EP3938274B1 - Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin - Google Patents

Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin Download PDF

Info

Publication number
EP3938274B1
EP3938274B1 EP20713397.6A EP20713397A EP3938274B1 EP 3938274 B1 EP3938274 B1 EP 3938274B1 EP 20713397 A EP20713397 A EP 20713397A EP 3938274 B1 EP3938274 B1 EP 3938274B1
Authority
EP
European Patent Office
Prior art keywords
mobile working
working deck
heave
heave compensation
elevation
Prior art date
Legal status (The legal status 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 status listed.)
Active
Application number
EP20713397.6A
Other languages
German (de)
English (en)
Other versions
EP3938274A1 (fr
Inventor
Diederick Bernardus Wijning
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huisman Equipment BV
Original Assignee
Itrec BV
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 Itrec BV filed Critical Itrec BV
Publication of EP3938274A1 publication Critical patent/EP3938274A1/fr
Application granted granted Critical
Publication of EP3938274B1 publication Critical patent/EP3938274B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
    • E21B19/08—Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods
    • E21B19/09—Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods specially adapted for drilling underwater formations from a floating support using heave compensators supporting the drill string
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B35/00—Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
    • B63B35/44—Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices
    • B63B35/4413—Floating drilling platforms, e.g. carrying water-oil separating devices
    • 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
    • E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
    • E21B19/002—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables specially adapted for underwater drilling
    • E21B19/004—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables specially adapted for underwater drilling supporting a riser from a drilling or production platform
    • E21B19/006—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables specially adapted for underwater drilling supporting a riser from a drilling or production platform including heave compensators

Definitions

  • the present invention relates to an offshore system for performing subsea wellbore related activities, e.g. workover activities, well maintenance, installing an object on a subsea wellbore, drilling a subsea wellbore, etc. while the offshore system is subjected to heave motion due to waves.
  • subsea wellbore related activities e.g. workover activities, well maintenance, installing an object on a subsea wellbore, drilling a subsea wellbore, etc. while the offshore system is subjected to heave motion due to waves.
  • the present invention also relates to a vessel including an offshore system and methods that are performed using the vessel according to the invention.
  • offshore vessels that comprise:
  • the heave compensation system is also configured to provide heave compensation to a traveling block being part of a hoisting device allowing synchronous motion of the mobile working deck and the traveling block during operation.
  • heave compensation of the mobile working deck as disclosed in WO2016/062812 also introduces a safety hazard, namely, that the mobile working deck is subjected to a relatively big acceleration caused by the heave compensation system itself when the loads applied to the mobile working deck suddenly and unintentionally change.
  • a sudden and unintentional change is when the relatively heavy drill string that is initially supported by the mobile working deck is unintentionally but suddenly released, for instance when a clamp suddenly fails or a component, possibly in the drill string itself, loses structural integrity.
  • the tension inherently present in the heave compensation system may then launch the mobile working deck like a catapult as the tension in the heave compensation system cannot be lowered sufficiently quick to compensate for the sudden change in load to the mobile working deck.
  • the present invention provides an offshore system for performing subsea wellbore related activities, comprising:
  • the invention is based on the insight of the inventors that the previously combined functionality of the working deck compensators to elevate the mobile working deck and to apply heave compensation once elevated should be separated from each other thereby allowing to use the elevation system in case of a sudden change in load applied to the mobile working deck to lower or limit the acceleration of the mobile working deck and prevent or at least limit the damage to the mobile working deck or any other component of the offshore system or floating device the offshore system is positioned on.
  • the heave compensation system In the event that the heave compensation system is used to compensate the heave motion due to waves within the heave motion range and a downwardly directed load applied to the mobile working deck suddenly decreases, the heave compensation system will cause the mobile working deck to rapidly accelerate upwards and is not able to quickly counteract this acceleration.
  • the elevation system can be used to quickly lower the mobile working deck within the elevation motion range to counteract the acceleration thereby giving time to the heave compensation system to adjust to the new load situation and keep the acceleration within limits to avoid or minimize damage to the offshore system. The same applies in case an upwardly directed load is suddenly increased.
  • the heave compensation system in the event that the heave compensation system is used to compensate the heave motion due to waves within the heave motion range and an upwardly directed load applied to the mobile working deck suddenly decreases, the heave compensation system will cause the mobile working deck to rapidly accelerate downwards and is not able to quickly counteract this acceleration.
  • the elevation system can be used to quickly raise the mobile working deck within the elevation motion range to counteract the acceleration thereby giving time to the heave compensation system to adjust to the new load situation and keep the acceleration within limits to avoid or minimize damage to the offshore system. The same applies when a downwardly directed load is suddenly increased.
  • the overload protection method may be configured to only cope with one situation, for instance the situation that the mobile working deck is rapidly accelerated upwards due to the undesirably big acceleration, preferably because a downwardly directed load is suddenly decreased.
  • the overload protection system is configured to detect an undesirably big upwards acceleration of the mobile working deck, and the overload protection system is configured to control the elevation system such that the mobile working deck motion in the elevation motion range is downwards.
  • the heave compensation system includes one or more hydraulic heave compensators, wherein the elevation system includes one or more hydraulic devices, and wherein the one or more heave compensators of the heave compensation system are connected to the floating body and to the one or more hydraulic devices of the elevation system with the one or more hydraulic devices being connected to the mobile working deck, or the one or more hydraulic devices of the elevation system are connected to the floating body and to the one or more heave compensators of the heave compensation system with the one or more heave compensators being connected to the mobile working deck.
  • connected to in the above embodiment also means an indirect connection instead of a direct connection, but that in any way the one or more hydraulic heave compensators are arranged in series (operatively seen) with the one or more hydraulic devices between the floating body and the mobile working deck.
  • the above described embodiment does not require that the number of hydraulic heave compensators is equal to the number of hydraulic devices. It may well be possible, but it is also possible that there is a difference in number of compensators and devices.
  • one or more actuators are provided between the floating body and the mobile working deck, each actuator being formed by a heave compensator of the heave compensation system in series with a hydraulic device of the elevation system.
  • the actuator may be embodied as a stack formed by a heave compensator arranged on top of a hydraulic device or a hydraulic device arranged on top of a heave compensator, but in an alternative embodiment, each heave compensator of the heave compensation system comprises a hydraulic cylinder and a piston rod moveable within and extending from said hydraulic cylinder, wherein each hydraulic device of the elevation system comprises a hydraulic cylinder and a piston rod moveable within and extending from said hydraulic cylinder, and wherein the piston rod of the heave compensator forms the hydraulic cylinder of the hydraulic device.
  • the piston rod of the hydraulic device forms the hydraulic cylinder of a corresponding heave compensator is also envisaged.
  • each heave compensator of the heave compensation system comprises a hydraulic cylinder, a piston and a piston rod moveable within and extending from said hydraulic cylinder, said piston dividing a space inside the hydraulic cylinder in a cap side chamber and a piston rod side chamber, and wherein the overload protection system is configured to open at least one release valve to release hydraulic pressure from the cap side chamber of each heave compensator in the event of a detected undesirably big acceleration of the mobile working deck.
  • each hydraulic device of the elevation system comprises a hydraulic cylinder and a rod moveable within and extending from said hydraulic cylinder, wherein the hydraulic cylinder includes a pressure chamber for receiving pressurized hydraulic fluid to position the rod relative to the hydraulic cylinder, and wherein the overload protection system is configured to open at least one release valve to release hydraulic pressure from the pressure chamber of each hydraulic device in the event of a detected undesirably big acceleration of the mobile working deck. Releasing the hydraulic pressure results in lowering of the mobile working deck within the elevation motion range and is thus one of the examples of control of the elevation system in case of an undesirably big acceleration of the mobile working deck.
  • the offshore system further comprises a riser tensioning system adapted to connect a riser extending along the firing line between the subsea wellbore and the floating body, and a riser connecting system adapted to connect the riser to the mobile working deck, wherein the overload protection system is configured to detect the undesirably big acceleration of the mobile working deck in the riser connecting system.
  • the overload protection system comprises a cylinder in the riser connecting system, which is in fluid communication with a release valve of the elevation system, such that in case of an undesirably big acceleration of the mobile working deck, the cylinder will retract or extend and cause the release valve to open.
  • the invention also relates to a vessel comprising a floating body and an offshore system according to the invention, wherein the tower of the offshore system is positioned on the floating body.
  • the vessel may for instance be a semi-submersible.
  • the invention further relates to a method for performing subsea wellbore related activities using the above described vessel, comprising the following steps:
  • the mobile working deck supports a drill string, wherein the undesirably big acceleration is caused by the support of the drill string suddenly and undesirably failing.
  • a riser is connected to the mobile working deck during heave compensation, and wherein the undesirably big acceleration is detected at the location where the riser is connected to the mobile working deck.
  • the invention may also be summarized as an offshore system for performing subsea wellbore related activities, comprising:
  • Fig. 1 depicts a vessel 1, here of the semi-submersible type.
  • the vessel 1 comprises a floating body or hull 3 with a deckbox structure 3a having an upper or main deck 6 and a box bottom, one or more pontoons 3b, here two parallel pontoons, and multiple, here four, support columns 3c extending upward from the one or more pontoons 3b and supporting thereon the deckbox structure 3a.
  • a moonpool 4 that extends through the deckbox structure 3a up to the main deck 6 of the deckbox structure.
  • the height of the deckbox structure 3a between the main deck 6 and the box bottom is between 11 and 15 meters, e.g. about 12.5 meters.
  • the vessel 1 comprises an offshore system with a tower 30 erected above the main deck 6, here of the deckbox structure 3a, and adapted to perform subsea wellbore related activities along at least one firing line 9 of the offshore system that vertically extends through the moonpool 4 into the sea.
  • the mentioned wellbore related activities may include workover activities, well maintenance, installing an object on a subsea wellbore, drilling a subsea wellbore, etc.
  • the tower 30 is provided with a crown block 31 at the top thereof and a travelling block 32 is suspended from the crown block 31 in a multiple fall arrangement of a cable 33.
  • the cable is connected to one or more winches allowing the travelling block 32 to be moved up and down along an operative side of the tower 30 and in the firing line 9, so generally in a range above the main deck 6.
  • the travelling block 32 for example, carries a topdrive 34 adapted for rotary drive of a drill string that is suspended from the topdrive and extends into a subsea wellbore.
  • the travelling block 32 is coupled to a trolley 35 that travels up and down along one or more vertical rails 36 provided on the tower 30.
  • the vessel 1 is further provided with a winch system comprising a hoisting winch and a hoisting cable 12 connected to the hoisting winch.
  • a travelling hoist block 13 distinct from the travelling block 32, is able to travel up and down along a side of the tower 30, and is supported by the hoisting cable 12.
  • the block 13 may be used for connecting with an object to be lowered to, or lifted from, the seafloor. Therefore, the length of the cable 12 is sufficient to reach the seafloor.
  • the cable 12 is arranged in a single fall arrangement, so with hoist block 13 at the end thereof as shown in Fig. 1 .
  • the block 13 has at least one sheave around which the cable 12 passes.
  • the cable 12 may have a terminal end that is embodied as a dead end.
  • the cable 12 is connected at either end thereof to a winch, e.g. to allow for increase speed and/or redundancy.
  • one end of the cable is connected to a winch and the other end to a heave motion compensation system.
  • the cable 12 is a synthetic fibre rope.
  • the tower 30 here is provided with a top sheave 37 from which the cable 12 is suspended in the firing line 9.
  • the top sheave 37 may be arranged in proximity of the crown block 31 or even combined therewith
  • the vessel 1 is provided with a mobile working deck 15 that is moveable with respect to the tower along the firing line within a motion range which will be elucidated in more detail below.
  • the mobile working deck 15 has a working deck surface, which working deck in a lowered position covers the moonpool 4, and which working deck surface in the lowered position of the mobile working deck 15 is preferably level with the main deck 6.
  • the mobile working deck 15 is supported by a heave compensation system being adapted to provide heave compensation of the mobile working deck within a heave compensation motion range, and an elevation system being adapted to position the mobile working deck within the elevation motion range, wherein the heave compensation system and the elevation system are arranged such that a position of the mobile working within the motion range is the sum of the position of the mobile working deck within the elevation motion range and the position of the mobile working deck within the heave compensation motion range.
  • the motion range is the sum of the elevation motion range and the heave compensation motion range.
  • the elevation system can be used to raise the mobile working deck 15 from the lower stationary position and to bring the mobile working deck 15 at a level where the heave compensation range is positioned above the lower stationary position allowing heave compensation without the risk of a collision with the main deck 6.
  • the heave compensation system may further be adapted to provide heave compensation for the cable 33 to provide a heave compensated motion of the travelling block 32 and thus of any drill string or the like suspended from the topdrive 35 during a drilling operation.
  • the heave compensation may be active and/or passive, and may include one or more sheave compensators each supporting one or more cable sheaves that engage the cable from which the travelling block is suspended.
  • the heave compensation may also, alternatively or in combination with sheave compensator(s), act directly on the winch(es), e.g. an active heave compensation control via a variable frequency electric drive of the winch(es).
  • the heave compensation system is able to effect a heave compensating motion of the mobile working deck within the heave compensation motion range synchronized with the heave compensation of the travelling block 32 that travels along a side of the tower 30.
  • the mobile working deck 15 (see figure 1 ) is envisaged for use as a stationary drill floor covering the moonpool 4 and generally level with the adjoining deck 6 of the hull.
  • the mobile working deck 15 may be provided with a personnel access platform supported underneath the mobile working deck 15 that facilitates access to equipment underneath the mobile working deck 15 during operations.
  • the vessel 1 is provided with a drilling tubulars storage rack 120 that is mounted on the hull 3, e.g. the deckbox structure, e.g. multi-joint drill pipe stands storage rack, e.g. a rotary storage rack.
  • the drilling tubulars storage rack is adapted for storage of drilling tubulars in vertical orientation therein.
  • the vessel, e.g. the mast structure 30, is provided with a racker system that is adapted to move a drilling tubular between the storage rack and a position aligned with the firing line.
  • the racker system is heave compensated and is configured to bring a drilling tubular removed from the storage rack in a heave compensation motion that is synchronized with the heave compensation motion of the mobile working deck 15.
  • the racker comprises a vertical motion arm assemblies rail, wherein at least one, e.g. multiple, motion arm assembly 125 is mounted on said vertical motion arm assemblies rail, each motion arm assembly having a base that is vertically mobile along said vertical motion arm assemblies rail by a drive configured to provide said heave compensation motion that is synchronized with the heave compensation motion of the mobile working deck.
  • each motion arm assembly 125 further having an extensible, e.g.
  • telescopic, arm that is mounted via a vertical axis slew bearing on said base so as to allow for extension and retraction of said arm as well as slewing motion of said telescopic arm about said vertical slew axis, wherein said arm is adapted to support a tubulars gripper tool at an end of said arm, so as to allow for gripping of a drilling tubulars by means of the tubular gripper tool.
  • Fig. 2 schematically depicts a cross-sectional view of the mobile working deck 15 of Fig. 1 with the working deck surface indicated by reference numeral 16.
  • Fig. 2 depicts the situation that a diverter 110 is supported on the underside of the mobile working deck 15 and a riser 115 is connected to the diverter 110.
  • the diverter 110 is configured to divert a hydrocarbon and/or drilling mud stream from a subsea wellbore to the vessel.
  • a hose or pipe connects the diverter to a mud handling facility onboard the vessel 1, e.g. located within the deckbox structure 3a.
  • slip device 20 having for instance mobile clamping jaws, which slip device 20 is configured to support a suspended drill string 130 or the like.
  • the mobile working deck 15 supports a riser spider device configured to support a suspended riser, e.g. during assembly and disassembly of a riser.
  • the riser spider device has radially moveable dogs that engage underneath a flange of a riser joint to support the weight of the riser string.
  • the vessel 1 of Fig. 1 allows for performing of drilling activities wherein the heave compensated mobile working deck 15 rests on the top of the rigid riser that extends down to a subsea well.
  • the hull 3, here in the deckbox structure 3a adjoining the moonpool 4, comprises one or more wireline riser tensioner equipment rooms accommodating therein wireline riser tensioner equipment, e.g. comprising vertically oriented wireline riser tensioner cylinders.
  • This equipment is configured to provide top tension to the riser 115 that extends along the firing line between the seafloor and the vessel 1.
  • the diverter 110 is connected to the mobile working deck 15 via a connecting structure 140.
  • This connecting structure 140 may for instance include cylinders 145 operatively connected at one end to the diverter 110 and with the opposite end to the mobile working deck 15.
  • the connecting structure 140 may provide an additional tension to the riser 115 albeit that in a practical embodiment, this additional tension may be relatively small compared to the tension applied to the riser using the aforementioned wireline riser tensioner equipment.
  • Fig. 2 depicts an embodiment thereof. Shown are two hydraulic actuators 150, but a practical embodiment may include any number of such hydraulic actuators, e.g. 1, 3, 4 or more hydraulic actuators 150 depending on the demands, available space, etc.
  • the hydraulic actuators 150 are thus provided between the floating body, i.e. the hull 3, and the mobile working deck 15.
  • Each hydraulic actuator 150 comprises a hydraulic compensator 151 connected to the hull 3 and a hydraulic device 152 arranged between the hydraulic compensator 151 and the mobile working deck 15.
  • the hydraulic compensator 151 is part of the heave compensation system allowing heave compensation in a heave compensation motion range indicated by the stroke ST1 of the hydraulic compensator 151.
  • the hydraulic device 152 is part of the elevation system allowing to position the mobile working deck 15 in an elevation motion range indicated by the stroke ST2 of the hydraulic device 152.
  • the heave compensation system and the elevation system are arranged in series, so that the position of the mobile working deck 15 in its motion range is determined by the sum of the relative position Z1 within the heave compensation motion range and the relative position Z2 within the elevation motion range.
  • the heave compensation motion range may be 5-10 meters, e.g. about 7.5 meters
  • the elevation motion range may be 4-8 meters, e.g. about 6 meters, so that the motion range of the mobile working deck 15 may be 9-18 meters, e.g. about 13.5 meters.
  • the hydraulic compensator 151 is configured as a double-acting compensator allowing to actively move in both directions, i.e. up and down, to achieve the desired heave motion compensation speeds in both directions.
  • the hydraulic compensator 151 includes a hydraulic cylinder 151a, a piston 151b, and a piston rod 151c connected to the piston 151b and being moveable within and extending from the hydraulic cylinder 151a.
  • the piston 151b divides a space inside the hydraulic cylinder 151a in a cap side chamber 151d and a piston rod side chamber 151e. Forcing hydraulic liquid in the cap side chamber 151d and letting hydraulic liquid simultaneously be allowed to leave the piston rod side chamber 151e will actively extend the hydraulic compensator 151. Forcing hydraulic liquid in the piston rod side chamber 151e and letting hydraulic liquid simultaneously be allowed to leave the cap side chamber 151d will actively retract the hydraulic compensator 151.
  • the hydraulic device 152 is configured as a single-acting device allowing to actively extend the device, but passively retract the device using gravitational forces or other downwardly directed loads. As the hydraulic device 152 is used to elevate the mobile working deck 15, a double-acting device can be used, but is not necessary per se.
  • the hydraulic device 152 includes a hydraulic cylinder 152a and a piston rod 152b being moveable within and extending from the hydraulic cylinder 152a.
  • the piston rod 152b and the hydraulic cylinder 152a delimit a space 152c.
  • Forcing hydraulic liquid in the space 152c will actively extend the hydraulic device 152.
  • gravitational forces acting on the hydraulic device e.g. the weight of the mobile working deck and any loads applied thereon, will push hydraulic liquid out of the space 152c thereby allowing to passively retract the hydraulic device 152.
  • the mobile working deck 15 is in an elevated position Z2 within the elevation motion range allowing to heave compensate the mobile working deck within the heave compensation motion range.
  • the main load applied to the mobile working deck 15 is the weight of the drill string 130 supported by slip device 20.
  • the hydraulic compensator 151 has more or less the behaviour of a spring, which spring has to provide a sufficiently large upwardly directed spring force to the mobile working deck to counteract the weight and loads applied to the mobile working deck 15.
  • the weight, i.e. the loads, applied to the mobile working deck 15 suddenly decreases significantly.
  • the hydraulic compensator 151 which is acting like a spring, will tend to launch the mobile working deck 15 by applying a relatively large acceleration to the mobile working deck 15 caused by the spring force applied to the mobile working deck 15 by the heave compensation system.
  • the applied spring force of the hydraulic compensator cannot be lowered sufficiently quick to prevent the launch of the mobile working deck 15. Whether the mobile working deck will actually be launched is not of relevance, because the damage caused by the relatively large acceleration of the mobile working deck and subsequent impact with other components of the offshore system, e.g. the tower, is similarly undesired.
  • the offshore system in Figs. 1 and 2 includes an overload protection system.
  • the function of the overload protection system is to prevent or minimize damage to the offshore system.
  • the overload protection system is therefore configured to detect an undesirably big acceleration of the mobile working deck.
  • an undesirably big acceleration of the mobile working deck is detected in the cylinders 145 of the connecting structure 140 between the diverter 110 and the riser 115.
  • the mobile working deck 15 When an undesirably big acceleration of the mobile working deck occurs, the mobile working deck 15 will start to move upwards relative to the riser string 115 causing the cylinders 145 to retract.
  • the retraction of the cylinders 145 or an associated pressure increase (or decrease) in a chamber in the cylinders may be used to detect the undesirably big acceleration.
  • any other detection principle may alternatively or additionally be used, e.g. using a dedicated detection system with one or more detectors or sensors. Examples thereof are:
  • the cylinders 145 are in this embodiment hydraulically connected (see dashed lines) to release valves 170 arranged on the respective hydraulic devices 152 of the elevation system.
  • the cylinders 145 will retract, so that the increase in hydraulic pressure in the cylinders 145 will cause the release valves 170 to open allowing hydraulic liquid to escape from the spaces 152c caused by the upwardly moving hydraulic cylinder 152a and the mass inertia of the mobile working deck 15.
  • the result is that the mobile working deck moves downwards in the elevation motion range, i.e. the Z2 value decreases, while the motion in the heave compensation motion range is upwards, i.e. the Z1 value increases, such that the overall acceleration of the mobile working deck 15 is lowered or at least limited preventing or at least minimizing the damage caused by undesired motion of the mobile working deck 15.
  • the above embodiment describes a passive overload protection system.
  • the cylinders 145 and release valves 170 may operate without requiring any active input or power, so that in substantially all situations the overload protection system may function.
  • the overload protection system is an active system or a combination of active and passive components.
  • the overload protection system may comprise a detection system configured to detect an undesirably big acceleration of the mobile working deck, e.g. using detectors and/or sensors, and/or may comprise a control system to control the elevation system and/or the heave compensation system in dependence of an output of the detection system.
  • such a detection system and control system may be present such that the detection system detects movement of the working deck relative to the diverter 110 or by measuring the pressure inside the cylinders 145 and the control system may be connected to the heave compensation system, e.g. release valves in fluid communication with the cap side chambers 151d of the heave compensators 151 to release hydraulic pressure in these chambers quickly reducing the spring force applied by the heave compensators 151 to the mobile working deck 15 to further reduce and/or limit the acceleration applied to the mobile working deck 15 in addition to the passive overload protection system part.
  • the cylinders 145 may also be connected to the release valves of the heave compensators 151 in a passive manner similar to the release valves 170.
  • heave compensation system and the elevation system are arranged in series by arranging the respective heave compensators and hydraulic devices in series and combining a heave compensator 151 and a hydraulic device 152 into one actuator 150.
  • Fig. 3 schematically depicts the mobile working deck 15 of the vessel of Fig. 1 supported by a heave compensation system HCS and an elevation system ES according to another embodiment of the invention.
  • the heave compensation system HCS and the elevation system ES are arranged in series, seen in vertical direction. Shown are two heave compensators 151 as part of the heave compensation system HCS and arranged between the floating body, hull 3 in Fig. 1 , and an intermediate member IM.
  • the elevation system ES comprises a hydraulic device 152 arranged between the intermediate member IM and the mobile working deck 15. Hence, one hydraulic device 152 is used per two heave compensators 151.
  • the offshore system may for instance comprise two configurations as shown in Fig. 3 at opposite sides of the moonpool.

Landscapes

  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Fluid Mechanics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Earth Drilling (AREA)

Claims (12)

  1. Système en mer pour l'exécution d'activités associées à un puits de forage sous-marin, comprenant :
    une tour destinée à être positionnée sur un corps flottant (3) et définissant une ligne de tir (9) sensiblement verticale le long de la tour ;
    un pont de travail mobile (15) qui est mobile par rapport à la tour le long de la ligne de tir dans une plage de mouvement qui est la somme d'une plage de mouvement d'élévation et d'une plage de mouvement de compensation de pilonnement ;
    un système de compensation de pilonnement qui est adapté pour réaliser la compensation de pilonnement du pont de travail mobile dans la plage de mouvement de compensation de pilonnement ; et
    un système d'élévation qui est adapté pour positionner le pont de travail mobile dans la plage de mouvement d'élévation,
    caractérisé en ce que :
    le système en mer comprend en outre un système de protection contre les surcharges configuré pour détecter une accélération excessivement forte du pont de travail mobile (15),
    et dans lequel le système de protection contre les surcharges, dans le cas d'une accélération excessivement forte détectée du pont de travail mobile (15), est configuré pour contrôler le système d'élévation de sorte que le mouvement du pont de travail mobile dans la plage de mouvement d'élévation est opposé au mouvement de pont de travail mobile dans la plage de mouvement de compensation de pilonnement afin de réduire ou de limiter l'accélération du pont de travail mobile (15).
  2. Système en mer selon la revendication 1, dans lequel le système de compensation de pilonnement comprend un ou plusieurs compensateurs de pilonnement hydrauliques, dans lequel le système d'élévation comprend un ou plusieurs dispositifs hydrauliques, et dans lequel les un ou plusieurs compensateurs de pilonnement du système de compensation de pilonnement sont raccordés au corps flottant et aux un ou plusieurs dispositifs hydrauliques du système d'élévation avec les un ou plusieurs dispositifs hydrauliques qui sont raccordés au pont de travail mobile, ou les un ou plusieurs dispositifs hydrauliques du système d'élévation sont raccordés au corps flottant et aux un ou plusieurs compensateurs de pilonnement du système de compensation de pilonnement avec les un ou plusieurs compensateurs de pilonnement qui sont raccordés au pont de travail mobile.
  3. Système en mer selon la revendication 2, dans lequel un ou plusieurs actionneurs sont prévus entre le corps flottant et le pont de travail mobile, chaque actionneur étant formé par un compensateur de pilonnement du système de compensation de pilonnement en série avec un dispositif hydraulique du système d'élévation.
  4. Système en mer selon la revendication 3, dans lequel chaque compensateur de pilonnement du système de compensation de pilonnement comprend un cylindre hydraulique et une tige de piston mobile dans et s'étendant à partir dudit cylindre hydraulique, dans lequel chaque dispositif hydraulique du système d'élévation comprend un cylindre hydraulique et une tige de piston mobile dans et s'étendant à partir dudit cylindre hydraulique, et dans lequel la tige de piston du compensateur de pilonnement forme le cylindre hydraulique du dispositif hydraulique.
  5. Système en mer selon la revendication 2, dans lequel chaque compensateur de pilonnement du système de compensation de pilonnement comprend un cylindre hydraulique, un piston et une tige de piston mobile dans et s'étendant à partir dudit cylindre hydraulique, ledit piston divisant un espace à l'intérieur du cylindre hydraulique en une chambre du côté du capuchon et en une chambre du côté de la tige de piston, et dans lequel le système de protection contre les surcharges est configuré pour ouvrir au moins une soupape de décharge pour libérer la pression hydraulique de la chambre du côté du capuchon de chaque compensateur de pilonnement dans le cas d'une accélération excessivement forte détectée du pont de travail mobile.
  6. Système en mer selon la revendication 2, dans lequel chaque dispositif hydraulique du système d'élévation comprend un cylindre hydraulique et une tige mobile dans et s'étendant à partir dudit cylindre hydraulique, dans lequel le cylindre hydraulique comprend une chambre de pression pour recevoir le fluide hydraulique sous pression afin de positionner la tige par rapport au cylindre hydraulique, et dans lequel le système de commande est configuré pour ouvrir au moins une soupape de décharge afin de libérer la pression hydraulique de la chambre de pression de chaque dispositif hydraulique dans le cas d'une accélération excessivement forte détectée du pont de travail mobile.
  7. Système en mer selon l'une quelconque des revendications 1 à 6, comprenant en outre un système de tension de tube prolongateur adapté pour raccorder un tube prolongateur s'étendant le long de la ligne de tir entre le puits de forage sous-marin et le corps flottant, et un système de raccordement de tube prolongateur adapté pour raccorder le tube prolongateur au pont de travail mobile, dans lequel le système de détection est prévu dans le système de raccordement de tube prolongateur.
  8. Navire comprenant un corps flottant et un système en mer selon l'une quelconque des revendications 1 à 7, dans lequel la tour du système en mer est positionnée sur le corps flottant.
  9. Navire selon la revendication 8, dans lequel le navire est un semi-submersible.
  10. Procédé d'exécution d'activités associées à un puits de forage sous-marin à l'aide d'un navire selon la revendication 8 ou 9, comprenant les étapes suivantes consistant à :
    a. positionner le pont de travail mobile dans la plage de mouvement d'élévation à l'aide du système d'élévation pour permettre la compensation de pilonnement du pont de travail mobile ;
    b. prévoir la compensation de pilonnement du pont de travail mobile à l'aide du système de compensation de pilonnement ; et
    c. dans le cas dans lequel une accélération excessivement forte du pont de travail mobile est détectée, commander le système d'élévation de sorte que le mouvement du pont de travail mobile dans la plage de mouvement d'élévation est opposé au mouvement du pont de travail mobile dans la plage de mouvement de compensation de pilonnement afin de réduire ou de limiter l'accélération du pont de travail mobile.
  11. Procédé selon la revendication 10, dans lequel pendant la compensation de pilonnement, le pont de travail mobile supporte une garniture de forage, et dans lequel l'accélération excessivement forte est provoquée par la défaillance soudaine et indésirable du support de la garniture de forage.
  12. Procédé selon la revendication 10 ou 11, dans lequel un tube prolongateur est raccordé au pont de travail mobile pendant la compensation de pilonnement, et dans lequel l'accélération excessivement forte est détectée à l'emplacement où le tube prolongateur est raccordé au pont de travail mobile.
EP20713397.6A 2019-03-12 2020-03-11 Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin Active EP3938274B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL2022729A NL2022729B1 (en) 2019-03-12 2019-03-12 Offshore system, vessel and method for performing subsea wellbore related activities
PCT/NL2020/050162 WO2020185083A1 (fr) 2019-03-12 2020-03-11 Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin

Publications (2)

Publication Number Publication Date
EP3938274A1 EP3938274A1 (fr) 2022-01-19
EP3938274B1 true EP3938274B1 (fr) 2023-06-07

Family

ID=66380087

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20713397.6A Active EP3938274B1 (fr) 2019-03-12 2020-03-11 Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin

Country Status (4)

Country Link
EP (1) EP3938274B1 (fr)
CN (1) CN113784887B (fr)
NL (1) NL2022729B1 (fr)
WO (1) WO2020185083A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL2022729B1 (en) * 2019-03-12 2020-09-18 Itrec Bv Offshore system, vessel and method for performing subsea wellbore related activities

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL2022729B1 (en) * 2019-03-12 2020-09-18 Itrec Bv Offshore system, vessel and method for performing subsea wellbore related activities

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1103459A1 (fr) * 1999-11-24 2001-05-30 Mercur Slimhole Drilling and Intervention AS Arrangement pour la compensation des mouvements de levée et de marée
CN2642669Y (zh) * 2003-09-18 2004-09-22 袁晓纪 可下潜的水上浮动机场
WO2007145503A1 (fr) * 2006-06-16 2007-12-21 Itrec B.V. Compensation du mouvement de tangage
JP2009280960A (ja) * 2008-05-19 2009-12-03 Tokai Univ 揚水機構および水底資源回収装置
DK178120B1 (en) * 2013-04-18 2015-06-01 A P Møller Mærsk As An Offshore Floating Vessel and a Method of Operating the Same
CN104276256A (zh) * 2013-07-02 2015-01-14 吕武轩 甲板水平姿态自动保持系统
AU2014221196B2 (en) * 2014-09-02 2016-07-07 Icon Engineering Pty Ltd Coiled tubing lift frame assembly and method of use thereof
GB201418377D0 (en) * 2014-10-16 2014-12-03 Expro North Sea Ltd Landing string retainer system
NL2013680B1 (en) 2014-10-24 2016-10-05 Itrec Bv Offshore drilling system, vessel and method.
EP3342699B1 (fr) * 2016-12-27 2020-03-11 Nautilus Floating Solutions, SL Plate-forme flottante de forage en mer
CN108045516B (zh) * 2017-12-04 2020-08-28 浙江海洋大学 海上平台

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL2022729B1 (en) * 2019-03-12 2020-09-18 Itrec Bv Offshore system, vessel and method for performing subsea wellbore related activities

Also Published As

Publication number Publication date
WO2020185083A1 (fr) 2020-09-17
CN113784887A (zh) 2021-12-10
EP3938274A1 (fr) 2022-01-19
NL2022729B1 (en) 2020-09-18
CN113784887B (zh) 2023-11-21

Similar Documents

Publication Publication Date Title
US6988459B2 (en) Multipurpose tower for monohull with moveable hatch
EP2847417B1 (fr) Navire en mer et procédé de fonctionnement d'un tel navire en mer
US9624739B2 (en) Drilling rig
NL2023277B1 (en) Retrofitting an existing offshore drilling vessel
EP3710351B1 (fr) Navire et procédé d'exécution d'activités associées à un puits de forage sous-marin
US11377913B2 (en) Offshore drilling rig comprising an anti-recoil system
EP3938274B1 (fr) Système en mer, navire et procédé d'exécution d'activités associées à un puits de forage sous-marin
WO2017050336A1 (fr) Navire de forage en mer
US20150104275A1 (en) Lifting Apparatus
NL2024928B1 (en) Offshore drilling vessel and installation for performing subsea wellbore related activities.
EP3755618B1 (fr) Navire et procédé pour effectuer des activités associées à un puits sous-marin, par exemple des activités de reconditionnement, une maintenance de puits, l'installation d'un objet sur un puits de forage sous-marin
CN114245784B (zh) 海上钻井系统、船和方法
NL2011873C2 (en) Motion compensation system, hoisting device, floating marine structure, fixed marine structure.
NL2023601B1 (en) Semi-submersible floating offshore vessel
EP3513106B1 (fr) Système, appareil et procédé
WO2024068366A1 (fr) Navire de forage en mer et installation servant à réaliser des activités associées à un puits de forage sous-marin
OA19498A (en) Offshore drilling rig comprising an antirecoil system

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20211012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
REG Reference to a national code

Ref country code: DE

Ref legal event code: R079

Ref document number: 602020011952

Country of ref document: DE

Free format text: PREVIOUS MAIN CLASS: B63B0035440000

Ipc: E21B0019090000

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

RIC1 Information provided on ipc code assigned before grant

Ipc: E21B 19/09 20060101AFI20220908BHEP

INTG Intention to grant announced

Effective date: 20221007

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: AT

Ref legal event code: REF

Ref document number: 1575647

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230615

Ref country code: DE

Ref legal event code: R096

Ref document number: 602020011952

Country of ref document: DE

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20230607

REG Reference to a national code

Ref country code: NO

Ref legal event code: T2

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1575647

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230908

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231007

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231009

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231007

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602020011952

Country of ref document: DE

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20240322

Year of fee payment: 5

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

26N No opposition filed

Effective date: 20240308

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NO

Payment date: 20240227

Year of fee payment: 5