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
  • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
  • E21B43/01—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells specially adapted for obtaining from 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
  • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
  • E21B43/01—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells specially adapted for obtaining from underwater installations
  • E21B43/0107—Connecting of flow lines to offshore structures
• • 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
  • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
  • E21B17/01—Risers
• • 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

Definitions

• the present invention generally relates to the field of bottom-surface connections of the type comprising a vertical submarine pipe, called riser, connecting the bottom of the sea to a floating support installed on the surface.
• This floating support generally comprises anchoring means to remain in position despite the effects of currents, winds and swells. In general, it also includes means for storing and processing petroleum as well as means for unloading towards tanker removers. The latter appear at regular intervals to carry out the removal of production.
• the name of these floating barge type supports is the English term "Floating Production Storage Offloading" (meaning “floating means of storage, production and unloading") hereinafter abbreviated as "FPSO”.
• FPSO Floating Production Storage Offloading
• the well heads are often distributed over the entire field and the production pipes, as well as the water injection lines and the control cables, are laid on the sea floor towards a fixed location , vertically from which the floating support is positioned on the surface.
• Some wells are located vertical to the floating support and the interior of the well is then accessible directly from the surface.
• the well head fitted with its "Christmas tree" can be installed on the surface, on board the floating support. We can then perform, from a derrick installed on said floating support, all drilling operations, production and maintenance of the well throughout the life of the well. This is known as a dry wellhead.
• the dry well heads are gathered in a limited area of the platform, in which the derrick is movable to come to be positioned vertically over each of the wells to carry out drilling operations or operations well maintenance throughout the life of the field.
• the drilling derrick is a very high structure which can reach 60m and which has a lifting capacity which can exceed 500 tonnes, the means necessary to move it from one well to another and to keep it in position during operations on the wells lead to complex and expensive structures.
• the SPARS and TLPs are also equipped with a multiplicity of risers subtended by floats and held in position by guidance systems.
• risers rise to the surface in a central cavity of the floating support called "wellbay” or drilling bay.
• the cavity crosses the hull vertically right through on a height of about thirty meters, with a draft of about twenty meters; it is generally installed at the floating support axis, equidistant from its ends, because it is the zone where the amplitudes of the movements and accelerations is the lowest when the ship is subjected to the phenomena of roll, pitch and lace.
• Buoyancy elements of the "can" type are used, installed at various levels on the risers connecting the surface to the ultra deep seabed (1000-3000m).
• the floats concerned are large with in particular a diameter greater than 5m, and a length of 10 to 20m and have unitary buoyancies of up to 100 tonnes.
• the float and the pipe are subjected to the effects of the swell, of the current, but being connected to the FPSO on the surface, are also indirectly subjected to the effects of the wind. This results in significant lateral and vertical movements, up to several meters, of the riser-float-barge assembly, especially in the area prone to swell.
• risers are spaced from each other by several meters and also by several meters from the walls of the wellbay, which leads to wellbays which can reach 80 m in length and 20 m in width, on FPSO barges measuring up to 350 m in length, 80 m in width and having a height at the level of the plating which may reach and exceed 35 m.
• FPSO barges measuring up to 350 m in length, 80 m in width and having a height at the level of the plating which may reach and exceed 35 m.
• Such barges have a deadweight tonnage of up to and over 500,000 DWT.
• the present invention relates to the guidance of risers within the generally central cavity in the production position or in a position where drilling operations as well as heavy well maintenance operations are carried out, that is to say from of a fixed derrick compared to the floating support, or else to the means for transferring the riser between these various positions.
• the present invention also relates to the transfer of risers within the generally central cavity from their production position to a position where drilling operations as well as heavy well maintenance operations are carried out, that is to say from a fixed derrick relative to the floating support.
• drilling riser The drilling of the well is carried out at the main axis of the derrick, through a riser called “drilling riser", the function of which is to guide the drilling rods and to contain the mud in return of the well being drilled.
• This drilling riser is assembled from unit lengths up to 50m, the assembly being lowered step by step, as and when said riser is assembled.
• the part of the riser corresponding to the slice of water is disconnected from the well at sea level, then is directed towards a garage position after its length has been shortened by disassembly of one or more two unit lengths. By doing so, the drilling riser remains hanging, its lower end being located 50-100 m from the bottom.
• the production riser can then be assembled in the same way step by step until it reaches the entrance to the well.
• the floats are installed in the upper part as they are laid, then the base of the production riser is finally connected to the well.
• the well is then equipped with various production casings and the "Christmas tree" of the dry well head is put in place.
• the assembly is then transferred to its "slot", production position where it will remain throughout the life of the field, except for certain maintenance operations where it will be necessary to bring said riser to the main axis of the derrick to perform heavy operations.
• An object of the present invention is to provide a device for holding and guiding a riser, in particular a floating riser, with respect to the floating support, which is simple to implement and which can be useful whatever the position of the riser. , especially when the riser is in its production position or in the drilling or maintenance position on the axis of the derrick; or during the transfer of the riser from its production position to the axis of the derrick.
• This device must allow relative movements of the floating support and the riser, so as to withstand current fatigue forces corresponding to lateral loads of up to 10 tonnes, and occasional extreme forces corresponding to loads of up to 100 tonnes, even 200 Tons.
• the device must be able to authorize not only substantially vertical longitudinal displacements of up to 5 meters, if only relative movements between the floating support and the risers are considered in normal operating mode, but also to accept the corresponding extreme displacements. .the complete deballasting of the floating support or its maximum ballasting, which then corresponds to a total stroke of up to 15 to 20 meters.
• the riser must remain substantially coaxial with the axis of the derrick.
• Another object of the present invention is to provide a riser holding and guiding device in the production position which resists wear over a long period, in particular over several years.
• Another object of the present invention is to provide a guiding device which allows transfers of the riser from one position to another within the central cavity (wellbay) to be simple to perform and therefore can be carried out in complete safety.
• the present invention provides a device for holding and guiding a riser, in particular a floating riser, relative to a floating support comprising guide means allowing the sliding of said riser along its longitudinal axis and guiding its movements. lateral in a horizontal plane perpendicular to said longitudinal axis of the riser, in particular in a radial direction.
• the device according to the invention comprises articulation means integral with said floating support allowing: a) the rotation of said riser about a horizontal axis perpendicular to the longitudinal axis of said riser, within the limit of a half-angle cone at the apex less than or equal to 10 °, said horizontal axis and said apex of the cone being located substantially in the center of the riser and at the median plane of the zone where said articulation means are located along the longitudinal axis, and b) said sliding of said riser along its longitudinal axis and said guide of the lateral displacements of said riser in a plane substantially perpendicular to said longitudinal axis of the riser, and said articulation means comprise:
• first friction pads being mounted on a pad support allowing the pivoting of said pads around an axis perpendicular to said longitudinal axis of said riser
• said first pads cooperating with second friction pads, or preferably rollers, so that said second pads or said rollers are supported on said riser, and allow its sliding, and said riser comes to bear on said first pads only when said second pads or said rollers move under the effect of lateral movements of said riser. It is understood that the lateral movements of the riser, in particular in a radial direction, are generated by the relative forces between floating support and riser.
• longitudinal axis of the riser is meant the vertical axis when the riser is in the rest position, that is to say not subject to movements related to the agitation of the sea.
• said second pads or said rollers are in permanent support on the riser, but do not take up all of the load applied by the riser.
• the device according to the invention is in fact designed to withstand variable forces in the horizontal plane with at least two different levels of friction and wear.
• said first pads are set back from said second pads or said rollers.
• Said second pads or the rollers preferably provide guidance for the riser subjected to current forces of low loads of around 10 tonnes.
• Said first pads return to function and provide guidance when the riser is subjected to high loads under extreme conditions of implementation, in particular up to 100 tonnes, or even 200 tonnes, and when said second pads or said rollers are moved radially. under the effect of its heavy loads.
• This double level of friction and wear of the shoes and rollers makes the holding and guiding device of the invention particularly suitable when the riser is in the production position, that is to say in the case where the duration d operation requires wear-resistant guidance systems over a long period of time.
• Said first pads have a bearing surface on said riser which preferably has a curvature complementary to that of the riser.
• said first pads can pivot relative to an axis integral with said pad support.
• said pads are fixed relative to said pad support and said pad support can pivot by relative to said floating support to allow said pivoting of said first pads around an axis perpendicular to said longitudinal axis of said riser.
• said first pads are fixed to a tubular element enveloping said riser coaxially with said riser, said tubular member being mounted on a ball joint allowing said pivoting and said rotation of said pads and said riser respectively.
• said ball joint can be a laminated stop inside which said tubular element is embedded.
• said second pads or preferably said rollers are mounted on axes perpendicular to the vertical axis of said riser, the axis of said second pads or preferably said rollers being capable of moving in translation along an axis perpendicular to the axis longitudinal of said riser, in a radial direction.
• said first pads are distributed symmetrically around said riser, and comprise at least three pads located, more preferably, at the same level along the longitudinal axis of said riser.
• said second pads or preferably said rollers are arranged symmetrically around said riser with respect to its longitudinal axis and with at least three rollers, the axes of rotation of which are preferably still located substantially in the same plane.
• said first pads are mounted on an axis located substantially in the same horizontal plane as the axis of said rollers and said first pads and said rollers are arranged successively and symmetrically around said riser alternately.
• said first pads and said rollers are staggered, their respective axes of pivoting and rotation being located at different levels respectively along the longitudinal axis of said riser.
• said first skids are arranged on at least two different levels along said longitudinal axis of said riser, and said levels are arranged symmetrically with respect to a horizontal plane corresponding substantially to the median plane of the zone where said articulation means are located along the longitudinal axis.
• the axes of rotation of the rollers are arranged on at least two different planes perpendicular to said longitudinal axis of said riser, and said planes are arranged symmetrically with respect to a horizontal plane corresponding substantially to said median plane of the area along of the longitudinal axis of said riser where said articulation means are located.
• said first pads can be located on two different levels along the longitudinal axis of said riser, an upper level and a lower level and said rollers are located above said upper level and below said lower level.
• said first pads are located on two said different levels, an upper level and a lower level, and said rollers are located between said levels.
• the holding and guiding device according to the invention can be put in place on the floating support to hold and guide a riser in its production position, or it can be connected to means for transferring a riser from its position production towards the axis of a drilling derrick.
• said articulation means are preferably arranged at the level of the junction floor between said riser and said support, located between the bridge of the floating support and the water level. More preferably, the top of the cone with a half-angle at the top, less than 10 °, is situated substantially at the level of said junction floor.
• a holding and guiding device can also be put in place on said floating support to maintain and guide a riser in the operating position in a derrick installed on said floating support, more precisely at the axis of said derrick.
• a holding and guiding device On the axis of the derrick, one can set up a holding and guiding device according to the invention, at different levels along the axis longitudinal of the riser ZZ '. According to its positioning along the longitudinal axis, the dimensioning of the pads and rollers will be adapted according to the forces to be transmitted and the relative movements of the riser, tolerable with respect to the floating support.
• the same type of device may be used in the production position, or during the transfer of the riser from its production position to the axis of the derrick.
• the rollers or second pads are then dimensioned to withstand current forces corresponding to loads of up to 5 tonnes, and said first pads of extreme forces corresponding to loads of up to 50 tonnes.
• a device according to the invention at at least one of the two levels P ', and P' 2 , preferably respectively above and below said riser junction floor with respect to the floating support, the levels P and P ' 2 being located at different levels of the wall of the cavity of the floating support, but sufficiently spaced to maintain said riser substantially coaxial with the axis of the derrick, and not allow lateral movements of the riser such as the axis of the riser does not deviate more than 5 ° from the axis of the derrick; preferably no more than 2 °.
• the present invention therefore relates to a device comprising said articulation means comprising said first pads preferably cooperating with rollers, located on a first level P ', and a second level P' 2 along the wall of the central cavity of the floating support, respectively above and below the level P 0 of said junction floor between the riser and said floating support.
• the planes P ′ and P ′ 2 are advantageously spaced at most, in particular at least 5 , preferably at least 10 meters.
• the height of the wall of the cavity of the floating support represents approximately 30 meters, its draft being approximately 10 meters, and also insofar as the plane P ', is situated above the level of water and slightly below the level of the floating support bridge, it is possible that the lower plane P ′ 2 is located below the water level.
• said articulation means can be fixed inside a collar held in place around the riser by cables connected by a tensioning system to the wall of the cavity of said floating support. , at least one of said levels P ', and P' 2 .
• said articulation means comprising said first pads preferably cooperating with said rollers, are located at the end of a system of articulated arms comprising hydraulic cylinders.
• the articulated arm system can move between a closed position and an open position, so that in the closed position, said articulation means preferably comprise said rollers which are in contact with said riser, and in the open position, it allows the passage of a float adapted to said floating riser, said articulation means preferably said rollers remaining in contact with said float.
• each of the articulated arms of the same plane P '1 or P'2 can be adjusted in length, which makes it possible to create an offset of a known value between the axis of the riser and the axis of the derrick.
• the present invention also has for its object and a method for holding and guiding a floating riser with respect to a floating support allowing said riser to slide along its longitudinal axis ZZ 'and guiding its lateral displacements in a horizontal plane XX', YY 'perpendicular to said riser, using at least one holding and guiding device according to the invention.
• the present invention also has for object and a method for transferring a riser from its production position to its position within a drilling derrick on a floating support.
• moving said riser in said cavity of a floating support by moving said device for holding and guiding the riser relative to the floating support according to the invention, itself integral with said riser.
• the floating support comprises a central cavity comprising a plurality of compartments at the end of which said risers are in the production position, said compartments communicating with a central channel, at the end of which is located a drilling derrick, said compartments being arranged transversely to said central channel.
• said compartments and said central channel comprise a junction floor between said riser and said floating support on each bank defining a continuous channel of substantially constant width.
• said junction floor is integral with the wall of the cavity at an intermediate level between the bridge of the floating support and the water level.
• the floating support comprises means for transferring said risers between their production position at the end of the compartments and the position of the derrick, said transfer means making it possible to move a said riser along said junction floor by cooperating with said holding and guiding device ensuring the junction with said riser and said floating support at said junction floor.
• said transfer means are fixed and integral with said floating support.
• said transfer means comprise a set of winches and cables connecting said winches to said riser.
• said transfer means comprise a carriage movable along said compartments and said channel.
• said junction floor is equipped with guide rails which make it possible to move said transfer means or said riser, in particular if said transfer means are fixed, along said compartments and said central channel.
• Figure 1 is a top and plan view of the riser and the floating support with its central cavity, associated with a sectional view of the drilling derrick at a level corresponding to the level + 10m relative to said junction floor;
• Figure 2 is a plan view according to Figure 1, further comprising the means for transferring the holding and guiding device of riser according to the invention, from its production position to the axis of the derrick drilling ;
• Figure 3 is a schematic representation of the degrees of freedom of rotation authorized by the guide device according to the invention, and corresponding to the possible movement of the riser in the production position on its slot and throughout the transfer phase to the axis derrick;
• Figure 4 is a representation of the degrees of freedom of rotation and translation authorized by the guide device according to the invention, when the riser is in position at the axis of the derrick.
• the riser is guided on at least two distinct levels, at the level of the plane P and at the level of the plane P ′ 2 , said planes being sufficiently spaced;
• Figure 5 is a side view of a guide device according to the invention, comprising a multiplicity of rollers and pads installed alternately all around said riser, the pads and rollers being located on the same plane;
• Figure 6 is a variant of a device according to the invention, in side view a production riser and in section, the guide device is provided with an articulation of the laminated stop type and has a combination of rollers and pads installed on a tubular element substantially coaxial with the axis of said riser, the pads and rollers being located on different levels along the longitudinal axis ZZ ';
• Figure 7 is a top view of a device according to the invention resting on the junction floor on which is shown a channel allowing the assembly to be moved towards the axis of the derrick;
• Figure 8 is a side view of a guide device according to the invention associated with a riser in the operating position at the axis of the derrick, and mounted on the wall of the cavity or wellbay ;
• Figures 9 and 10 are top views detailing a collar which serves as a support for articulation means shown in the plane of the pads, which is kept in tension by three or four cables connected to a tensioning system;
• Figures 1 1 and 12 are side views of a riser in the operating position at the axis of the derrick, the devices according to the invention being mounted on articulated arm systems provided with hydraulic cylinder;
• FIG. 13 represents a side view of the riser provided with a holding and guiding device comprising articulation means 3 according to the invention, connected to transfer means 12 during transfer in the central channel 24 of the cavity of the floating support.
• FIG. 1 there is shown a top view and in plan the junction floor 4.
• the floating support comprises a cavity 23 comprising a plurality of compartments forming channels 23 ! and a central channel 24, said compartments 23, and said central channel 24 being of longitudinal shape and of substantially constant width and having continuity between said positions of the riser in the production position (slot) and the axis of the derrick.
• compartments 23 are arranged transversely relative to the central channel 24 which makes it possible to move a riser on the junction floor 4 between its production position at the end of said compartment 23, and the position at the axis of the derrick 14 to 1. end of said central channel.
• Ten production positions 11 have been shown, but only one is equipped with its riser 1 equipped with a guide device 3 secured to the junction floor 4.
• Figure 5 there is shown an embodiment of the device according to the invention, in which the pads 5 and the rollers 9 are located on the same plane, and the pads pivot around an articulation of axis 6 integral d 'a pad support 7, fixed, on the floating support 2.
• the production riser is equipped with a guide device 3 according to the invention allowing: a) the movements of the riser parallel to its longitudinal axis ZZ ', and b) the angular movements along axes XX' and YY 'situated in a horizontal plane, limited to the cone with a half-angle at the apex sommet, the half-angle of said cone being, according to the invention, less than 10 degrees ; c) very limited lateral displacements in the plane of the axes XX 'and YY'.
• the guide device shown in Figure 5 consists of a plurality of rollers and pads installed alternately all around said riser, the guide device comprises at least three rollers and three pads arranged in a regular manner or not around said riser.
• rollers 9, one of which is shown on the right-hand side of FIG. 5, are secured by means of roller supports 25, to a base 22, itself secured to the junction floor 4.
• the axis 10 of said caster is integral with a cylindrical part 26 whose internal bore is eccentric relative to the axis of said cylindrical part.
• This cylinder 26 is surrounded by a layer of elastomer 27 in the form of a ring, the assembly being held in position in the roller support 25 by means of a cap 28.
• Each of the rollers 9 is supported by a pair of supports of rollers 25 and ring 27, installed on the cylinder 26 on either side of said roller.
• the device thus described makes it possible to adjust, thanks to the eccentric assembly 10-26, the position of the caster relative to the outer wall of the riser; - (b) allows slight displacements of the eccentric assembly, when a load is applied by the riser on the roller, in the direction YY ', to the right.
• a similar result can be obtained by a spring system.
• the pads 5, one of which is shown on the left in FIG. 5, consist of an antifriction block 29, the opposite face of the riser having a curvature corresponding to that of said riser.
• the shoe is supported by an articulation of axis 6, of the spherical ball type or laminated stop, integral with a support for shoes 7.
• the laminated stops are composite materials of the sandwich type made up of layers of elastomers separated by metal reinforcements. and allow angular and longitudinal displacements which can be significant and the value of which can be adjusted by varying the thicknesses of elastomer, the number of layers and the arrangement of the metal reinforcements. Such devices are manufactured in particular by the Techlam France company.
• the shrinkage of the pads relative to the riser is low, for example of the order of a centimeter and the thickness of the elastomer ring 106 is calculated so as to allow a corresponding displacement of the axis of the caster.
• This thickness can be for example three centimeters.
• the forces encountered over the lifetime of a riser in the production position are of the order of 2 to 5 tonnes for 95% of the time, from 10 to 20 tonnes out of the 5% remaining with very exceptional load peaks, corresponding to 100-year conditions, which can reach and exceed 50 tonnes.
• the size and therefore the cost of the casters are optimized, the life of which may be significant without having to oversize them for extreme situations.
• the pads are sized for extreme cases and their maintenance can be carried out without difficulty during quiet periods when they are not active.
• FIG 6 there is shown a device according to the invention in which the pads 5 and the rollers 9 are located on different levels along the longitudinal axis ZZ 'of the riser, and the pads are fixed relative to a tubular element 7, itself able to pivot relative to the floating support.
• Figure 6 which is a variant of Figure 5 shows a side view of a production riser 1 equipped with a guide device 3 comprising a pad support consisting of a tube 7 coaxial with the longitudinal axis ZZ 'of the riser 1 and comprising, symmetrically with respect to the plane XX '/ YY', a plurality of rollers 9 provided with their eccentric assembly 10-26 and with the elastomer layer 27 in the form of a ring, in contact with said riser.
• the friction pads 5 are installed in a different plane, advantageously close to the plane XX '/ YY' and are not in contact with said riser.
• the entire guide is symmetrical with respect to the plane XX ′ / YY ′ and is secured to the junction floor 4 by an articulation 8 of the laminated abutment type comprising layers of elastomer 30 and metal reinforcements 31 made up of sheets formed according to portions of spheres of center O corresponding to the top of the cone limiting rotation.
• the laminated ball joint 8 then authorizes the rotations of the guide device 3 around the axes XX 'and YY' and keeps all of the rollers in contact with the riser 1.
• the rollers 9 erase and the pads then come into direct contact with the wall of the riser.
• the transmission of forces between riser and junction floor is then made substantially symmetrically with respect to the plane XX '/ YY' whatever the value of the angle ⁇ formed by the axis of the riser with the vertical, as indicated on the figure 5.
• Figure 7 is a top view relating to a guide device similar to that of Figure 6 showing the guide device 3 of the riser 1 in the position corresponding to the slot 1 1 and resting on the junction floor 4.
• Said floor junction 4 defines a channel 23, allowing the riser-guide device assembly to be moved towards the axis of the derrick 14.
• the guide device consists of:
• the pads 5 are here represented between two rollers 9 whereas in FIG. 6 they are shown in vertical alignment with said rollers.
• the tube 7 is connected to the support 22 by means of the laminated stop joint 8 of FIG. 6.
• FIGS. 8, 11 and 12 which represent a riser in the operating position at the axis of the derrick, associated with sections detailing the guiding devices according to the invention, located in planes P ', and P' 2 , the derrick is located above the deck 21 of the floating support and is integral with the latter.
• the various guide elements, as well as the junction floor 4 are integral with the wall 20 of the cavity (wellbay).
• the guide device 3 comprising articulation means according to the invention of the riser 1, in position P 0 corresponding to the junction floor 4, used for the transfer between the slot 1 1 and the axis 14 of the derrick 13 can: a ) or remain in place for the entire duration of the operations at the axis of the derrick, in which case the rollers will be in permanent motion during the displacement of the riser along the axis ZZ ', but no lateral force along the perpendicular axes XX' and YY '' will not be transmitted by this guidance to the structure beyond barge, because the forces are fully transmitted to said structure between the planes P ', and P' 2 : the guide device 3 can then be considered inactive, since it does not participate in lateral stabilization; b) either be dismantled for the duration of the operations at the axis of the derrick, then put back in place for the transfer back to the production slot position 1 1.
• the guide device according to the invention is associated with two guide collars fitted with skids and rollers.
• the collar In the plane P ', the collar is held by a system of hydraulic cylinders secured to the wall of the cavity or wellbay and connected to said collar, either directly or via live cables.
• the left jack is connected via a pulley, which is itself secured to the wall of the wellbay.
• the collar In plane P ′ 2 , the collar is held in place by a system of winches secured to the wall of the cavity or drilling bay and connected to said collar by means of live cables.
• the winch on the left is connected directly to said collar, the winch on the right is connected by means of a pulley itself secured to the wall of the cavity or wellbay.
• the guide device 3 comprising articulation means rests on arms 22, integral with the junction floor by means of vertical articulations 22 2 making it possible to fold down said arms 22, as also shown Figures 1 1 and 12, so as to free the passage, for example for the passage of a float.
• the collar 1 5 is held in position by at least three tensioned cables 1 6, two of which are dimensioned as explained below in the description of Figures 9 and 10.
• the cables 16 are connected to the collars 1 5 at the attachment ears and: a) in the plane P ', on the left of the drawing, to a hydraulic cylinder
• the collar 15 is held in tension by three or four cables 16 connected to a tensioning system not shown, characterized in that only two cables 16 have a length L, and L 2 adjusted so that the axis of the collar along the axis ZZ ', substantially coincides with the axis of the derrick.
• the other cables are then simply maintained in tension at a tension level higher than the anticipated extreme tension level, corresponding for example to the centennial conditions (100 Tons).
• the collar 15 consists of two half-shells connected on one side by a hinge 15, and on the other side by a locking system 15 2 allowing the assembly to be put in place around the riser and removed when operations are completed.
• Figure 1 0 is a four-strand version of Figure 9, wherein two of the strands are adjusted to a length corresponding to L1 and L2, the other two being simply held in tension.
• the device according to the invention makes it possible to add the coaxiality between the riser axis and the derrick axis by modifying, in the plane P ', and / or and in the plane P' 2 , the respective lengths Ll and L2 of the dimensioning cables.
• the device according to the invention also makes it possible to maintain the axis of the riser parallel to any given direction, substantially fixed relative to the axis of the derrick.
• the lower guide is shown in the open position, so as to allow the floats of a production riser to pass during assembly, when the various constituent elements are lowered.
• the guides remain in contact with the walls of the float so as to limit the movements of the entire suspended pipe.
• Figure 12 is a side view of a riser 1 being installed on the axis of the derrick.
• the guidance system of plane P ' 2 is identical to that of plane P',.
• the planes P ', and P' 2 are spaced eight to ten meters apart.
• the riser is being assembled, the assembly being lowered with a float 32.
• the lower guide is shown in the open position, so as to allow said float to pass, while remaining in contact with the walls of said float, so as to limit the movements of the entire suspended line.
• the guidance device linked to the plane P 0 is not yet installed around the riser 1, but will be installed as soon as the riser is ready to be transferred to its production slot.
• the articulated arms of the plane P ′ are provided with a mechanical or hydraulic device 34, making it possible to independently adjust the length of each of the arms, which allows by a coordinated variation of the length of each of the arms creates an offset from the top of the cone defined in FIGS. 5 and 6, of a known value, in a known direction from the plane P ',.
• a mechanical or hydraulic device 34 By advantageously equipping both planes P ′, and P ′, of articulated arms adjustable in length, it is possible to maintain the axis of the riser parallel to any direction substantially fixed relative to the axis of the derrick.
• the holding and guiding device 3 comprising articulation means, can be transferred towards the axis of the derrick using transfer means fixed relative to the floating support, constituted by winches 12, and 12 4 and cables 12 2 shown in FIG. 2.
• the junction floor 4 comprises means for transferring the riser and a guiding device according to the invention, consisting of winches 12, connected by cables 12 2 to the guiding device 3 moving by simple sliding on the junction floor 4 and being guided in the compartments 23, by rails 12 3 .
• winches 12 make it possible to move the riser-guide device 3 assembly between the slot position 1 1 and the axis of the central channel 24.
• the rails 12 3 facilitate the passage of the device 3 to the right of the adjoining compartments from the position of starting production, up to axis 14 of the derrick.
• the winches 12 4 are then connected to the support 22 of the guide device 3 by two cables 12 5 , and the cables 12 2 of the winches 12, are then disconnected.
• the riser-guide device 3 assembly is then transferred from the central position 24 to the axis 14 of the derrick.
• the riser can be moved by sliding the support 22 of the guide device 3 in the form of a washer as shown in FIG. 13.
• tubular elements 22, integral with the support 22 and arranged below the support 22 allow the guide to be guided.
• Friction pads 22 2 arranged below the support 22 and integral with it make it possible to slide the support 22 on the junction floor 8 under the action of the winches 12 4 and cables 12 5 (not shown) when are put into action.
• said guide device can just as easily be left in place. It is then opening, so as to be able to release the riser which is then supported by a second guide device ensuring the same function, with the difference that the transfer operation being of short duration and preferably being carried out in calm weather, said guiding device can be considerably simplified.

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• Physics & Mathematics (AREA)
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• Earth Drilling (AREA)
• Escalators And Moving Walkways (AREA)
• Filling Of Jars Or Cans And Processes For Cleaning And Sealing Jars (AREA)
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• Replacing, Conveying, And Pick-Finding For Filamentary Materials (AREA)
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• 1999
  • 1999-08-09 FR FR9910417A patent/FR2797464B1/fr not_active Expired - Fee Related
• 2000
  • 2000-08-03 AU AU68502/00A patent/AU6850200A/en not_active Abandoned
  • 2000-08-03 EP EP00956617A patent/EP1204807B1/de not_active Expired - Lifetime
  • 2000-08-03 BR BR0013258-6A patent/BR0013258A/pt not_active Application Discontinuation
  • 2000-08-03 KR KR1020027001777A patent/KR20020021682A/ko active IP Right Grant
  • 2000-08-03 DE DE60023308T patent/DE60023308D1/de not_active Expired - Lifetime
  • 2000-08-03 AT AT00956617T patent/ATE307266T1/de not_active IP Right Cessation
  • 2000-08-03 WO PCT/FR2000/002244 patent/WO2001011184A1/fr active IP Right Grant
  • 2000-08-03 US US10/049,012 patent/US6672804B1/en not_active Expired - Lifetime
• 2002
  • 2002-01-29 NO NO20020465A patent/NO20020465L/no not_active Application Discontinuation

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