ES2773500T3 - Device for producing a hole in the ground - Google Patents

Abstract

Device for producing a hole in the ground with - a carrier (12), - a mast (20) supported on the carrier (12), - a bogie (22) guided so that it can move longitudinally on the mast (20 ), in which a drilling drive (24) is arranged to rotatably drive a drill string (30), - a drilling tool (34) at a lower end of the drill string (30), - a drive of the bogie (40) to move the bogie (22) along the mast (20), wherein the bogie drive (40) comprises a cable drive with a cable winch (46) and a hoisting cable (48) , - a control mechanism (80) to control the drive of the bogie (40), and - a sensor (60) to determine a retraction force applied to the bogie (22), - wherein the control mechanism (80) is configured to emit a control signal to the drive of the bogie (40), by means of which a force d The load of the drill string (30) on the core of the drill hole can be set to a predetermined value, characterized - in that the sensor (60) is configured as a torque capsule, which is arranged at a dead cable end of the cable lift (48) on the mast (20), - because the control mechanism (80) is configured to, based on a retraction force and / or a clamping force, established by the sensor (60) at the cable end dead during the drilling process, and in a self-weight of the drilling branch (30) stored in a memory device (70), establish a real value of the load force of the drilling branch (30), - because the mechanism control (80) is configured to, during the drilling process, feed a difference between the actual value of the load force and the predetermined value of the load force as a deviation from the rule to a PID regulator, which is configured to Send one control variable for driving the bogie 40, and - because the PID controller is configured to carry out two to one hundred iteration steps per second.

Description

DESCRIPTION

Device for producing a hole in the ground

The invention relates to a device for producing a hole in the ground according to the preamble of claim 1. A device of this type comprises a carrier device, a mast supported on the carrier device, a bogie guided so that it can move longitudinally in the mast, in which there is arranged a drilling drive to rotatably drive a drilling leg, and a bogie drive for translating the bogie along the mast. The invention also relates to a method for producing a hole in the ground according to the preamble of claim 6.

The production of a borehole in the ground can be used for different purposes. For example the borehole can be filled to produce a foundation element in the ground with a hardenable filler material. Core drilling can also take place, for example, to produce wells, to explore the ground or in the context of geothermal installations, for example to introduce geothermal probes. Other applications are also possible.

Depending on the state of the soil as well as the drilling tools used, it is necessary to choose differently the drilling parameters, especially the turning speed and the feed rate. If, for example, the feed rate is too low, it is known to increase the rotational speed of the drill string and / or to strengthen the clamping force.

To regulate a drilling process it is also known, from US 7,350,593 B1, to regulate a hydraulic pressure on a drilling rod again.

From document WO 99/39078 A1 a device of the kind set out is deduced.

The invention has set itself the object of disclosing a device and a method for producing a hole in the ground, which makes possible a particularly economical production of a borehole.

The object is achieved according to the invention by a device with the features of claim 1, respectively by a method with the features of claim 6. Preferred embodiments of the invention are set forth in the dependent claims.

The device for producing a hole in the ground is characterized according to the invention in that a control mechanism is provided to control the drive of the bogie and that the control gear is configured to emit a control signal upon drive of the bogie , by which the loading force of the drill string on the core of the borehole can be set to a predetermined value.

A basic idea of the invention consists in executing the control of the drive of the bogie, that is to say the control of the axial advance of the bogie, based on the value of the load force of the drilling branch on the hearth of the borehole. The movement of the bogie along the mast is therefore carried out as a function of the set value of the load force during the drilling process.

The predetermined value of the loading force can be adjusted differently, for example depending on the condition of the ground. For example in the case of a hard soil material, such as stones or rock, a higher loading force or clamping force can be chosen than in the case of a soft soil, for example earthy material.

The predetermined value for the load force can be a constant value over time or variable over time, for example an oscillation. Setting a defined loading force makes a particularly efficient drilling procedure possible. In addition to this, wear on the drilling tools can be reduced. This leads to longer durations and consequently higher profitability.

Preferably a data input unit is provided for inputting a nominal value for the load force, especially by a user of the device. The data input unit is preferably arranged in a user booth of the device. The nominal value can in particular be a constant or time-varying value.

The device preferably contains a measuring mechanism or a sensor to determine the actual value of the loading force. In principle, it is possible for the measuring device or sensor to be arranged in the region of the drilling tool, that is to say in the bottom of the borehole.

However, it is preferable that a sensor is provided with which a retraction force and / or clamping force can be determined, with which the drill string is retracted from the core of the borehole or pressed onto the core of the core. borehole drilling. The retraction force and the clamping force are preferably vertical forces, with which the drill string is actively raised above the drill drive or pressed against the core of the drill hole. In particular, it involves a force with which the drilling drive or the drilling unit is actively pulled or pressed down or up. bogie. The sensor therefore determines the force with which the drill string pulls down or presses up on the bogie or drill drive. Based on the set value of the retraction force and / or the clamping force, the load can be determined or calculated.

If the retraction force and / or the clamping force are zero, the loading force corresponds to the force caused by the self-weight of the drill string. By slightly unloading the drill string or pressing the drill string on the core of the drill hole, the loading force can be reduced or increased. To unload the core from the borehole, the drill string is raised or retracted. For tightening it is actively pressed down.

By means of the additional force, the loading force caused by the self-weight can therefore be changed. The retraction force and / or the clamping force can be applied in particular by driving the bogie to the bogie of the drilling gear. The adjustment of the actual load force is therefore preferably carried out by means of a retraction force and / or clamping force applied to the bogie.

The sensor is preferably arranged outside the borehole, in particular in the region of the bogie, the drill drive and / or the bogie drive. The sensor is in particular a force sensor or force detector, with which the force exerted by the drill string can be determined directly or indirectly by its own weight and / or an additional force applied to the bogie , to the drilling drive and / or the drive of the bogie.

A dynamometric capsule is provided as a sensor. The torque capsule is arranged, in the case of a bogie winch drive, at the dead cable end.

The loading force of the drilling tool or the drilling head on the core of the core hole corresponds to the sum of the gravitational force of the drill string and the additional clamping force or retraction force actively applied. Here it applies:

Fload _ mramal g Fapriete - Fretraction

with

Fload: load force on the borehole console;

branch: weight of the drilling branch;

g: earth acceleration;

p. clamping force towards the core of the borehole _{F clamping:}

Fretraction: force of retraction out of the core of the borehole.

The loading force of the drill string on the core of the drill hole therefore depends, among other things, on the own weight of the drill string. According to the invention it is therefore preferable that the control mechanism is designed to, based on the retraction force established by the sensor, determine the own weight or the gravitational force of the drill string.

For this, for example, the drill string can be raised so that the loading force is zero. The retraction force required for lifting is measured. The retraction force corresponds to the gravitational force, from which the proper weight can be determined if necessary.

A memory device is preferably provided, which is designed to store the established dead weight. Because the self-weight of the drill string remains constant during a drilling process, as long as the drill string is not changed, it is only necessary to determine the self-weight once before performing the drilling process. The self-weight determined and filed once can be used later, during the drilling process, to establish or calculate the actual load force based on the borehole.

It is especially preferable that the sensor is configured to set the retraction force and / or the clamping force during a drilling process. The force sensor is therefore designed to determine the retraction force and / or the clamping force, continuously or repeatedly, during the drilling process.

A particularly reliable and robust determination of the actual loading force can be achieved by means of the control mechanism being configured to set the loading force on the core of the core hole, based on the archived dead weight of the drill string and in the retraction force and / or clamping force exerted during the drilling process.

In order to set a loading force, which is greater than the force caused by the own weight of the drill string, it is preferable that the bogie drive is configured to actively press the drill string towards the core of the drill hole. The drive of the bogie is therefore designed to actively move the bogie, on which the drill string is resting, downwards, in particular to press or pull it.

According to the invention the bogie drive comprises a cable drive with a cable winch and a lifting cable. The cable is preferably guided through the mast, starting from the cable winch, and supports the bogie.

The control mechanism for controlling the bogie is preferably designed as a closed control loop. A constant or time-varying value of the loading force of the drill string on the core of the borehole is used as the nominal value. The actual value of the load force, calculated using the force sensor, is returned as re-coupling and subtracted from the nominal value. The deviation from the rule calculated in this way is fed to a controller, which sends an output value or an actuating variable to drive the bogie.

According to the invention the control mechanism has a PID regulator. It is configured to carry out up to one hundred iteration steps per second. In this way a precise and fast regulation can be obtained. The deviation from the rule, which is preferably calculated by setting the weight of the branch and the modified measurement value by discharging the branch onto the core of the borehole, is fed to a regulator which generates a control signal electrical. It controls, preferably through a proportional valve, the winch or the cylinder of the bogie drive.

The regulation parameters are preferably set at maximum speed, without the system beginning to oscillate. In this way the winch or cylinder raises the linkage when there is too much load on the drilling tool, and lowers the linkage when too little load is placed on the drilling tool. If the rod or drill string is too light for the required clamping force, the rod is actively pressed down.

The hydraulic proportional valve is preferably a valve that is specifically designed for lathe operation. It contains a load holding function and a compensation for the forces induced by the load on the control piston.

The invention is explained further below on the basis of preferred embodiments, which have been represented in the attached schematic figures. In the figures they show:

fig. 1 a general representation of a device according to the invention;

fig. 2 a device according to the invention with a winch drive as a bogie drive;

fig. 3 a device with a cylinder drive as a bogie drive; and

fig. 4 a schematic representation of the forces acting on the drill string.

Fig. 1 shows a device 10 according to the invention with a carrier device 12, for example a carrier vehicle on which a mast 20 is supported, preferably in a tiltable manner. The vertically positionable mast 20 is guided in such a way that a bogie 22 can be moved, which can also be called a trolley. For translating the bogie 22 along a longitudinal axis of the mast 20, a bogie drive 40 is provided. The bogie drive 40 can be designed in basically any way.

Fig. 2 shows a drive of the bogie 40 with a cable winch 46 and a lifting cable 48. The bogie 22 is suspended from the lift cable 48. The lift cable 48 is guided, starting from the cable winch 46 arranged on the carrier 12 through from rollers 19 on the mast 20, in particular on a roller head 18 of the mast 20, to a deflector roller 23 on the bogie 22. From the deflector roller 23 the cable 48 reaches a fixed point on the mast 20 p on the roller head 28. The rope winch 46 controls, through the unwound length of the lifting rope 48, the position of the bogie 22. By means of the deflector roll 23 on the bogie 22 the lifting rope 48 is guided like a hoist .

Another embodiment of a bogie drive 40 is shown in FIG. 3. To move the bogie 22 along the mast 20, a hydraulic cylinder 42 is provided. The hydraulic cylinder 42, which can basically be designed as a one-sided or two-sided cylinder, controls the position of the bogie 22 by means of inserting or removing your plunger. In the embodiment shown, the bogie 22 is connected by means of two pulling cables 44. Through the path of the hydraulic cylinder 42, the position of the bogie 22 is controlled with the aid of the cables 44, which are guided through rollers 26 on the mast 20. The rollers 26 are at a lower end of the mast 20 and at a head of the mast 21.

Above the bogie 22, which may also be called a drilling gear bogie, is a drilling drive 24 for the rotary drive of a drill string 30. The drill string 30 can be fixed axially to the drive drive. drilling 25, such that a vertical force can be transmitted to the drilling branch 30 via the drilling drive 24, which may also be called a rotary force head. By raising or lowering the bogie 22, to which the drilling drive 24 is attached, the loading force of the drill string 30 on the core of the drill hole is thereby increased or decreased.

The drilling branch 30 comprises a drilling rod 32 actuated by the drilling drive 24, at the lower end of which a drilling tool 34 is arranged, which may comprise chisels or drilling teeth.

Fig. 4 shows the forces acting during the drilling process. By lifting or downward pressure of the bogie 22, a retraction force or clamping force is transmitted via the drill rod 32 to the drilling tool 34 and the loading force of the drilling tool 34 is controlled on the core of the borehole 4 of the borehole 2. The drilling process is preferably carried out with a constant load or a predetermined time course of the load.

In the area of the drive of the bogie 40 or in the area of the suspension or linkage of the drill string 30 or the drill string 32 in the drill drive 24, a sensor 60 is arranged to determine the retraction force and / or the clamping force. The sensor 60, which can be especially a force sensor, can be used to determine the self-weight of the drill string 30, by means of which the force that is necessary to lift the drill string 30 is measured. The measured value The self-weight of the drill string 30 can be stored in a memory device 70.

By placing the drill string 30 above the base of the borehole 4, the force measured by the sensor 60 is reduced. If the force equals zero, the load force on the base of the borehole 4 is reduced. corresponds to the force caused by the self-weight of the drill string 30. By applying an upwardly directed retraction force to the bogie 22 or the drill drive 24 attached to it, the loading force can be reduced. By applying a downwardly directed clamping force to the bogie 22 or the drilling drive 24 attached thereto, the actual loading force can be further increased.

To adjust a load force with a predetermined value, a control mechanism 80 is provided. The control mechanism 80 comprises a regulator, which obtains as an input signal a difference between a nominal value of the load force and a real value and generates an output signal, which is used to control the drive of the bogie 40. If the load force is excessively high, an upwardly directed retraction force is exerted on the bogie 22. If the measured value of the load force is excessively low, a downwardly directed clamping force is exerted on the bogie 22.

By controlling the drilling process with the load force as the pilot variable, a particularly preferred drilling process can be obtained. Measurement of the load force by means of a sensor 60 outside the borehole, especially in the bogie 22 or in the bogie drive 40, ensures a reliable and robust measurement. Determining the self-weight of the drill string 30 prior to the start of the drilling procedure, by lifting the drill string 30 from the core of the borehole, enables an indirect determination of the load by measuring the force of retraction or additional tightening actively applied to drill string 30.

Claims (6)

1. - Device to produce a hole in the ground with - a carrier device (12), - a mast (20) supported on the carrier (12), - a bogie (22) guided in a longitudinally displaceable manner on the mast (20), on which a drilling drive (24) is arranged to rotatably drive a drill string (30), - a drilling tool (34) at a lower end of the drilling branch (30), - a bogie drive (40) for moving the bogie (22) along the mast (20), wherein the bogie drive (40) comprises a cable drive with a cable winch (46) and a lifting cable (48), - a control mechanism (80) to control the drive of the bogie (40), and - a sensor (60) to determine a retraction force applied to the bogie (22), - wherein the control mechanism (80) is configured to emit a control signal to the drive of the bogie (40), by means of which a loading force of the drill string (30) on the core of the bore hole can be adjusted to a default value, characterized - because the sensor (60) is configured as a torque capsule, which is arranged at a dead cable end of the hoist cable (48) on the mast (20), - because the control mechanism (80) is configured to, based on a retraction force and / or a clamping force, established by the sensor (60) at the dead wire end during the drilling process, and on a weight of the drilling branch (30) stored in a memory device (70), establish a real value of the load force of the drilling branch (30), - because the control mechanism (80) is configured to, during the drilling process, feed a difference between the actual value of the load force and the predetermined value of the load force as a deviation from the rule to a PID regulator, which is configured to send a control variable to drive the bogie (40), and - because the PID controller is configured to carry out two to one hundred iteration steps per second. 2. - Device according to claim 1, characterized in that a data entry unit is provided to enter a nominal value for the load force 3. - Device according to claims 1 or 2, characterized in that a sensor (60) is provided, with which a retraction force and / or a clamping force can be determined, with which the drilling branch (30) can be retracted from the core of the borehole or pressed against the core of the borehole. 4. - Device according to claim 3, characterized in that the control mechanism (80) is designed to, based on the retraction force established by the sensor, determine the own weight of the drilling branch (30). 5. - Device according to one of claims 1 to 4, characterized in that the drive of the bogie (40) is configured to actively press the drilling branch (30) towards the hearth of the borehole. 6. - Method for producing a hole in the ground with a device (10), according to one of claims 1 to 5, with a carrier (12) and - a mast (20) supported on the carrier (12), along which a bogie (22) is guided in such a way that it can move longitudinally, in which a drilling drive (24) is arranged, which operates rotatably a drilling branch (30), where the bogie (22) is translated along the mast (20) with a bogie drive (40), where the bogie drive (40) has a rope with a rope winch (46) and a hoist rope (48), and - a sensor (60), which determines a retraction force applied to the bogie (22), - where the drive of the bogie (40) is controlled by a control mechanism (80), where the control mechanism (80) emits a control signal to the drive of the bogie (40), by means of which the load force of the drill string (30) on the core of the borehole is set to a predetermined value, characterized - because a dynamometric capsule is used as sensor (60) and it is arranged at one end of the dead cable of the lifting cable (48) in the mast (20), - because the control mechanism (80) establishes, based on a retraction force and / or a clamping force established by the sensor (60) during the drilling process and in an own weight of the drilling branch (30) stored in a memory device (70), a real value of the load force of the drilling branch (30), - because the control mechanism (80) feeds, during the drilling process, a difference between the real value of the load force and the predetermined value of the load force as a deviation from the rule to a PID regulator, which sends an actuating variable for driving the bogie (40) and performs two to one hundred iteration steps per second.