EP3904632A1 - Method and device for lifting a drill string - Google Patents

Abstract

The invention relates to a method for lifting a drill rod attached to a drilling device, in particular a Kelly bar, which is suspended at the upper end on a pulling means guided over a boom of the drilling device can be lowered, wherein a safety device is arranged on the traction means, by means of which the reaching of a defined height of the drill rod can be detected, and wherein a safety distance is provided between the defined height and the boom. The method comprises the steps of: operating the winch to raise the drill pipe; Registering the reaching of the defined height of the drill pipe by means of the safety device; Controlling the winch to decelerate the lifting movement of the drill string; and continuing to raise the drill string a predetermined or determinable distance within the safety distance by operating the winch. The invention also relates to a drilling device with a controller which is set up to carry out the method according to the invention.

Description

The present invention relates to a method for lifting a drill rod attached to a drilling device according to claim 1 and a drilling device with a control for carrying out such a method.

Mobile drilling devices with a drill rod mounted so that it can be adjusted in height by means of a traction device on a mast or leader are known from the prior art. Such drilling devices often work according to the Kelly method, with the drill rod being a multi-telescopic Kelly bar which is attached to a Kelly rope which is guided at the upper end of the mast over a mast head or Kelly gallows and on a Kelly winch Is stored windable. The Kelly bar is usually attached to the Kelly rope via a swivel.

In order to prevent the drilling device from being damaged by lifting the Kelly bar too high due to a collision of the swivel with the gallows, special safety devices can be used, which usually include a counter element moved with the Kelly bar and an associated weight arranged on the pull rope. The height of the weight on the mast or the pull rope defines the maximum possible height of the swivel. Upon reaching this maximum height, the limit switch contacts the weight, which stops the winch and stops the lifting movement of the Kelly bar.

The maximum possible drilling depth of such drilling devices is typically determined by the length of the drill rod or the installable Kelly bar. The maximum length of the Kelly bar is in turn defined by the maximum possible height of the swivel relative to the drilling device and thus by the switching point of the limit switch or the position of the weight. The switching point of the hoist limit switch normally also takes into account a braking distance of the Kelly bar after the winch stop signal, in that the weight is attached at a certain safety distance from the boom. This safety distance must be sufficiently large so that braking from the highest lifting speed or the maximum rotation speed of the Kelly winch is possible without colliding with the boom.

After installing the Kelly bar and attaching the drilling tool, in the fully raised position of the Kelly bar, there remains a distance between the subsurface or planum and the lower edge of the drilling tool, which is also referred to as the "X dimension". This X dimension is important to determine which support tube lengths can be used or whether the bottom of a drilling bucket can be opened.

Against this background, the object of the present invention is to optimize said X dimension without having to make modifications to the drilling device or drill rods.

According to the invention, this object is achieved by a method with the features of claim 1 and by a drilling device with the features of claim 15.

• Betätigen der Winde, um das Bohrgestänge anzuheben,
• Registrieren des Erreichens der definierten Höhe des Bohrgestänges mittels der Sicherheitseinrichtung,
• Steuern oder Regeln der Winde, um die Hebebewegung des Bohrgestänges abzubremsen, und
• fortgesetztes Anheben des Bohrgestänges um eine festgelegte oder festlegbare Strecke innerhalb des Sicherheitsabstands, d.h. oberhalb der definierten Höhe, durch Betätigen der Winde.

The method according to the invention is used to lift a drill rod attached to a drilling device, which at the upper end is attached to a boom of the drill guided traction means is suspended, the traction means being wound and unwound via a winch and thereby the drill rod can be raised and lowered, a safety device being arranged on the traction means by means of which the reaching of a defined height of the drill rod can be detected, and between the defined height and the gallows a safety distance is provided. The procedure consists of the following steps:

• Operating the winch to raise the drill pipe,
• Registering the reaching of the defined height of the drill pipe by means of the safety device,
• Controlling or regulating the winch to slow down the lifting movement of the drill string, and
• continued lifting of the drill pipe by a specified or specifiable distance within the safety distance, ie above the defined height, by operating the winch.

According to the invention, when the defined height of the drill rod is reached, the lifting process is not completely aborted, but after the lifting movement has been braked, the drill rod is raised beyond the defined height within the safety distance. As a result, the drill pipe can be lifted higher than in conventional systems in which the safety distance only serves as a "dead" buffer for the braking distance of the drill pipe, but is not available for targeted positioning of the drill pipe. As a result, the maximum possible height of the drill rod and thus the X dimension of the drill can be increased without any mechanical changes to the drill or drill rod having to be made. Furthermore, the invention enables the use of a longer drill rod and thereby the enlargement of the maximum drilling depth.

Advantageous embodiments of the invention emerge from the subclaims and the following description.

The step of controlling or regulating the winch in order to brake the lifting movement of the drill pipe can comprise a complete deceleration up to a standstill of the drill pipe, i.e. a complete stop of the winch. In this case, after the winch stop, the drill rod can be raised further by operating the winch. This can be done automatically or manually by an operator, for example, and in particular at a lower speed.

Alternatively, said step can be a braking of the lifting speed to a lower speed, taking into account certain measured and / or calculated data, which results in a smaller braking distance, the continued lifting now taking place at this lower speed. It is also conceivable that a dynamic control or regulation of the winch takes place, so that the continued lifting does not take place at a constant (lower) speed, but that the braking process is extended to virtually the entire additional defined or definable distance and the drill rods at the end of this distance comes to a standstill.

The additionally available distance can be set to a fixed value, which ideally is as close as possible to the position at which a collision with the boom occurs. As a result, the maximum additional height available due to the safety distance is optimally used. Alternatively, the value of the additional distance can be determined by the operator, the value of course not being allowed to exceed the safety distance.

In one embodiment it is provided that the braking and / or the continued lifting of the drill rod takes place taking into account the safety distance. The corresponding value can be stored, for example, in a control unit or controller or a memory to which the controller has access.

In a further embodiment it is provided that the developed traction element length is recorded by means of a traction element length detection device when the defined height of the drill rod is reached, the braking and / or the continued lifting of the drill rod taking into account this value of the developed traction element length when the defined height of the drill rod is reached . The measurement of the unwound traction device length is representative of a certain height of the drill string, whereby the absolute value of the height for a certain traction length does not have to be known / calibrated. For this purpose, the measured value of the traction device length when reaching the defined height can be saved or made known to a control and used as calibration so that the further values of the traction device length measured during continued lifting can be converted into a distance / height covered. The traction device length detection device can be arranged on or in the area of the winch.

In a further embodiment it is provided that when braking and / or continued lifting of the drill rod, the currently unwound traction device length is recorded by means of a traction device length detection device, the braking and / or continued lifting of the drill rod taking into account the currently unwound traction device length. The value of the current traction device length can be included in a control of the winch for braking the drill rod so that it comes to a standstill exactly at the end of the defined or definable route.

In a further embodiment it is provided that from the current traction device length and the traction device length when the defined height is reached, the current distance covered or lifted by the drill rod beyond the defined height is calculated and compared with the value of the safety distance, the braking and / or the continued lifting of the drill pipe is carried out taking into account the result of this comparison. This ensures that the winch is stopped in good time before the safety distance is reached and the lifting process of the drill pipe is ended so that no collision with the boom and thus damage can occur.

All of the parameters described above, i.e. the length of the traction device when the defined height is reached, the current length of the traction device, its conversion into a currently covered height (absolute or relative to the defined height) and / or the safety distance, can be displayed to the operator via a visualization device. Optical and / or acoustic warning signals can also be output if one or more of these values is reached, exceeded / fallen below or approached.

In a further embodiment it is provided that the lifting speed of the drill string is recorded by means of a speed measuring device and that when the defined height of the drill string is reached, the winch is controlled or regulated, taking into account the safety distance and the lifting speed, in such a way that the drill string is at the end of the definable or fixed Line comes to a standstill. The lifting speed of the drill rod can be recorded directly or indirectly by means of a speed measuring device, for example by means of a measuring arrangement which measures the unwinding or winding speed of the traction mechanism or the rotational speed of the winch. The lifting speed is preferably recorded when the defined height is reached or shortly before / after, in order to use this current speed value as a basis for calculating the braking effect of the drill rod or of the winch. For example, a braking distance can be calculated from the measured speed and this can be used as a basis for the control / regulation of the winch.

In a further embodiment it is provided that when the defined height of the drill rod is reached, the winch is stopped, with the continued lifting of the drill rod then taking place by the defined or definable distance within the safety distance by manual control of the operator. The operator can therefore, if necessary, according to the invention by the safety distance Use the additional height made available to position the drill rod, for example to insert longer support tubes or to open a drilling bucket. In other cases in which it is not necessary to raise the drill rod above the defined height specified by the safety device, a winch stop at the defined height takes place as in previous systems. Ideally, the operator can continue to raise the drill pipe any height within the safety distance.

In a further embodiment it is provided that the winch automatically stops during manual control, i.e. when manually controlled lifting takes place above the defined height, as soon as the drill rod reaches the end of the definable or defined route. This additional distance can maximally correspond to the safety distance, since otherwise a collision with the gallows would occur. It is preferably not possible for the operator to manually lift the drill rod beyond the safety distance.

In a further embodiment it is provided that the manually controlled lifting of the drill rod above the defined height takes place at a speed which is lower than a maximum lifting speed of the drill rod which can be achieved below the defined height. This reduces the braking distance of the drill rod and the safety distance can be optimally used for further lifting.

In a further embodiment it is provided that the winch is controlled / regulated by means of a control or control unit of the drilling device which is connected to the safety device and preferably has access to a memory unit in which the value of the safety distance is stored. The control system carries out all the calculations required for controlling or regulating the winch and can be connected to an input means, a visualization or output means and / or further actuators of the drilling device.

In a further embodiment it is provided that the safety device comprises a weight attached to the boom in the area of the traction mechanism and a counter element arranged on the traction mechanism and moved with it, the counter element contacting the weight when the defined height of the drill rod is reached and preferably sending a signal to the Control transmitted. A limit switch can be arranged on the boom. The counter-element lifts the limit switch weight on contact, which slackens the chains and activates the limit switch. The weight can be arranged next to the traction means or encompass or encompass it. The weight is preferably connected to the boom via one or more flexible fastening means such as ropes, wires or chains and hangs down therefrom. As a result, the weight can be moved or taken along by the counter element upwards in the direction of the gallows. The defined height of the drill pipe is determined by the height at which the weight is contacted by the counter-element (also referred to as the switching point). As an alternative to a version with limit switch, weight and counter element, the switching point can also be optically or otherwise contactless, for example.

Preferably, only a single safety device comprising a weight and a counterweight is provided. This means that ideally, the winch is controlled above the defined height during continued lifting exclusively on the basis of measured and / or stored values by the controller or by manual control of the winch, so that additional weights / switches in the sense of a multi-level safety device do not have to be used. This enables a simple and inexpensive construction of the safety device and is compatible with known rotary drilling machines.

In a further embodiment it is provided that when the drill rod continues to be raised above the defined height, that is, from the point in time at which the weight is contacted by the counter-element, the weight is lifted together with the drill rod. The counter element thus acts as a driver for the weight.

In a further embodiment it is provided that the traction means is attached to the drill rod via a swivel. The swivel enables the drill rod to be rotated about a vertical axis relative to the traction mechanism or the gallows. The counter-element is preferably arranged on or in the area of the swivel. The safety distance essentially corresponds to the distance between the swivel and the boom in the area of the traction mechanism. When using a weight and counter element as described above, the safety distance can be defined by the distance between the weight and the boom.

In a further embodiment it is provided that the drill rod is a Kelly bar. The drilling device is preferably a mobile drilling device with a mast or leader, at the upper end of which the gallows or Kelly gallows is arranged. The traction device is, in particular, a Kelly rope, which can be wound and unwound using a Kelly winch. A drilling tool is preferably arranged at the lower end of the Kelly bar, which can comprise several rods that can be displaced or telescopically mounted in one another. The drilling device is in particular a mobile rotary drilling rig and can comprise a casing machine.

The present invention further relates to a drilling device as described above, the drilling device having a control or control unit which is set up to carry out the method according to the invention in accordance with one or more of the embodiments described above. The controller is set up to receive and process signals from the safety device, an optionally provided traction device length detection device and / or an optionally provided speed measuring device. Furthermore, the controller has access in particular to a memory in which data such as the safety distance are stored. The control is set up to carry out calculations on the basis of the data transmitted by the various measuring devices and to operate and control the winch directly or indirectly on this basis.

Obviously, the same advantages and properties result as for the method according to the invention, which is why a repetitive description is dispensed with at this point. The above statements with regard to the possible configurations of the method according to the invention therefore apply accordingly.

Figur 1:

ein Ausführungsbeispiel des erfindungsgemäßen Bohrgeräts in einer Seitenansicht;

Figur 2:

einen Ausschnitt des Bohrgeräts gemäß Figur 1 im Bereich des Galgens in einer perspektivischen Ansicht;

Figur 3:

den Bereich gemäß Figur 2 in einer Seitenansicht;

Figur 4:

die Ansicht des Galgens gemäß Figur 2, wobei sich das Bohrgestänge in der definierten Höhe befindet;

Figur 5:

den Bereich gemäß Figur 4 in einer Seitenansicht;

Figur 6:

die Ansicht des Galgens gemäß Figur 2, wobei sich das Bohrgestänge am Ende des Sicherheitsabstands befindet;

Figur 7:

den Bereich gemäß Figur 6 in einer Seitenansicht; und

Figur 8:

das Bohrgerät gemäß Figur 1 beim Ausführen des erfindungsgemäßen Verfahrens, wobei sich das Bohrgestänge am Ende des Sicherheitsabstands befindet.

Further features, details and advantages of the invention emerge from the exemplary embodiments explained below with reference to the figures. Show it:

Figure 1:

an embodiment of the drilling device according to the invention in a side view;

Figure 2:

a section of the drill according to Figure 1 in the area of the gallows in a perspective view;

Figure 3:

the area according to Figure 2 in a side view;

Figure 4:

the view of the gallows according to Figure 2 , wherein the drill pipe is at the defined height;

Figure 5:

the area according to Figure 4 in a side view;

Figure 6:

the view of the gallows according to Figure 2 with the drill pipe at the end of the safety clearance;

Figure 7:

the area according to Figure 6 in a side view; and

Figure 8:

the drill according to Figure 1 when carrying out the method according to the invention, wherein the drill pipe is at the end of the safety distance.

In the Figure 1 an embodiment of the drilling device 1 according to the invention is shown in a side view, by means of which the method according to the invention can be carried out.

The drilling rig 1 is a mobile Kelly rotary drilling rig with a leader 4 mounted on a rotatable superstructure 2. At the upper end, the leader 4 has a mast head or Kelly boom 6 (hereinafter: gallows) over which a Kelly rope called a Kelly rope and by means of a Kelly winch 16 up and unwindable traction means 14 is guided. A drill rod 10 designed as a Kelly bar is attached to the Kelly rope 14 and can be raised or lowered essentially vertically along the leader 4 by actuating the Kelly winch 16. A carriage 8, which has a drill drive for driving the Kelly bar 10, is also displaceably mounted on the leader 4. A drilling tool 12 is arranged at the lower end of the Kelly bar 10, which comprises several rods that can be displaced or telescoped into one another. At the upper end, the Kelly bar 10 is attached to the Kelly rope via a twist catcher 18, so that the Kelly bar 10 can be set in a rotary movement around an essentially vertical axis relative to the Kelly rope 14 or to the leader 4 by means of the drill drive on the carriage 8.

the Figures 2 and 3 show an enlarged section of the drilling device 1 in the area of the boom 6 in a perspective and a side view. The Kelly rope 14 is guided over two pulleys of the gallows 6 and attached to the swivel 18 via a thimble 15. The swivel 18 is in turn attached to a so-called Kelly pot 19 at the upper end of the Kelly bar 10 and comprises several parts that can be rotated relative to one another.

In the area of the front deflection roller of the gallows 6, a frame 28 is arranged through which the Kelly rope 14 is passed and on which a weight 22 is suspended via two fastening means 26. The fastening means 26 can be, for example, chains, ropes, wires, connected rods, or a combination thereof. The weight 22 has a cylindrical shape and has a central passage / opening through which the Kelly rope 14 extends, that is to say engages around the weight 22 the Kelly rope 14 and hangs down from the gallows 6 to a certain height. In the area of the thimble 15 there is arranged a counter-element 24 which is moved along with the Kelly bar 10 and which is set up to interact with the weight 22 and to signal that the Kelly bar 10 has reached a defined height. Counter element 24 and weight 22 together with the limit switch form a safety device 20 to prevent damage to the drilling device 1 by lifting the Kelly bar 10 too high.

When the Kelly bar 10 is raised, the counter element 24 lifts the weight 22 at a certain height and the limit switch 24 sends a corresponding signal to a controller. This situation, in which the Kelly bar 10 has reached the defined height (the switching point) and the weight 22 is contacted by the limit switch 24, is in the Figures 4 and 5 shown, which have the same excerpts as the Figures 2 and 3 demonstrate. In known systems, the height of the weight 22, that is to say the switching point of the limit switch 24, defines the maximum height up to which the Kelly bar 10 can be raised. When the limit switch 24 was actuated, an immediate winch stop of the Kelly winch 16 was triggered and the lifting process of the Kelly bar 10 was ended. The height of the Kelly bar 10 at the switching point of the limit switch 24 is referred to here as the "defined height". For example, the height of the limit switch 24, the swivel 18 or the Kelly pot 19 at the switching point can serve as a reference point, but this is not relevant here.

In order to take into account the braking distance of the Kelly bar 10 and to prevent a collision with the boom 6 or the frame 28, the weight 22 is suspended at a certain safety distance from the frame 28, which is sufficiently large that even with a maximum braking distance at maximum Lifting speed of the Kelly bar 10 no collision with the gallows 6 takes place. In known systems, this safety distance could not be used for lifting the Kelly bar 10 and represented a “dead path”, as it were. The safety distance is essentially the distance between weight 22 and frame 28.

According to the invention, this safety distance can now be used for a further lifting of the Kelly bar 10. For this purpose, the controller evaluates the measured values of a traction device length detection device, which detects the currently unwound Kelly rope length, and also takes into account the value of the safety distance stored in a memory. In particular, the control is provided with the value of the Kelly rope length measurement at the switching point, ie when the defined height is reached. In the case of additional lifting, the weight 22, which is freely suspended and contacted from below by the limit switch 24, is lifted upwards in the direction of the frame 28. This situation is in the Figures 6 and 7 shown, in which it can be seen that the flexible fastening means 26 allow such additional lifting and move outward. The weight 22 is raised to just below the frame 28, so that the Kelly bar 10 has been raised by an additional distance which essentially corresponds to the safety distance.

With regard to the control / regulation of the winch, there are now several options for enabling the Kelly bar 10 to be raised beyond the defined height. On the one hand, it can be provided that when the defined height is reached - as before - a complete winch stop of the Kelly winch 16 takes place and the Kelly bar 10 comes to a standstill. Unlike before, however, the operator of the drilling device 1 now has the option of manually actuating / activating the Kelly winch 16 to raise the Kelly bar 10 further by a certain additional distance. This additional distance is less than or essentially the same as the safety distance and can either be stored as a fixed value in a memory or in the controller or can be specified by the operator within certain limits, for example entered via an input unit. The latter can mean that the operator can raise the Kelly bar 10 within a maximum value defined by the safety distance by any additional height above the defined height. Alternatively, the additional lifting can always take place up to a specified height. In particular, the Kelly bar 10 is raised above the defined height, taking current measurements of the Kelly rope length into account.

The maximum possible additional distance is preferably essentially the safety distance in order to have the greatest possible additional height available for lifting. It must of course be ensured here that the lifted weight 22 does not collide with the frame 28 and that a sufficient braking distance is taken into account for the braking of the Kelly bar 10 from the lifting movement during continued lifting. In order to keep this braking distance as short as possible and to have more distance available for targeted lifting, the lifting speed is reduced to a lower speed when the Kelly bar 10 is raised above the defined height.

Another possibility is that the control determines the braking effect that is required so that after the continued lifting of the swivel 18 at the end of the braking distance, ie the lifted weight 22 below the frame 28, comes to a standstill and the Kelly winch 16 above the defined Adjusts the height accordingly. An automatic regulation of the Kelly winch 16 takes place here in such a way that the Kelly bar 10 comes to a standstill above the defined height at the end of the additional section, whereby this is preferably essentially the safety distance. For this purpose, the control takes into account the unwound Kelly rope length and preferably the lifting speed of the Kelly bar 10 at the switching point. As a result, the controller can control or regulate the Kelly winch 16 and design the braking process in such a way that the weight 22 comes to a standstill just below the frame 28 (cf. Figures 6 and 7 ).

It can also be provided that the operator can choose between a manual mode, in which he can manually raise the Kelly bar 10 above the defined height as described above, and an automatic mode, in which an automatic control / regulation of the Kelly winch 16 above the defined height takes place, can choose.

There is preferably no further safety device or no further weight or a further limit switch between the weight 22 and the boom 6. It is therefore not possible to reach the definable or defined distance detected by a second safety device or weight limit switch arrangement, but the automatic or manual control / regulation of the Kelly winch 16 ensures that the Kelly bar 10 comes to a standstill in good time. Furthermore, a frame 28 does not necessarily have to be provided. It is therefore also conceivable that the weight 22 is suspended directly on the boom 6 or, for example, attached to the leader 4, as long as it is ensured that the weight 22 can be moved upwards from the normal position representing the defined height when it is raised further .

the Figure 8 shows the drilling device 1 according to the invention according to Figure 1 , the Kelly bar 10 being raised further beyond the defined height so that the weight 22 is just below the frame 28. Because the safety distance can now be used according to the invention for further lifting the Kelly bar 10, it is possible to measure the X dimension of the drilling device 1 (in the Figure 8 drawn in as reference character X) without a mechanical change in the drilling device having to take place. Furthermore, it is now possible to use a longer Kelly bar and thereby increase the maximum drilling depth.

List of reference symbols:

1

Drilling rig

2

Superstructure

4th

Broker

6th

gallows

8th

sleds

10

Drill rods (Kelly bar)

12th

Drilling tool

14th

Traction device (Kelly rope)

15th

Thimble

16

Winch (Kelly winch)

18th

Swivel

19th

Kelly pot

20th

Safety device

22nd

weight

24

Counter element (limit switch)

26th

Fasteners

28

frame

X

X dimension

Claims (15)

Method for lifting a drill rod (10) attached to a drilling device (1), the upper end of which is suspended from a pulling means (14) guided over a boom (6) of the drilling device (1), the pulling means (14) being via a winch (16) can be wound up and unwound and the drill rod (10) can thereby be raised and lowered, a safety device (20) being arranged on the traction means (14), by means of which the reaching of a defined height of the drill rod (10) can be detected, and wherein A safety distance is provided between the defined height and the boom (6), with the following steps: - operating the winch (16) to raise the drill pipe (10), - Registering the reaching of the defined height by means of the safety device (20), - Controlling or regulating the winch (16) in order to brake the lifting movement of the drill pipe (10), and - Continued raising of the drill pipe (10) by a specified or specifiable distance within the safety distance by operating the winch (16). Method according to Claim 1, characterized in that the braking and / or the continued lifting of the drill rod (10) takes place taking into account the safety distance. Method according to claim 1 or 2, characterized in that the unwound traction element length is detected by means of a traction element length detection device when the defined height of the drill rod (10) is reached, the braking and / or continued lifting of the drill rod (10) taking this value into account. Method according to one of the preceding claims, characterized in that when braking and / or continued lifting of the drill rod (10), the currently unwound traction device length is detected by means of a traction device length detection device, the braking and / or continued lifting of the drill rod (10) taking this into account Value takes place. Method according to claims 2 to 4, characterized in that from the current traction device length and the traction device length when the defined height is reached, the current distance of the drill rod (10) covered above the defined height is calculated and compared with the value of the safety distance, the Braking and / or the continued lifting of the drill rod (10) takes place taking this comparison into account. Method according to one of the preceding claims, characterized in that the lifting speed of the drill rod (10) is detected by means of a speed measuring device and that when the defined height of the drill rod (10) is reached, the winch (16) is controlled or controlled in this way, taking into account the safety distance and the lifting speed it is regulated that the drill pipe (10) comes to a standstill at the end of the definable or fixed route. Method according to one of claims 2 to 5, characterized in that when the defined height of the drill rod (10) is reached, the winch (16) is stopped, with the continued lifting of the drill rod (10) by the defined or definable distance by manual control of the operator. Method according to Claim 7, characterized in that the winch (16) automatically stops during manual control as soon as the drill rod (10) reaches the end of the definable or defined route. Method according to Claim 7 or 8, characterized in that the manually controlled lifting of the drill rod (10) above the defined height takes place at a speed which is lower than a maximum lifting speed of the drill rod (10). Method according to one of the preceding claims, characterized in that the control / regulation of the winch (16) takes place by means of a control of the drilling device (1) which is connected to the safety device (20) and preferably has access to a storage unit in which the value of the safety distance is stored. Method according to one of the preceding claims, characterized in that the safety device (20) has a weight (22) fastened to the boom (6) in the area of the traction means (14) and a counter-element (24) arranged on the traction means (14) and moved with it. comprises, wherein the counter element (24) contacts the weight (22) when the defined height is reached and preferably transmits a signal to the controller according to claim 10. A method according to claim 11, characterized in that as the drill rod (10) continues to be lifted, the weight (22) is lifted together with the drill rod (10). Method according to one of the preceding claims, characterized in that the traction means (14) is attached to the drill rod (10) via a swivel (18). Method according to one of the preceding claims, characterized in that the drill rod (10) is a Kelly rod. Drilling device (1) with a drill rod (10), which is suspended at the upper end on a pulling means (14) guided over a gallows (6), the pulling means (14) being wound up and unwound via a winch (16) and thereby the Drill rods (10) can be raised and lowered, a safety device (20) being arranged on the traction means (14), by means of which the reaching of a defined height of the drill rod (10) can be detected, with a Safety distance is provided, the drilling device (1) having a control which is connected to the safety device (20) and the winch (16),
characterized,
that the controller is set up to carry out the method according to one of the preceding claims.

Images