Drilling RIG mousehole device

Abstract

A mousehole device (1) configured for suspension below a rig floor structure (2), the mousehole device (1) comprising: a first elongate receiver part (10), the first elongate receiver part (10) configured to be fixed in the rig floor structure (2); a second elongate receiver part (11), the second elongate receiver part (11) 5 connected to the first elongate receiver part (10) and axially movable relative to the first elongate receiver part (10); and a damper (12) arranged between the first and second elongate receiver parts (10,11), the damper (12) having a damper material (13) arranged for plastic deformation by compression if the second elongate receiver part (11) is forced axially away from the first elongate receiver part (10).

Description

[0001] DRILLING RIG MOUSEHOLE DEVICE

[0002] The present disclosure relates to equipment for handling pipes on a drilling rig, and particularly to a mousehole device for temporarily holding pipes at the drilling rig.

[0003] BACKGROUND

[0004] During drilling operations, a mousehole device, i.e. an elongate pipe arrangement, is commonly used for temporarily storing drill pipe when preparing a drill string or when pulling a drill string out of a drilled wellbore. Mousehole devices are used in such regular pipe handling operations, and also form a safety-relevant component because a dropped section of pipe string may cause considerable damage to other rig components or to subsea equipment. Publications which may be useful to understand the field of technology include US 8,052,370 B2; EP 2 792 839 A1 ; WO 2010 / 050821 A1 ; EP 2 744 968 B1 ; WO 2015 / 022175 A2; WO 2020 / 132624 A1 ;

[0005] WO 2012 / 050458 A1.

[0006] On offshore drilling rigs, there are stringent space restrictions, and it is desirable to make such mousehole devices as compact and flexible as possible. When installed, the mousehole device extend downwardly below a drill floor, and may therefore hinder other operations below the drill floor, such as operations on a cellar deck or in a moonpool area. For some offshore rigs, there may also be a risk of large waves reaching the mousehole device and causing undesirable contact with sea water. Since the mousehole device needs to correspond to the length of pipe (such as drill string pipe) that it is intended to handle, the length of the mousehole device may be considerable. It is, however, desirable to reduce the length of the mousehole device as much as possible, both during transport, handling and operation.

[0007] There is consequently a need to improved technology in this area, and the present disclosure has the objective to provide such improvements, or at least useful alternatives to the state of the art. SUMMARY

[0008] In an example, there is provided a mousehole device configured for suspension below a rig floor structure, the mousehole device comprising: a first elongate receiver part, the first elongate receiver part configured to be fixed in the rig floor structure; a second elongate receiver part, the second elongate receiver part connected to the first elongate receiver part and axially movable relative to the first elongate receiver part; and a damper arranged between the first and second elongate receiver parts, the damper having a damper material arranged for plastic deformation by compression if the second elongate receiver part is forced axially away from the first elongate receiver part.

[0009] The detailed description and appended claims below outline further inventive examples and embodiments.

[0010] BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The invention will now be explained in greater detail with reference to the accompanying drawings, in which:

[0012] Fig. 1 is a perspective view of a mousehole device of an example in an operational state.

[0013] Fig. 2 is a perspective view of the mousehole device of Fig. 1 in a position after a dropped object incident.

[0014] Fig. 3 illustrates parts of a mousehole device having a deformable damper.

[0015] Fig. 4 illustrates parts of the mousehole device having a bottom damper.

[0016] Fig. 5 illustrates parts of a mousehole device according to another example.

[0017] Fig. 6 illustrates a deformable damper having a damper material enclosed in a protective compartment.

[0018] Figs 7 and 8 illustrate a mousehole device having a telescopic lower elongate receiver part. DETAILED DESCRIPTION

[0019] The present disclosure relates to a mousehole device used in drilling operations, particularly for handling tubulars such as sections of drill string pipe at or below a rig floor structure. Traditional mousehole devices often comprise damping mechanisms to avoid potential damage if tubulars are dropped or mishandled. Such damping mechanisms may, however, increase the size (such as the length) of the mousehole device. Additionally, it is desirable that the damping effect is predictable and does not vary to a large extend if activated. (I.e., that the damping force provided is as constant as possible over the length of the damping motion.) This disclosure aims to address these issues by introducing a mousehole device with improved damping capabilities.

[0020] Figs 1 and 2 illustrate a mousehole device 1 according to an example. The mousehole device 1 is configured to be suspended below a rig floor structure 2, such as a drill floor having a rig, pipe handling equipment, a driller’s cabin, etc. thereon. A first elongate receiver part 10 of the mousehole device 1 is fixed at the rig floor structure 2, for example at beams on the rig floor structure 2. A second elongate receiver part 11 is connected to and (when in use) suspended from the first elongate receiver part 10. The first and second elongate receiver parts 10,11 together define an inner receptacle volume of the mousehole device 1 operable to receive a pipe, such as a section of drill string pipe.

[0021] In the illustrated example, the first and second elongate receiver parts 10,11 are tubular parts. Alternatively, the first and second elongate receiver parts 10,11 may, for example, be made up of bracings, rods or other structure constructed to form elongate receiver parts having an inner receptacle volume and being suitable for this purpose.

[0022] The second elongate receiver part 11 is designed to be movable axially relative to the first elongate receiver part 10 in the event of an undesired incident, such as a dropped object incident. This is illustrated by the downward arrow in Fig. 2, and Fig. 2 illustrates the second elongate receiver part 11 in a lowered position after such an incident. Referring now to Fig. 3, a damper 12 is positioned between the first and second elongate receiver parts 10,11. The damper 12 is arranged at the interface between the first and second elongate receiver parts 11,12, i.e. at a lower part of the first elongate receiver part 10 and at an upper part 11a of the second elongate receiver part 11. The damper 12 includes a damper material 13 capable of plastic deformation under compression, effectively absorbing and dissipating impact energy. The damper material 13 may, for example, be formed in a honeycomb structure made from corrugated aluminium to provide advantageous damping characteristics.

[0023] The damper material 13 is arranged between an upper flange 14 fixed at the second elongate receiver part 11 and a lower flange 15 fixed at the first elongate receiver part 10. Consequently, if an impact of a falling object, such as a section of drill string pipe, forces the second elongate receiver part 11 away from the first elongate receiver part 10, the damper material 13 will be compressed and thereby provide a damping effect while absorbing energy.

[0024] As noted, in the illustrated example the first and second elongate receiver parts 10,11 are tubulars. The tubulars are arranged in a pipe n-pipe configuration at their interface. The damper material 13 is in this example arranged in an annulus space between the first elongate receiver part 10 and the second elongate receiver part 11. Alternatively, the damper material 13 may be arranged in a suitable holder (or holders), such as one or more cassettes, arranged between the flanges 14,15.

[0025] Advantageously, illustrated schematically in Fig. 6, the damper material 13 may be enclosed in a protective compartment 18 such as to provide protection against water, dirt, etc. The protective compartment 18 may, for example, be made up of a housing, a metal sheet, a rubber or plastic sheet, or other suitable parts. When the first and second elongate receiver parts 10,11 are tubular parts, the damper material 13 is advantageously arranged in the annulus space between the tubulars and the protective compartment 18 is at least partly defined by the tubular parts. In this manner, the integrity of the damper material 13 can be ensured, and contamination can be prevented.

[0026] Illustrated in Fig. 4, the second elongate receiver part 11 may comprise a bottom damper 19 at a lower part 11b thereof. The bottom damper 19 may act to provide part of the damping and energy dissipation effect. The bottom damper 19 may, for example, comprise a material which has lower resistance to plastic deformation than the damper material 13. The bottom damper 19 may particularly provide damping effect during the initial stages of an impact which forces the second elongate receiver part 11 to move downwardly relative to the first elongate receiver part 10.

[0027] The first elongate receiver part 10 may advantageously makes up less than half of a full length of the mousehole device 1, such as less than one-third (33%) of the full length or less than one-fifth (20%) of the full length. In this manner, the damper 12 can be arranged at a vertically high position of the mousehole device 1.

[0028] Alternatively, as illustrated in Fig. 5, the damper 12 may be arranged at a lowermost part of the mousehole device 1. In this configuration, the first elongate receiver part 10 may be considerably longer than the second elongate receiver part 11. The damper 12 may, for example, be arranged at the lowermost 20% or the lowermost 10% of the mousehole device 1 (relative to the full length of the mousehole device 1). In other examples, the damper 12 may be arranged at other locations, for example where the first and second elongate receiver parts 10,11 have approximately the same length, and the damper 12 is positioned approximately at a middle section of the mousehole device 1.

[0029] Illustrated in Figs 7 and 8, the mousehole device 1 may be telescopic, wherein the second elongate receiver part 11 has first and second telescopic sections 11c,11d, allowing for retraction during handling, installation, removal or when other operations take place below the rig floor structure 2. The mousehole device 1 may, for example, be arranged on a skid beam at the rig floor structure 2 and configured for telescopic retraction and skidding sideways and out of the way when other operations are required in the moon pool area. Fig. 7 illustrates the mousehole device 1 in a retracted state having an extension L1 below a drill floor, while Fig. 8 illustrates the mousehole device 1 in an extended, operational state where the mousehole device 1 extends a length L2 below the drill floor.

[0030] In the example shown in Figs 7 and 8, the second elongate receiver part 11 is telescopic. Alternatively, for example in a configuration incorporating a damper at the lower part 11b of the second elongate receiver part 11 as illustrated in Fig. 5, the first elongate receiver part 10 may be telescopic. Advantageously, the mousehole device 1 provides efficient and predictable damping performance, while allowing the length of the mousehole device 1 to be minimised. For example, space and structure for damper material at the lower part of the mousehole device 1 can be reduced or eliminated. In this manner, a compact and safe mousehole device 1 can be provided to reduce the likelihood of damage to the rig floor structure and underlying components in case of unintended events, such as dropped objects.

[0031] The invention is not limited by the embodiments described above; reference should be had to the appended claims.

Claims

CLAIMS1 . A mousehole device (1) configured for suspension below a rig floor structure (2), the mousehole device (1) comprising: a first elongate receiver part (10), the first elongate receiver part (10) configured to be fixed in the rig floor structure (2); a second elongate receiver part (11), the second elongate receiver part (11) connected to the first elongate receiver part (10) and axially movable relative to the first elongate receiver part (10); and a damper (12) arranged between the first and second elongate receiver parts (10,11), the damper (12) having a damper material (13) arranged for plastic deformation by compression if the second elongate receiver part (11) is forced axially away from the first elongate receiver part (10).

2. The mousehole device (1) according to claim 1 , wherein the first elongate receiver part (10) makes up less than half of a full length of the mousehole device (1), such as less than one-third of the full length or less than one-fifth of the full length.

3. The mousehole device (1) according to any preceding claim, wherein the second elongate receiver part (11) comprises first and second telescopic elongate receiver sections (11 c, 11d).

4. The mousehole device (1) according to any preceding claim, wherein the damper (12) is arranged at a lower part of the first elongate receiver part (10) and at an upper part (11a) of the second elongate receiver part (11).

5. The mousehole device (1) according to any preceding claim, wherein the second elongate receiver part (11) comprises a bottom damper (19) at a lower part (11 b) thereof.

6. The mousehole device (1) according to any preceding claim, wherein the damper material (13) is arranged between an upper flange (14) fixed at thesecond elongate receiver part (11) and a lower flange (15) fixed at the first elongate receiver part (10).

7. The mousehole device (1) according to any preceding claim, wherein the first and second elongate receiver parts (10,11) are tubular parts.

8. The mousehole device (1) according to claim 7, wherein the damper material (13) is arranged in an annulus space between the first elongate receiver part (10) and the second elongate receiver part (11).

9. The mousehole device (1) according to any preceding claim, wherein the damper material (13) is partly or fully enclosed in a protective compartment (18).

10. The mousehole device (1) according to claim 9, wherein the first and second elongate receiver parts (10,11) are tubular parts and wherein the protective compartment (18) is an annulus space at least partly defined by the tubular parts.

11. The mousehole device (1) according to any preceding claim, wherein the damper material (13) is formed in a honeycomb structure which is made of corrugated metal, such as corrugated aluminium, for example wherein the damper material (13) is formed exclusively from a honeycomb structure which is made of corrugated metal, such as corrugated aluminium.

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