EP0825326B1 - Method and apparatus for horizontal drilling and for handling drill rods - Google Patents

Abstract

Drilling long horizontal boreholes below ground produces long horizontal bores (1) in the ground, from an initial subsurface point of desired depth. Here the drive (9) turns a string of drilling rods, making axial (3), horizontal progress in a given direction. The vertical shaft is of constant cross section. Rods (6) to be joined to, or removed from the drill string (7) are lowered to a horizontal position corresponding with the drilling axis, connection or detachment taking place in the shaft, on this axis. Also claimed is the corresponding equipment to drive the horizontal bore. This includes a derrick and rods shorter than its open internal cross section.

Description

I. Field of application

The invention relates essentially to a device for creating a horizontal borehole from a starting shaft without the Having to dig up the ground.

II. Technical background

Each residential and commercial building is underground via a variety of cables laid and disposed of, be it with water, gas or electrical current Etc.

In the past, trenches were used to lay such cables in the ground excavated, the lines laid in it and the trenches again filled. In the open area are the follow-up costs for the restoration of the Soil surface for this is relatively small. If, on the other hand, this happens in a Perform a village with paved roads, paved sidewalks and the like the cost of restoring the surface of the soil increases drastically, making this conventional method of Cable routing especially.

For this reason, it is already known to lay lines without a trench to dig up the entire length of the line.

With a drill, a drill pipe is made up of a large number one after the other, usually screwed together, several each Meters long, composed of boring bars, flat from the ground surface drilled diagonally into the ground. The direction of the drilling progress, i.e. the am front end of the drill pipe existing drill head, can be relative well controlled so that the bore is initially flat obliquely downwards is performed until the required target depth is reached, and then essentially is drilled horizontally, again under the control of the In the desired direction.

The pipeline to be installed is brought into the borehole in that after completing the hole and before pulling back the drill pipe pipe to be pulled in, usually a somewhat flexible steel or plastic pipe, using a special device at the front end of the drill pipe attached and thus the gradual retraction of the drill pipe laying pipe is drawn into the existing borehole.

Here, the drill pipe is from one at the rear end on Drilled drill pipe pushed forward and additionally in the Usually the drill pipe is driven in rotation and / or through the exit of Water under high pressure from the drill head that in front of the drill head Material washed out, mostly through a hollow through hole in the Drill pipe.

This method is mainly used for laying cables over larger ones Distances, for example 100 m or several hundred meters, used so that the one that cannot be used for a line that must be routed in depth Initial distance on which the hole only reaches its target depth, one represents reasonable effort. In addition, the drilling rig used for this which, among other things, has a slant pointing downwards to guide the Must have drill pipe, large and at least two tons heavy, because the weight of the drill partly as a bearing for the force to Presses the drill pipe forward.

However, there is a special problem when connecting buildings:

The main line of a supply line, which mostly runs under the street, for example a gas, water or power line, is intended to cross one of them branching house connection line of one of the buildings standing on the street tap.

It is still common today to pass these house connection lines through Excavation of a trench to be laid conventionally, since at the ends of this House connection line, namely at the connection point with the main line of the Supply line on the one hand and at the breakthrough through the basement wall of the House, on the other hand, space and accessibility for manual work anyway must be present, and most of the trench to be excavated anyway only over the plot of land that is usually still under construction Building runs so that no large surface work is required. Indeed the finished road surface is destroyed over part of the trench and must then be carefully repaired again, whereby especially when tarring this will never be like the original condition on a paved road.

It would therefore be desirable to also use this and similar applications To have methods or an apparatus available, which in the Soil surface z. B. in the area of the paved or paved road only one minimally small hole required, and not a trench along its entire length the line to be laid, e.g. B. the house connection line.

The previously known drilling method with the penetration of the hole flat obliquely in the underground is just for the creation of House connection lines are not suitable for various reasons:

With the known method, the bore can be controlled relatively precisely be, but it is not possible, on the one hand, with the hole to be drilled drill as close as possible to the main line to be connected, without not at the same time take the risk of damaging this line when drilling.

In addition, the drilling of the hole in the subsurface would have to be done on a from the main line relatively far laterally offset position. The Setting up the drill would either be on the opposite Take place on the street side and thus block a complete street side, or - there the resulting cross distance is usually not sufficient is likely - in the property opposite in the house to be connected. This would mean that with a z. B. 2 t heavy drill in a garden plot would have to drive in. The resulting Destruction and restoration work already leave for cost reasons discard this method, although in practice this does not include the necessary approval from the property owner would be obtained.

In addition, it is already known from US 4,630,967 and from GB 2 276 895 by a vertical starting shaft from the borehole directly to the desired depth and direction to start from one placed in the vertical launch shaft Derrick.

The drill pipe is attached to the rear end of the drill pipe The drill pipe in the start shaft is extended, and thereby the drilling forward driven.

For this purpose GB 2 276 895 A1 shows a magazine in which the individual Boring bars are accommodated one above the other in two parallel belts and by means of the straps each individual boring bar at the level of the drilling axis lowered and can be picked up by the drill drive.

In US 4,630,967, the individual boring bars are made from an above-ground one Magazine lowered individually onto the drilling axis by means of a crane and from the drilling drive added.

However, the latter does not allow complete automation of the drilling operation including boring bar change. But above all, the drill drive used as changer drive in a second function.

III. Presentation of the invention a) Technical task

It is therefore the object according to the invention, a method and a To provide apparatus for such substantially horizontal holes and cables to be laid therein with the least possible damage to the surface, especially only a relatively small opening in the floor surface, preferably in the area of the connection between the main branch and the branch Cable to be able to manufacture and the boring bar change independent of the method of boring and realized automatically can.

b) solving the problem

This object is achieved by the characterizing features of claim 1 solved. Advantageous embodiments result from the subclaims.

By inserting a vertical starting shaft in the area of the main line to be connected, two problems are solved simultaneously:

On the one hand, space is created here for those who have relocated House connection line manual connection of main line and Service line. The starting shaft is either conventional excavated, or using a special method Rinsing driven vertically into the depth, which makes sense because the Starting shaft to a little below the main line to be connected must extend. When mechanically lifting the starting shaft with Excavator shovel etc. can easily damage this main strand, or it has to be laborious and slow by hand from a certain depth be excavated.

This is in view of a cross section of the starting shaft on the surface and also in the ground of approx. 70 x 40 cm in the horizontal, but a depth of 1 m to 1.50 m difficult to achieve.

The second problem to be solved is the immediately adjacent course of the main line to be connected and the main connecting line to be inserted transversely to each other, that is, an attachment of the main connection line directly above or below the main line to connect the two lines Using a suitable T-piece or other adapter in a simple way and To be able to connect with each other without bridging the length.

If from an open starting shaft, through which the main line runs through, the drilling is started, the borehole can immediately only a few millimeters, striving transversely above or below the main line be started, preferably from the main strand opposite side of the starting shaft.

Working from a starting shaft still allows the line in a substantially straight line connecting the branch point from the main line and the end point of the house connection line in the building manufacture. From the starting shaft you can already move in this direction Usually a horizontal direction, the propulsion should be started so that very little directional interference is required during drilling. This makes it possible to use a drill pipe that is relatively rigid.

This in turn enables the drill pipe to be made from very short, To manufacture boring bars to be screwed together:

A single boring bar is only in its central area, i.e. not in the area their front screw connections with the two neighboring boring bars, flexible. The screw connection itself must under no circumstances be free of play as this will result the directional controllability of the entire drill pipe would be destroyed. Because in the area of the backlash-free screw connection even a pipe Drill pipe is much stiffer than in the middle area of the individual Boring bars, the drill pipe is in the area of its screw connections as hardly to look sideways.

Corresponding is a drill pipe, which consists of drill rods composed of those that exist at the start and end area Make up approx. 20-25% of the total length of each boring bar, to be regarded as overall not very elastic in the transverse direction.

Since in the aforementioned case only a very small lateral deflection of the bore is necessary, the drill pipe can therefore consist of very many individual, very short Boring bars are assembled. This enables one Starting shaft, the cross section of which is no greater than that in depth given small cross section in the floor surface, a horizontal Achieve drilling progress with a drill string, the individual Boring bars in the direction of the drilling axis to the rear end of the existing drill pipe can be applied. As a result, the individual Boring bars must be significantly shorter than the length measured in the horizontal the cross section of the starting shaft.

Furthermore, it does not make sense to work from such a starting shaft to advance the hole by rinsing with high pressure from Drill head made of water brought into the ground. This water would collect at the back of the drill pipe, i.e. in the starting shaft, and the subsequent work on the connection of the main line and Make house connection line impossible without first all the water pump down etc.

By using a very stable drill pipe, especially by Boring bars made of solid material or at least of very large tubes Wall thickness, it is possible to drill the hole primarily, especially exclusively, by pressing the drill pipe forward. This is especially for Working from a starting shaft is suitable because the drill drive, which the drill pipe must press forward, well on the opposite wall can support the starting shaft.

Rotating the drill string around the soil material in front of the drill head scraping or loosening up makes sense only in exceptional cases. On However, turning the drill pipe by less than 360 ° must be possible because via an asymmetrical bevel at the top of the drill pipe and their angular position with respect to the drilling axis, the direction of the drilling feed is controlled.

By placing the boring bar in the direction of the drilling axis, which in the runs essentially horizontally, it is still possible to make the new Boring bars to be added or removed already in this horizontal position from a storage magazine into the starting shaft bring in or remove. This creates difficulties due to Change of direction of the boring bars during feeding such as jamming etc. largely avoided.

Using a boring bar changer, which has its own changer motor , the boring bars to be added are each on the rear end of the drill pipe screwed on. It is preferably done beforehand with the help of the changer motor and the threaded connector attached to it Shot from the higher boring bar magazine.

The drill drive itself, which - as previously described - primarily or exclusively pressing forward in the direction of the drilling axis is in the starting shaft Can be pushed back and forth parallel to the drilling axis, at least around the length of a single boring bar. The drill drive preferably moves between an advanced position immediately at the beginning of the Drill hole in the starting shaft, and a retracted position in the Close to those arranged on the opposite wall Boring bar changing device is arranged back and forth.

Both the boring bar changer and the boring drive are preferred arranged within a derrick, which consists of a latticework There is metal pipes and preferably on its peripheral walls with plates is covered against falling earth into the starting shaft. This The drilling rig is whole, for example by means of a hand winch, from above lowered into the starting shaft. Since the starting shaft and also the derrick while drilling the hole to below that through the start shaft extending main strand are in the derrick and its walls corresponding on the side of the main line, from below in the derrick open, recesses.

The starting shaft is preferably introduced in such a way that the locking main strand is located under the boring bar changer while the much more space-consuming drill drive between the Main line and the opposite wall of the starting shaft, in which is to be drilled. The housing of the Extend the drill drive to below the lower edge of the main strand.

The boring bar magazine consists of a vertical or inclined slide, in which the boring bars are on top of each other. In the lowest position is the Open on the face to remove the bottom boring bar from the Magazine. The boring bar is in this removal position substantially vertically above the drilling axis, and can therefore be vertical from that Removable boring bar changer opposite the derrick become:

For this purpose, the interchangeable slide, on which the changer motor is located, raised to the level of the removal position on the motor axis of the Changer motor located threaded connector for a predetermined period of time in the boring bar located at the removal position of the boring bar magazine screwed in (with the boring bar passing through the others Boring bars or an additional weight is prevented from turning) and by moving the changer motor with threaded connector along the Changer carriage removed from the magazine in the horizontal direction. To lowering down to the drilling axis is done by turning in the opposite direction and Push the changer motor forward with the boring bar on this boring bar screwed on the rear end of the drill pipe located in the hole. The boring bar magazine preferably ends in the drilling rig below Soil surface, but begins above the soil surface and can also protrude diagonally from the rig of the derrick for one easier loading by hand with additional boring bars.

The drilling rig itself will be operated horizontally within the launch shaft hydraulic clamping cylinders clamped to not only hortizontally, but also vertically the position once defined for the introduction of the Keep hole too.

c) working examples

Fig. 1:

das erfindungsgemäße Bohrgerät in der Seitenansicht,

Fig. 2:

das Gerät gemäß Fig. 1 von vorne in Blickrichtung der Bohrachse, und

Fig. 3:

das Gerät in der Aufsicht von oben.

An embodiment according to the invention is described in more detail below by way of example with reference to the figures. Show it:

Fig. 1:

the drill according to the invention in side view,

Fig. 2:

1 from the front in the direction of view of the drilling axis, and

Fig. 3:

the device from above.

In Figures 1 and 2, Figures 1a and 2a each show the lower, in Starting shaft 2, part of the device located, while Figures 1b and 2b show the upper part which partially protrudes from the floor surface 5.

The elements of the drill are within one made of metal profiles manufactured derrick 11, the outer surfaces preferably - in the drawings are not shown - are covered with metal plates, according to the Lowering the derrick 11 into the starting shaft 2 from falling in To prevent soil material in the derrick 11.

The drilling rig 11 is, for example, not - in the drawings shown - hand winch lowered into the starting shaft 2, and can to this Purpose, for example, in a subframe parked above the starting shaft are guided vertically by guide rollers, slideways etc.

In the lower part of Fig. 1a is the drilling axis 3 and the in the borehole 1 introduced into the left side wall. In this borehole 1 a branch line is later to be pulled in, which crosswise with the through the lower part of the starting shaft 2 main strand 8 one Supply line can be connected using a sleeve, etc.

For this purpose, the borehole 3 and thus the subsequent connecting line runs just above the main line 8 of which two possible different ones Sizes are shown in Fig. 1a. The derrick 11 has in the area of Main strand 8 open recesses in its side walls from below, to be lowered with its lower edge to below the main strand 8 can.

The essential elements of the device according to the invention are all on or housed within derrick 11:

First, the drill drive 9, which the drill pipe to the left in the direction the drilling axis 3 presses forward or when removing the drill pipe the borehole 3 pulls back the drill string 6, which continues vertically extending drill rod changer 12, which is located in the borehole 3 Drill pipe 6 by attaching additional drill rods 7 to the latter gradually extending the rear end or when pulling back the drill pipe 6 gradually shortened and the boring bar magazine 19, in which the am Drill rods 6 to be attached boring bars 7 or the Inclined slide 24 into which those removed from the drill pipe 6 Drop boring bars and laterally out of derrick 7 above the Slip out floor surface 5 to be cleaned there by the operating personnel Damage checked and greased for reuse.

For reasons of clarity, there is no one on the drilling axis 3 in FIGS. 1 and 2 Drawn drill pipe, but in Fig. 3. It can be seen that the Drill rods 6 made of one behind the other screwed boring bars 7, like one of them in Fig. 1a, screwed onto the threaded connector 34 of the changer motor 13.

Each threaded rod 7 has an annular groove 18 on its outer circumference.

As can be seen in Fig. 1a, the boring bar changer 12 moves in essentially vertically above the main strand 8. The means of Boring bar changer 12 transported boring bar 7d moves within a substantially vertical transport path 10. The drill drive 9 is on the drilling axis 3 along guides 29 with the aid of hydraulic pistons 30 slidable. For pressing the drill pipe 6 forward and thus for Driving the bore forward, the drill drive 9 grips the rearmost, still in Area of the derrick 11 positioned drill rod 7 of the drill string 6, and the entire drill drive 9 is beyond the position shown in Fig. 1a shifted to the left. The drill drive 9 thus moves between the in Fig. 1a left wall of the starting shaft 2 and the main line 8, which near the opposite shaft wall is arranged back and forth.

In addition to an axial movement in the direction of the drilling axis 3, the drilling drive 9 can also rotate the drill pipe additionally, both during the Linear movement or separately. For this purpose it is the drill pipe holding rotary jaw 33 of the drill drive 9 relative to its housing 35 coaxial to the drilling axis 3 rotatable or pivotable. This serves the Direction control in conjunction with one at the top of the Drill pipe asymmetrically arranged slope.

Furthermore, the drilling drive has one arranged in front of the rotary jaw 33 Breakaway jaw 32, which rotates the drill string relative to the Housing 35 of the drill drive can hold.

Another jaw 21 is in the immediate vicinity of borehole 3 with respect to the drill pipe 6 fixedly arranged on the derrick 11. This too Clamping jaw 21 consists - as can be seen better from FIG. 2a - of two across individual jaws directed against the drill pipe, each, or together by means of a hydraulic cylinder 21 ', which has one end is fixedly mounted in relation to the derrick 11, operated.

At the lower end of the drilling rig 11, still below the drilling drive 9 and of the main strand 8 are 3 extending in the direction of the drilling axis Clamping cylinders 22a, 22b fixedly arranged on the derrick 11, which at the free end their piston rod have a press plate 25. Because in this area the Drilling rig 11 has no external cladding, is by extending the emergency as a rule hydraulically operated piston rods of these clamping cylinders 22 the press plates 25 pressed against the wall of the starting shaft 2 and thus the derrick 11 against the opposite wall of the starting shaft 2. So that the entire derrick 11 is fixed in the start shaft 2, which for the Alignment of those defined by the drill drive 9 with respect to the derrick 11 Drilling axis 3 compared to the started borehole 1 is important.

On the opposite side of the drill drive 9 in the starting shaft 2 is the Boring bar changer 12 arranged above the main strand 8. The Boring bar changer 12 consists essentially of one Changer motor 13 with a threaded connector 34, which is preferably directly on the Output shaft of the changer motor 13 is arranged. This threaded connector 13 is equipped with a suitable thread to attach to the rear End face of the boring bars 7 arranged threads for connecting the individual To be able to screw boring bars together. As in Fig. 1a can be seen, it is preferably a along a conical surface applied external thread on the boring bar 7, preferably a Round thread shape is used to prevent damage as much as possible avoid. Accordingly, the threaded connector 34 has a contrary to this Internal thread, and the changer motor 13 is with its axis of rotation oriented parallel to the drilling axis 3 of the drilling drive 9. The changer motor 13 can be both vertically in the direction of the drilling axis 3 and transversely thereto along the derrick 11:

For this purpose, the changer motor 13 is attached to a motor frame 16. The motor frame 16 is by means of rollers 36, the one on its outer circumference Have an annular groove, along two preferably vertically spaced preferably round bars as motor frame guides 17 along the drilling axis 3 movable. The motor frame guides 17 are in turn on one Changer 14 attached, which is preferably formed by means of analog Rollers 39 in the vertical direction along rod-shaped slide guides 15 is movable, which is spaced in the direction of the drilling axis 3 in the drilling rig 11, in the vicinity of the end face opposite the drilling drive 9, are arranged.

The changer motor 13 can be moved vertically with the help of the changer carriage 14 Direction so that it is with its axis of rotation in the lowest Position aligned with the drilling axis 3, and in its uppermost position - as on best seen in Fig. 2b - with one in the upper area of the derrick 11th arranged gripper 23, which in turn by means of - preferably twice acting - hydraulic cylinder 23 'is actuated. Between these two End positions, preferably still below the level of the floor surface 5, in any case above the drilling axis 3, is on the path of movement of the Changer motor 13 the removal position of a magazine 19 for new, on Drill rods 6 bores 7a, 7b, 7c to be attached. This magazine 19 consists essentially of a hollow profile-like enclosure 20, which is oblique is arranged rising up to a maximum vertical, and into which the boring bars 7 be filled in from above.

At its lower end, the enclosure 20 has a stop for the bottom Boring bar 7a and the enclosure 20 is on the changer motor 13th facing end face of the bottom boring bar 7a open.

The magazine 19 preferably projects above the level of the Soil surface 5 and extends or laterally from the derrick 11 out to be easier to fill with boring bars 7 by the operating personnel can.

If the changer motor 13 is aligned with the in the removal position in Magazine 19 recorded boring bar 7a, the changer motor 13 by longitudinal movement along its axis of rotation and simultaneous Rotation of the threaded connector 34 are screwed onto the boring bar 7a. This is prevented from rotating due to the weight of the boring bars lying above it and, if necessary, an additional one in magazine 19 stored weight 42. By reversing the changer motor 13 together with the boring bar 7a along the axis of rotation of the Changer motor 13, the boring bar 7a is removed from the magazine 19 and can be added to the drill pipe 6.

Above the lower end of the magazine 19 is in the vertical path of movement the boring bars transported by means of the boring bar changer 12 below of the gripper 23 an inclined slide 24 arranged so that its high End is still below the gripper 23. One using the boring bar changer 12 upwards into the gripper 23 bored rod 7 presses the Inclined slide 24, which is about a pivot axis from this path of movement can be folded out to the side. Then the inclined slide 24 tilts due to gravity back into the functional position shown in Fig. 2b. In In this functional position, boring bars 7k held by the gripper 23 initially fall after releasing into the inclined slide 24 and rolling along this Inclined slide laterally out of the derrick 11, where it from Operating personnel for cleaning and further processing be accepted.

The function of the device according to the invention is described below with reference to Figures described.

It is assumed that the well has already started drilling and will continue to be advanced.

In this case, the changer slide 14 of the boring bar changer 12 follows above for removing a new boring bar 7a from the magazine 19 is the motor frame 16 with the changer motor 13 in the horizontal on furthest away from the borehole, i.e. on the right edge of the Starting shaft 2 in Fig. 1a.

The changer slide 14 is up along the guides 15 driven until the threaded connector 34, which with the changer motor 13th is rotationally coupled, with the thread of the lowest, in the removal position of the Magazine 19 located, boring bar 7a is aligned. Then the threaded connector 34 on its axis of rotation to the left, i.e. forward, against it Boring bar 7a driven and driven by the changer motor 13 so that the threaded connector 34 is screwed to the boring bar 7a. This It is screwed on by a timer which is connected to the changer motor 13 is limited to a certain period of a few seconds.

To grip the threads of the threaded connector 34 and the boring bar 7a allow, there must be pressure in the axial direction. To this end the threaded connector 34 is moved axially horizontally with the changer motor 13, by the motor frame 16 relative to the changer slide 14 in the direction of Drilling axis 3 is moved along the motor frame guides 17a, 17b. This happens with the help of a hydraulic piston attached to the changer slide 14 37, which moves the motor frame 16 horizontally.

Since the extension and retraction of this hydraulic piston 37 is not so precisely controllable is how it defines the axial progress when screwing in a thread Speed corresponds to, is between the hydraulic piston 37 and thereby moved motor frame 16 at least one spring 38, preferably for both Movement directions each have a spring 38a, 38b interposed to here to ensure the necessary length compensation in the direction of the drilling axis 3.

To continue misalignment between the axis of rotation of the Threaded connector 34 and the boring bar 7a located in the magazine to compensate, the threaded connector 34 is preferably fixed on the output shaft the - hydraulic or electric - changer motor 13 arranged, this Changer motor 13, however, not arranged fixedly with respect to the motor frame 16, but movable with the help of rubber bearings, whereby the axis of rotation of the Changer motor 13 compared to the motor frame 16 both a light Cross offset as well as an angle change can take place.

The compensation functions described are not only for removing one Boring bar from magazine 19, but above all for attaching or Removing a boring bar on the drilling axis on or from the drill pipe 6 necessary.

The motor frame 16 is then opposite the changer slide 14 again move back in the direction of the drilling axis 3, whereby the boring bar 7a, which now sits on the threaded connector 34, removed from the magazine 19 becomes. By moving the changer slide 14 vertically along the Guides 15 this boring bar 7a - that in Fig. 1a in this transport position is drawn as boring bar 7d - move down to the drilling axis Third

By moving the motor frame 16 forward relative to the changer slide 14 in Fig. 1a to the left, the front end 27 of this boring bar with the back end of the last boring bar one already in the borehole located drill pipe 6 - as shown in Fig. 3 - brought into contact. The simultaneous rotation of the changer motor 13 makes this new Screw the boring bar onto the drill pipe at the rear and drill pipe 6 thereby extended.

The screwing is carried out until one with the changer motor 13th coupled torque sensor a sufficiently strong torque when Screwing reports. The previous one is during screwing Boring bar of the drill pipe 6 by means of the rotary jaw 33 of the drilling drive 9, which is in a relatively advanced position to the left located, non-rotatably clamped.

After the end of the rotation of the changer motor 13, this rotary jaw 33 loosened and the drill drive 9 - see Fig. 1a and Fig. 3 - along to the right retract its two guides 29 so far that the rotary jaw 33 in Area of the last newly installed boring bar 7 is, and from the rotary jaw 33 can be clamped to the threaded connector 34 of the Boring bar changer 12 by rotating the changer motor 13 backwards to release the newly attached boring bar 7.

During this loosening of the jaw 33 and retracting the Drill drive 9, the drill string 6 in the previous position, both axially also with respect to the rotational position - with respect to the borehole 1 by the Clamping jaw 21 fastened the drill pipe close to the borehole on drilling rig 11 6 is stuck. When unscrewing the threaded connector 34, the motor frame 16 compared to the changer slide 14 again horizontally by means of the Move hydraulic piston 37 to the rear.

Now - after loosening the jaw 21 - by moving the entire drill drive 9, the drill string 6 by the length of the new one Boring bar 7 are pressed forward by using the entire drill drive 9 its hydraulic pistons 30, preferably arranged on both sides, opposite the Drilling rig 11 is pushed forward along its guides 29, which with a Force of about 2 t happens. The drill pipe is used for directional control before pressing forward or at the same time under certain circumstances using the The rotary jaw 33 of the drill drive 9 is rotated somewhat about the drill axis 3. In front, during or after pushing the drill drive 9 the whole Move boring bar changer 12 up again to the next one Get boring bar 7 from the magazine 19. Through the multiple repetition this process, the drill pipe 6 is expanded to the desired length and thus drove borehole 1 to the target point in a controlled manner.

In particular if the drill string 6 from the drill drive 9 is only by means of Non-positive connection for the axial movement as well as for the rotary movement is held, it may happen that the drill string 6 compared to the jaw 33 of the drill drive 9, or also against the attached to the derrick 11 jaw 21 slips.

To notice this, and then the target position between Drill drive 9 and the drill pipe 6 can be taken again on Drill drive 9, preferably on its housing 35, at least one sensor 28, however, preferably three sensors 28a, 28b, 28c are arranged. This Sensors 28, preferably designed as inductive sensors, provide the axial Relative position to the boring bar 7 located in the area of the drill drive 9, in that one sensor 28a reacts when the annular groove 18 of this boring bar 7 is exactly opposite. If the drill pipe 6 in the direction of the drill axis 3 slips relative to the drill drive 9, the annular groove 18 leaves the area of this sensor 28a, and this emits an error signal.

Since the other two are adjacent on both sides in the direction of the drilling axis 3 Sensors 28b, 28c are arranged, the annular groove 18 must be one of the two Sensors 28b, 28c have overflowed, which has a corresponding signal has produced. As a result, the direction of displacement of the drill string 6 known to the drill drive 9 and - preferably after fixing the Drill pipe 6 in the borehole 1 by means of the fixed on the derrick Clamping jaw 21 - the drilling drive 9 is again in the direction of the drilling axis 3 move that the sensor 28a is opposite the annular groove 18, that is, the target position is taken again.

Removing the drill pipe 6 from the borehole 1 by pulling it back - usually at the same time the desired line by attaching to front end of the drill string 6 is drawn into the hole 1 - how follows before:

First of all, a wiper (not shown) is usually present on the drill drive 9 from one or more rubber lips or a rubber grommet, provided to roughly clean the drill pipe 6 withdrawn from the borehole 1.

At the start of the retraction process, the jaw 33 of the drill drive 9 holds the rearmost drill rod of the drill pipe 6, the drill drive 9 in the position advanced against borehole 1 on the left edge of the Starting shaft 1 in Fig. 1a, is located.

From this position, the drill drive 9 is moved to the right by the length of one The boring bar 7 is withdrawn, then the drill pipe 6 is fixed in the borehole 1. by the clamping jaw 21 arranged on the drilling tower 11 which is next to last or a boring bar of the drill pipe 6 lying further forward is fixed.

Then the penultimate boring bar of the drill pipe 6 from the breakaway jaw 32 clamped. Then the threaded connector 34 - with this design together with the changer motor 13 - in alignment with the drilling axis 3 brought and then on the rear end of the Screwed drill pipe 6 by the threaded connector 34 forward, so in usually clockwise, rotated and at the same time by the above Move forward toward the back end until one is sufficient fixed screw connection between the threaded connector 34 des Boring bar changer 12 and the last boring bar 6 is given what especially by torque monitoring when screwing on is checked. Now the rotary jaw 33 is about ½ about the drilling axis 3 Turn to the left, i.e. in the opening direction of the thread, whereby the threaded connection between the last and the penultimate boring bar of the drill pipe 6 is broken.

Now the rotary jaw 33 of the drill drive 9 releases this last drill rod 7 and drives forward against borehole 1 to the now last boring bar of the To seize drill pipe 6 and again as far out of the borehole withdraw that they are removed from the drill string 6 as previously described can. At the same time or subsequently, the broken screw connection through the threaded connector 34 and changer motor 13 together with that on it originally located last threaded rod by turning the thread in Reverse direction (turning to the left) and at the same time in the process of Boring bar changer to the rear, away from the drill pipe, completely loosened. Before or at the same time, the one located on the threaded connector 34 Boring bar by raising the changer slide 14 and possibly simultaneous left-hand movement of the motor frame 16 compared to the Changer carriage 14 - in the gripping area of the gripper 23 in the upper area of the Drilling rig 11 brought. For this purpose, the magazine 19 from the vertical movement path of the boring bar can be taken out by Pull up or fold away the magazine 19 in relation to the derrick 11. Furthermore, the boring bar transported in this way presses before reaching the gripper 23 the pivoted inclined slide 24 out of its path of movement to the side.

After closing the gripper 23 with the help of its piston 23 ' Boring bar 7k as shown in Fig. 2b held by the gripper 23, and the Threaded connector 34 can by rotating the changer motor 13 and simultaneous backward movement of the motor frame 16 compared to the Carriage 14 to be solved.

By opening the gripper 23 this boring bar 7k falls into the meantime the force of gravity in the inclined chute 24 which has fallen back in FIG. 2b and rolls along this inclined slide laterally out of derrick 11 for the further Treatment by the operating personnel.

Simultaneously or subsequently, the boring bar changer 12 moves downwards Procedure for removing the next boring bar from the drill pipe 6.

Claims (11)

1. Apparatus for producing a long, substantially horizontal bore-hole from a preset starting point situated at a depth, having a drilling drive (9) and a drill string (6) comprising a plurality of drilling rods (7), wherein

   the apparatus comprises a drilling tower (11) of which at least part can be lowered into a vertical starting pit (2) in the ground,

   the individual drilling rods (7a, 7b, 7c) for the drill string (6) are shorter than the greater, longitudinal dimension of the free horizontal cross-section (4') inside the drilling tower (11),

   the apparatus has a drilling-rod changer (12),

   characterised in that

   the drilling-rod changer (12) comprises a changer motor (13) which is arranged in a fixed position on a motor frame (16), the motor frame (16) being displaceable on motor-frame guides (17), along the substantially horizontal drilling axis (3), relative to a changer slide (14), and

   the changer slide (14) is displaceable on substantially vertical slide guides (15) relative to the drilling tower (11) to enable it to move the changer motor (13) to and fro between the drilling axis (3) and a magazine (19) for drilling rods (7).
2. Apparatus according to claim 1, characterised in that the drilling rods (7a, 7b, 7c) each have, in the same axial position, depressions projecting radially inwards from the outer circumference, and in particular a circumferential annular groove (18).
3. Apparatus according to either of the foregoing apparatus claims, characterised in that

   the drilling drive (9) comprises a sensor (28) for checking the desired position of the drilling rod (7) held by the drilling drive, and thus of the drill string (6), relative to the drilling drive (9) in the axial direction, and

   the sensors (28) respond to the recesses or annular groove (18) in the drilling rod (7).
4. Apparatus according to one of the foregoing apparatus claims, characterised in that the changer motor (13) is hydraulically driven.
5. Apparatus according to one of the foregoing apparatus claims, characterised in that the motor frame (16), together with the changer motor (13), is displaceable relative to the changer slide (14) by means of at least one hydraulic piston (37), the hydraulic piston (37) engaging with the motor frame (16) by means of at least one spring (38) arranged there between as a length compensator.
6. Apparatus according to claim 5, characterised in that, in the transverse direction, the motor-frame guides (17) for the displacement of the motor frame (16) relative to the changer slide (14) are arranged on one side, at a considerable spacing from the drilling axis (3).
7. Apparatus according to one of the foregoing apparatus claims, characterised in that the changer motor (13) has a timed switching device for the fitting or detaching of an additional drilling rod (7) to or from the drill string (6).
8. Apparatus according to one of the foregoing apparatus claims, characterised in that a clamping jaw (21) for fixing the drill string (6) in the axial direction is arranged in a fixed position on the drilling tower (11) directly against the bore-hole (1).
9. Apparatus according to one of the foregoing apparatus claims, characterised in that the drilling tower (11) has, preferably below the drilling axis (3), at least one clamping cylinder (22) which extends in the direction of the drilling axis (3), by which the drilling tower (11) can be clamped in place in the starting pit (2).
10. Apparatus according to one of the foregoing apparatus claims, characterised in that there is arranged in the region of the drilling-rod changer, at the top end of the displacement travel of the latter's changer slide (14), a holding unit, particularly in the form of a downwardly open gripper (23), to hold the drilling rod (7) while the threaded connector (34) of the changer motor (13) is being unscrewed, to allow the drilling rod (7) to be put aside after it has been removed.
11. Apparatus according to claim 10, characterised in that the gripper (23) is arranged above a pivotable inclined chute (24), which chute (24) can be pivoted about an axis in such a way that a drilling rod (7) which is brought up from below by means of the drilling rod changer (12) is able to pivot the chute (24) out of the path of movement of the said drilling rod (7) between the drilling axis (3) and the gripper (23) arranged there above.

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