CABLE SWIVEL

Abstract

The invention relates to a cable swivel for connecting a cable or a retainer to a component, in particular a Kelly bar, which is rotatable relative to the cable or the retainer, with a stationary first swivel part which can be fastened on the cable or the retainer, and a rotatable second swivel part which is supported in a rotatable and axially fixed manner on the stationary first swivel part and can be connected to the component. Furthermore, in the case of the invention provision is made in that the rotatable second swivel part is of sleeve-shaped design with an axial passage and in that on the stationary first swivel part a connecting pin is designed which at least partially extends axially along the passage of the rotatable second swivel part.

Claims

1.-11. (canceled)

12. A cable swivel for connecting a cable or a retainer to a component, in particular a Kelly bar, which is rotatable relative to the cable or the retainer, with a stationary first swivel part which can be fastened on the cable or the retainer, and a rotatable second swivel part which is supported in a rotatable and axially fixed manner on the stationary first swivel part and can be connected to the component, wherein the rotatable second swivel part is of sleeve-shaped design with an axial passage and on the stationary first swivel part or the rotatable component a connecting pin is designed which at least partially extends axially along the passage of the rotatable second swivel part.

13. The cable swivel according to claim 12, wherein the connecting pin is of tubular design and running along its tube interior is a fluid line, a data line, an electric power line and/or a hydraulic line.

14. The cable swivel according to claim 12, wherein at the free end of the connecting pin a connecting section is designed to form a form-and/or force-locking connection to a counter connecting section.

15. The cable swivel according to claim 14, wherein the connecting section can be connected to a stator of a rotary feedthrough.

16. The cable swivel according to claim 12, wherein at its end facing away from the passage the connecting pin has a connector for a feed line.

17. A kelly bar arrangement with a cable swivel and a Kelly bar which is provided at its upper end with the cable swivel for suspension on a support cable and at its lower end with a connecting means for a tool, in particular a drilling tool, wherein the cable swivel is designed according to claim 12.

18. The kelly bar arrangement according to claim 17, wherein the Kelly bar is connected in a rotationally fixed manner to the rotatable second swivel part.

19. The kelly bar arrangement according to claim 17, wherein at its upper end the Kelly bar has a rotary feedthrough, which comprises a stator and a rotor that is connected in a rotationally fixed and axially fixed manner to the Kelly bar, and the stator of the rotary feedthrough is connected in a rotationally fixed and releasable manner to the connecting pin of the cable swivel.

20. The kelly bar arrangement according to claim 19, wherein to form a line connection a counter connecting section, which is designed to match the connecting section on the connecting pin, is arranged on the stator.

21. The kelly bar arrangement according to claim 20, wherein the line connection is designed as a releasable form- and/or force-locking connection to convey a fluid, data and/or electric power.

22. A drilling apparatus for drilling in the ground, with a carrier unit and a drill drive for rotationally driving a Kelly bar with a drilling tool, wherein a Kelly bar arrangement according to claim 17 is provided.

Description

[0021] The invention is described further hereinafter by way of a preferred embodiment illustrated schematically in the drawings, wherein show:

[0022] FIG. 1 a cross sectional view of a Kelly bar arrangement according to the invention with a cable swivel according to the invention prior to plugging together;

[0023] FIG. 2 a cross sectional view of a Kelly bar arrangement according to the invention with a cable swivel according to the invention in a plugged-together state;

[0024] FIG. 3 a perspective detailed view of a connecting pin before being connected;

[0025] FIG. 4 a perspective detailed view of a counter connecting section for the connecting pin for connection; and

[0026] FIG. 5 an illustration of the connecting pin of FIG. 2 after connection to the counter connecting section of FIG. 3.

[0027] A Kelly bar arrangement 10 with a Kelly bar 20 and a cable swivel 40 according to the invention is explained in greater detail in the following in conjunction with FIGS. 1 and 2. The Kelly bar 20 is designed as a telescopic Kelly bar 20 with a tubular outer Kelly bar 22 and a tubular inner Kelly bar 24 which is arranged therein in a rotationally fixed but axially displaceable manner relative to the outer Kelly bar 22. At the upper end of the inner Kelly bar 24, which protrudes from the outer Kelly bar 22, a tubular connecting region 26 for connection to a cable swivel 40 is arranged. The cable swivel 40 is connected to a non-depicted support cable, via which the Kelly bar 20 is retained. Inside the tubular connecting region 26 a rotary feedthrough 30 is attached to a non-depicted support plate.

[0028] For instance when used on a drilling apparatus the Kelly bar 20 is retained via the cable swivel 40 in a vertical alignment on a mast via the support cable, with the Kelly bar 20 being driven in a rotating manner by an annular rotary drive to carry out a Kelly drilling method. By means of an adaptor ring 28 on the outer Kelly bar 22 the Kelly bar 20 can be placed onto the rotary drive. The cable swivel 40 prevents in a generally known manner the rotation of the rotationally driven Kelly bar 20 from being transmitted to the drilling apparatus support cable rotationally fixed with respect to the said Kelly bar.

[0029] The cable swivel 40 according to the invention has a tubular first swivel part 41 with a sleeve body 42. At its upper end facing away from the Kelly bar 20 this first swivel part 41 is fastened in a known manner by a transversely directed retaining bolt 44 on a suspension of the support cable. Inside the sleeve body 42 a rotary bearing 48 is arranged, by way of which a tubular second swivel part 50 is supported in a rotatable but axially fixed manner inside the first swivel part 41. The second swivel part 50 has a tubular outer sleeve 52 which protrudes axially with respect to the first swivel part 41 in the direction of the component to be attached, i.e. the Kelly bar 20 in the illustrated embodiment. The protruding connecting end 53 of the second swivel part 50 thus formed can be plugged in so as to fit into the sleeve-shaped connecting region 26 of the Kelly bar 20, as illustrated graphically in FIG. 1. In the plugged-together state, which is shown in FIG. 2, the connecting end 53 of the cable swivel 40 is connected in an axially fixed and rotationally fixed manner via transversely directed connecting elements 18 to the Kelly bar 20.

[0030] Inside the tubular second swivel part 50 a passage 54 is designed, into which a tubular connecting pin 60 projects centrally. The connecting pin 60 has a tube body 62 with a tube interior 63. The tube body 62 is connected in a rotationally fixed manner to the first swivel part 41 and leads into a feed duct 46 in the first swivel part 41. At the free end of the connecting pin 60 which leads into the wider-diameter connecting end 53 of the outer sleeve 52 a connecting section 64 is designed which has an enlarged diameter with respect to the tube body 62, as illustrated graphically in FIG. 2.

[0031] Matching the connecting section 64 on the connecting pin 60 provision is made on the rotary feedthrough 30 on the Kelly bar 20 for a counter connecting section 36 that is also arranged centrally and depicted in greater detail in FIG. 3. The counter connecting section 36 is connected in a rotationally fixed manner to a stator of the rotary feedthrough 30. The stator is rotatable with respect to a rotor 32 of the rotary feedthrough 30, while the rotor 32 is connected in a rotationally fixed and axially fixed manner via a support plate 29 to the inner Kelly bar 24.

[0032] When the Kelly bar 20 and the cable swivel 40 are plugged together axially the counter connecting section 36 is moved axially into the sleeve-shaped connecting section 64 of the connecting pin 60. In doing so, a line connection is established between the connecting pin 60 and the rotary feedthrough 30. By way of a connector 66 at the rear end of the feed duct 46 it is thus possible to establish a line connection via the rotary feedthrough 30 to a line duct 25 in the interior of the Kelly bar 20. In FIG. 1 a part of the line inside the inner Kelly bar 24 is not illustrated. Through this it is possible to transmit e.g. fluid, in particular hydraulic fluid, and/or, by providing corresponding electric power or data lines, also electric power or data from outside to the Kelly bar 20 that rotates during operation and has a drilling tool attached at the lower end.

[0033] The plugging-together of the connecting section 64 on the connecting pin 60 with the counter connecting section 36 on the rotary feedthrough 30 is illustrated again in greater detail in FIGS. 3 to 5. At the free end of the tube body 62 of the connecting pin 60 a larger-diameter sleeve-shaped connecting section 64 is designed. At the free front side of the connecting section 64 two groove-like recesses 65 are introduced in the axial direction in order to form a rotationally fixed connection. Matching this, on an external side of the sleeve-shaped counter connecting section 36 two tongue-shaped webs 38 are designed which can be moved axially into the recesses corresponding thereto, whereby a rotationally fixed form-locking connection is formed.

[0034] To fasten the sleeve-shaped counter connecting section 36 on the rotary feedthrough 30 a connecting flange 37 is provided.