EP1802844B1 - Method for laying pipes without digging trenches - Google Patents

Abstract

In a method for the trenchless laying of pipes, a drilling operation (5) is firstly carried out by means of controlled heading from a starting point (1) to a finishing point (6). Then the drilling head (3) is disconnected from the heading pipes (4) and the heading pipe run is connected by means of a special connecting pipe to the product pipe run (9), which is prefabricated above ground at the finishing point (6). Subsequently, the heading pipes (4) are drawn back from the drill hole to the starting point (1), the product pipe run (9) simultaneously being drawn into the drill hole.

Description

The present invention relates to a method and thereby usable devices for trenchless laying of pipes in the ground.

Numerous methods and devices have been developed in the past for laying pipes in the ground without trenching, thus crossing sensitive areas on the surface of the terrain for which laying in an open trench was not possible or advisable for technical, ecological, legal or economic reasons. This can e.g. be there the case where the surface in the laying area with heavy construction machinery can not be traveled (eg bogs, waters) or where from an ecological point of view, no planning permission can be granted (eg in nature reserves) or where the use of conventional laying techniques would be too expensive (eg with large laying depths and high groundwater level).

The literature contains extensive works on the already used and proven installation methods (eg Stein, D., Trenchless line construction, 2003 Ernst & Sohn. Publisher for Architecture and Technical Sciences GmbH & Co. KG, Berlin, ISBN 3-433-01778-6 ). Here, a classification of the methods has been based on controllability (controlled / uncontrolled processes), soil treatment (soil erosion / soil removal), cuttings transports (mechanical, hydraulic) as well as the number of working steps (pilot drilling, expansion boring, retraction process). or insertion process) proven. Other distinguishing features are, for example, the basic geometric design of the drilling axis (rectilinear, curved) and the pipe materials to be laid by means of the respective method (eg concrete, PE, cast iron, steel, etc.). In addition, the achievable bore dimensions (length, diameter, volume) are sometimes already suitable to assign certain procedures of the same or another group of procedures.

Special attention should also be paid to the suitability of the methods for specific types of soil (grain size, grain shape, cohesive fractions, strengths, etc.), since most processes can only be used in certain soils and at certain groundwater levels (dry, humid, water saturated) do not work under certain groundwater levels. Furthermore, the methods can also be distinguished according to the location of the start or destination point (shaft, excavation pit, terrain surface).

With regard to the method according to the invention, the state of the art most closely represents the so-called pilot tube drives, microtunnelling (microtunnelling, controlled pipe jacking) and controlled horizontal drilling technology (horizontal directional drilling, HDD).

In the pilot tube drives, the installation is carried out in two or three working phases, whereby initially a controlled pilot bore with a relatively small diameter is created and in a further step, this pilot bore is widened to the final diameter and at the same time the product tubes are inserted or retracted. The transfer takes place from a start shaft to a target shaft.

The achievable with these methods bore lengths are generally less than 100 m and the diameter of the pipes to be laid approximately between 100 mm - 1,000 mm. The bore (and thus the pipe installation) is usually rectilinear, ie the control of the pilot hole has the sole Purpose of as straight as possible pipe laying (eg for free fall lines). Due to the process, the pipe strands are successively assembled during the passage of the hole or during installation from individual pipes (jacking pipes, possibly interim pipes or temporarily inserted pipes, product pipes). Another feature of these methods is that these methods are relatively sensitive to certain soil properties (displaceability, water level etc.), so that they are not suitable for example for laying a longer, large-diameter steel pipeline or in rocky soil.

In microtunneling (MT), a controlled, sometimes curved hole is usually created from a launch shaft or a launch pit to a target shaft or a target pit. Characteristic of this method is that pilot drilling, Aufweitbohrung and insertion process of the tubes are realized in a single step. This combined operation is basically carried out pushing or pushing out of the starting shaft or the starting pit, and the non-zugfest interconnected jacking pipes simultaneously correspond to the product pipes to be laid.

With this method, bore lengths up to approx. 500 m and borehole diameter of more than 2,000 mm can be achieved. In addition, microtunnelling can be used in almost all soil types (loose rock, rock) and in almost all groundwater levels with water pressures (up to 3 bar, possibly more).

Although the use of eg steel or PE pipes is in principle possible, but unusual due to the associated technical difficulties. PE pipes, for example, have a very low compressive strength (about 10 N / mm ² ) and thus severely limit the possible laying range. Although steel pipes are to be loaded axially high, but must also be installed in the starting area pipe by pipe and thereby welded together. This means several disadvantages for practical use. First, the welding is great Steel pipes require time-consuming and complicated work (exact alignment and centering required), during their implementation, the actual drilling activity must be interrupted. On the other hand, the welds can not be subjected to a pressure test before laying, which is almost imperative, for example, when installing gas high-pressure lines or oil lines, as a subsequent repair under the obstacle is practically impossible.

Other disadvantages can be seen in the fact that steel pipe strands are very difficult to control and therefore such a drive must provide a planned usually straight laying and that the pipe casing (to protect the steel in the soil from corrosion) during propulsion through the direct contact with the borehole wall heavily loaded and not infrequently damaged.

Finally, it should be noted that when using steel or PE pipes, which are designed as a pressure line during driving there is no possibility to lubricate the outer shell of the pipes (eg with bentonite), resulting in significant increase in the lateral friction occurring leads and thus negatively affects the achievable bore length.

The relevant piping (pressure pipes made of steel, PE etc.) can thus be moved only indirectly by microtunnelling by conventionally a larger Schutzrohrtour from normal jacking pipes (concrete, polycrete, etc.) is laid, then then retracted or inserted the actual product pipe string becomes. The disadvantages associated with this process are obvious - creation of an actually too large borehole (for the thermowells), costs for remaining in the ground thermowells, additional operation for the subsequent retraction of the product tubing, costs through other equipment such as winches or the like.

Despite all these disadvantages, the method described (microtunneling) represents the state of the art for laying pressure pipelines in soils that can not be controlled by means of the controllable horizontal drilling technique described below (US Pat. Tunnels & Tunneling International, March 2005, pp. 18-21 ).

The third to be mentioned in the context set forth laying method is the controllable horizontal drilling technique (abbreviation "HDD" for Horizontal Directional Drilling). This three-phase process (pilot drilling, expansion bore, retraction process) can only be used to lay tensile-strength pipes (made of steel, PE or cast iron, for example). The achievable length of the geometric laying services is greater than that of microtunneling (> 2,000 m), but below that of the achievable pipe diameters (maximum of 1,400 mm).

The biggest disadvantage of the HDD is its high sensitivity to the current ground conditions. In particular, gravelly, gravelly or stony soils with few cohesive fractions lead to problems almost regularly if boreholes with a relatively large diameter have to be created before the drawing process (> 800 mm).

The essential reason for this. Difficulties lie in the fact that in the case of the HDD the borehole alone is supported by the pumped drilling fluid (ie no interim pipes are installed). With unstable ground formations and large borehole diameters, however, it is often not possible to achieve the required stability. Rather, the initially created hole falls after some time again in some areas. Thus, the entry of a pipeline is almost always impossible and laying by HDD is then failed ( Tunnels & Tunneling International, March 2005, pp. 18-21 ).

Additional difficulties for the HDD process such as stones, which occur when pipe between the borehole wall and Jamming or damaging the pipe string and the large borehole diameters sometimes very high torques (eg when drilling in rock), which must be transmitted through the relatively thin drill pipe to the drill head and often cause the breakage of the linkage, are mentioned here only in passing. Similarly, the fact that the diameter of the borehole when using the HDD technique is procedurally about 1.3 to 1.5 times larger than the diameter of the product tubing to produce (otherwise danger of fouling due to sediment and sediment in the borehole). This aspect is technically and economically unfavorable.

As an interim conclusion it can be stated that none of the described laying methods is able to safely and effectively lay a large-diameter, high-tensile, long-length pipeline in difficult subsoil formations.

Out EP 0 291 193 A1 a method for laying pipes is known, which is classified in the category of the aforementioned pilot pipe drives. In this case, a borehole is generated from a starting point by advancing a drill string to a target point, wherein the borehole can also be curved. After reaching the target point, a product pipe string is coupled and pulled in towards the starting point. Basically, in this method, the jacking pipes forming the drill string have a fairly small diameter of the order of about 100 mm. These jacking pipes do not stabilize the drilling channel. When the product tubing string is retracted, the wellbore is generally expanded by means of an extension drill. Upon retraction of the product tubing, a cementitious material is also introduced into the wellbore to stabilize a gap between the borehole wall and the product tubing. Only when a product tubing having a diameter of less than about 100 mm is to be used, eg a telephone cable, is it not necessary to widen the original wellbore.

The present invention is therefore the object of a trenchless laying of properly manufactured and tested, tensile strength pipes with a relatively large diameter (eg, about 800 mm - 1,400 mm) over relatively large laying lengths (eg, about 250 m - 750 m) difficult soil types (such as gravel, gravel, rock, etc.) to make economic conditions possible.

This object is achieved by a method for laying pipes with the features of claim 1. Advantageous embodiments of the invention will become apparent from the dependent claims.

In a preferred embodiment of the method according to the invention, a controlled pipe advance under an obstacle is guided from a starting point to a destination point, wherein the borehole is already widened to the final diameter in the first working step. The soil dislodged by the drilling head during the drilling process is hydraulically conveyed out of the borehole. The bit is decoupled from the first jacking tube after reaching the target point, and the first jacking tube is coupled to a connecting tube at the target point. The connecting pipe is connected on the other side to the product pipe string prepared in one piece on the ground surface. This product tubing is installed in the borehole by a tensile force exerted on the zugfest interconnected jacking tubes tensile forces and thereby the jacking pipes are successively pulled to the starting point, while the tensile strength connected to the jacking pipes connecting pipe and the tensile strength connected to the connecting pipe product tubing pulled into the well become. The product tubing is thus laid trenchless.

The combination of these features is not met by any of the existing methods.

The method according to the invention is a controllable method, with the aid of which (length of the bore) preassembled tubes (diameter eg approx. 800 mm - 1,400 mm) of tensile materials (eg steel, PE, etc.) over a large laying length (about 250 m - 750 m) can be drawn into a curved borehole in almost all soil types and under all groundwater levels, whereby the soil loosened at the drill head is removed and hydraulically removed (ie no soil displacement). The starting point of the hole can be both in an excavation near the terrain surface as well as in a shaft, while the target point is usually in an excavation near the terrain surface.

Fig. 1

eine schematische Darstellung von prinzipiellen Einsatzmöglichkeiten des erfindungsgemäßen Verfahrens, und zwar in Teil

• a) eine Bohrlinie von einer Baugrube unter einem Hindernis zu einer Baugrube,
• b) eine Bohrlinie von einem Startschacht unter einem Hindernis zu einer Baugrube,
• c) eine Bohrlinie von einer Baugrube unter einem Hindernis zu einem Zwischenschacht und von dort unter einem weiteren Hindernis zu einer Baugrube und
• d) eine Bohrlinie von einem Startschacht unter einem Hindernis zu einem Zwischenschacht und von dort unter einem weiteren Hindernis zu einer Baugrube,

Fig. 2

eine prinzipielle Darstellung des erfindungsgemäßen Verfahrens bei einer Bohrlinie von einem Startschacht unter einem Hindernis zu einer Baugrube, und zwar in Teil

1. a) prinzipielle Darstellung der Startsituation,
2. b) prinzipielle Darstellung der Erstellung des Bohrlochs,
3. c) prinzipielle Darstellung der Vorbereitungen für den Einzug eines Produktrohrstrangs,
4. d) prinzipielle Darstellung des Einzugs des Produktrohrstrangs und
5. e) prinzipielle Darstellung der Einbindung des komplett eingezogenen Produktrohrstrangs in eine angrenzende Pipeline,

Fig. 3

eine prinzipielle Darstellung des erfindungsgemäßen Verfahrens bei einer Bohrlinie von einem Startschacht unter einem Hindernis zu einem Zwischenschacht und von dort unter einem weiteren Hindernis zu einer Baugrube, und zwar in Teil

1. a) prinzipielle Darstellung der Startsituation,
2. b) prinzipielle Darstellung der Erstellung der Bohrlöcher,
3. c) prinzipielle Darstellung der Vorbereitungen für den Einzug eines Produktrohrstrangs,
4. d) prinzipielle Darstellung des Einzugs des Produktrohrstrangs,
5. e) prinzipielle Darstellung der Einbindung des komplett eingezogenen Produktrohrstrangs in eine angrenzende Pipeline,

Fig. 4

eine prinzipielle Darstellung einer innerhalb der Vortriebbsrohre liegenden Zugvorrichtung sowie deren Anschluss an eine Pressstation und den Produktrohrstrang,

Fig. 5

eine prinzipielle Darstellung eines zweiteiligen Vortriebsrohres bestehend aus einem Innenrohr sowie einer im Durchmesser anpassbaren Aufdoppelung,

Fig. 6

eine beispielhafte Darstellung der erforderlichen Bohrlochquerschnitte für die Verlegeverfahren Microtunneling, Horizontalbohrtechnik und erfindungsgemäßes Verfahren, dargestellt für einen Produktrohrstrang mit 1.130 mm Außendurchmesser (Innendurchmesser 1.100 mm), und

Fig. 7

eine prinzipielle Darstellung einer in einen Strang aus Vortriebsrohren integrierten Zwischenpressstation.

In the following the invention will be described in more detail with reference to embodiments. The drawings show in

Fig. 1

a schematic representation of basic applications of the method according to the invention, in part

• a) a drilling line from an excavation under an obstacle to an excavation pit,
• b) a drill line from a launch shaft under an obstacle to an excavation pit,
• c) a drilling line from an excavation under an obstacle to an intermediate shaft and from there under another obstacle to a pit and
• d) a drilling line from a launch shaft under an obstacle to an intermediate shaft and from there under another obstacle to an excavation pit,

Fig. 2

a schematic representation of the method according to the invention in a drilling line from a launch shaft under an obstacle to a pit, in part

1. a) basic presentation of the starting situation,
2. b) basic representation of the creation of the borehole,
3. c) a basic description of the preparations for the intake of a product pipeline,
4. d) schematic representation of the intake of the product pipe string and
5. e) basic representation of the integration of the completely drawn-in product pipeline into an adjacent pipeline,

Fig. 3

a schematic representation of the method according to the invention in a drilling line from a launch shaft under an obstacle to an intermediate shaft and from there under another obstacle to an excavation, in part

1. a) basic presentation of the starting situation,
2. b) basic representation of the creation of the boreholes,
3. c) a basic description of the preparations for the intake of a product pipeline,
4. d) basic representation of the intake of the product pipe string,
5. e) basic representation of the integration of the completely drawn-in product pipeline into an adjacent pipeline,

Fig. 4

a schematic representation of lying within the Vortriebbsrohre pulling device and their connection to a pressing station and the product pipe string,

Fig. 5

a schematic representation of a two-part jacking tube consisting of an inner tube and a diameter-adjustable doubling,

Fig. 6

an exemplary representation of the required hole cross-sections for the laying method microtunnelling, horizontal drilling and inventive method, shown for a product tubing with 1,130 mm outer diameter (inner diameter 1,100 mm), and

Fig. 7

a schematic representation of an integrated in a strand of jacking pipes intermediate press station.

Two basic scenarios can be distinguished for the method according to the invention.

In the first scenario ( Fig. 1a, Fig. 1b ), the inventive method of a starting point 1 under an obstacle 7 or several obstacles 7a, 7b, etc. to a target point 6, wherein the starting point either on the terrain surface 17 or in close proximity to the terrain surface 17 in a pit 16 a or but can also lie in a launch shaft 14, while the target point 6 in principle at the Terrain surface 17 or in the immediate vicinity of the terrain surface 17 is located in a pit 16b.

In the second scenario ( Fig. 1c, Fig. 1d ) can be between the starting point 1 and the destination point 6, an intermediate shaft 15 or more intermediate shafts 15a, 15b, etc. are. Between the starting point 1 and the destination point 6, there are usually once again an obstacle 7 to be crossed or several obstacles 7a, 7b to be traversed, etc.

The method according to the invention and the devices which can be used in this case for typical applications will be described below by way of example and in detail.

example 1

In the first example (see Fig. 2a - 2e ) is the starting point 1 in a launch shaft 14 and the target point 6 in a pit 16 b near the terrain surface 17th

First, in the launch shaft 14 a drilling device consisting inter alia, but not exclusively from the components press device 2, pressure ring 18, drill head 3 and jacking pipes 4 prepared and set up. This is essentially a conventional microtunnelling or pipe driving device ( Fig. 2a ).

With the help of this drilling device a bore along a predetermined drilling line 5 is driven in accordance with the valid technical rules for controlled pipe jacking, the drill head 3 is acted upon by the pressing device 2 via the pressure ring 18 and the jacking pipes 4 with the required for the drilling pressure force. Furthermore, the jacking pipes 4 stabilize the drilling channel, so that a collapse of the borehole is excluded even in non-stable formations. The measurement of the position of the drill head 3 and the control of the same along the predetermined drilling line 5 are also made according to the common techniques of controlled pipe jacking ( Fig. 2b ).

After the drill head 3 has arrived at the destination point 6 in the excavation 16b, the drill head 3 is separated from the jacking pipes 4. Thereafter, the first jacking pipe 4 is connected via a connecting pipe 8 with the prepared in length of the bore product pipe string 9 tensile strength ( Fig. 2c ).

In the next step, the over-firm connections coupled propulsion pipes 4 are withdrawn from the press device 2 by means of the pull ring 19 - which was interchangeably replaced at the presser 2 against the pressure ring 18 - through the well, at the same time the connecting pipe 8 and the product pipe string 9 in Direction starting point - along the drilling line 5 - to be moved. In the launch shaft 14, the individual jacking pipes are successively dismantled and removed from the starting shaft 14. In this case, the no longer required connection lines, which provide the drill head with electrical and / or hydraulic energy and control signals during the hole bushing and allow the Bohrspülungsver- and disposal (conveyor and feed line), separated at the coupling points of the jacking pipes 4 and also off the shaft 14 removed. This process is continued until the connecting pipe 8 and the beginning of the product pipe string 9 have arrived in the starting shaft 14 ( Fig. 2d ).

Now the connecting pipe 8 is separated from the product pipe string 9 and removed from the starting shaft 14. The pressing device 2 and the pull ring 19 are now dismantled and removed from the starting shaft 14. Finally, the product pipe string 9 can be connected to the pipeline 12a and 12b and the start shaft 14 can be filled or dismantled ( Fig. 2e ).

Example 2

In a second example (see Fig. 3a - 3e ) is the starting point 1 also in a start shaft 14, between the starting point 1 and the destination point 6, however, there is an intermediate shaft 15. This constellation may be required if the distance between the starting point 1 and the destination point 6 is too large to a single hole ( Fig. 3a ).

In a preferred application, two bores with two separate drilling devices consisting of the components pressing devices 2a and 2b, pressure rings 18a and 18b, drilling heads 3a and 3b and jacking pipes 4a and 4b are now executed simultaneously as described above. In this case, the one hole between start shaft 14 and intermediate shaft 15 and the other bore between intermediate shaft 15 and target point 6, respectively along the predetermined drilling line 5 (FIG. Fig. 3b ).

After both holes have reached their respective target points, the drill heads 3a and 3b are removed from the jacking pipes 4a and 4b. At the same time the jacking pipes 4a and 4b are connected to each other by means of additional jacking pipes in the intermediate shaft and secured against buckling by means of a special guide device 13 in the intermediate shaft area. In this case, the inner region of the guide device 13 can be filled with lubricant (for example bentonite suspension) in order to reduce the frictional forces during the drawing-in process. Thereafter, the first propulsion pipe 4b is connected via a connecting tube 8 with the prepared in length of the bore product pipe string 9 tensile ( Fig. 3c ).

In the next step, the jacking pipes 4a and 4b, which are coupled together by means of tension-resistant connections, are withdrawn through the borehole by the pressing device 2a by means of the draw ring 19, which in the meantime has been replaced by the pressing device 2a against the pressure ring 18a at the same time the connecting pipe 8 and the product pipe string 9 in the direction of starting point - along the drilling line 5 - to be moved. In the launch shaft 14, the individual jacking pipes are successively dismantled and removed from the starting shaft 14. In this case, the no longer required connection lines that provide the drill head 3a with electrical and / or hydraulic energy and control signals during the hole bushing and allow the Bohrspülungsver- - disposal (conveyor and feed line), separated at the coupling points of the jacking pipes 4a and also removed from the shaft 14. This process is continued until the connecting pipe 8 and the beginning of the product pipe string 9 have arrived in the starting shaft 14 ( Fig. 3d ).

Now the connecting pipe 8 is separated from the product pipe string 9 and removed from the starting shaft 14. The pressing device 2 a and the pull ring 19 are now dismantled and removed from the starting shaft 14. Finally, the product pipe string 9 can be connected to the pipeline 12a and 12b, and the start shaft 14 and the intermediate shaft 15 can be filled or dismantled ( Fig. 3e ).

Example 3

Another preferred application (see FIG. 4 ) is, for example, when the hole initially with conventional, that is only driven by pressure, but not zugfesten jacking pipes 4.

In this application, it is provided to transfer the required tensile forces via a pulling device 11 located in the interior of the jacking pipes from the pressing device 2 and the intermediate pull ring 19 to the connecting pipe 8. In this case, the connecting pipe 8 then exerts a compressive force on the jacking pipes 4, while at the same time exerting a tensile force on the product pipe string 9 ( Fig. 4 ).

The installation of the pulling device 11 in the jacking pipes 4 can be carried out simultaneously with the installation of the jacking pipes 4 during the hole preparation, or even subsequently, after the drill head 3 has been removed at the destination point 6.

In a further preferred application, the necessary lines for the Bohrspülungskreislauf (conveyor and feed line) can be used as puller 11 during Einziehvorgangs, for this purpose, they are before the Einziehvorgangs according to the pull ring 19 at the starting point 1 and the connecting pipe 8 at the destination point. 6 connect to.

Example 4

Optionally, the jacking pipes 4 can also be made in two parts, see FIG. 5 , In this case, in a preferred embodiment, it is provided to use an inner tube 21 with a relatively small diameter (eg 600 mm) around which a doubling 20a or 20b is mounted depending on the outer diameter of the product tube strand 9 to be laid.

This makes it possible, the same, relatively complex constructed inner tube - in which, for example, already necessary for the supply and control of the drill head supply and connecting lines 22 are integrated - to use for different outer diameter of the product pipe string 9 by a correspondingly matching doubling 20a, 20b, etc. is mounted. In the exemplary embodiment has the on the left side of FIG. 5 illustrated doubling 20a an outer diameter of 800 mm and the right side of FIG. 5 shown doubling 20b an outer diameter of 1200 mm.

In addition, in a preferred embodiment of the jacking pipes 4, a detent 23 may be provided which prevents that the jacking pipes rotate against each other during the hole bushing or during the Einziehvorgangs.

Example 5

Due to the intended procedure, it is possible to optimally adjust the required boreholes in their diameter to the diameter of the product pipe string 9. As a result, the required well volume is reduced to a minimum, which in particular reduces the technical risk of construction and simultaneously reduces the construction costs.

This situation is in Fig. 6 by way of example for a product tubing having the outer diameter of 1,130 mm, wherein the respective borehole diameters of the different methods for this example have been dimensioned according to the recognized rules of the art. The following table shows the associated numerical values: MT HDD New well 1,850 mm (ID) 1,500 mm (ID) 1,200 mm (ID) thermowell 1,800 mm (OD) - - product pipe 1,130 mm (OD) 1,130 mm (OD) 1,130 mm (OD) Borehole volume (per meter borehole) 2.69 m ³ = 100% 1.77 m ³ = 66% 1.13 m ³ = 42%

Example 6

If the propulsion forces during the creation of the bore along the drilling line 5 exceed the capacity of the pressing device 2 or the strength of the jacking pipes 4, it is possible, analogous to the procedure in Microtunneling, to integrate so-called Zwischenpress- or Dehnerstationen 24 in the propulsion train, please refer FIG. 7 ,

These are essentially press devices that are installed in pipes similar to the jacking pipes 4. However, unlike microtunnelling applications, the method of the invention provides a bi-directional device, i. With the intermediate pressing station, both compressive and tensile forces can be exerted on the propulsion tubes 4 adjoining on both sides.

It can usually be assumed that the forces required during the creation of the bore itself are higher than when pulling the Produktrohrstxangs 9, eg as the contact forces for the drill head 3 accounts and, inter alia, the skin friction through the optionally larger to be selected annular gap and the During the drilling process, "modeling" of the borehole wall and the resulting lubricating film was less than during the drilling process itself. For these reasons, it may be provided that the actual drawing-in process is carried out solely by the pressing station 2.

LIST OF REFERENCE NUMBERS

1

starting point

2

Pressing device (a, b, etc.)

3

Drill head (a, b, etc.)

4

Jacking pipes (a, b, etc.)

5

drilling line

6

Endpoint

7

Obstacle (a, b, etc.)

8th

connecting pipe

9

Product pipe run

10

roller conveyor

11

hitch

12

Pipeline (a, b)

13

Guide device in intermediate shaft

14

starting shaft

15

Intermediate shaft (a, b, etc.)

16

Excavation pit (a, b)

17

ground surface

18

Pressure ring (a, b, etc.)

19

pull ring

20

Doubling (a, b, etc.)

21

inner tube

22

Connection and supply lines

23

lock

24

Dehner station

Claims (15)

1. A method for laying pipes, in which a controlled heading is carried out from a starting point (1) under an obstacle (7a, 7b) to a finishing point (6), a drill hole being created during the heading by a drill head (3; 3a, 3b) and the drill head (3; 3a, 3b) being pressed forward by means of a pressing device (2; 2a, 2b) over a heading run made up of heading pipes (4; 4a, 4b), wherein

   - the drill hole is already expanded to the final diameter in the first working step,

   - the soil loosened by the drilling head (3; 3a, 3b) during the drilling operation is removed and transported out of the drill hole, preferably hydraulically,

   - after the finishing point (6) is reached, a product pipe run (9), which is prepared on the surface of the land, preferably in one piece, and has product pipes which are connected to one another in a tension-resistant manner, is coupled on and

   - the heading pipes (4; 4a, 4b) are successively drawn back to the starting point (1), the product pipe run (9) simultaneously being drawn after them into the drill hole and consequently laid without a trench,

   characterized in that

   - the drill hole is stabilised by the heading pipes (4; 4a, 4b),

   - the product pipes comprise a diameter of at least 800 mm, and

   - optionally at least one intermediate shaft (15) is provided between the starting point (1) and the finishing point (6).
2. The method as claimed in claim 1, characterized in that

   - the soil loosened by the drilling head (3; 3a, 3b) during the drilling operation is hydraulically transported out of the drill hole,

   - after the finishing point (6) is reached, the drilling head (3; 3b) is decoupled from the first heading pipe (4; 4b),

   - the first heading pipe (4; 4b) is coupled to a connecting pipe device (8) at the finishing point (6),

   - the connecting pipe device (8) is connected at its end opposite from the first heading pipe (4; 4b) in a tension-resistant manner to a product pipe run (9), which is prepared in one piece on the surface of the land and has product pipes which are connected to one another in a tension-resistant manner,

   - the product pipe run (9) is inserted into the drill hole, in that a pressing device (2, 2a) exerts forces on the heading pipes (4; 4a, 4b) and, as a result, the heading pipes (4; 4a, 4b) are successively drawn to the starting point (1), the connecting pipe device (8) and the product pipe run (9) connected to the connecting pipe device (8) simultaneously being drawn after them into the drill hole and the product pipe run (9) consequently being laid without a trench.
3. A method for laying pipes, in which a controlled heading is carried out from a starting point (1) under an obstacle (7a, 7b) to a finishing point (6), a drill hole being created during the heading by a drill head (3a, 3b) and the drill head (3a, 3b) being pressed forward by means of a pressing device (2a, 2b) over a heading run made up of heading pipes (4a, 4b),

   - wherein an intermediate shaft (15) is installed between the starting point (1) and the finishing point (6) and a bore is driven from the starting point (1) to the intermediate shaft (15) and, approximately at the same time, a bore is driven from the intermediate shaft (15) to the finishing point (6), separate drilling equipment being used, the soil loosened by the respective drilling heads (3a, 3b) during the drilling operation being removed and hydraulically transported out of from the respective drill holes,

   - the drill holes being already expanded to the final diameter in the first working step and being stabilised by the heading pipes (4a, 4b),

   - wherein, after the intermediate shaft (15) or the finishing point (6) is reached, the drilling heads (3a, 3b) are decoupled from the respective first heading pipes (4a, 4b),

   - wherein the heading pipes (4a, 4b) of the respective individual bores are connected to one another in the intermediate shaft (15), a guide (13) for the heading pipes (4a, 4b) being made in the area of the intermediate shaft (15),

   - wherein the first heading pipe (4b) is coupled to a connecting pipe device (8) at the finishing point (6) and the connecting pipe device (8) is connected on the other side to a product pipe run (9) prepared in one piece on the surface of the land,

   - the product pipe run (9) comprising product pipes being connected in a tension-resistant manner and having a diameter of at least 800 mm,

   - wherein the product pipe run (9) is fitted into the drill hole, in that the pressing device (2a) located at the starting point (1) exerts forces on the heading pipes (4a, 4b) that are connected to one another and, as a result, the heading pipes (4a, 4b) are successively drawn to the starting point (1), the connecting pipe device (8) connected to the heading pipes (4a, 4b) and the product pipe run (9) connected to the connecting pipe device (8) simultaneously being drawn after them into the drill hole and the product pipe run (9) consequently being laid without a trench.
4. A method analogous to claim 3, characterized in that more than one intermediate shaft is installed between the starting point (1) and the finishing point (6).
5. The method as claimed in claim 3 or 4, characterized in that, at the guide (13) in an intermediate shaft (15), lubricant is fed into an annular space between the guide (13) and the heading pipes (4a, 4b) or product pipe run (9).
6. The method as claimed in one of claims 1 to 5, characterized in that the starting point (1) and the finishing point (6) lie in an open excavation (16a, 16b).
7. The method as claimed in one of claims 1 to 5, characterized in that the starting point (1) lies in a shaft (14) and the finishing point (6) lies in an open excavation (16b).
8. The method as claimed in one of claims 2 to 7, characterized in that the heading pipes (4; 4a, 4b) are connected to one another in a tension-resistant manner and in that the first heading pipe (4; 4b) is coupled in a tension-resistant manner to the connecting pipe device (8) at the finishing point (6).
9. The method as claimed in one of claims 2 to 8, characterized in that the drawing force required for the drawing-in operation is transmitted from the pressing device (2) to the connecting pipe device (8) via a drawing ring (19) by means of a drawing device (11) located inside the heading pipes (4).
10. The method as claimed in one of claims 1 to 9, characterized in that the heading pipes (4; 4a, 4b) have a greater outside diameter than the product pipe run (9).
11. The method as claimed in one of claims 1 to 10, characterized in that the heading pipes (4; 4a, 4b) have at the connecting surfaces arresting means (23) which prevent twisting of the heading pipes (4; 4a, 4b) in the drill hole.
12. The method as claimed in one of claims 1 to 11, characterized in that, in heading pipes (4; 4a, 4b), devices for feeding lubricant into the annular space between the heading pipe (4; 4a, 4b) and the wall of the drill hole are provided.
13. The method as claimed in one of claims 2 to 12, characterized in that the annular space between the product pipe run (9) and the wall of the drill hole is lubricated during the drawing-in operation, preferably by means of devices which are integrated in the connecting pipe device (8).
14. The method as claimed in one of claims 2 to 13, characterized in that vibrations, with the aid of which the frictional forces occurring during the drawing into the drill hole are decreased, are exerted on the product pipe run (9) by means of a vibrating device arranged in the connecting pipe device (8).
15. The method as claimed in one of claims 1 to 14, characterized in that at least one intermediate pressing station (24), which acts on both sides and is connected to the neighboring heading pipes (4) in a compression-resistant and tension-resistant manner, is arranged in the heading run.

Images