LU88007A1 - Method and device for processing drilling products - Google Patents

Description

"Method and device for processing drilling products"

The present invention relates to a method for treating drilling products emerging from a well being formed.

The present invention also relates to a device for treating such drilling products.

When drilling, in particular on hard ground, for example using a tool called a "downhole hammer", there is a risk of witnessing a strong release of dust capable of polluting the environment of the site.

FR-A-2 152 710 discloses a process using a bell opening facing the drilling orifice, in which the carrier gas charged with the drilling products is collected and in which it is brought in against running a gas which aims to prevent dust from crossing the top of the bell along the axis of the tool and which then leaves the bell with the drilling products. This known method has the disadvantage of not avoiding pollution of the environment where the collector leaving the bell conducts the dust flow, unless of course providing a dust collector at the exit of the collector, which is expensive. US-A-2,646,256 deals with the case of upward-directed drilling. The dust is removed by a liquid stream and the seal around the tool is ensured by compressed air enclosing a seal. It is necessary to prevent the liquid from leaking along the tool. This process is complex and requires pumping large quantities of liquid, which must then be collected, etc.

The object of the invention is to remedy these drawbacks and in particular to propose a particularly simple and effective method and device for treating the drilling products emerging from the drilling being carried out.

According to a first aspect of the invention, the method for treating drilling products in which a chamber opening facing the drilling opening is used in which the carrier gas loaded with drilling products is collected and in which entering a gas which then leaves the room with the drilling products, is characterized in that the gas which is brought into the room is a gas previously humidified which is put into circulation in the room so that it loads drilling products so that they are weighed down and agglomerated by moisture when they escape from the chamber.

The gas can be air. The humidity which it contains according to the invention agglomerates in particular the finest particles. It is thus possible to collect at the outlet of the chamber the gas loaded with the weighed drilling products in order to reject the assembly at an appropriate site on the site or even in a bucket of an evacuation vehicle. Even at the place where we reject this flow, the environment is not polluted.

According to another aspect of the invention, the device for treating drilling products, comprising a chamber opening facing the drilling orifice, in which the carrier gas charged with drilling products is collected and comprising means for making entering the chamber a gas which then leaves the chamber with the drilling products, is characterized in that it comprises means for previously humidifying the gas which is introduced into the chamber and means for putting this gas into circulation device in the chamber so that it takes charge of the drilling products so that they are weighed down and agglomerated by moisture when they escape from the chamber.

The device rests at the top of the borehole while the drilling instrument slides through it to penetrate deeper and deeper into the ground. The device is thus particularly simple and cooperates with the drilling instrument to define an annular chamber in which the humidified gas undergoes a gyratory movement which is particularly effective for the action of humidity on the dust particles. Other features and advantages of the invention will emerge from the description below, relating to a non-limiting example.

In the accompanying drawings: - Figure 1 is an elevational view of a railway construction wagon carrying a downhole hammer drilling device in the transport position; - Figure 2 is a schematic end view of the same wagon, the downhole hammer device being in the preparatory position for drilling; - Figure 3 is a top view of the wagon with two possible working positions of the drilling device, one in solid lines, the other in phantom; - Figure 4 is an axial sectional view of the downhole hammer equipment equipped with the processing device according to the invention, shown schematically; - Figure 5 is a partial schematic view, on a reduced scale of the equipment and the processing device at the start of drilling in hard soil; - Figure 6 is a view similar to Figure 5 but in the case where an initial auger drilling was carried out in a soft surface layer; FIG. 7 is a view of the drilling of FIG. 6 after a certain working time of the equipment with a downhole hammer; - Figure 8 is an axial sectional view of the processing device; - Figure 9 is a view of the processing device in section along the plane IX-IX of Figure 8, with however partial representation of the flange and the seal located above this plane; - Figures 10 and 11 are detail views, on an enlarged scale, of Figure 9; and - Figure 12 is a view similar to Figure 9 but simplified and showing the flows. The invention will now be described in the example of drilling to be carried out along a railroad track, with a view to installing catenary supports.

For this purpose, a site wagon 1 is used that can be moved on the rails 2 of the railway track to be equipped, and carrying a rotary turret 3 which can be oriented by means of a motor 4, the output shaft of which drives a pinion 6 meshing with a crown 7 secured to the frame 8 of the turret 3. An arrow 9 can pivot around a horizontal axis 11 relative to the frame 8 under the action of a jack 12.

A ramp or slide 13 is articulated to the arrow 9 at a distance from the axis 11 between a horizontal rest position shown in FIG. 1 and a substantially vertical working position shown in FIG. 2, by means of a jack 14. The verticality of the slide 13 in the working position is adjustable by means of the jack 14 and, in the other plane, of a motor 16, in particular to compensate for the possible slope of the rails 2.

As shown in Figure 3, when the ramp 13 is in the vertical working position, the turret 3 has previously been oriented by the motor 4 in one or the other of two working orientations in each of which the arrow 9 extends on one side or the other with respect to the rails 2. The ramp 13 carries in a sliding manner equipment with a downhole hammer 17 which, in the two situations represented in FIG. 3, is located in the axis of the drilling to be carried out.

As shown in FIG. 4, where the ramp 13 is not shown, the downhole hammer equipment 17 comprises a rotary tool 18 carrying carbide buttons 19 at its working end. The tool 18 is fixed to the end of a rotation drive tube 21 itself connected to a rotary drive drive source 22 which is only shown schematically in Figures 1 and 2; and shown schematically by an arrow 22 in Figure 4. In the tube 21 is slidably mounted a hammer 23 (Figure 4) which is actuated back and forth vertically by pneumatic means 24 to repeatedly strike the top of the tool 18. The pneumatic means 24 are supplied by compressed air entering the tube 21 through an orifice 26 formed at the end opposite to the tool 18. The pneumatic means 24 are exhausted through a central duct 27 of the hammer 23 and a central duct 28 of the tool 18, which communicate with each other through the hollow interior of a mutual guide sleeve 29. The air exits through the front end of the tool 18 by distributed orifices 31 communicating with the central duct 28, then ascends (arrows F4) to the ground surface 30 by traveling axially or, due to the rotation of the tube 21, helically along the wall of the tube 21 to orifice 32 of borehole 33 being carried out. The equipment described so far is conventional, the equipment with a downhole hammer being for example of the Mission brand, type SD18, hammer diameter 407 mm, tool size diameter: 610 mm. The dry air injected into the bottom of the borehole 33 through the orifices 31 has a vector air function, that is to say that it collects the drilling products detached from the ground by the tool 18, to entrain them out of the borehole 33 through the annular space remaining between the tube 21 and the periphery of the orifice 32 of the borehole.

In accordance with the invention, a device 34 has been placed around the drilling instrument, constituted in the example by the hammer downhole equipment, for the treatment of drilling products collected by the vector air injected at the bottom. drilling.

The device 34 defines along the periphery of the tube 21 above the orifice 32 of the borehole 33, an annular chamber 36 delimited by an enclosure essentially comprising: - an outer peripheral wall 37 of generally cylindrical shape coaxial with the tube 21; - A lower wall 38 comprising a central inlet orifice 39 of diameter greater than the diameter of the tube 21 so as to leave between the periphery of the orifice 39 and that of the tube 21 an annular inlet slot 41; and - an upper wall 42, opposite to the lower wall 38 and comprising a central orifice 43 provided with an annular seal 44 which in service is supported in a substantially leaktight manner on the periphery of the tube 21 by allowing the latter to rotate and slide freely through the processing device 34.

The device 34 further comprises a cover wall 46 located a short distance above the upper wall 42 and which is also traversed in a sliding and rotary manner by the tube 21 with a small clearance to form a seal of the labyrinth type in the event that the flexible seal 44 is defective. To the cover wall 46 is fixed, for example bolted, a flange 47 by which the device 34 is fixed to the lower end of the ramp 13 as can be seen in FIGS. 1 and 2.

The chamber 36 communicates with the orifice 32 of the borehole via the annular inlet slot 41 and braking means 48 for the heavy particles capable of being ejected from the borehole 33 by the vector air leaving it. this. The braking means essentially comprise a cylindrical sheath 48 coaxial with the tube 21 and having an internal diameter slightly greater than that of the intake orifice 39. Thus, the heavy particles ejected helically from the borehole 33 and which consequently tend to spring obliquely under the effect of their centrifugal force strike the inner face of the sheath 48 or the underside of the wall 38 which forms a partial separation collar between the braking chamber defined by the sheath 48 and the chamber 36. The sheath 48 is an easily replaceable bolted wear part. The same applies to the upper wall 42 of the enclosure.

In service, the free lower edge of the sheath 48 is supported on the ground 30 around the orifice 32 of the borehole and this support, which supports at least in part the weight of the device 34 and of the ramp 13, ensures around the the orifice 32 is sufficiently leaktight for most of the vector air and the drilling products leaving the borehole 33 to pass through the sheath 48 and from there into the chamber 36.

When drilling is to be carried out in soil which is hard to its surface 30, work is started as shown in FIG. 5 by placing the tool 18 and the treatment device 34 on the surface of the soil 30. After a certain working time of the tool 18, the situation is then that shown in FIG. 4.

In other cases, the soil is only hard under a certain layer H (Figure 6) of loose soil. In this case, an initial drilling 49 is carried out by means of an auger (not shown). The work with downhole hammer equipment 17 begins at the surface 51 of the hard layer so that the ramp 13 and the processing device 34 are housed in the initial borehole 49 which is flared in shape due to the consistency piece of furniture of layer H. Thanks to the sheath 48 which is of reduced outer diameter compared to the rest of the device 34, the device 34 can go to rest very deeply in the initial drilling 49, that is to say not far from the surface 51 of the hard layer. From this situation, as shown in Figure 7, the equipment 17 practices in the hard layer drilling 33 which is similar to that described with reference to Figure 4. In this situation with initial drilling 49, we call "orifice 32 "of drilling 33 the upper limit of drilling 33 carried out by the equipment 17.

We will now describe in more detail with reference to FIGS. 8 to 11 the processing device 34.

This comprises supply means for introducing a humidified gas, preferably humidified air, in peripheral circulation into the chamber 36 around the equipment 17. These means comprise a prechamber 52 which is defined all around the chamber 36 between the peripheral wall 37, the walls 38 and 42 extended radially outwards and an envelope 53 of generally cylindrical shape coaxial with the wall 37 and of larger diameter than the latter. As shown in FIG. 9, the wall 53 is traversed by a humidified air supply connection 54 oriented obliquely with respect thereto to give the humidified air an initial speed in the peripheral direction as it enters the pre -bedroom 52.

In addition, the peripheral wall 37 of the chamber 36 comprises, distributed around its periphery, vents 56 in the form of an axial slot. Each opening 56 is partially covered on the side of the chamber 36 by an oblique deflector 57 which has the double function of orienting in the desired peripheral direction the movement of the humidified air entering the chamber 36 coming from the pre-chamber 52 and to protect the gills 56 against fouling by the flow resulting from the gyratory circulation in the chamber 36.

On the side of the supply fitting 54 which is opposite to that towards which the fitting 54, by its inclination, directs the flow entering the pre-chamber 52, it is provided in the pre-room 52 to confirm the orientation given to the flows a partition of partial closure 58 which also has the effect of promoting the establishment in the pre-chamber 52 of an overpressure. The vents 56 are dimensioned as a function of the flow entering through the supply connection 54 so that this overpressure is transformed into kinetic energy when the humidified air enters the chamber 36, so as to create in the chamber 36 a suction effect vector air which has been injected into the bottom of the borehole and the particles which it entails.

The peripheral wall 37 is still crossed by a discharge connector 59 which passes through the pre-chamber 52 without communicating with the latter. The connector 59 is extended towards the inside of the chamber 36 by a deflector 61 placed at the downstream end of the opening of the connector 59 in the wall 37 to fold into the connector 59 at least part of the gyratory flow presenting at the entry of fitting 59. -

As still shown in FIG. 9, the device 34 essentially comprises two half-bodies 62 and 63 of generally semi-cylindrical shape which are connected to each other by quick couplers 64 with centering by fitting a narrowed end piece 66 of each half-body 63 between the walls 37 and 53 of the other half-body.

The half-body 63 comprises two cylindrical liners 67 whose axes are 90 degrees from each other and radial relative to the axis Z of the device.

The liners 67 define windows through which, before assembly, the chamber 36 can communicate with the outside in a sealed manner with respect to the pre-chamber 52.

In service, one of the windows 67 (situated on the right in FIG. 9) is closed by a plug 68 (see also FIG. 11) of corresponding cylindrical shape, which is integral with a plywood 69 fixed against the external face of the 'casing 53 by quick couplers 71.

There is interposed between the plywood 69 and the envelope 53 a seal 72 which also closes an orifice 73 and an axial slot 74 formed through the envelope 53 on either side of the jacket 67 in the peripheral direction. .

As shown in the upper left part of Figure 9 and Figure 10, there are on either side of the other window 67 the orifice 73 and the slot 74 above. However, there has been mounted in this region of the casing 53 not a plywood 69 provided with a plug 68, but a block 76 comprising a plywood 77 to which are welded through the drain connection 59 and the connection d 'feed 54, which fit precisely into the jacket 67 and into the orifice 73 respectively. The partial closure 58 is welded to the inner face of the plywood 77 and enters the pre-chamber 52 through the slot 74. These three elements 59, 54, 58 pass through a gasket 78 which is interposed between the plywood 77 and the casing 53. Quick couplers 79 hold the plywood 77 in abutment against the casing 53 by compression of the gasket 78.

In service, the outlet connector 59 is connected to a flexible pipe leading to a suitable place the flow leaving the chamber 36. The supply connector 54 is connected to a compressed air inlet 81 into which opens as a whistle, downstream of a valve 82, a water inlet 83 itself controlled by a valve 84.

Thanks to the quick couplings 71 of the plywood 69 and 79 of the plywood 77, it is easy to mount, as desired, the block 76 in one or the other of the shirts 67, and the plug 68 in the other of the shirts 67. Thus, as shown in FIG. 3, it is possible to ensure that in each working position on either side of the rails 2, the inlet and outlet pipes (not shown) connected to the fittings 54 and 59 are directed parallel to the rails 2, which minimizes the lateral space requirement of the material necessary to carry out the drilling.

As shown in FIG. 8, the liners 67 extend over only part of the axial height of the pre-chamber 52, so that the gyratory flow in the pre-chamber can pass above and below the liner 67 in which the plug 68 is engaged.

We will now describe the operation of the processing device 34 including a description of the method according to the invention.

At the start, one places oneself in one or the other of the situations represented in FIGS. 5 and 6 at the same time as one puts in action of rotation and percussion the equipment with hammer bottom of hole 17, under the action in particular compressed air not saturated with humidity, injected through the orifice 26 of the equipment 17. Humidified air, that is to say charged air, is sent through the supply connection 54 (FIG. 12). of water droplets in suspension, in the prechamber 52 in which this humidified air circulates according to the arrows F1 in a circumferential direction which is the same as the direction of rotation of the equipment 17 (arrow F2). The humidified air circulating under overpressure in the prechamber 52 escapes through the vents 56 to penetrate, gaining speed in the chamber 36 in which it continues its rotational movement in the same direction according to the arrows F3.

In the chamber 36 also flows the unsaturated vector air loaded with drilling products, which rises along the periphery of the borehole (arrows F4 in FIG. 4), enters the sheath 48-then into the chamber 36 (arrows F5 ) with an initial rotational movement, induced by the rotation of the equipment 17, in the same direction as that of the injected humidified air.

The two flows mix, and the rock particles, in particular the finest of them, get heavier and agglomerate on contact with the humidity provided by the injected humidified air. The mixture of the two streams makes one or more turns in the chamber 36 around the equipment 17. A part of this flow hits the deflector 61 and is returned according to arrow F6 in the evacuation connector 59 from where it is leads to a suitable site on the site, for example very close to the rails 2, or else in a collection container carried for example by another wagon of the convoy to which wagon 1 of Figures 1 to 3 belongs. Even if the flow evacuated by the fitting 59 is deposited in the open air, there is no generation of dust because the finest particles have been agglomerated and weighed down by humidity.

In the example of downhole hammer equipment, the references and dimensions of which have been given above, the flow rate of the humidified air injected can be of the order of 10 cubic meters per minute, resulting in a flow rate of water from 5 to 10 1 / min approximately depending in particular on the hardness of the rock and its natural humidity.

Of course, the invention is not limited to the example described and shown, and numerous modifications can be made to this example without departing from the scope of the invention. The invention can be applied to a wide variety of drilling instruments other than downhole hammer equipment. The invention can be used even if the drilling instrument is not equipped with downhole blowing means. Indeed, by playing on the parameters of the humidified air injection, it is possible to create in the chamber a strong cyclonic suction.

Consideration could be given to using as the humidified gas exhaust gas from a cooled thermal engine in order to condense the humidity and, if necessary, subject to additional humidification.

Claims (23)

1. A method for treating drilling products in which a chamber (36) opening facing the drilling orifice (32) is used in which the carrier gas loaded with drilling products is collected and in which a gas which then leaves the chamber (36) with the drilling products, characterized in that the gas which is introduced into the chamber (36) is a gas previously humidified which is put into circulation in the chamber (36 ) so that it takes charge of the drilling products so that they are weighed down and agglomerated by moisture when they escape from the chamber (36). 2. Method according to claim 1, characterized in that the chamber (36) is defined by an enclosure (37, 38, 42) connected in a substantially sealed manner to the orifice of the borehole (32). 3. Method according to one of claims 1 or 2, characterized in that the chamber (36) is supplied with a pressurized wet gas. 4. Method according to claim 3, characterized in that the wet gas is injected tangentially into the treatment chamber (36) to put it in gyratory circulation and to suck the drilling products coming from the orifice (32) of the drilling (33). 5. Method according to claim 4, characterized in that the enclosure (37, 38, 42) is placed around the drilling instrument (17) and the gas is circulated around the drilling instrument. 6. Method according to claim 5, characterized in that when the drilling instrument (17) is rotary, the gas flow is established in the same direction of rotation (F3) as that (F2) of the drilling instrument . 7. Method according to one of claims 1 to 6 characterized in that the gas is introduced into the chamber (36) from a prechamber (52) in which the gas is given, under a certain overpressure, a movement (Fl) which initiates circulation (F3) in the chamber. 8. Method according to claim 7, characterized in that the gas is introduced into the enclosure by gills (56) distributed along the prechamber (52) and causing the prechamber to communicate with the interior of the chamber (36 ). 9. Method according to one of claims 1 to 6, characterized in that the gas is introduced into the chamber (36) by at least one opening (56) oriented in the desired direction of circulation. 10. Method according to one of claims 1 to 9, characterized in that a carrier gas is blown into the borehole (33) to convey the drilling products from the bottom of the borehole towards the interior of the chamber (36) , and the carrier gas and the humidified gas mixed and loaded with the drilling products are discharged through the outlet (59). 11. Device for treating drilling products comprising a chamber (36) opening facing the drilling orifice (32), in which the carrier gas charged with drilling products is collected and comprising means for entering the chamber (36) a gas which then leaves the chamber (36) with the drilling products; characterized in that it comprises means for previously humidifying the gas which is brought into the chamber (36) and means (52, 54) for putting this gas in peripheral circulation in the chamber (36) so that it takes care of the drilling products so that they are weighed down and agglomerated by moisture when they escape from the chamber (36). 12. Device according to claim 11, characterized in that it comprises means for substantially sealingly connecting the chamber (36) with the periphery of the drilling orifice. 13. Device according to one of claims 11 or 12, characterized in that at least part of the supply means (54) and discharge (59) is grouped in a removable block (76) which can be mounted in at least two different locations (67) of the periphery (37) of the enclosure, the device further comprising a removable plug (68) for the other location (67). 14. Device according to one of claims 11 to 13, characterized in that the supply means comprise a prechamber (52) formed along the periphery of the enclosure, a connector (54) for feeding the prechamber, means (58) for directing the flow in the prechamber in the desired direction (F3) of circulation inside the chamber (36) and a communication (56) between the prechamber (52) and the chamber (36). 15. Device according to claim 14 characterized in that the communication comprises several openings (56) distributed along the periphery of the enclosure defining the chamber. 16. Device according to claim 15, characterized in that the openings (56) are axially elongated slots. 17. Device according to one of claims 14 to 16, characterized in that the communication (56) is provided with deflector means (57) which direct the flow towards the interior of the chamber (36) and protect the communication (56 ) fouling by the flow resulting from circulation in the chamber (36). 18. Device according to one of claims 14 to 17, characterized in that the communication is dimensioned to establish an overpressure in the prechamber (52) and a speed up of the gas as it enters the chamber (36). 19. Device according to one of claims 14 to 18, characterized in that the means for directing the flow in the prechamber (52) comprise an at least partial closure (58) of the prechamber (52) on one side of the connector supply (54), so that the gas entering the prechamber goes to the other side of the fitting (54). 20. Device according to one of claims 14 to 19, characterized in that the prechamber (52) is crossed by two jacketed windows (67) which connect the chamber (36) with the outside and leave part of the section free passage of the prechamber (52) for the gyratory flow in the prechamber, each of these windows being able to receive selectively a discharge connection (59) and a plug (68). 21. Device according to one of claims 19 or 20, characterized in that the first open side (38) of the enclosure is equipped with means (48) for braking heavy particles capable of being ejected from the borehole (33) . 22. Device according to claim 21, characterized in that the braking means comprise a sheath (48) for admission into the chamber (36). 23. Device according to one of claims 21 or 22, characterized in that the braking means comprise a baffle (38, 39).