Classifications

• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/18—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels
  • E02F3/188—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels with the axis being horizontal and transverse to the direction of travel
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
  • E02D17/00—Excavations; Bordering of excavations; Making embankments
  • E02D17/13—Foundation slots or slits; Implements for making these slots or slits
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/18—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels
  • E02F3/20—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels with tools that only loosen the material, i.e. mill-type wheels
  • E02F3/205—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels with tools that only loosen the material, i.e. mill-type wheels with a pair of digging wheels, e.g. slotting machines
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/18—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels
  • E02F3/22—Component parts

Definitions

• the subject of the present invention is a drilling device using a milling cutter for digging trenches in the ground and in particular in soils having a high hardness.
• FIG. 1 there is shown in elevational view the drilling apparatus described in the document mentioned above. It comprises a main frame 10 which is suspended from the end of a block 12 itself passing over a lifting mast.
• the main frame 10 has two vertical main faces, only the front face 14 being visible.
• the apparatus also comprises a drilling assembly 16 movable in vertical translation at the lower end of the main chassis 10.
• This drilling assembly 16 essentially comprises a support structure 18 on which is mounted a pump 20 for resuming the flow of liquid d drive of the drilled cuttings, this pump 20 being connected to a flexible discharge pipe 22.
• the drilling assembly also comprises two rotary cutters 24 and 26 secured to drums driven by hydraulic motors fixed on the support assembly 18.
• L support 18 can be moved relative to the main frame 10 by means of jacks 28 and 30 which allow on the one hand the relative movement of the drilling assembly 18 relative to the main chassis 10 and on the other hand to apply to the drilling assembly an additional force when the main chassis 10 is anchored in the trench in progress drilling.
• the main frame 10 has two pads, only the pad 30 being visible. These pads can be moved away from the chassis using for example jacks in order to anchor the main chassis in the trench.
• An object of the present invention is to provide a drilling device of the rotary cutter type which effectively makes it possible to drill a trench even in very hard soil and in particular in the case where the soil has a significant transition zone between relatively soil furniture and very hard floor.
• the apparatus for drilling trenches in the ground comprising a chassis, a drilling assembly comprising a horizontal support plate connected to the lower end of the chassis, said plate supporting drilling tools arranged under said plate, said trench being filled with drilling mud
• said plate comprises at its periphery elastic sealing means for cooperating with the walls of the trench in order to achieve at least partial sealing between said plate and the walls of the trench and means for adjusting flow rates of drilling mud from the part of the trench disposed above said plate towards the part of the trench below said plate and in the opposite direction, such so that the pressure of the drilling mud below said plate is much lower than the hydrostatic pressure exerted by the column of drilling mud in the trench above said plate, and that the flow of drilling mud extracted from the portion of the trench below said plate is sufficient to allow the extraction of ground debris resulting from drilling by said drilling tools.
• At least a partial seal is made at the level of the plate between the upper part of the trench filled with mud and the lower part of the trench during drilling thanks to the presence of the elements of sealing at the periphery of the plate.
• the drilling mud flow control system in one direction and in the other with respect to said plate, it is possible to control the pressure of the drilling mud in the part of the trench disposed below this plate. .
• This pressure can thus be kept at a relatively low value of the order of atmospheric pressure. Consequently, the hydrostatic pressure created by the column of drilling mud in the part of the trench above the plate will effectively apply to the drilling tools the equivalent of a force corresponding to the height of drilling mud.
• the drilling apparatus comprises a chassis having two vertical main faces and the drilling assembly is movable vertically relative to the chassis under the effect of jacks interposed between the drilling assembly and the chassis and it is characterized in that it further comprises a plurality of deformable elements integral with said main faces of the upper chassis, and means for injecting a pressurized fluid into said inflatable elements whereby said inflatable elements apply a force between said main chassis and the walls of the trench and means for allowing the exit of said pressurized fluid from said inflatable elements whereby no force is transmitted between said main frame and the walls of the trench.
• FIG. 1 already described, shows a drilling apparatus using cutters of known type
• FIG. 2 is a simplified elevational view of a first embodiment of the drilling apparatus according to the invention.
• Figure 3 is a detail view of Figure 2 showing a first embodiment of the seal between the plate and the wall of the trench;
• Figure 4 is a view similar to that of Figure 3 showing a second embodiment of the seal
• FIG. 5a and 5b show in side view and in front view an improved embodiment of the drilling rig according to the invention
• - Figures 6a and 6b show a first embodiment of the inflatable elements of the embodiment of the apparatus according to Figures 5a and 5b;
• Figures 7a and 7b show a second embodiment of the inflatable elements of the embodiment of the device according to Figures 5a and 5b.
• the principle of the invention consists in using the hydrostatic pressure resulting from the column of drilling mud in the trench extending above the plate of the drilling assembly to increase the apparent weight of the tool and thus improve the efficiency of the drilling tools.
• At least partial sealing is carried out between the plate and the wall of the trench using sealing means arranged at the periphery of the plate and a flow of drilling mud is organized in one direction and in the other through the plate by controlling these flow rates so that the pressure of the drilling mud below the plate is much lower than the hydrostatic pressure, for example of the order of atmospheric pressure and that, in addition, this flow is sufficient to allow the extraction of debris resulting from the drilling carried out by the drilling tools.
• FIG. 2 we will describe a first embodiment of the drilling rig.
• the recovery pump 20 is associated with a suction nozzle 40, the openings of which are arranged below the plate 18. This suction nozzle takes up the drilling mud with the cuttings.
• the trench 42 is shown, the upper part 42a of which has already been drilled and the lower part 42b of which is being drilled.
• the lower plate 18 is equipped on its periphery with a seal 44 providing the seal between the plate 18 and the wall of the trench 42.
• the plate 18 is also crossed in the particular example considered by two pipes 46 and 48 which communicate the upper part of the trench 42a with its lower part 42b. These pipes are equipped with non-return systems and means for controlling the flow 46 'and 48' which pass through them. It is understood that in this way, it is possible to adjust the overall flow of drilling mud entering and leaving the lower zone 42b of the trench and thus adjust the pressure in this zone to a value for example of the order of atmospheric pressure. Adjusting the flow rate of the suction pump allows at the same time to take into account the leakage flow which exists in the area of the sealing means. However, it goes without saying that the flow must be sufficient to ensure the extraction of the cuttings dug by the cutters 24 and 26.
• FIG 3 there is shown a first embodiment of the seal between the plate 18 and the wall of the trench 42.
• the plate 48 is provided on its periphery with a vertical flange 50.
• a deformable rubber seal 52 In the outer face 50a of this rim is anchored a deformable rubber seal 52.
• the seal 52 made of rubber may preferably be hollow to conform more effectively to the unevenness of the wall of the trench.
• FIG. 4 shows a second embodiment of the seal between the plate 18 and the wall of the trench 42.
• the periphery of the plate 18 is also equipped with a vertical rim 54 which forms the entire periphery of the plaque.
• On this rim 54 is fixed an elastic lip seal 56 which also goes all around the plate 18.
• the lip seal 56 is oriented so that the effect of pressing the end of the seal on the wall of the trench is increased by the column of mud disposed above the plate 18.
• lifting bars such as 58 movable relative to the plate 18 and making it possible to cause the separation of the free end of the seal 56 relative to the wall of the trench 42.
• the increase in the apparent weight of the drilling rig is obtained by the combination of the action of hydrostatic pressure as already described in relation to FIGS. 2 to 4 with the action of jacks on the drilling assembly which is then made movable relative to the upper main frame of the drilling rig, this upper chassis being anchored, that is to say immobilized in a vertical direction relative to the trench.
• the anchoring means consist of inflatable elements such as airbags which are arranged on the main faces of the upper chassis of the drilling rig and which, in their inflated state, allow the transmission of a force between the upper part of the chassis and the walls opposite the trench during digging.
• FIGS. 5a and 5b show the main chassis 14 of the apparatus and the drilling assembly 16 with its plate 18 the drilling assembly 16 which can be moved relative to the main chassis 10 by the jacks 28, 30 .
• each inflatable element 64 is constituted by an inflatable cushion limited by a wall made of a tight and elastically deformable material.
• Each deformable cushion is fixed by one of its faces 64a to the main face 60 or 62 of the main chassis and is connected to an individual inflation tube 66 itself connected to a main inflation tube 68.
• These tubes can include adjustable limiters pressure to control the value of the anchoring force.
• FIGS. 5a and 5b in order not to overload them, the provisions shown in FIGS. 2, 3 and 4 have not been repeated, which allow the hydrostatic pressure to act as has already been explained.
• the flow control means 20, 40, 46 'and 48' are mounted on the plate 18 of the movable part.
• the sealing means 44, 52 and 56 can also be mounted on the periphery of the plate 18 of the movable part. It is also possible to provide a seal at the lower end of the main part of the chassis of the machine below the airbags 64, and a seal between the fixed part of the chassis and the movable lower part bearing the strawberries. In both cases the hydrostatic pressure acts on the upper face of the movable part by adding to the force applied by the jacks 28 and 30.
• each airbag 64 is covered by a strip 70 in one reinforced rubber element with edges 70a and 70b are anchored in the wall 60 of the upper chassis.
• one of the walls 72 of the trench during drilling is also shown. It is understood that, when a pressurized fluid, preferably a liquid, is injected into the inflatable elements 64 through the pipes 66 and 68, the inflatable element increases in volume and presses the strip of rubber material 70 against the wall 72. The pressure prevailing in the inflatable element 64 develops against the wall 72 of the trench a force of horizontal component F which is converted into a vertical anchoring force F.
• a pressurized fluid preferably a liquid
• the strip 70 is moved away from the internal wall 72 of the trench and the drilling rig can be moved to drill a new section trench.
• FIGS. 7a and 7b we will describe a second embodiment of the anchoring means.
• These consist of inflatable elements 64 consisting, for example, of airbags identical to those shown in FIGS. 7a and 7b. These cushions 64 are fixed by one of their faces to the wall 60, 62 of the main chassis and connected to the pipes of pressurized fluid.
• a rigid plate 76 covering the entire surface occupied by the inflatable elements 64 is made integral with the wall 60 by an articulated mechanical element 78.
• the mechanical element 78 which consists for example of a connecting rod or more precisely a plurality of connecting rods is disposed above the upper airbag 64a.
• the rigid plate 76 is applied with pressure against the wall 72 of the trench. This makes it possible to obtain a high anchoring force while inducing in the wall of the trench a limited pressure due to the fact that it is the plate 76, which has a large surface, which is applied continuously to the wall of the trench.

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• Engineering & Computer Science (AREA)
• Mining & Mineral Resources (AREA)
• Civil Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structural Engineering (AREA)
• Mechanical Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Paleontology (AREA)
• Earth Drilling (AREA)

Applications Claiming Priority (3)

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• 2000
  • 2000-03-13 FR FR0003155A patent/FR2806111B1/fr not_active Expired - Fee Related
• 2001
  • 2001-03-06 WO PCT/FR2001/000653 patent/WO2001068991A1/fr not_active Ceased
  • 2001-03-06 US US10/221,439 patent/US6839989B2/en not_active Expired - Fee Related
  • 2001-03-06 EP EP01913931A patent/EP1264049A1/de not_active Withdrawn
  • 2001-03-06 CA CA002403182A patent/CA2403182A1/en not_active Abandoned
  • 2001-03-12 JP JP2001069009A patent/JP2001279709A/ja active Pending

Non-Patent Citations (1)

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