(51) Int. Cl.3:

                                                                                                                                        E 21 B, 7/04

                                                                                                                                        E 21 C, 9/00

(19)      Federal Republic of Germany

                        [emblem]

            German Patent Office

 

(12)                                                         Offenlegungsschrift

                                                       [Published Patent Application]

(11)                                                          DE 30 00 239 A1

           

(21)      Application number:                  P 30 00 239.2-24

(22)      Filing date:                    January 5, 1980

(43)      Disclosure date:                        July 16, 1981

 

(71)      Applicant:                                 Bergwerksverband GmbH, 4300 Essen, DE

 

(61)      Supplement to:              P 30 46 122.4

 

(72)      Inventors:                                 Wallussek, Heinz, 5804 Herdecke, DE;

                                                            Wiebe, Martin, 4320 Hattlingen, DE;

                                                            Röder, Thomas, 4690 Herne, DE

 

Request for an examination has been filed, pursuant to § 44 of the Patent Act.

 

 

(54)      Device for Boring Target Directed Boreholes

 

 

DE 30 00 239 A1

                                                          ORIGINAL INSPECTED

                                                                                                   Federal Government Printing Office of Berlin 05.81 130 029/40   6/60


 

 

                                        Device for Boring Target Directed Boreholes

 

Patent Claims:

 

1.         Device, which is intended for boring target directed boreholes, in particular drill holes in coal mining, and which consists of a directional drill pipe, which is disposed behind the drill bit in the drill pipe string, characterized in that the directional drill pipe (1) exhibits an internal, rotatably mounted section (3) and an external, stationary section (4), whereby the electric inclinometers (14) and the adjustable, swivellably mounted control bars (9) are disposed on or in the external stationary section.

 

2.         Device, as claimed in claim 1, characterized in that the control bars (9) are mounted on the head (2) of the directional drill pipe (1) and can be swung out by means of hydraulically drivable cylinders (10, 11), which are arranged in the upper section (6) of the directional drill pipe.


3.         Device, as claimed in claim 1 and claim 2, characterized in that the inclinometers (14) are assigned solenoid valves (16, 17) that regulate the supply of the cylinders (10, 11).

 

4.         Device, as claimed in claim 1 and claim 2, characterized in that the inclinometers (14) are arranged cross-wise.

 

5.         Device, as claimed in claim 1, characterized in that an eccentric is mounted on the rotatably mounted section (3) of the directional drill pipe (1).

 

6.         Device, as claimed in claim 1, characterized in that pressure-limited hydraulic accumulators (20) are connected between the pressure generator (19) and the cylinder (10, 11).

 

7.         Device, as claimed in claim 1, characterized in that the external, stationary section (4) of the directional drill pipe (1) exhibits a dynamo, which can be driven by means of the rotatably mounted section (3) and supplies power to the batteries, which are housed in the directional drill pipe.

 


 

                                        Device for Boring Target Directed Boreholes

 

 

The invention relates to a device, which is intended for boring target directed boreholes, in particular drill holes in coal mining, and which consists of a directional drill pipe, which is disposed behind the drill bit in the drill pipe string.

 

Such devices are used to advance the boreholes as close as possible to the predetermined target. Such target directed boreholes are very important for exploratory work, supply and service or rescue boreholes.

 

It is known to dispose a rigid directional drill pipe behind the drill bit in order to stabilize the drill pipe string. These directional drill pipes can only stabilize the drill pipe string, but cannot prevent the borehole from slanting. In particular, such directional drill pipes do not allow a correction of the variation from the predetermined drilling direction that gradually develops in the course of the drilling operation. It is especially disadvantageous that the deviation that occurs during the drilling operation cannot be determined with accuracy until the target location has been reached. Moreover, attempts have been made to employ more or less automatically operating directional drill pipes by means of a pendulum control unit.


Any adjustment errors or system failures in the relatively expensive control unit can result in deviations that can be determined only at the target location or after completion of the borehole. The cause of such faulty drilling can also be the inertia range that exists in the system of the pendulum control unit.

 

The invention is based on the problem of providing a device, by means of which the course of the drill hole can be both checked and corrected.

 

The invention solves this problem, in that the directional drill pipe exhibits an internal, rotatably mounted section and an external, stationary section. In this case electric inclinometers and the adjustable, swivellably mounted control bars are disposed on or in the external stationary section.

 

A directional drill pipe that is equipped in such a way allows a continuous checking of the course of the borehole by means of the electric inclinometers and allows a corresponding correction by means of the control bars, which can be slid out of the external stationary section. In so doing, it is possible to report the deviation, indicated by the electric inclinometer, over the measurement cables in the drill pipes as far as to the operator's control station, where an evaluation takes place; and from where corresponding counter-measures are initiated and/or the corresponding control bars are activated.


The checking and controlling is carried out section by section preferably during the breaks in the drilling operation, because in this period of time jolts and any other error sources are eliminated, but the measurement and control can also be carried out during the drilling operation.

 

It is practical to counteract a variation in the borehole with the aid of a directional drill pipe that is equipped in such a way that the control bars are mounted on the head of the directional drill pipe and can be swung out by means of hydraulically drivable cylinders, which are arranged in the upper section of the directional drill pipe. In this way the requisite corrections can be carried out with minimum cylinder movements. In particular, the corrections can be carried out by sliding out the control bars in the same way as the umbrella rods in an umbrella. At the same time such a displacement and arrangement of the control bars guarantees maximum protection for the parts that are required for the control unit.

 

One embodiment of the invention provides that the inclinometers are assigned solenoid valves that regulate the supply of the cylinders. In this context the solenoid valves are adjusted in such a way that they activate the externally mounted control bars as a function of the inclinometer data.

 

In order to check and avoid erroneous measurements it is practical to arrange the inclinometers cross-wise. Then the erroneous measurements can be easily ascertained from the operator's control station and eliminated by a correcting intervention.


The necessary operating pressure for the hydraulic control unit is generated preferably in the directional drill pipe itself. For this purpose the invention provides that the rotatably mounted section of the directional drill pipe exhibits an eccentric, by means of which the necessary operating pressure can be generated. As a result, the pressure-limited hydraulic accumulators, which are connected between the pressure generator and the cylinder, make it possible to activate the cylinders even during the breaks in the drilling operation.

 

The power for the electric inclinometers and the solenoid valve control unit is supplied selectively via rotary transformers over a cable reservoir, which is carried along, or over hardwired conductors in the pipe casings with contact rings in the pipe couplings or via transmission of the measured values and control commands according to the telemetric method or also in an especially expedient way by means of a dynamo. To this end it is provided that the external, stationary section of the directional drill pipe exhibits such a dynamo, which can be driven by means of the rotatably mounted section and supplies power to the batteries, which are housed in the directional drill pipe.

 

One important advantage of the invention lies in the fact that the faulty run of a borehole can be easily determined by checking measures, which can be repeated as often as desired, and can be eliminated by means of the corresponding corrective measures. As a result, the additional costs, which are often considerable, and the drilling time, associated with the faulty run of a borehole, are avoided.


The technological progress of the invention lies especially in the possibility of making an automatic correction with such a directional drill pipe in the event of a deviation from the predetermined drilling direction while at the same time the course of the drilling operation can be checked from the operator's control station. Furthermore, the technological advancement also lies in the ability to operate the measurement and control members in the drill pipe without an additional supply of energy.

 

One embodiment of the invention is depicted in the drawing and is explained in detail below.

 

Figure 1            depicts the inventive directional drill pipe, to some degree from a cross sectional view.

 

The drawing in Figure 1 that is largely a schematic drawing shows that the directional drill pipe 1, which is installed in the drill pipe string, consists in essence of the internal, rotatably mounted section 3 and the external stationary section 4. The fluid passage 22 runs down the middle in the directional drill pipe 1. Said fluid passage supplies the drill bit (not illustrated) with drilling fluid.

 

On the head 2 of the directional drill pipe 1, the control bars 9 are connected by means of holders 8 to the stationary section 4 of the directional drill pipe 1. These control bars 9 can be driven by means of the cylinders 10, 11, which are mounted in the upper section 6 of the directional drill pipe 1,


so that, when said control bars are suitably driven, they issue from the stationary section 4 in the upper section 7 of the directional drill pipe 1. Their movement is made uniform by means of the travel limiters 12. In this case the springs 13, which are assigned to the travel limiters 12, make sure at the same time that the control bars 9 are moved back into their starting position, when the cylinders are in a depressurized state.

 

The cylinders 10, 11 are regulated by the solenoid valves 16, 17, which in turn are controlled by the inclinometers 14. The inclinometers 14 in turn are connected in such a manner that their determined deviations are reported simultaneously over the measurement cables or by a different method to the operator's control station.

 

The necessary operating pressure for the hydraulic control unit is generated by the rotating section of the directional drill pipe 1 and/or by the assigned eccentric 23. The installed, pressure-limited hydraulic accumulators 20 make it possible to operate the cylinders 10, 11 during the breaks in the drilling operation. At the same time the required fluid is taken from the tank 18 by means of the pressure generator 19.

 

In the illustrated example, the power for the electric inclinometers 14 and the solenoid valves 16, 17 is supplied by the cable, which is used simultaneously as the measurement and control cable 15, or according to a different method.


It is also possible to couple the inclinometers directly to the respective control cylinders. In this case, however, the visual inspection cannot be carried out from the operator's control station without any additional cost.


 

                                                                   - Blank Sheet -


key to Figure

 

Number:                       30 00 239

Int. Cl.3:                        E 21 B 7/04

Application date:           January 5, 1980

Disclosure date:            July 16, 1981