towards of a rear face 15 (FIG. 2) of the tool 1.

As the width of a blade 5 increases as above, the number of cutting elements associates 10A arranged one behind the other and behind a cutting element 7C, 10 on the blade 5, to the same level D taken parallel to the axis of rotation and by with respect to a plane P which is perpendicular thereto, can gradually increase by an associated element 10A. he may be preferred that all elements in PDC 7C and / or secondary 10 and / or associated 10A have the same length. However, it can also be advantageous, for example example to better follow the increase in width blades 5, at least some associated elements 10A of a blade 5 have different lengths, for example equal to half the length of the others cutting elements 7C, 10, 10A arranged in line at a same level D on a slide 5.

Secondary cutting elements 10 and / or associates 10A are advantageously made in one cheaper material than that of PDC 7 elements. secondary elements 10 and / or associated 10A are by example made of a composite material containing abrasive particles. It can be carbide sintered or infiltrated tungsten known to man of the loom, and possibly including particles of diamond.

Certain so-called associated elements 10A can however also be made in PDC and arranged by example between two other associated elements 10A in composite material cheaper than PDC, in the same line at the same level on a blade 5. Elements secondary 10 and / or associated 10A can also be made in what is called in the profession of thermostable synthetic diamond.

Secondary elements 10 and / or associated 10A can have a different hardness between them, for example according to their position on tool 1, and may also contain percentages (by volume) variable in abrasive and / or diamond particles.

As shown in particular in Figure 1, at least one blade 5 can extend into an area central 15A of the front face 4 and one of the blades 5 may present a cutting element in PDC 7B which acts practically in the center of this face 4. In this area central 15A, the blade (s) 5 may preferably not have only PDC 7B cutting elements without associated cutting element 10A. For example, blade 5A can be closer to the axis of rotation than the others blades 5 and have a reduced width in this area central 15A.

Other blades, like the 5B can start outside the central zone 15A and have as soon as they start a width such as several cutting elements 7C or 10 and 10A can be arranged online at a first level D most anterior on this blade 5B.

Spaces can be made between the various blades 5 on the front side 4 to accommodate them nozzles 9. Drilling fluid conduits (Figure 1) and / or coring can be provided so usual in tool 1. The outlet nozzles 9 of this liquid can be of a type to be screwed into tool 1 so as to be exchangeable according to their dimensions flow and therefore the flow of liquid to the bottom of a well being drilled.

Nozzles 9 can however be made up of prefabricated elements. So when the manufacture of a tool 1 by molding, these elements prefabricated can be installed in locations provided in the mold at the same time as they are placed, in adequate locations, cutting elements in PDC 7, secondary la and associated 10A. The mold is then filled in the usual way with solid elements and powdered materials which constitute in a known manner itself, after infiltration of a liquid metal in this mass, the body 2 and the blades 5 proper, the liquid metal then fixing the elements at the same time prefabricated and cutting elements 7, 10, 10A aux blades 5 thus produced.

Of course, from one blade 5 to another, the cutting elements 7, 10, 10A are arranged at levels D and distances R from the axis of rotation chosen so that projection in a plane passing through the axis of rotation (Figures 2, 4 and 6), the cutting elements 7, 10, 10A are complement each other to form at the bottom of a well drilled or cored a 15B envelope with leading edges 6 as regular as possible, without leaving high circular projections 16 between two circular grooves 17 cut by the cutting edges 8, 11 of the assembly leading edges 6 in formation 17A to be drilled or carotter.

It should be understood that the invention is not in no way limited to the embodiments described and that many modifications can be made to these last without departing from the scope of the present invention.

Thus the front face 4 of the tool drilling 1 (figure 2) is preferably concave in the central zone 15A and the cutting elements 7, 10, 10A are arranged so as to cut a bottom of the hole substantially conical drilling with a slight slope, for example between 10 ° and 30 °, relative to a perpendicular plane at the axis of rotation, the cone pointing towards the end back 15 of tool 1 in working position. A 20 ° slope may be preferred.

In addition, the blades 5 in a helix are advantageously arranged on the peripheral surface 3 of so that, seen according to the projection of FIG. 1, a blade 5A covers the rear end 18F of a 5F blade which extends (in the case of this figure) along arrow 19A to below the part visible from slide 5A in this view, and the same for others. So continuity is assured, without shock, a bearing (thus improved) of tool 1 against a wall for example of the well being drilled.

In the projection of figure 1, the propeller described in the case of the drilling tool 1 can be considered to be a portion of a spiral, on the front side 4, followed by a properly propeller said on the peripheral surface 3.

A channel 19 (Figures 1 and 2) is provided each time between two blades 5 and, advantageously, it widens at least from its furthest end close to the axis of rotation and possibly up to reach a specific width, for example as that the blades 5 which surround it widen.

Secondary cutting elements 10 and / or associates 10A preferably have their end faces 20 (anterior and / or posterior) parallel to the axis of rotation of the tool 1. These end faces 20 can form an angle with a radius starting from this axis rotating and going through any of their points.

Application of the invention to a crown coring is understandable on reading the above and examining the corresponding figure 3 in which any nozzles of coring liquid were not represented. We see in particular a radial distance offset from first cutting element 10 of a blade 5 relative to that of the next, and so following cutting elements 10, 10A on each blade 5. The elements closest to the axis of rotation can be arranged with their longitudinal axis perpendicular to the axis of rotation, such as this is represented, or having a particular inclination so that the cutting edge 8 forms with the formation 17A to dig a determined cutting angle.

LIST OF REFERENCES

1

Tool

2

Body

3

Peripheral surface of 2

4

Front side of 2

5

Blade (of which the blades 5A are indicated in particular, 5B, 5F)

6

Leading edge of 5 (and which is indicated in particular the edges 6A, 6B of the corresponding blades)

7

Cutting element in PDC (which is also indicated variants 7B and 7C according to their positions related)

8

Cutting edge of 7, 10

9

Nozzle

10

Secondary cutting element

10A

Associated cutting element

11

10A cutting edge

12

Portion of surface of revolution of 5

13

Anterior lateral face of 5 (which is indicated in especially the 13A of the corresponding blade 5A)

14

Posterior lateral face of 5 (which is indicated in especially the 14A of the corresponding blade 5A)

15

Back side of 1

15A

Central area of 4

15B

Envelope

16

projections

17

furrows

17A

Training

18

Posterior end of 5 (which is indicated in particular 18F of the corresponding 5F blade)

19

Channel

19A

Arrow

20

10, 10A end faces

P

Perpendicular plane, in front of tool 1

D

Distance from P

R

Radial distance

S

Tool rotation direction 1.

Claims (15)

1. A drill or core tool, in particular for oil drilling or coring, comprising :

   a body (2) showing a substantially cylindrical peripheral surface (3) and a front face (4), considered in a forward movement direction during drilling or coring,

   blades (5) which extend from the front face (4) till over the peripheral surface (3) and which show each a leading edge (6) for the drilling or coring,

   possibly PDC cutting elements (7) which are situated at least in a central area (15A) of the front face (4) and the longitudinal axes of which are transverse to the rotation axis of the tool (1), and

   outside said central area (15A) and on at least one blade (5),

   leading cutting elements (7C, 10), chosen between PDC cutting elements (7C) and secondary cutting elements (10), each with the shape of a small plate, which show each a cutting edge (8), forming together the leading edge (6) of the blade (5), and the longitudinal axis of which is transverse to the rotation axis, and

   at least one associated cutting element (10A) which is situated, when considering a rotation direction (S) of the tool (1), behind at least one of the leading cutting elements (7C, 10)and which is disposed on the same blade (5),

   characterized in that the associated cutting element (10A)

   shows a shape of a small plate with a cross-section of the same aspect, at least for its portion protruding from the blade (5), than that the leading cutting element (7C, 10),

   comprises, for the cutting, an edge (11) situated at the most on a same radial distance (R) from the rotation axis and at least on a same distance (D), measured parallel to this rotation axis starting from a plane (P) perpendicular to this axis and situated in front of the tool (1), than the cutting edge (8) of said leading cutting element (7C, 10), and
   is practically coupled by an end face to an adjacent end face of the leading cutting element (7C, 10) or of another associated cutting element (10A), situated immediately next thereto o the same blade (5).
2. A drill or core tool according to claim 1, wherein a portion of each associated cutting element (10A) is buried in the blade (5) to secure it to the bit body (2) and wherein, preferably, the associated cutting element (10A) thus secured has a substantially uniform thickness and a cross section, taken along a plane disposed at a right angle to said longitudinal cutter axis, that is substantially circular, oblong, elliptic or oval with a correspondingly shaped cutting face which is at least partially presented to the formation in the direction of tool rotation.
3. A drill or core tool according to claim 1 or 2, characterized in that the secondary (10) and/or associated (10A) cutting elements are elements which are prefabricated by sintering and which comprise abrasive grits and a metallic bond.
4. A drill or core tool according to any one of the claims 1 to 3, characterized in that the PDC cutting elements (7) and/or the secondary (10) and/or associated (10A) cutting elements are cylindrical and have preferably equal diameters.
5. A drill or core tool according to any one of the claims 1 to 4, characterized in that the leading edge (6) of the blades (5) has the shape of a helix with a possibly variable radius and which turns, at least along said peripheral surface (3), either in the direction opposite to the drilling rotation (S) or in the same direction as it moves away front the front face (4).
6. A drill or core tool according to any one of the claims 1 to 5, characterized in that the width of a blade (5), taken in a projection plane perpendicular to the rotation axis, increases as one moves away from this rotation axis over the front face (4), and/or from this front face in the direction of a back face (15) of the tool (1).
7. A drill or core tool according to claim 6, characterized in that the number of associated cutting elements (10A) arranged one behind the other on a same blade (5) and on the same of said distances (D, R) radial and parallel to the rotation axis, increases progressively, in particular with one associated cutting element (10A) having preferably a length equal to the length of said secondary cutting elements (10), as the width of the blade (5) increases.
8. A drill or core tool according to any one of the claims 1 to 7, characterized in that secondary (10) and/or associated (10A) cutting elements are made of a composite material containing abrasive particles.
9. A drill or core tool according to any one of the claims 1 to 8, characterized in that secondary (10) and/or associated (10A) elements are thermally stable synthetic diamonds.
10. A drill or core tool according to any one of the claims 1 to 9, characterized in that the nozzles (9) are composed of prefabricated elements placed in locations provided in a production mould, at the same time as the PDC (7) and/or secondary (10) and/or associated (10A) cubing elements are placed in the mould, the mould being subsequently filled with solid elements and powdery materials which form, after infiltration with liquid metal, the body (2) and the actual blades (5).
11. A drill tool according to any one of the claims 1 to 10, characterized in that at least one blade (5) extends in the central area (15A) of the front face (4) and comprises at least one of the PDC cutting elements (7) arranged for acting in the middle of this front face (4), the cutting edge (8) of this PDC cutting element (7) pertaining to the leading edge (6) of said blade (5).
12. A drill and/or core tool according to any one of the claims 1 to 11, characterized in that at least one associated cutting element (10) has an oblong cross-section and in that the largest dimension of this cross-section is preferably directed substantially perpendicularly to a plane tangential to an envelope (15B) of the cutting elements (7, 10, 10A) of the place of contact between the cutting edge (11) of the concerned associated element (10A) and said envelope (15B).
13. A drill or core tool according to any one of the claims 1 to 12, characterized in that the longitudinal axis of at least certain of the PDC (7) and/or secondary (10) cutting elements shows an inclination with respect to a plane perpendicular to the rotation axis in such a manner that their end face comprising the cutting edge (8) is turned somewhat to a bottom of the hole to be drilled.
14. A drill or core tool according to any one of the claims 1 to 13, characterized in that the longitudinal axis of at least certain secondary (10) and/or associated (10A) elements is comprised each time in a plane perpendicular to the rotation axis.
15. A drill tool according to any one of the claims 1 to 14, characterized in that, in the central area (15A), the front face (4) is concave and in that the cutting elements (7, 10, 10A) are disposed therein to cut out a drill hole bottom of a substantially conical shape with a low gradient with respect to a plane perpendicular to the rotation axis.

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