DE9005954U1 - Connection for drill pipes or similar - Google Patents

Abstract

In a detachable connection for drill pipes and other objects which can be used in the sinking of boreholes, a sleeve part (21) has in the interior radially directed projections, the undersides of which at least partly form engagement surfaces for bearing surfaces on an insertion part (11) for transmitting axial tensile forces. The insertion part (11) is provided on the outside with radially directed locking pieces which in each case form the bearing surfaces with at least part of their front sides. At least one supporting surface for seating the insertion part (11) for transmitting axial compressive forces is located on the sleeve part (21). Furthermore, there are push-in parts via which a torque can be transmitted. <IMAGE>

Description

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The invention relates to - ,.the legible connection with socket part and insert part for drill pipes or other objects that can be inserted when drilling holes, in which an axial force and torque transmission is provided via shaped elements that are engaged in the operating state of the connection.

In a known threadless coupling of drill rod parts (DE-PS 947 782), the socket part has a blind hole with a smooth wall into which a cylindrical pin protruding from the plug-in part can be inserted. In addition, the plug-in part has two diametrically opposed There are cams that can enter into recesses at the end of the socket part when the coupling is assembled. A torque can then be transmitted via these. The pin of the plug-in part has an annular groove near its end into which hemispherical bolts can engage after the parts have been assembled. These bolts are screwed into radial holes in the socket part. Tensile forces can only be absorbed to a very small extent, if at all, by the screws. The plug-in part and the socket part both have a closed cross-section. There is no internal axial passageway in such a coupling.

In another known rod coupling (DE-AS 12 29 932) the socket part is hexagonal on the inside. The plug-in part has a pin with a corresponding external hexagon, which should fit into the socket part with sufficient clearance. The pin has an annular groove between its ends. In the socket part there are two parallel holes into which a U-shaped bracket can be inserted, the legs of which engage in the pin groove of the pin at opposite points when the plug-in part is inserted into the socket part up to a stop. This is simply a matter of securing the parts against axial relative movement and preventing them from separating.

The object of the invention is to create a threadless, detachable connection of the type specified, which not only allows torque to be transmitted in both directions, but also allows full transmission of axial compressive and tensile forces, and which also makes a large internal passage available in the parts to be connected. The invention also aims at advantageous designs of the connection or its parts in detail. The problems associated with all this, which the invention deals with, emerge from the respective explanation of the solution presented.

The invention is characterized by the features specified in claim 1.

This creates a connection for drill pipes or other parts that can be used to drill holes, in particular so-called displacement screws and similar tools, which is characterized by a number of significant advantages. The connection is made by simple relative

movements of both parts can be created easily and quickly. It allows the transmission of axial pressure and tensile forces as well as the transmission of torque in both directions. The connection is designed in such a way that it can be designed to absorb high loads without difficulty. All of this is achieved without blocking the interior of the parts. Rather, there is a free internal passage, so that the connection is particularly suitable and advantageous in cases in which a drill string, a tool or an aggregate used in drilling work is to be flowed through by a medium. This can be, for example, drilling fluid or concrete that is to be fed to the bottom of a borehole, such as in pile foundations.

The design can be such that the plug-in part has radially protruding projections with torque transmission surfaces distributed over its outer circumference, with counter surfaces inside the socket part assigned to them. There are various options for the design and arrangement of such counter surfaces. For example, the projections inside the socket part can be designed like strips and their sides form the counter surfaces. In another design, in addition to the projections, radially protruding parts are arranged inside the socket part, distributed over the inner circumference, with their sides forming the counter surfaces for the torque transmission surfaces of the plug-in part.

Furthermore, there are various options for the design and arrangement of the insert parts. They can have the form of longitudinal bars that can be inserted into recesses on the outer circumference of the insert part and into passages in the socket part. The number of these longitudinal bars can be varied according to requirements, in particular depending on the size of the torque that they have to transmit.

is to be selected. In the case of applications in which essentially only a small torque is to be transmitted in one direction, an arrangement of two longitudinal bars can be sufficient and appropriate, particularly at diametrically opposite locations. The longitudinal bars can advantageously be releasably secured to the plug-in part, e.g. by means of clamping pins or the like.

In another design, pins are provided as insertion parts on the outer circumference of the insertion part, which can be inserted into recesses on the outer circumference of the socket part. The design can be such that the pins are guided so that they can move over a limited distance and are under the force of compression springs.

The connection is particularly suitable for double-walled parts, where in addition to a central cavity, there is an annular cavity that is closed off from it. An inner pipe then extends into the socket part and the plug-in part. When the connection is joined, the ends of the pipes lie against one another, either bluntly or with a certain overlap, whereby at least one seal is advantageously present.

Further details, features and advantages of the invention emerge from the following explanation of embodiments, from the associated drawings and from the claims. They show:

Fig. 1 an embodiment of a plug-in part partly in view, partly in longitudinal section,

Fig. 2 is a front view of Figure 1,

Fig. 3 shows a version of a socket part in longitudinal section that matches the plug-in part according to Figures 1 and 2,

Fig. 4 is a front view of Fig. 3,

Fig. 5 a unit of a drill pipe (drill rod part) , in the area of the ends partly in section,

Fig. 6 a connection between a drill pipe and a displacement screw, partly in section,

Fig. 7 an insert part of a different design, partly in view, partly in section,

Fig. 8 a socket part of a different design, partly in elevation, partly in section,

Fig. 9 the assembled connection with the parts according to Figures 7 and 8, partly in view, partly in section,

Fig. 10 is a section along the line X-X in Fig. 9,

Fig. 11 another embodiment of a plug-in part, partly in elevation, partly in section,

Fig. 12 another embodiment of a socket part, partly in view, partly in section,

Fig. 13 the assembled connection with the parts according to Figures 11 and 12, partly in view, partly in section and

Fig. 14 shows a process for releasing the connection according to Figure 13.

Figures 1 to 4 show an advantageous embodiment of the connection with plug-in part 11 and socket part 21. Both parts each have a free axial passage D of relatively large diameter, which can continue into the adjoining part ¹ , e.g. drill pipe, tool or the like. The socket part 21 is provided on the inside of its wall with projections 22 which are regularly distributed over the circumference and run in the direction of the surface lines, between which corresponding passages 23 remain. The undersides of the projections 22 form flat contact surfaces for contact surfaces 14 provided on the plug-in part 11.

These contact surfaces 14 are formed by the front sides of locking pieces 13, which are regularly distributed over the outer circumference of the plug-in part 11 and are directed radially. The extension a. of the locking pieces 13 in the circumferential direction is slightly less than the circumferential dimension b of the openings 23 in the socket part 21.

In this embodiment, the socket part 21 has a support surface 25 on the front side, against which a support 15 on the plug-in part 11 can come to rest when the connection is made.

In addition to the locking pieces 13, radially projecting lugs 12 are provided on the plug-in part 11, which are expediently distributed in a regular arrangement over the outer circumference of the plug-in part 11, and advantageously so that their number is equal to the number of locking pieces 13. In principle, the lugs 12 can merge directly into the locking pieces 13. However, it is advantageous to leave a gap between the two, as can be seen from Figure 1.

A side surface 17 of the lugs 12 is aligned with a side surface 18 of the locking pieces 13. The other side surfaces 16 of the lugs 12 serve as torque transmission surfaces when the connection is assembled. They then come into contact with counter surfaces 26 inside the sleeve part 21, which in the embodiment shown are formed by side surfaces of the projections 22.

The connection also includes elements known as insert parts, which, after the socket part 21 and the insert part 11 have been joined together, are in positive engagement with them and run parallel to the longitudinal center axis of the connection. The arrangement and design is such that a torque can be transmitted via the insert parts. There are various options for the individual design.

For the embodiment shown in Figures 1 to 4 and also in Figures 5 and 6, the following are used as input

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As sliding parts, longitudinal bars 31 can advantageously be considered, which can be inserted into recesses 19 on the outer circumference of the insertion part 11 and into free passages 23 at the relevant points of the socket part 21. The insertion part 11 is designed in such a way that the longitudinal bars 'I can be pushed in the direction of the socket lines into the recesses 19 and the passages 23 aligned therewith.

Figure 5 shows a drill pipe 1 which is designed at one end as a socket part 21 and at the other end as an insert part 11. Any number of such drill pipes can then be joined together to form a string by means of the connecting parts explained.

In Figure 6, a drill string part 2 is connected to a displacement screw 3 by means of the connection, whereby this is shown in the assembled state, on one side in view, on the other side in section.

The connection is made in the embodiment described as follows. The plug-in part 11 is inserted axially into the socket part 21 in such a way that the locking pieces 13 and also the projections 12 can be pushed through the openings 23. The length of the openings 23 and the locations where the sealing pieces 13 are located are coordinated with one another in such a way that the locking pieces 13 can emerge from the inner end of the openings 23 before the support 15 on the plug-in part 11 comes into full contact with the support surface 25 of the socket part 21. The plug-in part 11 is then rotated about its axis relative to the socket part 21 in such a way that the contact surfaces 14 on the locking pieces 13 slide under the ends of the projections 22 and thus come into contact with the engagement surfaces 14. In addition, the torque transmission surfaces 116 on the lugs 12 of the

Insert part 11 for contact with the counter surfaces 26 of the projections 23 of the socket part 21. In this state of connection, the surfaces 14 and 24 can transmit an axial tensile force and the surfaces 15 and 25 an axial compressive force between the interconnected parts. In addition, the transmission of a torque in one direction of rotation is possible via the surfaces 16 and 26. A torque transmission in the other direction of rotation is ensured by the longitudinal bars 30 (Figure 5), which are introduced into the recesses 1.9 and the passages 23 aligned with them. The longitudinal bars 30 can each be secured by a split pin or similar pin, as is shown at point 32.

Figures 7 to 9 show another version of the connection which differs from that shown in Figures 1 to 4 in some details, but for which what has been said there also applies in principle. One difference is that Figures 1 to 6 show a drill pipe or similar rod assembly with a single passage D. The version shown in Figures 7 to 9 shows the use of the connection with a so-called double-wall rod assembly. Both the plug-in part 41 and the socket part 51 have a large inner passage D1 and an annular passage D2 surrounding it, which is created by inserting an inner pipe 7 or 8 into an outer pipe 5 or 6. When the connection is put together, a bell-shaped end 7a of the inner pipe 7 engages over the end of the inner pipe 8, with a seal ^1J additionally ensuring that the two spaces D1 and D2 remain separate from one another.

In this embodiment, the insert part 41 also has radially projecting lugs 42 and mirror pieces 43, the extent of which in the circumferential direction is the same here

size. A side surface 47 of the lugs 42 is aligned with a side surface 48 of the locking pieces 43. The other side surfaces 46 of the lugs 42 serve as torque transmission surfaces.

Inside the socket part 51, projections 52 and radially projecting parts 57 are provided. Side surfaces 56 of the latter form the counter surfaces for the torque transmission surfaces 46 of the plug-in part 41. Between the projections 52 and the parts there are passages 53 through which the lugs 42 and locking pieces 43 can move when the plug-in part 41 is inserted into the socket part 51. When both parts are subsequently rotated relative to one another, the locking pieces 43 engage with their contact surfaces 44 under the projections 52 and rest against the engaging surfaces 54 formed by their undersides, which ensures perfect tensile force transmission.

In the assembled state of the connection, which is shown in Figures 9 and 10, the plug-in part 41 rests with a shoulder-like support 45 on a support surface 55 of the socket part 51, so that the transmission of compressive forces is also ensured.

Similar to the design according to Figures 1 to 6, here too there are longitudinal bars 31 as additional torque-transmitting elements, which can be inserted into recesses 49 on the outer circumference of the plug-in part 41 and into free areas of the passages 53 in the socket part 51 that are aligned with the recesses. Only one such longitudinal bar 31 is shown in Figure 7. Advantageously, at least two longitudinal bars are provided at opposite locations. Their number can also be greater depending on the requirements.

In the embodiment according to Figures 11 to 13, the sleeve part 71 again has inner projections 72 distributed over the circumference with passages 73 between them. On the plug-in part 61 there are radially projecting locking pieces 63 which, when the parts are joined together, move through the openings 73 on the socket part 71 and, after relative compression of the part, ^move under the tension ^spring 72. The contact surfaces 64 come into contact with the rear contact surfaces 74 of the projections 72. This ensures perfect tensile force transmission. Compressive forces are transferred from the support 65 of the plug-in part 61 to the support surface 75 of the socket part 71. In addition, a shoulder 66 on the plug-in part 61 can also rest on the front sides 76 of the projections 72.

In order to transmit torque in both directions, this design uses insert parts in the form of pins 67 on the insert part 61, which can engage in through holes 77 on the socket part 71, as can be seen in Fig. 13. The number of pins can be selected according to the loads. The pins 67 can be moved in guide holes and are under the force of compression springs 68. The extension path is limited by a collar 69 on the pin 67. When joining the plug-in part 61 and the socket part 71 by pushing them together, the pins 67 first sit on the support surface 75 of the socket part 71. They then slide along this during the subsequent relative rotation of the two parts until, at the end of this movement, they snap into the holes 77 arranged at the corresponding locations.

When the connection is released, the pins 67 are pushed back against the force of the compression springs 68 so far that the insertion part 61 can be rotated relative to the socket part 71 by the required angle around its axis, whereby

the ends of the pins 67 slide on the support surface 75. The parts are then moved axially apart, whereby the connection is separated. A counterholder 78 with projections 79 that fit into the holes 77 can be used to push back the pins 67. The counterholder is in particular ring-shaped, as shown in Fig. 14, so that it can be moved on the cylindrical outside of the sleeve part 71. It can be designed in a split manner so that it can be placed around the sleeve part for use.

In the embodiment according to Figures 11 to 13, the plug-in part 61 also has an inner tube 7 and the socket part 71 has an inner tube 8, so that two passages D1 and D2 are present, as can be the case with a double rod.

All features mentioned in the above description or shown in the drawings are to be considered as falling within the scope of the invention, either individually or in combination, as far as the known state of the art permits.

Claims (9)

Wirth Maschinen- und Bohrgeräte-Fabrik GmbH in D-5140 Erkelenz Protection claims 1. Detachable connection with socket part and plug-in part for drill pipes or other objects that can be used when drilling holes, in which axial force and torque transmission is provided via shaped elements that are engaged in the operating state of the connection, characterized by the following features: the socket part (21, 51, 71) has a free axial passage (D, Dl) and, distributed over the inner circumference of its wall, radially directed projections (22, 52, 72), between which axial passages (23, 53, 73) are present, the undersides of at least some of the projections (22, 52, 72) form contact surfaces (24, 54, 74) for contact surfaces (14, 44, 64) on the plug-in part (11, 41, 61) for transmitting axial tensile forces, the plug-in part (11, 41, 61) has a free axial passage (D, D1) and, distributed over its outer circumference, radially directed locking pieces (13, 43, 63), the extent (a) of which in the circumferential direction is slightly less than the circumferential dimension (b) of the passages (23, 53, 73) in the socket part (21, 51, 71) and which each have at least one part of their front sides which are the attack surfaces · ■ ■ · · (24, 54, 74) of the projections (22, 52, 72) of the sleeve part (21, 51, 71) form associated contact surfaces (14. 44, 64), the sleeve part (21, 51, 71) has at least one support surface (25, 55, 75) for a support (15, 45, 65) of the plug-in part (11, 41, 61) for transmitting axial pressure forces, eg insert parts (31; 67) are provided which, after the sleeve part (21, 51, 71) and plug-in part (11, 41, 61) have been joined together, are in positive engagement with them and run parallel to the longitudinal center axis of the connection, such that a torque can be transmitted via them. 2. Connection according to claim 1, characterized in that radially projecting projections (12, 42) with torque transmission surfaces (16, 46) are provided on the plug-in part (11, 41), distributed over its outer circumference, to which counter surfaces (26, 56) are assigned in the interior of the sleeve part 21, 51(). 3. Connection according to claim 2, characterized in that the projections (22) inside the sleeve part (21) are designed like strips and form with their sides the counter surfaces (26) for the torque transmission surfaces (16) of the plug-in part (). 4. Connection according to claim 2, characterized in that in the interior of the sleeve part (51), in addition to the projections (52), radially projecting parts (57) are arranged distributed over the inner circumference, which form with their sides the counter surfaces (56) for the torque transmission surfaces (46) of the plug-in part (41). 5. Connection according to one of claims 1 to 4, characterized in that longitudinal bars (31) are provided as insertion parts, which are inserted into recesses (49) on the outer circumference of the insertion part (11, 41) and into passages (23, 53) of the sleeve part (21, 51). 6. Connection according to claim 5, characterized in that the longitudinal bars (31) can be releasably secured to the plug-in part (11, 41). 7. Connection according to one of claims 1 to 4, characterized in that pins (67) are provided as insertion parts on the outer circumference of the insertion part (61), which can be inserted into bores (77) or the like on the outer circumference of the socket part (71). 8. Connection according to claim 7, characterized in that the pins (67) are guided so as to be displaceable with a limited height and are under the force of compression springs (68). 9. Connection according to one of claims 1 to 8, characterized in that an inner tube (7 or 8) extends into the socket part (51, 71) and into the plug-in part (41, 61) and that the inner tubes (7, 8) are tightly connected to one another in the operating state of the connection.