WO2000052296A1

WO2000052296A1 - Swivel device

Info

Publication number: WO2000052296A1
Application number: PCT/GB2000/000672
Authority: WO
Inventors: Paul Bernard Lee
Original assignee: Orr, William, Mclean
Priority date: 1999-03-03
Filing date: 2000-03-03
Publication date: 2000-09-08
Also published as: AU2923200A; GB9904763D0

Abstract

A swivel device for use with a casing circulator in the exploitation of hydrocarbon reserves comprises an elongate housing (1) attachable at its upper end to a rigid portion on a derrick (not shown), and an elongate swivel means (8) having an upper end (4) rotatably mounted in the elongate housing (1) so as to provide precessional and pendular freedom to the lower end of said elongate swivel means, wherein said elongate swivel means is attachable at its lower end (2) to a casing circulator.

Description

SWIVEL DEVICE

The present invention relates to a swivel device for use with a casing circulator in the exploitation of hydrocardon reserves.

During casing running operations devices are commonly used to circulate the conduit (casing) into the hole. Fully automatic, packer-type casing filling and circulating tools are known for this purpose. These may be operated from the drilling console m order to save time m filling and circulating operations whilst improving safety.

One such device is a hydro-mechanical casing circulator which is designed to work in conjunction with top drive drilling packages. This device allows operators to fill the casing whilst running each joint. When it is necessary to circulate the casing into the hole, the device may be activated on-the-fly by increasing pump pressure above 1500 psi. Whilst the ability to control all of the device functions at the drilling console generally means increased efficiency and safer operation, these circulating devices are disadvantageous m the sense that they must be lowered onto the casing or stabbed into the casing. On most rigs, the device is threaded to a rigid component ±e the top drive that runs on tracks up and down the derrick. Frequently the rigid top drive does not align with the casing and the circulating devices are therefore difficult to centre m or around the casing during casing running operations. In addition, misalignment is a problem in floating rigs where the casing run into the well is rigid, but the rig is constantly moving. The present invention seeks to improve the safety and efficiency of casing running operations by enhancing the flexibility of casing circulators.

According to the invention there is provided a swivel device for use with a casing circulator m order to exploit hydrocarbon reserves, said device comprising: an elongate housing attachable at its upper end to a rigid portion on a derrick; and, elongate swivel means having an upper end rotatably mounted in said housing so as to provide precessional and pendular freedom to the lower end of said swivel means, wherein said swivel means is attachable at its lower end to a casing circulator.

The device of the invention allows the user to manipulate an attached casing circulator by hand into or around the casing. This makes it possible to induce circulation irrespective of whether the rig is in motion or of any misalignment of the rigid top drive with the casing.

The device of the invention preferably allows complete lie 360°) precessional freedom of the swivel means at its lower end. Preferably, the device allows pendular freedom of up to 10° to the vertical, particularly preferably pendular freedom m the range 5 to 7°.

The elongate swivel means preferably comprises at its upper end an at least partially spherical portion rotatably mounted in a complimentarily shaped portion of the elongate housing (eg a substantially hollow spherical frame within the housing) . Particularly preferably the ball is provided with seats in the elongate housing which allow circulation whilst preventing leakage of fluid from the device. Preferably, the elongate swivel means is adapted to prevent axial movement of the rotatably mounted upper end of the elongate swivel means. For this purpose, a stopper is conveniently provided at the lower end of the housing.

Preferably the elongate swivel means comprises a wash pipe extending between the rotatably mounted upper end and the lower end adapted to attach a casing circulator.

In a preferred embodiment, the elongate housing is threadedly attached to a rigid portion on the derrick, for example the top drive of the derrick.

The swivel means is conveniently provided with a sub at its lower end. The casing circulator may be threadedly attached to the sub.

A preferred embodiment of the invention will now be described m a non-limitative sense with reference to the accompanying drawings in which:

Figure 1 is a longitudinal sectional view of a swivel device according to the invention, for use with a casing circulator to be used in the exploitation of hydrocarbon reserves, and showing the device in a skewed position;

Figure 2 is a similar view of the device m a vertical, in-line position; and,

Figure 3 is a detail view to an enlarged scale of part of the device.

With reference to the drawings, there is shc.rn a swivel device of the invention which can be pendularly displaced from an "m-line" position of Figure 2 and by an ar.gle of 5^", as shown in Figure 1. The device comprises a housing 1 threadedly attached to the rigid top drive on a derrick (not shown) . The device is capable of pendular motion ^" 3 and precessional motion 12 at its lower end. The housing 1 is provided with an upper retainer nut 3 threaded into the housing that secures a ball 4 m a complimentarily shaped portion at the lower end of the housing 1. The ball 4 has seats 5 and 6 situated above and below to allow for circulation without leakage. Ball 4 is secured to prevent axial movement by means of a solid steel lower stopper 7 integrally provided on the housing 1.

At the lower end of the device, a wash pipe 8 connects a sub 2 to the ball 4 m the housing 1 and seals it to the ball by means of seals 11. Upward axial movement of the wash pipe 8 is prevented by stopper 10 and upper retainer nut 3 threaded into the device.

The swivel arrangement shown in the drawings is capable of providing pendular freedom in the range of up to 10° to the vertical axis, and advantageously in the range 5 to 7 °.

It should be understood that a swivel device according to the invention can be assembled with a casing circulator by stabbing the device of the casing circulator at any convenient point in the casing.

Claims

1. A swivel device for use with a casing circulator m the exploitation of hydrocarbon reserves and comprising: an elongate housing (1) attachable at its upper end to a rigid portion on a derrick; and, elongate swivel means (8) having an upper end (4) rotatably mounted m said elongate housing (1) so as to provide precessional and pendular freedom to the lower end of said elongate swivel means, wherein said elongate swivel means is attachable at its lower end (2) to a casing circulator .

2. A swivel device as claimed m claim 1 , which is operable by hand to allow an attached casing circulator into or around the casing.

3. A swivel device as claimed in claim 1 or 2 and capable of providing full precessional freedom to the elongate swivel means (8) at its lower end.

4. A swivel device as claimed m any preceding claim and capable of providing pendular freedom of up to 10° to the vertical axis .

5. A swivel device as claimed in any preceding claim capable of providing pendular freedom m the range 5 to 7°.

6. A swivel device as claimed in any preceding claim wherein the elongate swivel means (8) comprises at its upper end an at least partially spherical portion (4) rotatably mounted m a complimentarily shaped portion (5, 6) of the elongate housing (J ) .

7. A swivel device as claimed in claim 6, wherein the complimentarily shaped portion (5, 6) of the elongate housing is a substantially hollow spherical frame within the elongate housing.

8. A swivel device as claimed m claim 6 or 7 wherein the at least partially spherical portion is an integral ball (4) .

9. A swivel device as claimed in any of claims 6, 7 or 8 wherein the complimentarily shaped portion of the elongate housing is provided with seats (5, 6) which allow circulation whilst preventing leakage of fluid from the device .

10. A swivel device as claimed m any preceding claim comprising means (10, 7) for preventing axial movement of the rotatably mounted upper end (4) of the elongate swivel means (8) .

11. A swivel device as claimed m claim 10 wherein the means for preventing axial movement is a stopper (7) provided at the lower end of the housing (1) .

12. A swivel device as claimed in any preceding claim wherein the elongate swivel means comprises a wash pipe (8) extending between the rotatably mounted upper end (4) and the lower end (2) .

13. A swivel device as claimed in any preceding claim wherein the swivel means is provided with a sub (2) at its lower end.

14. A swivel device as claimed in claim 13 wherein the casing circulator is threadedly attached to the sub.

15. A swivel arrangement comprising a swivel device as defined in any of claims 1 to 14 and a derrick, wherein the elongate housing is threadedly attached to a rigid portion on the derrick.

16. A swivel arrangement as claimed in claim 15 wherein the elongate housing is threadedly attached to the top drive of the derrick.