Holding and crushing device for barrier plug

Abstract

Disclosed is a plug arrangement including glass arranged in one or more seats in a plug housing, the seat or seats forming support members supporting the glass or glasses in an axial direction. At least one of the support members includes an axially displaceable split sleeve which, in one direction, includes a support ring/face abutting against the glass, and in the other direction a number of split sleeve arms arranged to rest against an edge arranged in the plug housing.

Claims

1. A plug arrangement in a plug housing comprising a barrier plug arranged in a support member, the support member comprising: a longitudinally displaceable split sleeve for supporting the barrier plug in the longitudinal direction on a first side of the barrier plug, wherein the longitudinally displaceable split sleeve comprises: an annularly shaped support face that supports the barrier plug in one direction, and the longitudinally displaceable split sleeve further comprises in the other direction a number of split sleeve arms arranged to rest against an edge in the plug housing.

2. The plug arrangement according to claim 1, wherein the support member further comprises a seat, the seat arranged to support the barrier plug on a second side of the barrier plug, wherein the second side is opposite of the first side.

3. The plug arrangement according to claim 1, wherein the support face abuts against the barrier plug.

4. The plug arrangement according to claim 1, wherein the barrier plug comprises one or more layers of glass material or ceramic material.

5. The plug arrangement according to claim 1, wherein the split sleeve arms are arranged to bend inwards towards the center of the well.

6. The plug arrangement according to claim 1, wherein a longitudinally displaceable locking ring is arranged to lock the arms of the split sleeve against the edge.

7. The plug arrangement according to claim 6, wherein the longitudinally displaceable locking ring is arranged to free the arms of the split sleeve from the edge.

8. The plug arrangement according to claim 7, wherein a release mechanism is arranged to displace the longitudinally displaceable locking ring in the longitudinal direction.

9. The plug arrangement according to claim 6, wherein a release mechanism is arranged to displace the longitudinally displaceable locking ring in the longitudinal direction.

10. A method of crushing a barrier plug, wherein the plug is arranged in a plug arrangement and the plug arrangement arranged in a plug housing, the plug arrangement comprising the barrier plug arranged in a support member, the support member comprising: a longitudinally displaceable split sleeve for supporting the barrier plug in the longitudinal direction on a first side of the barrier plug, wherein the longitudinally displaceable split sleeve comprises: an annularly shaped support face that supports the barrier plug in one direction, and the longitudinally displaceable split sleeve further comprises in the other direction a number of split sleeve arms arranged to rest against an edge in the plug housing; and a longitudinally displaceable locking ring arranged to lock the arms of the split sleeve against the edge, comprising the steps of: (a) displacing the longitudinally displaceable locking ring in a longitudinal direction; (b) causing the arms of the split sleeve to disengage from the edge; (c) releasing the barrier plug to be displaced in the longitudinal direction, and (d) displacing the barrier plug into contact with a crushing mechanism.

11. The method according to claim 10, wherein the support member further comprises a seat, the seat arranged to support the barrier plug on a second side of the barrier plug, wherein the second side is opposite of the first side.

12. The method according to claim 11, wherein the first side is on the reservoir side of the barrier plug and the second side is on the uphole side of the barrier plug.

13. The method according to claim 12, wherein the support face abuts against the barrier plug.

14. The method according to claim 10, wherein a release mechanism is arranged to displace the longitudinally displaceable locking ring in the longitudinal direction.

15. The method according to claim 14, wherein the longitudinally displaceable locking ring is arranged to be displaced away from the barrier plug.

16. The method according to claim 14, wherein the release mechanism is arranged to displace the longitudinally displaceable locking ring in the longitudinal direction by means of a hydraulic force.

17. The method according to claim 14, wherein the release mechanism is arranged to displace the longitudinally displaceable locking ring in the longitudinal direction by means of a mechanical force.

18. The method according to claim 14, wherein the longitudinally displaceable locking ring is supported by a hydraulic fluid, and the release mechanism being arranged to discharge the hydraulic fluid.

19. A plug system comprising: a pipe section; a plug arrangement in a plug housing comprising a barrier plug arranged in a support member, the support member comprising: a longitudinally displaceable split sleeve for supporting the barrier plug in the longitudinal direction on a first side of the barrier plug, wherein the longitudinally displaceable split sleeve comprises: an annularly shaped support face that supports the barrier plug in one direction, and the longitudinally displaceable split sleeve further comprises in the other direction a number of split sleeve arms arranged to rest against an edge in the plug housing; wherein the plug housing is arranged within the pipe section.

20. The system according to claim 19, wherein the support member further comprises a seat, the seat arranged to support the barrier plug on a second side of the barrier plug, wherein the second side is opposite of the first side.

Description

(1) In the following, there is provided a detailed, yet non-limiting description of the invention with reference to the following figures, wherein:

(2) FIG. 1 shows a sectional side view of an embodiment of a split sleeve according to the present invention,

(3) FIG. 2 shows a perspective view of the embodiment shown in FIG. 1,

(4) FIG. 3 shows an embodiment of the invention where the glass is installed and the arms of the split sleeve abut against the edge(s),

(5) FIG. 4 shows the same embodiment as FIG. 3, where the locking ring that holds the arms of the split sleeve against the edge(s) is freed as the glass is being crushed,

(6) FIG. 5 shows the same embodiment as in FIGS. 3 and 4, the glass having been crushed, and

(7) FIGS. 6-8 show details of FIGS. 3-5.

(8) FIG. 3 shows an embodiment of the present invention comprising a glass 1, a split sleeve 2 and a locking ring 3. On the well side 4 of the plug 5, the glass 1 rests against one or more seats 6 which may be formed directly in the housing or the pipe section 7. This seat (or these seats) 6 form support members for the glass 1 on the well side 4 of the glass. According to this embodiment, it is a substantial advantage that none of the support members located on the well side comprise O-rings or other elements which may move, collapse or get stuck in case a situation arises where full pressure is exerted from the reservoir side 8. By this, the risk of development of potential leakage pathways is substantially reduced. This in turn contributes to giving the plug 5 as much strength from the reservoir side 8 as possible, which is the most essential function of a barrier plug.

(9) Alternatively, the seat(s) may comprise one or more rings or sleeves abutting against one or more seats (not shown) which are formed directly in the housing 7, but in this case, the risk of development of potential leakage pathways around the glass 1 when full pressure hits from the reservoir side 8 is not avoided to the same extent.

(10) On the other side of the glass 1, on the reservoir side 8, the split sleeve 2 is located. According to the embodiment shown, the split sleeve 2 forms one or more seats against the glass 1 in the form of a ring surface 9. This ring surface 9 may be straight or inclined. This is most clearly shown in FIGS. 1 and 2. The thickness of the ring surface in a radial direction may be adapted so as to achieve an abutment surface which provides the strength required/desired in a downward direction, plus a considerable margin. In the outer periphery 10 of the ring surface 9, a number of notches or slots 11 (one or more) may be present which may extend in an axial direction. In one or more of the notches or slots 11, a knife or stud 12 may be arranged which is arranged in the wall 7 of the housing, either directly or via other elements, possibly with sealing members in the form of O-rings or sealing members having some other type of design. This is to avoid the development of possible leakage pathways. The studs or knives 12 may also be milled or in any other way formed directly into the housing or possibly into an element arranged fully or partly around the glass and/or the sleeve element.

(11) The studs or knives 12 will contribute to the crushing of the glass 1 in a crushing phase.

(12) On the other end of the split sleeve 2, on the end facing downwards towards the reservoir 8, FIGS. 1 and 2 show a possible embodiment of the arms 13 of the split sleeve. In this context, the number and design of the arms 13 is not essential. The arms 13 of the split sleeve are formed so as to be able to be bent inwards (towards the center of the well) or outwards (towards the wall of the pipe). The arms 13 of the split sleeve are mounted so as to have the end of the arms (in a downward direction) abutting against an edge 14 located on the pipe/housing wall 7. To prevent the arms of the split sleeve from bending inwards towards the center of the well and thus being able to move freely downwards, a locking ring 3 is arranged at the inside of the arms of the split sleeve and may be arranged in such a way that during the crushing phase, it is displaced axially downwards and thus away from the arms 13 of the split sleeve. The arms 13 of the split sleeve will then be able to bend inwards (towards the center of the wall) and thus let go of the edge 14 and freely move downwards. The glass 1 will follow the split sleeve 2 and hit the knives/studs 12 with great force. If the glass 1 has not been broken yet, it will most definitely break upon hitting the knives/studs 12.

(13) FIGS. 4 and 5 as well as 7 and 8 show how the locking ring 3 is displaced downwards so that the split sleeve 2 lets go of the edge 14, the glass 1 following the split sleeve and thus hitting the knives/studs 12. In FIGS. 5 and 8, the glass 1 has been crushed and washed away.

(14) Other alternative embodiments for displacing the locking ring 3 downwards are conceivable.

(15) It is conceivable that the locking ring 3 can free the split sleeve 2 by letting the locking ring go or displacing it in an upward direction (not shown). In this case, the arms 13 of the split sleeve and the locking ring 3 must be formed so as to be able to bend inwards even if the locking ring is displaced upwards towards the glass 1. At least, the locking ring must be let go upwards towards the glass to such an extent that the arms of the split sleeve are allowed to bend inwards more or less fully. In such an embodiment, the locking ring may be supported by a hydraulic fluid (not shown) which is discharged into one or more chambers when the plug is to be removed. Such a hydraulic support may also be used when the locking ring is arranged to be displaced downwards.

(16) A further embodiment of the locking ring 3 may comprise a screwable solution, i.e. a locking ring that comprises external threads and moves away from the arms by being screwed downwards out of the engagement of the arms. By choosing the appropriate pitch number of the threads on the outside of the locking ring, the locking ring may become self-locking. In such an embodiment, the release mechanism will be arranged such that an internally threaded sleeve ring arranged at the outside of the threads of the locking ring, is made to rotate upon release, which may be achieved in a variety of ways.

(17) When the locking ring 3 is located at the inside of the arms 13 of the split sleeve, the glass 1 is firmly arranged within the plug without the possibility of any substantial movement in an axial direction. The edge 14 will take up the force exerted by the glass via the split sleeve. The edge 14 may either be straight or inclined (possibly shaped otherwise). If it is inclined, it may contribute to pushing/bending the arms 13 inwards. The locking ring 3 will thus prevent the arms from being pushed/bent inwards when the split sleeve is locked as intended, while the arms 13 let go of the edge (more) easily when the locking ring 3 is freed/displaced.

(18) The locking ring 3 may be freed/released in various ways.

(19) One option is a mechanic or hydraulic connection with a ticker arrangement which is arranged in the wall of the pipe/housing on the upper side of the glass. When the ticker arrangement is released, the locking ring experiences a downward force which pushes it downwards away from the arms of the split sleeve, such that they bend inwards and thus free themselves from the edge. The split sleeve is thus free to move axially downwards.

(20) Another option may be to arrange a so-called burst disk (not shown) in one more channels extending from the upper side of the plug down to the locking ring. When the burst disk is exposed so sufficiently high pressure, it will rupture and allow well fluid to pass through the channels, pushing the locking rings downwards. This hydraulic pressure may optionally be applied to the upper side of the locking ring via axially extending pins or other mechanic means which act as a lock in an upward direction, but may move substantially freely in a downward direction.

(21) Such a mechanic transmission may also be combined which other release mechanisms 15, e.g. a ticker solution. The advantage of such a mechanic transmission is that it may act as a secure barrier towards the reservoir side in case the relative pressure from the lower side of the plug grows sufficiently large to rupture or damage a burst disk, ticker solution or other release mechanism that may be present from the lower side. A possible embodiment of such a mechanic transmission may be a pin (not shown) on the upper side abutting against a valve seat, i.e. the pin lies in a channel with a larger cross-section than the channel above the pin, the pin then being pushed against the valve seat and sealing the channel/connection when pressure is applied from the lower side. Such an embodiment will result in a plug which is «fail safe closed» both from the lower and from the upper side of the plug.

(22) The split sleeve 2 according to another embodiment may be formed of several parts which are assembled so as to function in the way described in the above (not shown). The arms 13 may comprise e.g. fully or partly loose parts (arms) which support one or more support rings which support the glass. According to another embodiment, the arms may be collapsible either by being pushed inwards by means of appropriate means, or by the arms being made of a material or comprising weaknesses which collapse/break within a defined load interval.