FR3020089A1 - DEVICE FOR DRILLING THE GENUS TREPAN EMULSEUR - Google Patents

Abstract

The present invention relates to a drilling device (1) of the trepan emulsifier type comprising a tubular structure (2) which comprises an elongate body (3) and an interchangeable drill head (4). The drill head (4) and the lower end (33) of the elongated body (3) have complementary structures (5) which are adapted to the removable assembly of said drill head (4) on said lower end (33). ) of the elongated body (3), and said complementary structures (5) are fixed together by means of removable fastening means (6)

Description

TECHNICAL FIELD TO WHICH THE INVENTION RELATES The present invention relates to the field of public works; it relates in particular devices of the trepanan type emulsifier, for drilling wells in the ground.

BACKGROUND The foundations of certain buildings and structures, called "deep foundations", consist of poles (or "piles") that support the deep layers of the ground.

A deep foundation is characterized by the way in which the floor is urged by the poles to resist applied loads: tip resistance and / or lateral friction. There are many techniques for achieving such deep foundations.

The so-called "driven pile" or "cased drilled pile" technique consists in introducing a metal pile or working casing into the ground, for example by vibro-sinking, until reaching a hard / resistant layer (also known as "bedrock"). resistant "). A borehole (or well) is made within this beaten pile or working casing driven into the ground. For this, it implements a drilling device like trepan emulsifier, comprising a drill head capable of breaking the rocks encountered, under the action of repeated shocks resulting from free falls of a few meters in height.

The borehole is periodically cured, this by an injection of compressed air which raises the rock debris within the drilling device. A partial or total reinforcement is then reported within the beaten pile or working casing, followed by concreting with the dip tube, before extraction of the working casing or with the metal pile in place. Such beaten piles are particularly well suited for river or maritime works, such as river bridge foundations, ducal dolphin foundations and quay foundations. In practice, on some sites, it is necessary to achieve different diameters of piles, and therefore to dig a borehole within different diameters of metal piles or working casings. Now, the current trephine foam devices comprise one-piece drill heads which are each capable of producing a specific diameter of a borehole. Projects of this kind therefore require today to mobilize several emulsifiers which are each able to achieve one of the expected diameters. In view of the foregoing, there is a need for a technical solution that would simplify the execution of a construction site during which different diameters of piles will have to be made. OBJECT OF THE INVENTION To respond to this technical problem, the Applicant has developed a new drilling device of the trepan emulsifier type, adapted to adapt to a range of diameters of metal piles or working casings (especially the most used, to for example, between 508 mm and 1020 mm). The drilling device of the trepan emulsifier type according to the invention thus comprises a tubular structure which comprises (i) an elongate body and (ii) a drill head provided with teeth and fitted to a lower end of the elongate body. The tubular structure defines a conduit that is associated with means for routing the drilling debris from a lower opening at said drill head to an upper opening in said elongated body. And in accordance with the invention, the drill head and the elongate body have complementary structures which are adapted for detachable assembly of said drill head to said elongated body, said drill head and said elongate body being secured together by the through removable securing means. The drilling device according to the invention is thus able to receive an interchangeable drill head, chosen as a function of the diameter of the pile to be constructed.

According to advantageous design features, which can be taken independently or in combination with one another: the drilling head is in the form of a female sleeve in which the lower end of the elongate body is engaged forming a tubular section lower male; in this case, preferably, the sleeve-shaped drill head comprises: - a tubular member in which is fitted, with play, the lower tubular section of the elongate body, and an inner ring which is formed at a level of lower border of said tubular member and which covers the free bottom edge of said lower tubular section of the elongated body; - The complementary structures of the drill head and the lower end of the elongate body comprise bearing surfaces provided with means for indexing / locking in rotation between said drill head and said elongated body; in this frame, preferably, the drill head and the lower end of the elongate body define a longitudinal axis, and the bearing surfaces extend in a plane perpendicular to said longitudinal axis; in addition, the indexing / rotational locking means comprise at least one pair of connection composed of a radial rib and a complementary radial groove, formed for one on said drill head and for the other on said elongate body; the teeth of the drilling head are each carried by a toothed blade which comprises a lower section carried by the drill head and an upper section carried by the elongate body, which upper section of each tooth blade is extended by a wing; radial extending along said elongated body; in this context, preferably, the ends facing the lower section and the upper portion of a toothed blade form the bearing surfaces provided with locking / indexing means; more preferably, the tubular structure comprises four groups each composed of a tooth, a tooth blade and a radial wing, which groups are evenly distributed over the circumference of said tubular structure; the peripheral diameter defined by the drilling head is greater relative to the peripheral diameter of the elongate body, and said elongate body is equipped with means for defining a bulk of which the peripheral diameter is identical, or at least approximately identical, with respect to the diameter peripheral defined by said drill head; preferably, the elongate body comprises radial wings, each of which is equipped with at least one platen attached by means of removable securing means, and said platens together define a peripheral diameter which is identical, or at least approximately identical, relative to at the peripheral diameter defined by the drill head; - Removable securing means between the complementary structures comprise a set of connecting members which are arranged to exert resistance to tensile / compressive forces; preferably, the drill head and the lower end of the elongate body define a longitudinal axis, and the connecting members consist of bolts each reported between a pair of plates which extend perpendicularly to said longitudinal axis, one of which is carried by the drill head and the other of which is carried by the elongated body, said bolts extending parallel to said longitudinal axis; more preferably, each pair of plates extends between two toothed blades; - The means for the path of drilling debris comprise: - means for generating compressed air, and - at least one pipe, an upstream end of which is connected to said means for generating compressed air, and a downstream end of which opens within said conduit and above the drill head. The present invention also relates to a drill head for a drill bit of the trepan emulsifier type as defined above.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT The invention will be further illustrated, without being limited in any way, by the following description of a drilling device, this in relation to the appended figures in which: FIG. 1 is a diagrammatic representation of drilling device according to the invention, during a drilling operation of the type "beaten trefoil pile" or "cased drilled pile"; FIG. 2 is an isolated view of a drilling device according to the invention; FIG. 3 is a partial and enlarged view of the drilling device according to FIG. 2, showing the upper end of its elongated body; FIG. 4 is a partial and enlarged view of the drilling device according to FIG. 2, showing the drill head equipping the lower end of its elongated body; - Figure 5 illustrates the drill head according to Figure 4, here in perspective; - Figure 6 corresponds to the drill head assembly / lower end of the elongate body according to Figure 5, with a partial / local section to illustrate the complementary structures of these two parts; FIG. 7 is an exploded view of the drill head / lower end assembly of the elongate body according to FIG. 5; FIG. 8 is a partial and enlarged view of the drilling device according to FIG. 2, showing a section of its elongated body equipped with plates for centering it within the metal pile or working casing; Fig. 9 is a cross-section of the elongate body shown in Fig. 8, passing through its centering plates; - Figure 10 shows in perspective, with a local section, a second embodiment of a drilling head equipping the lower end of the elongate body. The drilling device 1 of the drill bit type, generally illustrated in FIGS. 1 and 2 and by detailed views in FIGS. 3 to 9, is adapted to the implementation of a so-called "pile" drilling technique. beaten trephined "or" cased drilled pile ".

In particular, the drilling device 1 according to the invention is suitable for drilling in the soil S of a hole (or well), that in a metal pile or a working casing T previously embedded in the soil S (Figure 1). Such a drilling device 1 is interesting in the construction of poles (or piles) of a deep foundation, during river works or maritime for example. "Core drill bit" refers in particular to a drilling device 1 by trepanning which allows (i) a drilling of the hard / resistant layers of the soil S1 (or "resistant substratum") by repeated shocks resulting from free falls of this device 1 and (ii) periodic extraction of the broken material. The drilling device 1 according to the invention, made for example of metal (in particular steel), comprises a tubular structure 2 which comprises (i) an elongate body 3 and (ii) a drilling head 4, equipping a lower end of this elongate body 3 (Figures 1 and 2). The lower end of the elongate body 3 and the drilling head 4 define coaxial longitudinal axes, designated respectively by the 3 'and 4' marks.

The tubular structure 2 defines a duct 21, for the path of the drilling debris (FIGS. 6 and 9), the longitudinal axis of which is coaxial with the longitudinal axes 3 ', 4' of the elongated body 3 and the drilling head 4. This duct 21 comprises two end openings (FIGS. 1 to 7): a lower opening 211 formed at the level of the drill head 4 for the entry of the drilling debris to be evacuated (FIGS. 5, 6 and 7), and - An upper opening 212 formed in the elongate body 3 for the output of the drilling debris to be evacuated (Figure 3). This duct 21 has for example an internal diameter of 290 mm. According to the invention, the drilling head 4 is removably attached to the elongate body 3, so as to constitute an interchangeable drill head 4 which is adaptable to the internal diameter of the metal pile or working casing T to trepanning. For this, as developed below, the drilling head 4 and the elongate body 3 comprise complementary structures 5 which are adapted to the removable assembly of the drill head 4 on the elongate body 3, advantageously by a fitting in translation; and these two assembled elements 3, 4 are fastened together by means of detachable fastening means 6. The elongate body 3 is described in more detail below with reference to FIGS. 3 to 7. The elongate body 3 forming a part principal of the tubular structure 2, comprises a tubular element 31 rectilinear, here constant section having several meters in length, for example 28 meters.

The inner surface of this tubular element 31 here forms the entire length, or almost the entire length, of the conduit 21 for the discharge of drilling debris. The outer surface of this tubular element 31 is provided with radial wings 32, to improve its resistance and to absorb the forces generated by the shocks of the drill head 4. The radial wings 32 each consist of a flat metal plate, comprising - An inner longitudinal edge 321, secured to the tubular element 31 and - an outer longitudinal edge 322 free (Figure 4). The radial wings 32, here four in number, are regularly distributed over the circumference of the elongate body 3. These radial wings 32 extend approximately over the entire length of the elongate body 3 and they stop near a lower end 33 of the elongate body 3. The lower end 33 of the elongated body 3 here consists of a lower male tubular section (visible in FIGS. 6 and 7), without radial wings 32, forming part of the complementary structures 5 for the removable reception of the drill head 4.

The upper end 34 of the elongated body 3 consists of a bent section to guide the discharge of the debris removed. The drill head 4 is illustrated in Figures 4 to 7. This interchangeable drill bit 4 is here in the form of a female sleeve in which the lower tubular section 33 of the elongate body 3 fits together for their assembly. According to FIGS. 6 and 7 in particular, the drilling head 4 comprises in this case: a tubular member 41 in which the bottom tubular section 33 of the elongated body 3 is fitted with clearance, an inner ring 42 which is arranged at a lower end edge 411 of the tubular member 41 and which covers the bottom free edge 331 of the lower tubular section 33 of the tubular body 3, and - several teeth 43 which are each carried by a tooth blade 7 arranged in the extension of one of the radial wings 32.

The tubular member 41 of the drill head 4 forms another part of the complementary structures 5 for the removable assembly with the elongate body 3. The internal diameter and the length of this tubular member 41 thus advantageously correspond, with the clearance, to the outer diameter and the length of the lower tubular section 33 of the elongated body 3. The inner ring 42 serves to reinforce the resistance of the teeth-carrying blades 7. This inner ring 42 has an inner circular edge 421 delimiting the lower opening 211 of the conduit 21. The diameter of this inner circular edge 421 is here identical, or at least approximately identical to the inner diameter of the tubular member 31 of the elongated body 3. The teeth 43 are adapted to break the rock.

The toothed blades 7 are designed to withstand compressive forces. These tooth-holder blades 7 each extend in the extension of the end of one of the radial wings 32 of the elongate body 3. These tooth-holder blades 7 are part of the complementary structures 5 for assembly between the drill head 4 and the lower end 33 of the elongate body 3, intervening here for locking in rotation between these two elements 3, 4 assembled. In this respect, the tooth-holder blades 7 here each comprise a lower section 71 carried by the drill head 4 and an upper section 72 carried by the elongated body 3. The lower section 71 extends over the entire length. of the tubular member 41 of the drill head 4. This lower section 71 comprises - a lower surface 711, covering the inner ring 42 and carrying one of the teeth 43 of the drill head 4 and - an upper surface 712 forming a bearing surface with a complementary surface of the upper section 72. The upper section 72 comprises - a lower surface 721 forming a bearing surface with the upper surface 712 of the lower section 71 and - an upper surface 722 connected by welding with a lower end of a radial wing 32.

The bearing surfaces 712, 721 opposite here extend in a plane P which is perpendicular to the longitudinal axes 3 ', 4' above (Figure 4). These bearing surfaces 712, 721 are designed to withstand the compressive forces.

These bearing surfaces 712, 721 comprise a connection torque 8, forming locking means in rotation between the drill head 4 and the elongate body 3. This connection torque 8 here comprises: a radial rib 81, formed on the bearing surface 712 of the lower section 71, and a complementary radial groove 82 formed on the bearing surface 721 of the upper section 72. The removable securing means 6 are arranged so as to withstand axial tensile stresses ( parallel to the longitudinal axes 3 ', 4') exerted between the drill head 4 and the elongate body 3 assembled by interlocking in translation. In this regard, the removable fastening means 6 here comprise several pairs 61 of plates 611, 612. The plates 611, 612 of each pair 61 are fixed together removably by bolts 62. For this, for each pair, the one of the plates 611 is carried by the drill head 4 and the other of the plates 612 is carried by the elongate body 3. These plates 611, 612, in a crown section, each extend in a plane arranged perpendicular to the longitudinal axis 3 ', 4' of the elongated body 3 and the drilling head 4. Each plate 611, 612 extends in particular between two sections 71, 72 of two toothed blades 7 juxtaposed laterally. The plates 611, 612 facing each other are secured here together by a pair of bolts 62. Each bolt 62 (and in particular their screw) extends parallel to the longitudinal axes 3 ', 4' above, so as to optimize the resistance to the forces traction.

The drilling head 4 further comprises a set of reinforcing plates 9, in crown section, each extending in a plane perpendicular to its longitudinal axis 4 'and the side of the teeth 43. Each reinforcing plate 9 extends in particular between two lower sections 71 of two tooth-holder blades 7 juxtaposed laterally. For optimum interchangeability of the drill head 4, the peripheral diameter d 1 defined by this drill head 4 (and in particular by the outer rim of its teeth 43) is advantageously equal to or greater than the peripheral diameter d 2 of the elongated body 3 (corresponding in particular to the peripheral edge 322 of its radial wings 32) (Figure 4). In this context, for optimum translational guidance in the metal pile or working casing T, the elongate body 3 is advantageously equipped with means 35 for defining a space of which the peripheral diameter d3 is identical, or at least approximately identical, with respect to at the peripheral diameter d1 of the drilling head 4. For this purpose, the radial wings 32 are each equipped with at least one set of removable plates 35 which is attached by means of removable securing means 36, for example bolts ( Figures 1, 2, 7 and 8).

The elongate body 3 comprises a plurality of plates 35, distributed over its length and each reported in a plane at right angles to the longitudinal axis 3 'of the elongated body 3. Each plate 35 consists of a plate of which one of the faces is pressed against one of the faces of the associated radial flange 32. Each plate 35 extends in a plane parallel to the plane of the associated radial wing 32. Each plate 35 also has a lower end and an upper end, both cutaway (or chamfered), in particular to facilitate the insertion and extraction movements through the upper opening of the metal pile or the working casing T. The plates 35 are reported so that their outer peripheral edges 351 extend parallel and at a same distance from the longitudinal axis 3 ', with a longitudinal band 352 projecting so that their peripheral edges 351 extend in parallel. and at a distance from the outer longitudinal edge 322 of the associated radial wings 32. And for each set of plates 35, the plates 35, and in particular their respective outer peripheral edges 351, are arranged so as to define together a virtual cylinder whose peripheral diameter d3 is identical, or at least approximately identical, with respect to the diameter The drilling device 1 also comprises means 10 for the path of the drilling debris from the lower opening 211 to the upper opening 212 of the conduit 21. path 10 consist in this case (Figure 1): - means 101 to generate compressed air, and - pipes 102, here two in number, running along the elongated body 3 for the delivery of compressed air on the side of the lower opening 211 of the duct 21. In particular, each duct 102 has two ends: - an upstream end 1021 connected to the means 101 to generate the ir compressed (Figure 1) and - a downstream end 1022 (Figure 6), opening into the conduit 21, above the drill head 4 and the lower end 33 of the elongate body 3, between two upper sections 72 For an optimal action of the compressed air, a seal is made between the drill head 4 and the lower end 33 of the elongate body 3.

This sealing is in particular ensured by the continuity of the lower tubular member to the cut under the drill head 4. The beveled shape of the free bottom edge 331 of the tubular body 3, with the presence of the inner ring 42 positioned between the drill head 4 and the lower end 33 of the elongate body 3, is useful for facilitating assembly. According to the invention, as a function of the diameter of the metal pile or working casing T, it is thus possible to choose the drill head 4 adapted from a range whose peripheral diameters d1 are different from each other.

For example, according to a variant shown in FIG. 10, the drilling head 4 comprises: the tubular member 41 in which the bottom tubular section 33 of the elongated body 3, the inner ring 42 is formed at the lower edge of the tubular member 41, and - several teeth 43 which are each carried by a toothed blade 7. This drill bit 4 differs from that illustrated in Figures 1 to 9 by a diameter outside dl which is greater than the outer diameter dl of the drill head 4 according to Figure 4. For this, the teeth 43 are of increased radial width. In addition, the lower section 71 of each tooth-carrying blade 7 has meanwhile an increasing radial width, of the trapezoidal type longitudinally, from its upper surface 712 (whose section is identical to the lower surface 721 of the upper section 72) until at its lower surface 711 (identical to the surface of the associated tooth 43). The plates 35 are chosen so as to define together the peripheral diameter d3 which is identical, or at least approximately identical, with respect to the new peripheral diameter d1 of the drill head 4. In practice, a drill head 4 is chosen from a range of heads available (at least two) so that its diameter dl corresponds, with play, to the inside diameter of the metal pile or working casing T.

For example, the drill heads 4 have diameters d1 of between 500 mm and 1000 mm, and in particular of 530 mm, 630 mm, 680 mm, 730 mm, 830 mm and 940 mm. The selected drill head 4 is suitably mounted on the lower end 33 of the elongate body 3, by a translational maneuver in a direction parallel to their longitudinal axes 3 ', 4'. During this fitting, the drill head 4 is suitably angularly oriented so as to produce the pairs of bearing surfaces 712, 721 of the tooth-holder blades 7. This angular arrangement also forms the connection torques 8 ensuring the angular locking: the radial rib 81 of a lower section 71 is housed in the radial groove 82 complementary to an upper section 72. The assembly is finalized by the establishment of the removable fastening means 6, namely the bolts 62 between two plates 61 next to it. Similarly, plates 35 are chosen and implanted on the elongate body 3, to define the diameter d3 corresponding to the diameter of the drill head 4. At the site, the metal pile or the working casing T is driven by vibro-sinking or by threshing in the loose upper layer S2 of the soil S (Figure 1). When this metal pile or working casing T reaches the surface of a resistant layer 51, the drilling device 1 comes into action. For this purpose, this drilling device 1 is raised and released in free fall several times within the metal pile or working casing T, so as to progressively break the resistant layer 51. The vertical drop of the drilling device 1 is guided. by the complementary diameters between, on the one hand, the inner surface of the metal pile or working casing T and, on the other hand, the drilling head 4 and the plates 35. The hole is periodically cured by injection of compressed air which raises the rock debris within the conduit 21 of the drilling device 1. Each drilling phase is alternated with a new phase of driving of the metal pile or working casing T, to obtain an optimal depression of this metal pile or working tubing T in the resistant layer 51. A partial or total reinforcement is then reported within the metal pile or working casing T, followed by concreting to the dip tube. As the case may be: - the working casing T can then be extracted; - The metal pile T is in turn left in place to form the final foundation. For drilling of different diameter on the site, it is sufficient to deactivate the removable fastening means 6, then extract the drill head 4 relative to the lower end 33 of the elongate body 3 by a translational movement parallel to their longitudinal axes 3 ', 4'. The new drilling head 4, having a suitable peripheral diameter, is reported as described above in association with a suitable set of plates 35. In general, the drilling device according to the invention, with its interchangeable drill head, significantly limits the material resources to be mobilized on a construction site. In addition, this drilling device according to the invention combines, in a single tool, trepanation and emulsion functions of the material, and this for a range of diameters.

Claims (12)

1. A drilling device of the trepan emulsifier type comprising a tubular structure (2) which comprises (i) an elongate body (3) and (ii) a drilling head (4) provided with teeth (43) and equipping a lower end (33) of said elongate body (3), which tubular structure (2) defines a conduit (21) which is associated with means (10) for a drilling debris path from a lower opening (211) at the from said boring head (4) to an upper opening (212) in said elongated body (3), characterized in that said boring head (4) and said elongate body (3) comprise complementary structures (5). ) which are adapted to the detachable assembly of said boring head (4) on said elongated body (3), and in that said boring head (4) and said elongate body (3) are secured together through removable securing means (6). 2.- drilling device of the drill bit type emulsifier according to claim 1, characterized in that the drill head (4) is in the form of a female sleeve in which fits the lower end (33) of the body elongated member (3) forming a male lower tubular section. 3.- drilling device bit trefoil type according to claim 2, characterized in that the drill head (4) in the form of a sleeve comprises: - a tubular member (41) in which is fitted, with play, the section tubular body (3), and an inner ring (42) which is formed at a lower edge (411) of said tubular member (41) and which covers the free bottom edge (331) of said tubular body (3). lower tubular section (33) of the tubular body (3). 4.- drill bit of the drill bit type emulsifier according to any one of claims 1 to 3, characterized in that the complementary structures (5) of the drill head (4) and the lower end (33) of the body elongate member (3) comprises bearing surfaces (712, 721) provided with means (8) for locking in rotation between said boring head (4) and said elongated body (3). 5.- drill bit of the trepan emulsifier type according to claim 4, characterized in that the drill head (4) and the lower end (33) of the elongated body (3) define a longitudinal axis (3 ', 4) in that the bearing surfaces (712, 721) extend in a plane (P) perpendicular to said longitudinal axis (3 ', 4'), and in that the rotational locking means (8) comprise at least one at least one connecting torque consisting of a radial rib (81) and a complementary radial groove (82) formed for one on said drill head (4) and for the other on said elongated body (3) . 6.- drill bit of the trepan emulsifier type according to any one of claims 1 to 5, characterized in that the teeth (43) of the drill head (4) are each carried by a tooth plate (7) which comprises a lower section (71) carried by the drilling head (4) and an upper section (72) carried by the elongated body (3), which upper section (72) of each tooth-carrying blade (7) is extended by a radial wing (32) extending along said elongated body (3). 7.- drill bit of the trepan emulsifier type according to claim 6, in combination with any one of claims 4 or 5, characterized in that the ends (712, 721) facing the lower section (71) and the section upper (72) of a toothed blade (7) form the bearing surfaces provided with locking means in rotation (8). 8.- drill bit of the trepan emulsifier type according to any one of claims 1 to 7, characterized in that the peripheral diameter (dl) defined by the drill head (4) is greater than the peripheral diameter (d2) of the elongate body (3), and in that said elongated body (3) is equipped with means (35) for defining a space in which the peripheral diameter (d3) is identical, or at least approximately identical, with respect to the peripheral diameter ( dl) defined by said drilling head (4). 9.- drill bit of the trepan emulsifier type according to claim 8, characterized in that the elongated body (3) comprises radial wings (32) which are each equipped with at least one plate (35) reported through removable securing means (36), and in that said plates (35) together define a peripheral diameter (d3) which is identical to, or at least approximately identical to, the peripheral diameter (d1) defined by the drill head (4). ). 10.- drilling device bit trefoil type according to any one of claims 1 to 9, characterized in that the removable fastening means (6) between the complementary structures (5) comprise a set of connecting members (62). ) which are arranged to exert resistance to tensile stresses. 11.- drill bit of the trepan emulsifier type according to claim 10, characterized in that the drill head (4) and the lower end (33) of the elongate body (3) define a longitudinal axis (3 ', 4' ), in that the connecting members (62) consist of bolts each reported between a pair of plates (61) which extend perpendicularly to said longitudinal axis (3 ', 4'), one of which (611) is carried by the drilling head (4) and the other (612) being carried by the elongate body (3), and in that the bolts (62) extend parallel to said longitudinal axes (3 ', 4') . 12.- Drill head for a drill bit of the trepan emulsifier type according to any one of claims 1 to 11.