EP1448866B1 - Method and device for boring holes - Google Patents

Description

The present invention relates to a method for drilling, in particular impact or rotary impact drilling, of Holes in soil or rock material, where by a drill bit supported on a drill pipe by a hammering and / or rotating motion a borehole is formed and a cladding tube is inserted into the wellbore is degraded, with at least one supply port degraded Material and / or in particular through the drill pipe in the area of the drill bit introduced rinsing or cooling fluid in one between the outer circumference of the drill string and introduced into the inner circumference of the cladding tube defined annular space and discharged from the wellbore. The invention further relates to a device for drilling, in particular impact or rotary impact drilling, from holes in Soil or rock material, one on a drill string mounted drill bit by a beating and / or rotating motion forms a borehole and a drill pipe surrounding jacket or cladding tube in the borehole einbringbar, in particular through the interior of the Bohrgestänges a rinsing or cooling fluid in the field of Removal surface of the drill bit can be brought in and mined material and / or the rinsing or cooling fluid over at least one Feed opening in an annulus between the drill pipe and the cladding tube einbringbar and ausbringbar from the borehole is.

Methods and devices of the type mentioned are for example from AT-B 390 303, WO 98/21439 or WO 00/57019 known, in these known embodiments degraded material and / or introduced flushing or cooling fluid substantially via a between the Drill pipe and the cladding tube defined annulus applied becomes. The flushing or cooling fluid may be in the range the excavation surface of the drill bit, for example via a corresponding cavity introduced in the interior of the drill string become. A disadvantage of these known embodiments is in particular the fact that at a water entry when performing the drilling, where appropriate the water enters the borehole under high pressure, this incoming water together with the mined material as well as the introduced rinsing or cooling fluid in particular through the annulus between the drill string and the cladding tube as well as along the outer circumference of the cladding tube is discharged from the well and thus a hazard representing for the operator, wherein due to a prevailing, high pressure, if necessary also the entire drilling device against the drilling direction can be discharged from the borehole.

The present invention aims to provide a method and a device of the type mentioned above further, that upon entry of water, if necessary under high pressure, in the borehole and especially in the Ensured area of the drill bit a seal to this effect can be that the leakage of water in particular about the available during the normal drilling process stationary transport cross sections for mined material and rinsing or cooling fluid is prevented and a safe Anchoring the drilling device or at least the Jacket or cladding tube is achieved.

To solve these problems, the method of the beginning mentioned type essentially characterized in that at or after completion of the well, the supply of Flushing or cooling fluid is interrupted in the drill bit, that the feed opening for the introduction of mined material and / or rinsing or cooling fluid in the annular space between interrupted the drill pipe and the cladding tube, in particular is sealed fluid-tight and that the jacket or cladding tube at its projecting from the borehole end set the borehole wall and against this fluid-tight is sealed. Due to the fact that according to the invention both the Supply of flushing or cooling fluid interrupted in the drill bit is as well as the access or supply opening in the Annular space between the drill string and the cladding tube interrupted or is sealed fluid-tight, it is ensured that upon entry of water into the wellbore, in particular in the area of the drill bit, this if necessary high pressure water is not contrary to Supply direction for the flushing or cooling fluid and in the Abtransportrichtung for the mined material and the introduced Rinsing or cooling fluid discharged from the wellbore will, so that a corresponding threat to the operator as well as damage outside of Boreholes located additional devices prevented becomes. In addition, the invention provides that the jacket or cladding tube at its protruding from the borehole Fixed end against the borehole wall and fluid-tight is sealed, so that also a leakage of water over the between the outer circumference of the cladding tube and the Boreholeinnenwand free space safely avoided becomes. It is thus provided according to the invention that in the area the drill bit a reliable seal the annulus between the drill string and the cladding tube, which during the drilling process for a removal of the mined Material is used, achievable and simultaneously leakage of water over the outer circumference of the cladding tube is also prevented. It also ensures that not contrary to the feed pressure for the rinsing or cooling fluid optionally water via the supply line drilled out of the drill hole in the drill pipe and in corresponding feeders outside the borehole is introduced.

According to a preferred embodiment it is proposed that provided in the jacket tube supply opening for an introduction of material in the annulus between the drill pipe and the cladding tube by moving the drill bit against the direction of drilling over at least one of the the excavation surface of the drill bit facing away end provided Sealing is sealed. Such a shift the drill bit against the drilling direction can be precautionary be made with achieved, desired borehole length, to an eventual subsequent occurrence of water into the borehole and exit of the same safely to be able to avoid. If while drilling the Borehole penetrated into material or rock layers is contained in which water, especially under high pressure is, takes place contrary to the introduction of force for implementation the drilling process, a displacement of the drill bit against the drilling direction, so that automatically a corresponding Sealing the feed opening in the interior or Annular space between the drill string and the cladding achievable is. Moreover provided by the invention Interrupting the supply of flushing or cooling fluid through the drill pipe as well as the anchoring and sealing of the cladding tube on its outer circumference at the from the Drill hole projecting end is thus essentially automatic or automatically at water inlet under a corresponding Pressure achieved a seal of the borehole.

To further secure at least the cladding tube in the borehole is proposed according to a further preferred embodiment, that the cladding tube in the region of the seal on the from the borehole projecting end to prevent a Secured distance from borehole counter to drilling direction, in particular wedged or jammed. at Occurrence of high fluid pressures arise with appropriate Cross sectional area of the drill bit, if necessary high forces, which in the sense of leakage of the drilling elements become effective from the well, so that in addition to the invention intended fixing and sealing of the from the borehole protruding end of the cladding tube an additional Securing, in particular by wedging or jamming the respective Hüllrohrendes is proposed.

To at least parts of the bore for the implementation used elements and reuse if necessary according to a further preferred embodiment suggested that the drill string after completion the bore in a conventional manner of the Drill bit is separated and discharged from the cladding tube becomes. In such a way can be essentially the drill pipe reuse over the entire length while the drill bit together with the cladding the sealing of the borehole against leakage of water from the wellbore provides.

For an appropriate backup of after removing the Drill string in the borehole remaining cladding as well the drill bit is according to a further preferred embodiment suggested that after removing the drill pipe in a conventional manner, the borehole, in particular the jacket or cladding tube, with a hardening material is filled.

To solve the above objects is a device of the type mentioned above essentially characterized that in the supply line for the flushing or cooling fluid into the drill bit as well as in the area of at least a feed opening in the annulus between the drill string and at least one sealing element is provided to the cladding tube is and that the cladding on the borehole projecting end to the surrounding soil or rock material via a fixing and / or sealing device set and sealed fluid-tight. According to the invention It is thus proposed that both the supply line for a supply of the flushing or cooling fluid into the drill bit as also the supply opening for the removal of dismantled Material and introduced rinsing or cooling fluid accordingly is interrupted and sealed to a withdrawal optionally water entering at high pressure over the drill bit as well as during the drilling process to prevent transport cross-section provided. In addition, an appropriate determination and / or sealing device for fixing and sealing provided the projecting from the borehole end of the cladding tube.

For a particularly simple and essentially self-acting or automatic interruption of the detergent supply as well as sealing the supply line for the flushing fluid is proposed according to a preferred embodiment, that in the supply line for the flushing or cooling fluid to the Bohrkrone a contrary to the feed direction of the rinsing or Cooling fluid closing check valve is provided.

Such a check valve can be correspondingly easy and cost, especially in the field of drill bit immediately before the exit of the flushing fluid from corresponding Through openings in the mining area of the Arrange drill bit and results in the event that in the area the mining area entering water a higher Should have pressure as the supply pressure of the flushing fluid, immediately an automatic interruption and sealing the supply line for the flushing fluid.

For a particularly reliable sealing of at least an access or feed opening in the annulus between the drill pipe and the cladding tube during the drilling process be provided for removal of mined material and introduced rinsing or cooling fluid is according to a further preferred embodiment proposed that the remote from the excavation surface of the drill bit end of the Bohrkrone at least one sealing element is provided, which after completion of the borehole in particular by a movement of the drill bit against the drilling direction the feed opening formed in the cladding tube into the annulus seals between the drill string and the cladding. One Such sealing element can be correspondingly to that of the excavation surface of the drill bit opposite end of the drill bit provide, as already explained above, by a retraction of the drill bit in the cladding tube on completion the bore or possibly a movement of the Drill bit by acting on the mining surface water pressure against the propulsive forces directly and automatically the at least one feed opening in the annulus between interrupted the drill pipe and the cladding tube and is sealed, so that a leakage of water, in particular under high pressure, reliable over this annulus to the outside is prevented.

In this connection, according to a particularly preferred Embodiment proposed that the sealing element at a matched to the inner dimensions of the cladding tube Extension of the drill bit is formed, which with additional Sealing elements, in particular sealing rings formed is. Such an extension is used during the drilling process as a guide for centering the drill bit in the Cladding tube and can be correspondingly accurate in one, if necessary reinforced, received front portion of the cladding to be after a retraction or retraction the drill bit counter to the drilling direction in the cladding tube a reliable sealing of the feed opening in the annulus between the drill string and the cladding tube. The sealing effect can hiebei next to a precise fit arrangement the drill bit or the extension of the drill bit in Cladding by additional provision of sealing elements, in particular seals are supported, which in particular are arranged such that in the closed position the additional sealing elements according to the positioning or formation of the at least one access opening are arranged.

As already mentioned above, especially at high Press large forces depending on the mining area or cross-sectional area of the drill bit on the drill bit and in particular the cladding tube in the sense of expulsion from the Borehole be effective. In addition to the inventively provided Fixing and sealing the projecting from the borehole End of the cladding tube is according to a further preferred Embodiment proposed that at the fixing and / or sealing device for fixing and sealing of the cladding tube at the projecting from the borehole End provided at least one securing or clamping element is. Such a securing or clamping element allows a substantially unhindered introduction of the Cladding during the drilling process, during an application or force in the sense of expulsion of the cladding tube from the borehole counter to the drilling direction an additional clamping force and thus supporting power is provided for fixing the cladding tube.

A special reliable and easy to manufacture additional protection of the cladding can be hiebei thereby achieve that the securing or clamping element of a ring element surrounding the cladding tube is formed, which on its outer surface a conically tapering Has surface and with a complementary, conical tapered inner surface of the fixing element at a movement of the cladding tube cooperates counter to the direction of drilling and a movement of the cladding tube against the Drilling direction prevents, as a further preferred Embodiment of the device according to the invention corresponds.

For at least partial recovery or reuse of Elements of the drilling device according to the invention is according to a further preferred embodiment, that the drill pipe from the drill bit in per se known Is releasable and removable from the borehole.

Fig. 1 einen schematischen Schnitt durch eine erfindungsgemäße Vorrichtung zur Durchführung des erfindungsgemäßen Verfahrens während des Bohrvorgangs; und

Fig. 2 in einer zu Fig. 1 ähnlichen Darstellung die erfindungsgemäße Vorrichtung in einem Zustand, in welchem eine Abdichtung der Bohrvorrichtung einen Austritt von Fluid unter hohem Druck aus der Bohrvorrichtung sicher verhindert.

The invention will be explained in more detail with reference to an embodiment schematically illustrated in the accompanying drawings. In this show:

1 shows a schematic section through an inventive device for carrying out the method according to the invention during the drilling process. and

Fig. 2 in a similar to Fig. 1 representation of the device according to the invention in a state in which a seal of the drilling device reliably prevents leakage of fluid under high pressure from the drilling device.

With the device shown in Figs. 1 and 2 is by a drill bit 1, which is mounted on a drill pipe 2 is made a hole 3, the drill bit 1 at its excavation surface 4, for example, corresponding hard material or carbide inserts 5 has. About the Drill pipe 2 is via a schematically indicated supply line 6 a rinsing or cooling fluid in the area of the mining area 4 of the drill bit 1 is introduced, wherein in Figs. 1 and 2, an outlet opening 7 is indicated. In the supply line 6 is in the field of drill bit 1 a check valve 8, which is opposite to the 9 indicated Supply direction for the flushing or cooling fluid closes.

The drill string 2 is surrounded by a cladding tube 10, wherein degraded material and introduced flushing or cooling fluid according to the arrows 26 via passage or Feed openings 12 in the annular space 13 between the outer periphery the drill string 2 and the inner circumference of the cladding tube 10 introduced and deployed from the borehole 3 becomes, as shown in Fig. 1, which the drilling state shows.

The cladding tube 10 is projecting at its out of the borehole 3 End region 14 via a fixing device 15 on the the borehole 3 surrounding material 16 secured, in addition a sealing element 17 is indicated.

Furthermore, the projecting from the borehole 3 end portion 14th of the cladding tube 10 of a securing element or safety wedge 18 surrounded, this safety wedge 18 a to the end of the cladding tube 10 tapered outer surface 19, which with a correspondingly tapered Inner contour 20 of the fixing element 15 cooperates, so that the drilling process, which also according to Arrow 9 is carried out without hindrance can and also the cladding tube 10 according to the Bohrfortschritt for example, by a Zugmitnahme on the Drill pipe 2 can be introduced into the borehole 3, while a movement of the cladding tube 10 counter to the drilling direction and thus in the sense of a discharge from the borehole 3 both on the fixing and sealing device 15 and 17 and the additional safety device 18 is prevented.

In Fig. 2, the state is shown, in which the drill bit 1 either against the drilling direction 9 in the interior of the cladding tube 10 has been withdrawn or the drill bit 1 for example, by an entry of fluid, in particular Water according to the arrow 21 in the interior of the borehole 3 shifted against the drilling direction in the cladding tube 10 has been. In the position shown in Fig. 2 includes an entry of water under high pressure in the front of Dismantling surface of the drill bit 1 lying space 22 the check valve 8 in the supply line 6 for the rinsing or Cooling fluid.

In addition, the supply openings 12 in the annulus 13 between the drill string 2 and the cladding tube 10 by a sealing member 23 is closed, which on an extension 24 facing away from the excavation surface 4 of the drill bit 1 End is formed, wherein the sealing member 23rd not only according to the exact fit inside the cladding tube 10th is guided, but to further support the sealing effect additional sealing elements 25, in particular sealing rings having. It is thus reliable by the sealing element 23 an entry of material as well as possibly Water under high pressure into the interior of the annular space 13 avoided.

Characterized in that the cladding tube 10 via the fixing device 15, the sealing device 17 and the additional Safety wedge 18 at the projecting from the borehole 3 Safely anchored at the end of 14 and also opposite the surrounding Material 16 is sealed, is thus also at this Expose an escape of water and mined material the borehole 3 safely prevented. In addition, through the fixing device 15 and the securing device 18 reliably ensures that even at high Press, for example, reach some ten bar can, taking into account a corresponding cross-sectional area the drill bit 1 and the weight of optionally a large length drilling elements leakage of boring device elements from the borehole 3 avoided together with the fluid under high pressure can be. It can thereby endanger the operating personnel as well as a possible damage in the Drawing not shown additional equipment in particular for acting on the drill pipe 2 for Implementation or production of the bore can be avoided.

After the state obtained in Fig. 2 of a reliable Sealing of the wellbore 3 with respect to an exit from Water can drill pipe 2 according to the drill bit or the extension 24 is separated with the sealing element and reused for a new drilling operation become. To further secure the finished Bore is below the interior 13 of the cladding 10th filled with a hardening material.

Claims (12)

1. A method for drilling, in particular percussion drilling or rotary percussion drilling, holes (3) in soil or rock material, wherein a drill hole (3) is formed by a drill bit (1) mounted on a drill rod assembly (2) by a percussive and/or rotary movement and an enveloping or jacket tube (10) is introduced into the drill hole (3), wherein excavated material and/or scavenging and/or cooling fluid introduced into the region of the drill bit (1) particularly through the drill rod assembly (2) is introduced into an annular space (13) defined between the external periphery of the drill rod assembly (2) and the internal periphery of the jacket tube (10), and discharged from the drill hole (3) via at least one supply opening, characterized in that, during or upon completion of the drill hole (3), the supply of scavenging and/or cooling fluid into the drill bit (1) is interrupted, that the supply opening (12) for the introduction of excavated material and/or scavenging and/or cooling fluid into the annular space (13) present between the drill rod assembly (2) and the jacket tube (10) is sealed in a fluid-tight manner, and that the enveloping or jacket tube (10) on its end projecting from the drill hole (3) is fixed and sealed relative to the drill hole wall (16) in a fluid-tight manner.
2. A method according to claim 1, characterized in that the supply opening (12) provided in the jacket tube (16) for charging material into the annular space (13) present between the drill rod assembly (2) and the jacket tube (10) by displacing the drill bit (1) in a sense opposite to the drilling direction is sealed by at least one sealing element (8, 23) provided on the end facing away from the excavation surface of the drill bit (1).
3. A method according to claim 1 or 2, characterized in that the jacket tube (10) is secured and, in particular, wedged or clamped in the sealing region on the end projecting from the drill hole (3) so as to prevent its removal from the drill hole (3) in a sense opposite to the drilling direction.
4. A method according to claim 1, 2 or 3, characterized in that the drill rod assembly (2) in a manner known per se is separated from the drill bit (1) and removed from the jacket tube (10) upon completion of the bore.
5. A method according to claim 4, characterized in that, upon removal of the drill rod assembly (2) in a manner known per se, the drill hole (3) and, in particular, the enveloping or jacket tube (10) is filled with a hardening material.
6. A device for drilling, in particular, percussion drilling or rotary percussion drilling holes (3) in soil or rock material, wherein a drill bit (1) mounted on a drill rod assembly (2) makes a drill hole (3) by a percussive and/or rotary movement and an enveloping or jacket tube (10) surrounding the drill rod assembly (2) is capable of being introduced into the drill hole (3), wherein scavenging and/or cooling fluid is capable of being introduced into the region of the excavation surface of the drill bit (1) particularly through the interior of the drill rod assembly (2) and excavated material and/or said scavenging or cooling fluid is capable of being introduced into an annular space (13) provided between the drill rod assembly (2) and the jacket tube (10), and discharged from the drill hole (3), via at least one supply opening (12), characterized in that at least one sealing element (8, 23) is provided in the supply duct (6) for supplying scavenging and/or cooling fluid into the drill bit (1) as well as in the region of the at least one supply opening (12) running into the annular space (13) present between the drill rod assembly (2) and the jacket tube (10), and that the jacket tube (10) on its end (14) projecting from the drill hole (3) is fixed to, and sealed in a fluid-tight manner relative to, the surrounding soil or rock material (16) by a fixing and/or sealing means (15, 17).
7. A device according to claim 6, characterized in that a non-return valve (8) shutting in a sense opposite to the scavenging and/or cooling fluid supply direction (9) is provided in the supply duct (6) intended to supply scavenging and/or cooling fluid to the drill bit (1).
8. A device according to claim 6 or 7, characterized in that at least one sealing element (23) is provided on the drill bit end facing away from the excavation surface (4) of the drill bit (1), which sealing element (23) upon completion of the drill hole (3) will seal the supply opening (12) formed within the jacket tube (10) and opening running into the annular space (13) present between the drill rod assembly (2) and the jacket tube (10), particularly by a movement of the drill bit (1) in a sense opposite to the drilling direction (9).
9. A device according to claim 8, characterized in that the sealing element (23) is formed on a drill bit projection (24) adapted to the internal dimensions of the jacket tube (10) and provided with additional sealing elements (25) and, in particular, sealing rings.
10. A device according to any one of claims 6 to 9, characterized in that at least one securing or clamping element (18) is provided on the fixing and/or sealing means (15, 17) for fixing and sealing the jacket tube (10) on its end (14) projecting from the drill hole (3).
11. A device according to claim 10, characterized in that the securing or clamping element (18) is formed by an annular element surrounding the jacket tube (10), which has a conically tapering surface (19) on its outer face and cooperates with a complementary conically tapering inner face (20) of the fixing element (15) at a movement of the jacket tube (10) in a sense opposite to the drilling direction (9), thus preventing a movement of the jacket tube (10) in a sense opposite to the drilling direction (9).
12. A device according to any one of claims 6 to 11, characterized in that the drill rod assembly (2) is detachable from the drill bit (1) in a manner known per se and removable from the drill hole (3).

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