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NO20160767A1 - A device for operation on a wellhead of a hydrocarbon well - Google Patents

A device for operation on a wellhead of a hydrocarbon well Download PDF

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Publication number
NO20160767A1
NO20160767A1 NO20160767A NO20160767A NO20160767A1 NO 20160767 A1 NO20160767 A1 NO 20160767A1 NO 20160767 A NO20160767 A NO 20160767A NO 20160767 A NO20160767 A NO 20160767A NO 20160767 A1 NO20160767 A1 NO 20160767A1
Authority
NO
Norway
Prior art keywords
wellhead
attachment unit
attachment
unit
arrangement
Prior art date
Application number
NO20160767A
Inventor
Kenneth Thunheim
Bjørn Heradstveit
Olav Horpestad
Original Assignee
Umac As
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Umac As filed Critical Umac As
Priority to NO20160767A priority Critical patent/NO20160767A1/en
Priority to PCT/NO2017/050105 priority patent/WO2017192043A1/en
Priority to PCT/NO2017/050107 priority patent/WO2017192045A1/en
Publication of NO20160767A1 publication Critical patent/NO20160767A1/en

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B31/00—Fishing for or freeing objects in boreholes or wells
    • E21B31/12—Grappling tools, e.g. tongs or grabs
    • E21B31/16—Grappling tools, e.g. tongs or grabs combined with cutting or destroying means
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B29/00—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
    • E21B29/08—Cutting or deforming pipes to control fluid flow
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B23/00—Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B29/00—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
    • E21B29/12—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground specially adapted for underwater installations
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B31/00—Fishing for or freeing objects in boreholes or wells
    • E21B31/12—Grappling tools, e.g. tongs or grabs
    • E21B31/20—Grappling tools, e.g. tongs or grabs gripping internally, e.g. fishing spears

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Marine Sciences & Fisheries (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
  • Power Steering Mechanism (AREA)

Description

A DEVICE FOR OPERATION ON A WELLHEAD OF A HYDROCARBON WELL
Introduction
The present invention relates to a device for operation on a wellhead of a hydrocarbon well. The device comprises a support structure, and an attachment arrangement at the support structure adapted to attach the device to the wellhead, wherein at least a portion of the device is adapted to be inserted in an opening of the wellhead provided with or to be provided with a separating cut.
The present invention also relates to an arrangement and a method for operation on a wellhead of a hydrocarbon well.
Prior art
Wellheads are arranged at the surface of an oil or gas well, such at the seabed of the sea for a subsea wellhead. The function of the wellhead is to provide a structural and pressure-containing interface for the drilling and production equipment. After the operation at the well has been terminated, it is required that the well is plugged and the wellhead is removed. In regards of a subsea wellhead, it is a requirement from the authorities that the wellhead is removed at a certain depth below the seabed.
Prior art devices for removing subsea wellheads rely on methods involving cutting using high pressure water and sand, blasting, or drilling down into the wellhead. Method involving cutting using high pressure water and sand suffer from the disadvantage of requiring extensive equipment on a rig or a vessel, and also require extensive offshore personnel for the operation. Methods involving blasting require on the other hand less equipment but have the disadvantage of negatively effecting the marine environment. Methods of drilling into the wellhead have the disadvantage of being slow. Furthermore, a general disadvantage with prior art devices for removing subsea wellheads is that the separating cut can not be verified.
EP2281998A2 disclosed an apparatus for a subsea intervention on a wellhead. The apparatus comprises a grip member adapted engage with the wellhead and a rotary cutting assembly for generating a separating cut.
Summary of the invention
The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least provide a useful alternative to prior art. A first object of the invention is to provide a device for operation on a wellhead of a hydrocarbon well that enables verification of a separating cut without connecting lifting means for lifting the wellhead from its position of installation. A second object of the invention is to provide a device for operation on a wellhead of a hydrocarbon well that requires less equipment arranged on a rig or a vessel. A third object of the invention is to provide a device for operation on a wellhead of a hydrocarbon well that can be operated with less personnel than prior art devices.
These objects are achieved by means of a device for operation on a wellhead of a hydrocarbon well, the device comprises a support structure, and an attachment arrangement at the support structure adapted to attach the device to the wellhead, wherein at least a portion of the device is adapted to be inserted in an opening of the wellhead provided with or to be provided with a separating cut. The device ischaracterised in thatthe attachment arrangement comprises a first attachment unit adapted to form a first attachment to an upper portion of the wellhead at an upper side of said cut, and second attachment unit adapted to form a second attachment to a lower portion of the wellhead at a lower side of the cut that is opposite to the upper side, wherein the device further comprises a displacement unit connected to the first attachment unit and the second attachment unit, which displacement unit is adapted to generate a force acting to further separating the first attachment unit and the second attachment unit from each other after that the first attachment and second attachment have been established.
The device enables the separating cut to be verified by means of the first and second attachment using the first and second attachment unit on opposite parts in regards to the separating cut, and thereafter, by means of the displacement unit, generating a force that acts to further separate the first and second attachment unit from each other. If the first and second attachment unit are displace away from each other to certain extent, it can be concluded that a sufficient separating cut is present to enable the wellhead to be lifted away from its installed position. On the other hand, if the first and second attachment units are prevented from being further separated from each other when subjected to the separating force, it can be concluded that the separating cut has not fully been established to enable the removal of the wellhead from its position of installation.
The device has the advantage that the separating cut can be verified without that lifting means being attached to the wellhead and a lifting operation from a rig or a vessel initiated. Accordingly, after the cut has been verified, it is assured that no further cutting operation will be necessary and the time for the removal of the wellhead can be reduced.
According to an embodiment of the invention, said force is arranged with a magnitude corresponding to the existence of a sufficient separating cut for removal of the wellhead. Preferably, the force is arranged with a magnitude corresponding to at least the weight of the upper portion of the wellhead.
According to an embodiment of the invention, the device comprises means for measuring the displacement of the first attachment unit and second attachment unit in respect to each other. If the displacement of the first attachment unit and the second attachment unit is equal to or above certain value, it can be concluded that a sufficient separating cut is present for lifting the wellhead from its installed position. On the other hand, if the displacement of the first attachment unit and the second attachment unit is less than the certain value, it can be concluded that there is not a sufficient separating cut present for lifting the wellhead from its position and accordingly the cutting operation needs to be continued.
According to an embodiment of the invention, the first attachment unit and the second attachment unit comprise a respective disengaged state in which the device is movable within the opening of the wellhead and a respective engaged state in which the first attachment unit and the second attachment unit engage with the respective upper portion and the lower portion of the wellhead.
In the disengaged state, the first and the second attachment unit lack essentially engagement with the opening of the wellhead. Accordingly, the device is movable within the opening of the wellhead when the first and the second attachment unit are in the disengaged state. Contrary, in the engaged state, the first and the second attachment unit are in engagement with the opening of the wellhead. Accordingly, the device is rest riet ed from movement within the opening of the wellhead when the first and the second attachment unit are in the engaged state.
According to an embodiment of the invention, the second attachment unit comprises an expandable engagement member adapted to engage with an inner envelope surface of the opening at the lower portion of the wellhead when the second attachment unit is in the engaged state. The second attachment if formed by means of expanding the second attachment unit to contact with the inner envelope surface at the lower portion of the wellhead.
According to an embodiment of the invention, the first attachment unit comprises an expandable engagement member adapted to engage with an inner envelope surface of the opening at the upper portion of the wellhead when the first attachment unit is in the engaged state. The first attachment if formed by means of expanding the first attachment unit to contact with the inner envelope surface at the upper portion of the wellhead.
According to an embodiment of the invention, the displacement unit comprises a motor unit acting on the first attachment unit and the second attachment unit so that the first attachment unit and the second attachment unit are adapted to be displaced in respect to each other between a first spacing and a second spacing, wherein the second spacing is largerthan the first spacing. The motor unit is for example an electric motor, a hydraulic cylinder, et cetera. According to an embodiment of the invention, the first attachment unit and second attachment unit comprise a respective further motor unit, a wedge shaped engagement member and a contact member in contact with the engagement member, wherein the further motor unit is adapted to displace the engagement member between a first position corresponding to the disengaged state of the attachments units and a second position corresponding to the engaged state of the attachment units.
The displacement of the wedge shaped engagement member enables controllable change of the attachment units between the engaged state and the disengaged state. The extension of the attachment units is smaller in the disengaged state than in the engaged state. The further motor unit is for example an electric motor, a hydraulic cylinder, etcetera.
According to an embodiment of the invention, the support structure is elongated and the first attachment unit and the second attachment unit are spaced apart along a longitudinal axis of the support structure.
According to an embodiment of the invention, the difference between that second distance and first distance is in the range of 0,1 - 50 mm, preferably 0,5 - 20 mm.
According to an embodiment of the invention, the device comprises a cutting device arranged at the support structure, which cutting device is adapted to provide said cut in the wellhead.
According to an embodiment of the invention, the cutting device is arranged at an end part of the support structure. The end part of the support structure relates to the part that is first inserted into the opening of the wellhead. By executing the separating cut at the end of the device, it is assured that cutting material from the cut is not interfering with the first and the second attachment units.
According to an embodiment of the invention, the cutting device is arranged between the first attachment unit and the second attachment unit. By arranging the cutting device between the first attachment unit and the second attachment unit, cutting and verification of the separating cut can be done without displacement of the device within the opening of the wellhead.
According to an embodiment of the invention, the cutting device comprises a rotary arranged cutting member comprising a compressed state in which the device is movable within the opening of the wellhead and an extended state in which cutting device is brought into contact with the wellhead for providing the separating cut.
The objects of the invention is further achieved by means of an arrangement for operation on a wellhead of a hydrocarbon well. The arrangement comprises the device according to any of claim 1-11 and a further displacement unit for displacing the device within the opening of the wellhead. The further displacement unit is used for arranging the device in certain position in the opening of the wellhead so that the first attachment unit is positioned at the upper portion of the wellhead and the second attachment unit is positioned at the lower portion of the wellhead.
According to an embodiment of the invention, the further displacement unit comprises a winch comprising a wire connected to the device.
According to an embodiment of the invention, the further displacement unit comprises means for determining the displacement of the device within the opening of the wellhead. The means for determining is for example an encoder. By means of the means for determining the displacement of the device within the opening of the wellhead, the device can be arranged to its desired position within the opening of the wellhead.
According to an embodiment of the invention, the arrangement further comprises a guide arrangement for positioning the arrangement in a predetermined position in respect to the wellhead. The guide arrangement comprises preferably a guide funnel adapted to be guided to the predetermined position in respect to the wellhead by means of a guide post arranged at the wellhead.
According to an embodiment of the invention, the arrangement comprises a locking device for locking the position of the arrangement to the predetermined position. The locking device assures a firm attachment of the arrangement in respect of the wellhead so that the device can be positioned accurately in the opening of the wellhead.
According to an embodiment of the invention, the arrangement comprises means for control and power supply of the device and the further displacement unit. The control means is for example a control unit comprises a logic unit, such as a CPU. The power supply may be in form of connection of electric power, hydraulic pumps, etcetera.
According to an embodiment of the invention, the arrangement comprises a remotely operated vehicle and said means for control and power supply are provided in the remotely operated vehicle connected to the device and the further displacement unit.
The object of the invention is furthermore achieved by means of a method for operation on a wellhead of a hydrocarbon well by means of an arrangement according to claim 18, which wellhead is provided with or is to be provided with a separating cut, the method comprises the steps of
- setting the first attachment unit and the second attachment unit to the disengaged state,
- arranging the device in the opening of the wellhead so that the first attachment unit is positioned at an upper portion of the wellhead at an upper side of said cut and the second attachment unit is positioned at a lower portion of the wellhead at a lower side of the cut that is opposite to the upper side,
- setting the first attachment unit and the second attachment unit to the engaged state, and
- generating a force that acts to separate the first attachment unit and the second attachment unit from each other.
According to an embodiment of the invention, the method comprises
- measuring a displacement of the first attachment unit and the second attachment unit in respect to each other, and - determining that a sufficient separating cut exists if the displacement is equal or exceeding a pre-
determined distance.
According to an embodiment of the invention, the method comprises
- arranging the device in the opening of the wellhead so that the cutting device is in a position for the intended cut, and
- generating a cut in the wellhead by means of the cutting device.
According to an embodiment of the invention, the method comprises
- after generating the cut, if necessary, rearranging the device in the opening of the wellhead to a position where the first attachment unit is positioned at an upper portion of the wellhead at an upper side of said cut and the second attachment unit is positioned at a lower portion of the wellhead at a lower side of the cut.
According to an embodiment of the invention, the method comprises
- determining that an insufficient separating cut exists if the measured displacement of the first attachment unit and the second attachment unit in respect to each other is less than a predetermined distance.
According to an embodiment of the invention, the method comprises
- if an insufficient separating cut has been determined, if necessary, rearranging the device in the opening of the wellhead so that the cutting device is in a position of the cut, and
- continue cutting the wellhead at the position of the cut.
Brief description of the drawings
In the following is described examples of preferred embodiments illustrated in the accompanying drawings, wherein: Fig. 1 discloses an arrangement for operation on a wellhead of a hydrocarbon well according to a first embodiment of the invention; Fig. 2 discloses an arrangement for operation on a wellhead of a hydrocarbon well according to a second embodiment of the invention; Fig. 3 discloses a flow chart of a method for operation on a wellhead of a hydrocarbon well
according to a third embodiment of the invention;
Fig. 4 discloses a flow chart of a method for operation on a wellhead of a hydrocarbon well
according to a fourth embodiment of the invention;
Detail description
In fig. 1, an arrangement 1 for operation on a wellhead 3 of a hydrocarbon well according to a first embodiment of the invention is disclosed. In particular the arrangement 1 is adapted for forming and verifying a separating cut 5 in the wellhead 3.
The arrangement 1 comprises a device 10 for operating on the wellhead 3. In fig. 1, the device 10 is inserted into an opening 12 in the wellhead 3. In the following the device 10 will be explained in details.
The device 10 comprises an elongated support structure 14 and an attachment arrangement for controllably attaching the device 10 to the wellhead 3. The attachment arrangement comprises a first attachment unit 20 and a second attachment unit 22.
The device 10 is adapted to be positioned in the opening 12 of the wellhead 3 so that the first attachment unit 20 is arranged at an upper portion UP of the wellhead 3 and so that the second attachment unit 22 is arranged at a lower portion LP of the wellhead 3. The upper portion UP of the wellhead 3 is located at an upper side in respect to the separating cut 5 and the lower portion LP of the wellhead 3 is located at a lower side in respect to the separating cut 5.
The first attachment unit 20 is adapted to form a first attachment to the upper portion UP of the wellhead 3. Correspondingly, the second attachment unit 22 is adapted to form a second attachment to the lower portion LP of the wellhead 3. The first attachment unit 20 and the second attachment unit 22 comprise a respective disengaged state in which the device 10 is movable within the opening 12 of the wellhead 3 and a respective engaged state in which the first attachment unit 20 and the second attachment unit 22 engage with the respective upper portion UP and the lower portion LP of the wellhead 3, and thereby forming a firm attachment with the respective parts of the wellhead 3.
In the disclosed embodiment, both the first attachment unit 20 and the second attachment units 22 are adapted to form the respective first and second attachment with an inner envelope surface of the opening 12 of the wellhead 3.
The device 10 further comprises a displacement unit 30 connected to the first attachment unit 20 and the second attachment unit 22 by means of a connection element 31. The displacement unit 30 is adapted to generate a force a eting to further separate the first attachment unit 20 and the second attachment unit 22 from each other after that the first attachment and second attachment have been established with the wellhead 3. In the disclosed embodiment, the displacement unit 30 comprises a motor unit 32 a eting on the first attachment unit 20 and the second attachment unit 22. The motor unit 32 is for example an electric motor, a hydraulic cylinder, etcetera.
According to an embodiment of the invention, the first attachment unit 20 and second attachment unit 22 comprise a respective further motor unit 33, a wedge shaped engagement member and a contact member in contact with the engagement member. The further motor unit 33 is adapted to displace the engagement member between a first position corresponding to the disengaged state of the attachments units 20, 22 and a second position corresponding to the engaged state of the attachment units 20, 22. The further motor unit 33 is for example an electric motor, a hydraulic cylinder, etcetera.
Preferably, the force has a magnitude that exceeds the weight of the upper portion UP of the wellhead 3. The separation cut 5 in the wellhead 3 is verified by means of the combined operation of the first attachment unit 20, the second attachment 22 and the displacement unit 30.
The device 10 further comprises means 34 for measuring the displacement of the first attachment unit 20 and second attachment unit 22 in respect to each other. Thereby, the displacement of the attachment units 20, 22 induced by the displacement unit 30 is measured. The means 34 for measuring the displacement of the first attachment unit 20 and second attachment unit 22 is for example an encoder.
If the measured displacement of the first attachment unit 20 and second attachment unit 22 is equal to or larger than a certain distance, it can be concluded that a sufficient separating cut 5 is
present. Contrary, if the measured displacement of the first attachment unit 20 and second attachment unit 22 is less than the certain distance, it can be concluded that an insufficient separating cut 5 is present and the cutting operation on the wellhead 3 needs to be continued before the wellhead
3 can be lifted away from its installed location.
The device 10 further comprises a cutting device 40 arranged at the support structure 14. The cutting device 40 is adapted to provide a cut in the wellhead 3. The cutting device 40 is for example rotary cutting blade comprising a compressed state and an extended state. In the compressed state, the cutting device 40 lacks essential contact with the envelope surface of the opening 12 of the wellhead 3 and the device 10 is freely movable within the opening 12 of the wellhead 3. In the extended state, the cutting device 40 is in contact with the wellhead 3 for providing the separating cut 5 in the wellhead 3.
According to the first embodiment of the invention in fig. 1, the cutting device 40 is arranged at an end part of the support structure 14. Accordingly, the first attachment unit 20, the second attachment unit 22 and the displacement unit 30 are arranged above the cutting device 40 on the support structure 14. By arranging the cutting device 40 at the end part of the support structure 14, it is assured that no cutting material produced when generating the cut 5 is interfering with the operation of the first attachment unit 20, the second attachment unit 22 and the displacement unit 30.
The arrangement 1 further comprises a further displacement unit 50, such as a winch 52 and cable 54 connected to the device 10. The further displacement unit 50 is adapted to displace the device 10 in the opening of the wellhead 3 to a desired position for the separating cut 5 and if necessary to a new position for verifying the formed separating cut 5.
The further displacement unit 50 comprises means 56 for determining the displacement of the de vice 10 within the opening of the wellhead 3. Preferably, the means 56 for determining the displacement of the device 10 is an encoder.
The arrangement 1 further comprises a guide arrangement 60 for positioning the arrangement 10 in a predetermined position in respect to the wellhead 3. In the disclosed embodiment, the guide arrangement 60 is adapted to be guided by a guide element 62, such as a plurality of guide posts, arranged at the wellhead 3. The arrangement 1 further comprises a locking device 64 for locking the position of the arrangement 1 to the predetermined position. Thereby, it is assured that the arrangement is maintained in a set position in respect to the wellhead 3 during operation of the arrangement 1.
The arrangement 1 further comprises means 70 for control and power supply of the device 10 and the further displacement unit 50. In the disclosed embodiment, the arrangement comprises a Remotely operated vehicle (ROV) 72 comprising the means 70 for control and power supply. The ROV 72 is further provided with a control unit 74 for controlling the operation of the arrangement 1. The control unit 74 further comprises a logic unit adapted to receive information from the first encoder 34 and determine if a sufficient separating cut 5 is present on basis of the information from the first encoder 34.
The arrangement further comprises connection device 76 adapted to enable the ROV 72 to be connected and disconnected from the device 10. Thereby, a single ROV 72 can be used to power and control a plurality of devices 10 at different wellheads 3. Fig. 2 discloses a second embodiment of the invention. The second embodiment of the invention differs from the first embodiment in that the cutting device 40 is arranged between the first attachment unit 20 and the second attachment unit 22. This position of the cutting device 40 provides the advantage that no displacement of the device 10 is necessary between generating and verifying the separating cut 5. Accordingly, in the event that it has been determined that an insufficient separating cut 5 is present, the continued cutting operation can be initiated without displacement of the device 10 within the opening of the wellhead 3. Fig. 3 discloses a flow chart of a method for operation on a wellhead 3 of a hydrocarbon well according to a third embodiment of the invention.
In a step 110, the method comprises setting the first attachment unit 20 and the second attachment unit 22 to the disengaged state. Thereby, insertion of the device 10 in the opening 12 of the wellhead 3 is enabled. Furthermore, the device 10 is displaceable between different positions within the opening 12 of the wellhead 3.
In a step 120, the method comprises arranging the device 10 in the opening of the wellhead 3 so that the first attachment unit 20 is positioned at an upper portion UP of the wellhead 3 at an upper side of a separating cut 5 and the second attachment unit 22 is positioned at a lower portion LP of the wellhead 3 at a lower side of the separating cut 5 that is opposite to the upper side. Accordingly, the device 10 is positioned in the opening 12 of the wellhead 3 so to enable attachment of the attachment units 20, 22 at different parts of the wellhead 3 in respect to the separating cut 5.
In a step 130, the method comprises setting the first attachment unit 20 and the second attachment unit 22 to the engaged state. Thereby, the first attachment unit 20 forms the first attachment to the inner envelope surface of the upper portion UP of the wellhead 3 and the second attachment unit 22 forms the second attachment to the inner envelope surface of the lower portion LP of the wellhead 3.
In a step 140, the method comprises generating a force that acts to separate the first attachment unit 20 and the second attachment unit 20 from each other. The force is generated by the displacement unit 30 arranged connected between the first attachment unit 20 and the second attachment unit 22. On basis thereof, it can be concluded if a sufficient separating cut 5 is present or not.
Preferably, in a step 150, the method comprises measuring a displacement of the first attachment unit 20 and the second attachment unit 22 in respect to each other, and in a step 160, determining that a sufficient separating cut 5 exists if the displacement is equal to or exceeding a predetermined distance. Correspondingly, it is determined that an insufficient separating cut 5 exists if the measured displacement of the first attachment unit 20 and the second attachment unit 22 in respect to each other is less than the predetermined distance.
Fig. 4 discloses a flow chart of a method for operation on a wellhead 3 of a hydrocarbon well according to a fourth embodiment of the invention. The method in fig. 4 differs from the embodiment in fig. 3 in that the method further comprises the operation of generating the separating cut 5 in the wellhead 3.
In a step 112, the method comprises arranging the device 10 in the opening of the wellhead 3 so that the cutting device 40 is in a position for the intended cut. In a step 114, the method comprises generating a separating cut 5 in the wellhead 3 by means of the cutting device 40.
Subsequent to generating the separating cut 5, the step of verifying the cut is executed. Dependent on the configuration of the device 10, a displacement of the device 10 may be necessary between the position of generating the separating cut 5 and the position of verifying the separating cut 5.
The method comprises, in a step 170, if an insufficient separating cut 5 has been determined, continue cutting the wellhead 3 at the position of the separating cut 5. The step 170 may involve displacement of the device 10 to enable the cutting device 40 to be arranged in the position of the separating cut 5. If on the other hand, it is determined that a sufficient separating cut 5 is present, the method is stopped and the wellhead can be lifted away from its installed position.
It should be noted that the above-mentioned embodiments illustrate ratherthan limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The arti ele "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.
The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims (23)

1. A device (10) for operation on a wellhead (3) of a hydrocarbon well, the device (10) comprises: - a support structure (14), and - an attachment arrangement at the support structure (14) adapted to attach the device (10) to the wellhead (3), wherein at least a portion of the device (10) is adapted to be inserted in an opening (12) of the wellhead (3) provided with or to be provided with a separating cut (5),characterised in that the attachment arrangement comprises a first attachment unit (20) adapted to form a first attachment to an upper portion (UP) of the wellhead (3) at an upper side of said cut (5), and second attachment unit (22) adapted to form a second attachment to a lower portion (LP) of the wellhead (3) at a lower side of said cut (5) that is opposite to the upper side, wherein the device (10) further comprises a displacement unit (30) connected to the first attachment unit (20) and the second attachment unit (22), which displacement unit (30) is adapted to generate a force a eting to further separating the first attachment unit (20) and the second attachment unit (22) from each other after that the first attachment and second attachment have been established.
2. The device (10) according to claim 1, wherein said force is arranged with a magnitude corresponding to at least the weight of the upper portion (UP) of the wellhead (3).
3. The device (10) according to any of claim 1 and 2, wherein the device (10) comprises means for measuring the displacement of the first attachment unit (20) and second attachment unit (22) in respect to each other.
4. The device (10) according to any of the previous claims, wherein the first attachment unit (20) and the second attachment unit (22) comprise a respective disengaged state in which the device (10) is movable within the opening (12) of the wellhead (3) and a respective engaged state in which the first attachment unit (20) and the second attachment unit (22) engage with the respective upper portion (UP) and the lower portion (LP) of the wellhead (3).
5. The device (10) according to any of the previous claims, wherein the second attachment unit (22) comprises an expandable engagement member adapted to engage with an inner envelope surface of the opening (12) at the lower portion of the wellhead (3) when the second attachment unit (22) is in the engaged state.
6. The device (10) according to any of the previous claims, wherein the first attachment unit (20) comprises an expandable engagement member adapted to engage with an inner envelope surface of the opening (12) at the upper portion (UP) of the wellhead (3) when the first attachment unit (20) is in the engaged state.
7. The device (10) according to any of the previous claims, wherein the support structure (14) is elongated and the first attachment unit (20) and the second attachment unit (22) are spaced apart along a longitudinal axis of the support structure (14).
8. The device (10) according to any of the previous claims, wherein the displacement unit (30) comprises a motor unit (32) acting on the first attachment unit (20) and the second attachment unit (22) so that the first attachment unit (20) and the second attachment unit (22) are adapted to be displaced in respect to each other between a first spacing and a second spacing, wherein the second spacing is larger than the first spacing.
9. The device (10) according to any of the previous claims, wherein the device (10) comprises a cutting device (40) arranged at the support structure (14), which cutting device (40) is adapted to provide said cut (5) in the wellhead (3).
10. The device (10) according to any of the previous claims, wherein the cutting device (40) is arranged at an end part of the support structure (14).
11. The device (10) according to any of the previous claims, wherein the cutting device (40) is arranged between the first attachment unit (20) and the second attachment unit (22).
12. An arrangement (1) for operation on a wellhead (3) of a hydrocarbon well, the arrangement (1) comprises the device (10) according to any of claim 1-11 and a further displacement unit (50) for displacing the device (10) within the opening (12) of the wellhead (3).
13. The arrangement (1) according to claim 12, wherein the further displacement unit (50) comprises means (34) for determining the displacement of the device (10) within the opening (12) of the wellhead (3).
14. The arrangement (1) according to any of claim 12-13, wherein the arrangement (1) further comprises a guide arrangement (60) for positioning the arrangement (1) in a predetermined position in respect to the wellhead (3).
15. The arrangement (1) according to claim 14, wherein the arrangement (1) comprises a locking device (64) for locking the position of the arrangement (1) to the predetermined position in respect to the wellhead (3).
16. The arrangement (1) according to any of claim 12-15, wherein arrangement (1) comprises means (70) for control and power supply of the device (10) and the further displacement unit (50).
17. The arrangement (1) according to any of claim 12-16, wherein the arrangement (1) comprises a remotely operated vehicle (72) and said means (70) for control and power supply are provided in the remotely operated vehicle (72) connected to the device (10) and the further displacement unit (50).
18. A method for operation on a wellhead (3) of a hydrocarbon well by means of a device (10) according to claim 1-11, which wellhead (3) is provided with or is to be provided with a separating cut (5), the method comprises the steps of - setting the first attachment unit (20) and the second attachment unit (22) to the disengaged state, - arranging the device (10) in the opening (12) of the wellhead (3) so that the first attachment unit (20) is positioned at an upper portion (UP) of the wellhead (3) at an upper side of said cut (5) and the second attachment unit (22) is positioned at a lower portion (LP) of the wellhead (3) at a lower side of said cut (5) that is opposite to the upper side, - setting the first attachment unit (20) and the second attachment unit (22) to the engaged state, and - generating a force that acts to separate the first attachment unit (20) and the second attachment unit (22) from each other.
19. The method according to claim 18, wherein the method comprises - measuring a displacement of the first attachment unit (20) and the second attachment unit (22) in respect to each other, and - determining that a sufficient separating cut (5) exists if the displacement is equal or exceeding a predetermined distance.
20. The method according to any of claim 18-19, wherein the method comprises - arranging the device (10) in the opening (12) of the wellhead (3) so that the cutting device (40) is in a position for the intended cut (5), and - generating a cut (5) in the wellhead (3) by means of the cutting device (40).
21. The method according to any of claim 18-20, wherein the method comprises - after generating the cut (5), if necessary, rearranging the device (10) in the opening (12) of the wellhead (3) to a position where the first attachment unit (20) is positioned at an upper portion (UP) of the wellhead (3) at an upper side of said cut (5) and the second attachment unit (22) is positioned at a lower portion (LP) of the wellhead (3) at a lower side of the cut (5).
22. The method according to any of claim 18-21, wherein the method comprises - determining that an insufficient separating cut (5) exists if the measured displacement of the first attachment unit (20) and the second attachment unit (22) in respect to each other is less than a predetermined distance.
23. The method according to any of claim 18-22, wherein the method comprises - if an insufficient separating cut (5) has been determined, if necessary, rearranging the device (10) in the opening (12) of the wellhead (3) so that the cutting device (40) is in a position of the cut (5), and - continue cutting the wellhead (3) at the position of the cut (5).
NO20160767A 2016-05-06 2016-05-06 A device for operation on a wellhead of a hydrocarbon well NO20160767A1 (en)

Priority Applications (3)

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NO20160767A NO20160767A1 (en) 2016-05-06 2016-05-06 A device for operation on a wellhead of a hydrocarbon well
PCT/NO2017/050105 WO2017192043A1 (en) 2016-05-06 2017-05-03 A device for providing a separating cut in a material of a wellhead of a hydrocarbon well
PCT/NO2017/050107 WO2017192045A1 (en) 2016-05-06 2017-05-03 A device for operation on a wellhead of a hydrocarbon well

Applications Claiming Priority (1)

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NO20160767A NO20160767A1 (en) 2016-05-06 2016-05-06 A device for operation on a wellhead of a hydrocarbon well

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020060076A1 (en) * 2000-07-24 2002-05-23 Harrell Danny H. Abandonment and retrieval apparatus and method
US20130048273A1 (en) * 2011-08-31 2013-02-28 Baker Hughes Incorporated Resettable Lock for a Subterranean Tool
US20140027117A1 (en) * 2012-07-24 2014-01-30 Smith International, Inc. System and method of cutting and removing casings from wellbore

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO853939L (en) * 1984-10-06 1986-04-07 Deepwater Oil Services CUTTING AND RECOVERY TOOL
CA2036376C (en) * 1989-08-03 1998-08-18 Geoffrey Owen Rouse Apparatus for recovering a wellhead
GB9120298D0 (en) * 1991-09-24 1991-11-06 Homco International Inc Casing cutting and retrieving tool
AU761233B2 (en) * 1999-04-05 2003-05-29 Baker Hughes Incorporated One-trip casing cutting & removal apparatus
US7647980B2 (en) * 2006-08-29 2010-01-19 Schlumberger Technology Corporation Drillstring packer assembly
US9222328B2 (en) * 2012-12-07 2015-12-29 Smith International, Inc. Wellhead latch and removal systems
US9650853B2 (en) * 2015-01-26 2017-05-16 Baker Hughes Incorporated Downhole cutting and jacking system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020060076A1 (en) * 2000-07-24 2002-05-23 Harrell Danny H. Abandonment and retrieval apparatus and method
US20130048273A1 (en) * 2011-08-31 2013-02-28 Baker Hughes Incorporated Resettable Lock for a Subterranean Tool
US20140027117A1 (en) * 2012-07-24 2014-01-30 Smith International, Inc. System and method of cutting and removing casings from wellbore

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WO2017192043A1 (en) 2017-11-09

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