Drilling rig tongs system

Abstract

The invention relates to a drilling rig tongs system (10) having first and second tongs (12, 14), wherein: at least one of the tongs (12, 14) has two drive units (20, 22) acting in opposite directions and two movable clamping blocks (24, 26) each having a gripping surface (28); each of these clamping blocks (24, 26) is in engagement with a guide (30) of the respective tongs (12, 14) and can be moved along the guide (30) by means of the drive units (20, 22); and a straight line (42) intersects the region of the engagement of the respective clamping block (24, 26) with the guide (30) along a force introduction vector (42) which results during the connection or disconnection of two drill pipe elements (16) and starts from the gripping surface (28).

Description

[0001] Description

[0002] Drilling rigs gripper system

[0003] The invention relates to the technical field of drilling boreholes into hydrocarbon deposits for oil and gas exploration or for the development of geothermal energy. More specifically, the invention relates to a drilling rig gripper system, hereinafter sometimes referred to simply as a gripper system, which in technical terminology is sometimes called a "floorhand" or often also an "iron roughneck" and can also be called an automatic rod gripper or torque gripper. Such a gripper system is described in US Patent 2007 / 068669 A.

[0004] A clamping system of this type is used during the installation and removal of the drill string to connect or separate two drill string sections, in particular to connect a drill rod / section to the drill string or to detach a drill rod / section from the drill string (the terms drill rod and drill string section are synonymous). For such connection or detachment, the clamping system is usually moved by means of a movable arm or similar device to an area above the borehole or an area above the so-called mouse hole. There, a drill string section is connected to a stationary drill string section or a drill string section is detached from a stationary drill string section.The fixed drill string element is, for example, fixed in place as part of the drill string and / or by a fixing, for example, in the drill table, or due to its placement in the borehole and a fixing there. For the sake of readability—but without sacrificing broader general applicability—the following description continues using a drill string element fixed in place as part of the drill string and the use of the clamping system above the borehole. The description applies equally to a drill string element whose fixed position results from its placement in the borehole, and the use of the clamping system above the borehole should be implied whenever the use of the clamping system above the borehole is mentioned.In principle, a clamping system of the type proposed here can also be used at other points on a drilling rig and is generally suitable for any use in connecting or separating a threaded connection of two elements with a cross-section that is at least partially round.

[0005] The clamping system comprises, in a manner known per se, a first and a second clamp, namely a lower clamp (first clamp) and an upper clamp (second clamp) rotatable relative to the lower clamp. The lower clamp is used, in a manner known per se, to first fix the clamping system to the stationary drill string element. The upper clamp is then used – also in a manner known per se and utilizing its mobility relative to the lower clamp – either to connect another drill string element to the stationary drill string element by creating a threaded connection, or to detach a drill string element from the stationary drill string element by loosening / breaking the threaded connection.Each drill string element has, in a manner known per se, a threaded socket ("box") with an internal thread at one end and a threaded stud ("pin") with a corresponding external thread at the opposite end. Drill string elements with identical threaded sockets and studs can be detachably connected to one another by means of these threads – in a manner known per se. A pliers system of the type proposed here is designed and configured for making and breaking these threaded connections, and whenever, here and in the following, the connection or separation of two drill string elements, or simply connection or separation, is mentioned, this always means the joining of the respective threaded parts, the making of a respective threaded connection, the separation of the respective threaded parts, and the breaking of the respective threaded connection.

[0006] Each pair of pliers (upper and lower) also has – in a manner known per se – two opposing clamping blocks. These function essentially like the clamping / gripping jaws of a hand-operated pair of pliers and form the points of action of the upper and lower pliers. Each pair of pliers (upper and lower) grips the outer surface of a respective drill string element by means of the clamping blocks, namely by means of a gripping surface on the front side of each clamping block.

[0007] Such a clamping system must absorb enormous forces and therefore requires a corresponding design. A fundamental distinction is made between a clamping system based on a scissor principle and a clamping system with, in the broadest sense, C-shaped clamping bodies in or on which the clamping blocks are movable translationally and along a line. In the latter, the clamping blocks run in a tunnel guide. Both mechanisms (scissor principle, tunnel guide) have specific disadvantages. Due to the translational movement of the clamping blocks also provided for in this design, the innovation proposed here shares similarities with the tunnel guide, so that the consideration of the disadvantages of the latter is based on the prior art (e.g.,...).The mechanics known from the aforementioned US 2007 / 068669 A) are limited to the following: Each tunnel for guiding a clamping block must be designed to be sufficiently robust to absorb the expected torques, because high loads occur, especially at the edges of the tunnels, when a threaded connection is made or broken. The necessary robust design results in high material costs and a high overall weight for the clamping system. Hydraulic cylinders ("clamping cylinders") often serve as drive units for moving the clamping blocks. These are subjected to unfavorable constraint forces when a threaded connection is made or broken, which, for example, results in a reduced service life of the seals on the piston rod.

[0008] One object of the present invention is to provide a further embodiment of a pliers system (drilling rig pliers system), in particular an embodiment that enables material and weight savings.

[0009] This problem is solved according to the invention by means of a clamping system (drilling rig clamping system) with the features of claim 1. This clamping system is designed and configured for connecting (threaded connection as described above) a drill string element (first drill string element) to a stationary drill string element (second drill string element), or for separating (threaded connection as described above) a drill string element (first drill string element) from a stationary drill string element (second drill string element), or generally for connecting (threaded connection; see above) a first drill string element to a second drill string element, or for separating (threaded connection; see above) a first drill string element from a second drill string element. The drilling rig clamping system proposed here, often referred to simply as a clamping system, comprises a first clamping system and a second clamping system rotatable relative to the first clamping system.In technical terminology and also in the description presented here, the first and second pliers are referred to as lower pliers and upper pliers, respectively, and sometimes individually as pliers and together as pliers.

[0010] At least one of the jaws has two counter-rotating clamping blocks, each with its own drive unit for movement. This means that when clamping a drill string element, the jaw fulfills its gripping function by means of these clamping blocks and the drive units. The jaw has a guide, namely a linear guide, and each of these clamping blocks engages with the guide and is movable along the guide by means of the drive units. Each of these clamping blocks has a gripping surface.

[0011] The phrase "these pliers" refers to "at least one pair of pliers" and in the description presented here, "at least one pair of pliers" means the lower pliers or the upper pliers, whereby the phrase also implies that both pliers, i.e., the lower pliers and the upper pliers, have the characteristics mentioned for the "at least one pair of pliers".

[0012] The counter-rotating clamping blocks are each movable by means of a drive unit and can be moved during operation by means of each drive unit. With each drive unit, i.e., exactly two drive units, these act on each clamping block, and the drive units move the clamping blocks along the guide. Suitable drive units include two hydraulic cylinders or two hydraulic cylinder systems, or, more generally, any linearly acting drive system in pairs, for example, a rack and pinion drive / drive system, a pneumatic cylinder / system, a threaded spindle / threaded spindle system, etc. (linear drive).

[0013] The special feature of the clamping system proposed here lies, on the one hand, in the direction of force when clamping a drill string element by means of the clamping blocks, and on the other hand, in the torque transmission from the clamping blocks to the guide, namely from each of the clamping blocks to the guide or, if applicable, to its guide, when rotating the two clamps relative to each other.

[0014] Force is applied when clamping the drill string element (hereinafter referred to simply as a drill string element) to connect or detach it from the stationary drill string element. This occurs when, during the clamping process, the clamping blocks come into contact with the surface of the drill string element during the separation or connection of two drill string elements. The direction of force during clamping corresponds to the direction of action of the drive units. In the case of hydraulic cylinders acting as drive units, the force direction runs along the cylinder axes (axes of the hydraulic cylinders). The force is applied from the gripping surfaces of the clamping blocks, and this application can be illustrated by the force direction vectors emanating from them.These run axially to the direction of action of the drive units, for example, axially to the cylinder axes of the hydraulic cylinders, and when a drill string element is clamped, they run through its central longitudinal axis or at least substantially through its central longitudinal axis. The torque transmission from a clamping block to the guide occurs when, during the separation or connection of two drill string elements (first drill string element, second drill string element), a relative rotational movement takes place between a first drill string element, gripped by the clamping block – and the opposing clamping block of the same clamp – and a second drill string element, particularly when the threaded connection becomes tight during connection or when the still tight threaded connection is loosened ("broken") during separation.The torque transmission originates from the gripping surface of the respective clamping block and can be illustrated by a force application vector emanating from it. The force is applied when the drill string element rotates. The force application vectors are tangential to the cross-section of the gripped drill string element. The direction of the force application vectors corresponds to the direction of the force. With reference to these force application vectors, the special feature of the clamping system proposed here can be described by the fact that a straight line along each of the force application vectors resulting from the gripping surfaces of the clamping blocks when connecting or separating two drill string elements intersects the area of ​​engagement of the respective clamping block with the guide and also intersects the guide itself.

[0015] This, namely the straight line along each force application vector through the area where the respective clamping block engages with the guide, and through the guide itself, results in planar contact between the clamping block and the guide and a corresponding torque transmission, namely a uniform torque transmission over the entire area where the clamping block engages with the guide, i.e., a planar torque transmission. In contrast, with a conventional tunnel guide, a clamping block is essentially jammed within the tunnel. This leads to multiple linear contact points of the clamping block against the tunnel walls or the tunnel opening, to a corresponding load at these points, and in any case, to no planar torque transmission. With a tunnel guide, the gripping surface of the respective clamping block is necessarily located outside the tunnel when a threaded connection is made or broken.The force application vector originating from the gripping surface of the clamping block cannot intersect the tunnel acting as a guide at any point. Therefore, in a tunnel guide, the force application vector originating from the gripping surface always runs outside the guide (outside the tunnel) and never intersects it.

[0016] It is important to note that the description distinguishes between two different vectors and the terms force direction vector on the one hand and force application vector on the other. The force direction vectors pertain to the force application resulting from clamping and indicate the direction of this force application. Each force direction vector can also be referred to as the clamping force direction vector for even better differentiation. The force direction vectors point towards the central longitudinal axis of the respective drill string element, or at least substantially towards this central longitudinal axis. In other words, force application by means of the clamping blocks occurs in alignment with the central longitudinal axis of the drill string elements. The force application vectors pertain to the force application resulting from the rotation of the two clamps held by the clamping system relative to each other.Each force application vector can also be referred to as a rotational force application vector for even better differentiation. Each force application vector originates from the gripping surface of the respective clamping block and runs tangentially to the cross-section of the respective drill string element. A straight line along the force application vector intersects the area of ​​engagement of the respective clamping block with the guide and also intersects the guide itself.

[0017] Due to the surface-based torque transmission to the guide provided by the proposed clamping system, this system can be made significantly less massive and therefore considerably lighter compared to clamping systems with a tunnel guide. This saves material and thus costs. Furthermore, it simplifies the overall manufacturing process. The resulting lighter clamping system is also easier and more convenient to handle during operation.

[0018] As an alternative to referring to a force application vector resulting from operation, the clamping system proposed here can also be described with reference to geometric features: Each clamping block has a first thickness dl in the area of ​​its gripping surface and a larger second thickness d2 in the area of ​​its engagement with the guide. The geometry of the clamping block with these two thicknesses dl and d2 is further characterized by the following: A straight line extending from the gripping surface of the clamping block, i.e., a straight line extending from the clamping block in the area of ​​its first thickness dl, which intersects the guide with which the clamping block engages perpendicularly, runs in the area of ​​this intersection within the area of ​​the second thickness d2 of the clamping block. This describes how the areas with the two thicknesses dl and d2 are arranged relative to each other and means that the straight line, where it intersects the guide, runs within the material of the clamping block.This geometry also ensures the aforementioned area-wide moment transfer to the guide.

[0019] Advantageous embodiments of the proposed pliers system are the subject of the dependent claims. References within the claims indicate the further development of the subject matter of the referenced claim by the features of the respective dependent claim. They are not to be understood as a waiver of the right to obtain independent, substantive protection for the features or combinations of features of a dependent claim. Furthermore, with regard to the interpretation of the claims and the description, when specifying a feature in a dependent claim in more detail, it should be assumed that no such limitation exists in the preceding claim or any more general embodiment of the pliers system.Therefore, any reference in the description to aspects of dependent claims is to be read as a description of optional features, even without specific indication.

[0020] The guide, along which at least one clamping block is movable, is advantageously positioned parallel to, but off-center with respect to, the force exerted by the drive units of the respective clamping jaws. This placement (and orientation) parallel to the force avoids unnecessary lateral forces on the guide when clamping a drill string element using the clamping block. Off-center means that a straight line along the guide does not coincide with an imaginary force direction vector emanating from the respective drive unit when a clamping block is moved along the guide. The guide is, for example, attached to or integrally formed with a respective clamping jaw body, particularly on the outside of the jaw body. This allows sufficient clearance between the clamping blocks, whose gripping surfaces face each other, without unnecessarily restricting this clearance in the case of a different guide position.

[0021] In an advantageous embodiment, the guide is detachably connected to at least one of the pliers, for example, detachably attached to the outside of the pliers body. Despite the favorable torque transmission achieved in the pliers system proposed here, the guide remains a wear part. Such a detachable attachment of the guide allows for its replacement in case of wear, and if the guide is detachably attached to the outside of the pliers body, it is easily accessible for such replacement.

[0022] The patent claims filed with the application are formulation proposals without prejudice to obtaining further patent protection. Since the features of the dependent claims, in particular, may constitute independent inventions with regard to the prior art on the priority date, the applicant reserves the right to make these or further combinations of features, previously only disclosed in the description and / or drawings, the subject matter of independent claims or divisional declarations. These may also include independent inventions that exhibit a design independent of the subject matter of the respective referenced claims.

[0023] An embodiment of the proposed pliers system is explained in more detail below with reference to the drawing. Corresponding objects or elements are designated with the same reference numerals in all figures. This embodiment is not to be understood as a limitation of the invention. Rather, within the scope of the present disclosure, additions and modifications are entirely possible, in particular those which, for example, can be deduced by a person skilled in the art from the combination or modification of individual features or process steps in conjunction with those described in the general or specific descriptive section and contained in the claims and / or the drawing, with regard to solving the problem, and which, through combinable features, lead to a new object or to new process steps or sequences of process steps.

[0024] They show

[0025] Fig. 1 shows a clamping system for connecting a drill string element to a stationary drill string element or for separating a drill string element from a stationary drill string element.

[0026] Fig. 2 shows another view of the clamping system from Fig. 1.

[0027] Fig. 3 shows a section through part of the pliers system from Fig. 1.

[0028] Fig. 4 shows a pair of pliers from the pliers system shown in Fig. 1.

[0029] Fig. 5 shows a section of the illustration in Fig. 3.

[0030] Fig. 6 (Fig. 6a, Fig. 6b) Illustrations to demonstrate the torque transmission in the clamping system proposed here and

[0031] Fig. 7 (Fig. 7a, Fig. 7b) shows further illustrations to demonstrate the torque transmission in the clamping system proposed here. The illustration in Figure 1 shows an isometric view of an embodiment of a clamping system 10 proposed here (drilling rig clamping system 10).

[0032] The pliers system 10 comprises two pliers 12, 14 arranged in parallel planes and acting in parallel planes, which are also referred to as lower pliers 12 and upper pliers 14 for differentiation and according to their position. One of the pliers 12, 14 is rotatable relative to the other pliers 12, 14. For example, the upper pliers 14 is rotatable relative to the lower pliers 12, namely in its plane as well as in the plane parallel to the plane of the lower pliers 12.

[0033] The clamps 12 and 14 are each designed and configured for gripping ("clamping") a drill string element 16 (Fig. 3) and for creating or disconnecting a threaded connection between two drill string elements 16. The clamping system 10 as a whole is designed and configured for connecting a drill string element 16 to a stationary drill string element 16 or for disconnecting a drill string element 16 from a stationary drill string element 16. A drill string element 16 is stationary, for example, by being part of a drill string.

[0034] At least one pair of pliers 12, 14 is assigned two clamping blocks 24, 26 that are movable in opposite directions by means of at least one drive unit 20, 22. In the embodiment shown, this applies – in a fundamentally optional manner – to both pliers 12, 14, i.e., the lower pliers 12 and the upper pliers 14 are each assigned two clamping blocks 24, 26 that are movable in opposite directions by means of at least one drive unit 20, 22. In the embodiment shown, the situation is such that the at least one pair of pliers 12, 14 has two drive units 20, 22 acting in opposite directions, and that each clamping block 24, 26 is movable by means of one of these drive units 20, 22. This, too, is the case for both pliers 12, 14 in the embodiment shown – again, in a fundamentally optional manner.The lower jaw 12 and the upper jaw 14 each have two counter-rotating drive units 20, 22, and the clamping blocks 24, 26 assigned to the lower jaw 12 and the upper jaw 14, respectively, are movable by means of these drive units 20, 22. Each clamping block 24, 26 has a gripping surface 28. One gripping surface 28 is optionally profiled. The profile, or more generally the profiled gripping surface 28, is also referred to as a knife in technical terminology.

[0035] The following description continues based on the configuration shown, i.e., for clamping blocks 24, 26 movable by means of a drive unit 20, 22. Hydraulic cylinders, in particular one hydraulic cylinder for each clamping block 24, 26, serve as drive units 20, 22. The mobility of the clamping blocks 24, 26, or of a single clamping block 24, 26, for example with a plurality of hydraulic cylinders, is always implied and is a drive unit in the form of a hydraulic cylinder system.

[0036] The at least one pair of pliers 12, 14 has a guide 30, namely a linear guide, and each clamping block 24, 26 of the at least one pair of pliers 12, 14 is engaged with the guide 30 and movable along the guide 30 by means of the respective drive units 20, 22. This also applies to both pairs of pliers 12, 14 in the illustrated embodiment, i.e., each pair of pliers 12, 14 has a guide 30 whose clamping blocks 24, 26 are engaged with the respective guide 30 and movable along the respective guide 30 by means of the respective drive units 20, 22. Instead of exactly one guide (linear guide) for the two clamping blocks 24, 26 of at least one pair of pliers 12, 14 or exactly one guide for the two clamping blocks 24, 26 of each pair of pliers 12, 14, a guide that is split in a sense, i.e. a guide (linear guide) for each clamping block 24, 26 individually, is also possible.

[0037] For example, at least one guide rail acts as a guide 30, for example a guide rail on or in a top side of the respective pliers 12, 14, with a profile suitable for guiding, for example a T-profile or the like.

[0038] For engagement with the guide 30, namely for a positive-locking engagement with the guide 30 that allows movement along the guide 30, each clamping block 24, 26 movable along the guide 30 has a corresponding guide profile receptacle. By means of the guide profile receptacle, the respective clamping block 24, 26 is always engaged with a section of the guide 30.

[0039] Each pair of pliers has a pliers body 32, for example, a cast body functioning as a pliers body 32. In the embodiment shown, each pair of pliers 12, 14 has a pliers body 32 that is, in the broadest sense, C-shaped. The pliers body 32 carries or encompasses the guide 30. The clamping blocks 24, 26 of the respective pliers 12, 14 engage with the guide 30; that is, the pliers body 32 carries the clamping blocks 24, 26, so to speak, by means of the guide 30.

[0040] Within the scope of the description presented here, the term guide 30 includes, in particular, at least one corresponding profile on or in a top surface of the plier base body 32 of the respective plier 12, 14 (top surface guide), or at least one corresponding profile both on or in the top surface of the plier base body 32 of the respective plier 12, 14 and on or in a bottom surface of the same plier base body 32 opposite the top surface (double surface guide). Equally conceivable and having the same effect is a guide 30 which extends, with a suitable profile, for example, a T-profile, a dovetail profile, or the like, into the opening of the C-shaped plier base body 32 and between the two lateral legs of the O-shaped plier base body 32.

[0041] The drive units 20, 22 of the respective jaws 12, 14 are articulated to the ends of the jaw body 32 (each drive unit 20, 22 at one end). A feed element is movable, in particular extendable, by means of each drive unit 20, 22. For example, a hydraulic cylinder serves as the drive unit 20, 22, and a corresponding extendable piston rod 34 (Fig. 3, Fig. 4) serves as the feed element. The clamping blocks 24, 26 are articulated to the free end of each feed element, i.e., for example, to the free end of each piston rod 34. The points of the articulated connection are bolt points 36 of the jaw system 10.

[0042] Figure 2 shows the clamping system 10 from Figure 1 from a different perspective. It can be seen that a drive 38 is provided for the movement of the clamps 12 and 14 relative to each other. This drive engages the lower clamp 12 on one side and the upper clamp 14 on the other. In the embodiment shown, a hydraulic cylinder serves as the drive 38. Extending or retracting the piston rod of the hydraulic cylinder causes—in a manner known per se—a movement of the two clamps 12 and 14 relative to each other, namely a rotation of the upper clamp 14 relative to the lower clamp 12. Figure 3 shows a section through a part of the clamping system 10 from Figure 1, specifically a section in the area of ​​the engagement of one of the clamping blocks 24 and 26 with the guide 30. The sectional view clearly illustrates the double-sided guidance provided in the embodiment shown.The sectional view shows that the jaw body, acting as a guide 30, carries a guide rail on its upper surface and another guide rail on its opposite underside. Together, these two guide rails form the guide 30, with which the clamping block 24, 26 engages. For improved load transfer to the jaw body 32, but this is optional, the two guide rails are partially recessed into the material of the jaw body 32.

[0043] Figure 4 shows, in a simplified schematic form, one of the pliers 12, 14 of the pliers system 10 proposed here. The pliers 12, 14 shown in Figure 4 function, for example, as upper pliers 14. However, the statements apply equally to pliers 12, 14 designed as shown and functioning as lower pliers 12. The statements relating to Figure 4 apply in any case to at least one pliers 12, 14 of the pliers system 10.

[0044] In the schematically simplified representation in Figure 4, the C-shape of the plier body 32 – which is essentially optional – is particularly easy to recognize. The plier body 32 carries the guide 30, which is formed in one piece. The clamping blocks 24, 26 of the upper pliers 14 are engaged with the guide 30 and are movable along the guide 30; the clamping blocks 24, 26 are displaceable along the guide 30. During operation of the upper pliers 14, the movement of the clamping blocks 24, 26 along the guide 30 is effected by the counter-rotating drive units 20, 22 enclosed within it. These are articulated on one side to one of the ends of the C-shaped plier body 32 and on the other side to each of the clamping blocks 24, 26. Due to this double-sided linkage, the drive units 20, 22 also advantageously function as pendulum supports.A pendulum support transmits only compressive and tensile forces, and thus the advantage of this linkage is that only compressive and tensile forces act on the respective drive unit 20, 22, and no constraint forces, namely moments or lateral forces.

[0045] In the situation shown in Figure 4, the clamping blocks 24, 26 grip (clamp) a drill string element 16. The drill string element 16 is shown in section in Figure 4. The gripping surfaces 28 (Fig. 1) of the clamping blocks 24, 26 are in contact with the circular outer surface of the drill string element 16, at least by friction. A force is applied when the clamping blocks 24, 26 are brought together and when the drill string element 16 is clamped, originating from the gripping surfaces 28 of the clamping blocks 24, 26, and this force application can be illustrated by means of force direction vectors 40 emanating from them. These run axially to the direction of action of the drive units 20, 22, namely in the case of the hydraulic cylinders shown as examples as drive units 20, 22 axially to the cylinder axes, and point in the direction of the central longitudinal axis of the drill string element 16 or at least substantially in the direction of the central longitudinal axis of the drill string element 16.The described distribution of the force direction vectors 40 is the desired distribution for the application. The attachment of the hydraulic cylinders, shown as drive units 20, 22, to the gripper body 32 and the attachment of the clamping blocks 24, 26 to the respective drive units 20, 22 are chosen such that this desired distribution of the force direction vectors 40 results. In the illustrated embodiment, the cylinder axes of the hydraulic cylinders run coaxially with a line between the two bolt points 36 on the gripper body 32, and this line intersects the central longitudinal axis of the drill string element 16 or at least substantially intersects the central longitudinal axis of the drill string element 16.

[0046] In the case of, for example, rack and pinion drives as drive units 20, 22, the force direction vectors 40 run along the rack, and rack and pinion drives would be mounted on the jaw base 32 such that the force direction vectors 40 run coaxially with the line between the two bolt points 36 on the jaw base 32. In the case of, for example, lead screw drives as drive units 20, 22, the force direction vectors 40 run along the lead screw, and lead screw drives would be mounted on the jaw base 32 such that the force direction vectors 40 run coaxially with the line between the two bolt points 36 on the jaw base 32.

[0047] In the case of the hydraulic cylinders shown as examples of drive units 20 and 22, the special feature is that the cylinder axes are coaxial (or at least substantially coaxial) and point in the direction of the central longitudinal axis of the drill string element 16, or at least substantially in the direction of the central longitudinal axis of the drill string element 16. This applies accordingly to rack and pinion drives or lead screw drives when mounted as described above.

[0048] In the case of, for example, two, three or more hydraulic cylinders, pneumatic cylinders, rack and pinion drives or threaded spindle drives, and functioning as drive units 20, 22, the above applies accordingly to the respective resulting (sum) force direction vector 40.

[0049] Figure 5, in a simplified schematic representation, shows a section of Figure 4. It depicts the guide 30, one of the clamping blocks 24, 26, and the drill string element 16. Figure 5 illustrates an example situation in which the drill string element 16, gripped by the clamping block 24 (and the opposing clamping block 26), is rotated clockwise by the upper clamp 14, or such rotation is initiated. The resulting torque transmission can be illustrated by a force application vector 42. The force application vector 42 originates from the gripping surface 28 of the clamping block 24, runs tangentially to the cross-section of the gripped drill string element 16, and points in the direction of the force.The same applies to the clamping block 26 (not shown), except that the resulting force application vector 42 points in the opposite direction, i.e., directly towards the guide 30. A straight line 44 along the force application vector 42 intersects the area of ​​engagement of the respective clamping block 24 with the guide 30 and also intersects the guide 30 itself. This results in a planar contact between the clamping block 24 and the guide 30 and a corresponding torque transmission, namely a uniform torque transmission over the entire area in which the clamping block 24 is engaged with the guide 30, i.e., a planar torque transmission.

[0050] Figures 6a and 6b attempt to illustrate this in a different way. They show a large area representing the clamping block 24 and a small area representing the guide 30. The large and small areas are accordingly referred to as clamping block 24 and guide 30, respectively.

[0051] In the illustration in Figure 6a, a force originates from a lateral surface – in the case of the clamping block 24, this is its gripping surface 28 – and acts on the guide 30. The force is shown as the force application vector 42. The force lies entirely within the area where the clamping block 24 engages with the guide 30. Due to the force, the clamping block 24 is, in effect, pulled against the guide 30, as indicated by the majority of the arrows above and pointing towards the guide 30. This results in a large contact area of ​​the clamping block 24 with the guide 30 and a correspondingly large area of ​​torque transmission to the guide 30.

[0052] In the illustration in Figure 6b, a force, originating from the gripping surface 28 of the clamping block 24 and shown as the force application vector 42, acts on the guide 30. This force now lies outside the area where the clamping block 24 engages with the guide 30. As a result of this force, a torque is generated, causing the clamping block 24 to tilt against the guide 30, as shown—albeit exaggerated for illustrative purposes—by the dashed boundary lines of the clamping block 24. Here, unlike in Figure 6a, there is no longer a large-area contact with the guide 30 and a large-area torque transmission to the guide 30. Instead, there is a linear contact with a correspondingly unfavorable load on the material of the guide 30 and the clamping block 24 in the area of ​​this linear contact.Due to the planar torque transmission to the guide 30 in the proposed clamping system 10, the clamping system 10 can be made significantly less massive and therefore significantly lighter, not only compared to clamping systems with a tunnel guide, but also compared to a clamping system with a different geometry of the clamping blocks 24, 26 – namely, a geometry as shown in Figure 6b. This saves material and thus costs. Furthermore, the overall manufacturing process is simplified. The resulting lighter clamping system 10 is also easier and more convenient to handle during operation.

[0053] The illustration in Figure 7a serves to clarify the geometric features of the proposed clamping system 10. Each clamping block 24, 26 has a first thickness dl in the region of its gripping surface 28 and a larger second thickness d2 in the region of its engagement with the guide 30. The geometry of the clamping block 24, 26, which has these two thicknesses dl, d2, is further characterized by the following: A straight line 44 extending from the gripping surface 28 of the clamping block 24, 26, i.e., a straight line 44 extending from the clamping block 24, 26 in the region of its first thickness dl, which intersects the guide 30 with which the clamping block 24, 26 is engaged, runs in the region of this intersection in the region of the second thickness d2 of the clamping block 24, 26. This describes how the regions with the two thicknesses dl, d2 are arranged relative to each other and means that the straight line 44 where it intersects the guide 30, it runs within the material of the clamping block 24, 26.This geometry also ensures the previously mentioned planar torque transmission to the guide 30. In contrast, this is not the case with the geometry of the clamping block 24, 26 according to Figure 6b. This is shown in Figure 7b. There, the straight line 44 extending from the gripping surface 28 and intersecting the guide 30 perpendicularly is clearly outside the material of the clamping block 24, 26 in the area of ​​this section.

[0054] The most important aspects of the description submitted here can be summarized as follows: A drilling rig clamping system 10 is described, comprising a first and second clamp 12, 14, wherein at least one clamp 12, 14 has two counter-rotating drive units 20, 22 and two movable clamping blocks 24, 26, each with a gripping surface 28, wherein each of these clamping blocks 24, 26 is engaged with a guide 30 of the respective clamp 12, 14 and is movable along the guide 30 by means of the drive units 20, 22, and wherein a straight line 44 along a force application vector 42 resulting from the gripping surface 28 when connecting or separating two drill string elements 16 intersects the area of ​​engagement of the respective clamping block 24, 26 with the guide 30.

[0055] Although the invention has been illustrated and described in detail by the exemplary embodiment, the invention is not limited by the disclosed example, and other variations can be derived from it by a person skilled in the art without departing from the scope of protection of the invention. List of reference numerals

[0056] 10-jaw system, drilling rig jaw system

[0057] 12 Pliers, lower pliers

[0058] 14 Pliers, upper pliers

[0059] 16 drill string elements

[0060] 18 (free)

[0061] 20, 22 Drive unit

[0062] 24, 26 terminal block

[0063] 28 Grip surface (of a clamping block)

[0064] 30 Guided Tour

[0065] 32 pliers bodies (of one pair of pliers)

[0066] 34 Piston rod (of a drive unit)

[0067] 36 Bolzpunkt

[0068] 38 Drive

[0069] 40 Force direction vector

[0070] 42 Force application vector

[0071] 44 Straight line (along the force application vector)

Claims

Patent claims 1. Drilling rig clamping system (10) for connecting a drill string element (16) to a stationary drill string element (16) or for separating a drill string element from a stationary drill string element (16), comprising a first clamp (12) – lower clamp (12) – and a second clamp (14) – upper clamp (14) rotatable relative to the lower clamp (12), wherein at least one clamp (12, 14) is assigned two counter-rotating clamping blocks (24, 26), each clamping block (24, 26) having a gripping surface (28), the at least one clamp (12, 14) having a guide (30), and each clamping block (24, 26) of the at least one clamp (12, 14) being engaged with the guide (30) and being movable along the guide (30), characterized in that a straight line (44) extends along a path during the connecting or Separating two drill string elements (16) results in a force application vector (42) emanating from the gripping surface (28) in the area of ​​engagement of the respective clamping block (24,26) with the guide (30) and the guide (30) itself, and that when a drill string element (16) is clamped, the resulting force direction vectors (40) point in the direction of a central longitudinal axis of the drill string element (16) or at least substantially towards this central longitudinal axis.

2. Drilling rig clamping system (10) according to claim 1, wherein each clamping block (24, 26) has a first thickness dl in the area of ​​its gripping surface (28) and a larger second thickness d2 in the area of ​​its engagement with the guide (30) and wherein the force application vector (42) resulting from joining or separating cuts the clamping block (24, 26) in the area of ​​the larger second thickness d2.

3. Drilling rig clamping system (10) according to claim 1 or 2 and with at least one drive unit (20, 22) for moving the clamping blocks (24, 26) and with a position of the guide (30) off-center and parallel to a force effect of the at least one drive unit (20, 22) .

4. Drilling rig gripper system (10) according to claim 1, 2 or 3 and with a position of the guide (30) outside on a gripper base body (32) of the at least one gripper (12, 14) .

5. Drilling rig clamping system (10) according to one of the preceding claims, wherein the at least one clamp (12, 14) comprises at least two counter-acting drive units (20, 22) and each clamping block (24, 26) of the at least one clamp (12, 14) is movable along the guide (30) by means of at least one drive unit (20, 22).

6. Drilling rig gripper system (10) according to claim 5, with hydraulic cylinders as counter-acting drive units (20, 22) with cylinder axes pointing towards a central longitudinal axis of the drill string element (16) or at least substantially towards this central longitudinal axis. I. Drilling rig gripper system (10) according to one of the preceding claims, wherein the at least one gripper (12, 14) comprises a C-shaped gripper body (32), wherein one of the drive units (20, 22) is articulated to each end of the gripper body (32), wherein a piston rod (34) is movable, in particular extendable, by means of each drive unit (20, 22) and wherein one of the clamping blocks (24, 26) is articulated to each free end of each piston rod (34).

8. Drilling rig gripper system (10) according to one of the preceding claims, wherein the guide (30) is detachably connected to the at least one gripper (12, 14).

9. Drilling rig gripper system (10) according to claims 7 and 8, wherein the guide (30) is detachably connected to the gripper body (32) of the at least one gripper (12, 14).

10. Drilling rig gripper system (10) according to one of the preceding claims, wherein a linear guide acts as the guide (30). II. Drilling rig with a drilling rig gripper system (10) according to one of the preceding claims.

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