IMPROVED EMERGENCY DISCONNECT FLUID TRANSFER JOINT ARM
The articulated fluid transfer arm with a rope unwinding device and braking mechanism addresses the high-torque requirement of emergency disconnections by limiting movement speed, reducing costs and ensuring safe repositioning.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- T EN LOADING SYST
- Filing Date
- 2024-12-19
- Publication Date
- 2026-06-26
AI Technical Summary
Conventional fluid transfer arms require high-torque actuators to manage emergency disconnections, which are costly, especially for electric actuators, due to the imbalance caused by fluid weight changes during disconnection.
An articulated fluid transfer arm with a rope unwinding device and a braking mechanism limits the speed of movement after emergency disconnection, allowing actuators to be sized for normal conditions, reducing the need for high torques.
The solution reduces costs by enabling actuators to operate efficiently under balanced conditions, avoiding overspeed and collision risks, and ensuring safe repositioning after emergency disconnections.
Smart Images
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Abstract
Description
Title of the invention: ARTICULATED FLUID TRANSFER ARM WITH IMPROVED EMERGENCY DISCONNECT Disclosure domain
[0001] This disclosure relates, in general, to articulated transfer arms (for example, for loading or unloading a ship) of fluid products and, more particularly, to general type loading arms comprising an articulated pipe mounted on a support and having at one end a coupling device adapted to be connected to a target pipe for the transfer of fluid from a storage tank to the target pipe or from this target pipe to the storage tank, a pipe balancing system and a two-part emergency disconnection device, one part of which remains attached to the coupling device connected to the target pipe and the other part to the remaining pipe detached from the target pipe, once the emergency disconnection has been activated. Prior art
[0002] A fluid product is defined as a liquid or gaseous product, such as a petroleum, gas, or chemical product. This type of product is intended to be transferred, for example, between a ship and a quay or jetty, or between two ships. In practice, the transfer arm is therefore fixed to the ground, a vehicle, or a boat.
[0003] For marine loading arms, this may involve: - of conventional marine loading arms as defined for example in patent applications FR2813872, FR2854156, FR2931451 or FR3064620; - marine loading arms without a base allow reaching low connection points as defined for example in patent application FR2964093; - bunkering or hybrid arms (one rigid part and one flexible part) as defined for example in patent application FR3003855.
[0004] These transfer arms can operate with electric actuators.
[0005] The use of such actuators has already been proposed in the aforementioned patent applications FR2931451 or FR3064620.
[0006] These must be dimensioned so as to be able to maneuver the arm after an emergency disconnection, where it is generally in a situation of imbalance (under-equilibrium or over-equilibrium depending on whether the piping is loaded with fluid or not and depending on the "weight dropped", i.e. the weight of the part separated from the arm after the emergency disconnection.
[0007] This is a situation that rarely occurs but requires high torque. However, the cost of actuators, especially if they are electric, is directly related to the value of the torque supplied.
[0008] The present disclosure aims to propose a solution that overcomes this drawback and also leads to other advantages. Statement of Disclosure
[0009] To this end, the present disclosure relates to an articulated fluid transfer arm comprising an articulated pipe mounted on a support, having at least one degree of rotational freedom relative to the support and comprising at one of its ends a coupling device adapted to be connected to a target pipe for the transfer of fluid from a storage tank to the target pipe or from this target pipe to the storage tank and an emergency disconnection device for the piping from the target pipe, configured to be able to be separated into a first and a second part during an emergency disconnection procedure, the first part remaining attached to the coupling device connected to the target pipe and the second part remaining attached to the rest of the piping detached from the coupling device;one or more electric actuators to control each movement of the piping per degree of freedom via an actuating shaft; and a piping balancing system, characterized in that the articulated fluid transfer arm comprises a rope connected at one end to one of the first and second parts and wound from its other end onto a device for winding and unwinding the rope and mounted on the other of the first and second parts, the rope unwinding device being functionally connected to a braking mechanism configured to act on the unwinding device so as to limit the speed of movement of the piping after an emergency disconnection procedure.
[0010] Thus, the proposed solution allows the rope to unwind at a limited speed due to the function of the braking mechanism.
[0011] The electric actuators can then be sized solely to maneuver the transfer arm under normal / balanced conditions. Therefore, only low torques are required, resulting in a significant cost reduction compared to conventional solutions.
[0012] The rope unwinding device can be configured to be operated in rotation by a motor or a manual actuator to ensure the rewinding of the rope.
[0013] In one embodiment, for reconnecting the two parts of the emergency disconnection device, the winding and unwinding device is energized to bring the two parts together by winding the rope in order to reassemble them, if necessary after attaching the rope to the winding and unwinding device.
[0014] The articulated fluid transfer arm according to this disclosure may also include one or more of the following features, taken individually or in any technically feasible combination(s): - the unwinding device includes a winch mounted on the first part and the braking mechanism includes a centrifugal brake configured to act on the axis of rotation of a winch cylinder around which the rope is wound; - the winch includes an electric, hydraulic or pneumatic motor whose shaft is connected to the axis of the cylinder via a speed reducer coupled in rotation to the shaft of the winch motor; - the speed reducer is a reversible speed reducer and the centrifugal brake is interposed between the electric motor and the reversible speed reducer or coupled in rotation to the shaft of the electric motor on the side of the shaft opposite to that of coupling in rotation to the speed reducer; - the unwinding device includes a motorized winch with speed limiter, hydraulic or electric, mounted on the second part and whose motor is equipped with the braking mechanism; - (i) the winch motor is a hydraulic motor and the braking means of the latter include at least one hydraulic braking valve connected to the hydraulic motor which is configured to operate as a pump in its brake dial, or (ii) the winch motor is an electric motor and the braking means thereof include an electrical resistor connected to the motor which is configured to operate as a generator returning the energy generated by braking into the resistor; - rope is a cord or a cable; - the rope is attached in a removable manner to the unwinding device; - the emergency disconnection device is a system comprising two valves joined together by means of a collar with an opening controlled by at least one electrical, hydraulic, pneumatic, or mechanical actuator; - the centrifugal brake is housed in an explosion-proof casing, or - the inside of the brake is under purging or pressurized with dry air or nitrogen, or - the linings of the centrifugal brake are made of a material that does not generate sparks; - the centrifugal brake is sized to absorb the braking energy without the temperature of its outer surface exceeding a temperature maximum predefined permissible temperature, or without the temperature of its outer surface and the temperature of its inner surface exceeding the maximum predefined permissible temperature; - the arm comprises an inner tube and an outer tube articulated between them, the inner tube pivoting on the support and the outer tube carrying the emergency disconnection device and the coupling device; - the actuator(s) comprise an electric motor with a shaft and a speed reducer, the actuating shaft being driven in rotation by the motor shaft by means of the speed reducer, which is reversible, so as to allow the actuating shaft to rotate when an actuating torque is directly applied to it; - the electric motor of each actuator is a vector control motor with position feedback by encoder, configured to hold the electric actuator containing it in position; - said piping balancing system is a counterweight balancing system; - the arm also includes a reconnecting rope connected at one end to the section of piping intended to be detached from the coupling device, to bring the first and second parts of the emergency connection device back into a connection position with each other, after an emergency disconnection procedure.
[0015] According to this disclosure, an emergency disconnection method for an articulated fluid transfer arm as defined above is also provided, according to which, during the emergency disconnection sequence, the movement of the fluid transfer arm to a parking position is partially or totally controlled by the electric actuators with the aid of the braking mechanism.
[0016] This disclosure further proposes a method for reconnecting an emergency disconnection device of a fluid transfer arm as defined above, wherein (i) the rope unwinding device is actuated in rotation or (ii) a reconnection rope connected by one of its ends to the portion of piping intended to be detached from the coupling device is subjected by its other end to a pull by means of a pulling device external to the fluid transfer arm, to bring the first and second parts of the emergency disconnection device into a position of connection of one to the other. Description of the figures
[0017] This disclosure, and its various advantages, will be more easily understood in light of the following description of an illustrative and non-limiting embodiment thereof, and the accompanying drawings, among which:
[0018] Fig. 1 is a schematic view of an articulated fluid transfer arm according to one disclosure embodiment, arranged on a jetty and connected to a ship;
[0019] Fig. 2 is a schematic view of the articulated fluid transfer arm of Fig. 1 during operation following an emergency disconnection procedure;
[0020] Fig. 3 is a side view with partial section illustrating the centrifugal brake implemented between the speed reducer and the winch motor of Fig. 2;
[0021] The [Fig.4] is a side view with partial section of the centrifugal brake of the [Fig.3];
[0022] Figure 5 is a cross-sectional view of the part of the centrifugal brake marked A on the [Fig.4];
[0023] Fig. 6 is a schematic view of the articulated fluid transfer arm in the parking position following an emergency disconnection procedure;
[0024] Fig. 7 is a schematic view of the articulated fluid transfer arm during maneuvering under unbalanced slump conditions following an emergency disconnection procedure;
[0025] The [Fig.8] is a schematic view of the articulated fluid transfer arm in the parking position after detachment of the cable from its winch;
[0026] Fig. 9 is a schematic view of the articulated fluid transfer arm during a reconnection procedure;
[0027] Figures [Fig. 10] and [Fig. 11] are schematic views of an articulated transfer arm fluid according to an embodiment with a winch on the upper part of the emergency disconnection device.
[0028] Detailed description of a disclosure embodiment
[0029] With reference to [Fig. 1], an example of an articulated arm for transferring fluid 10 from a storage position (such as a tank, not shown in the figures) to a target pipe 33 located on a ship 3 and from this target pipe 33 to the storage position is described, the articulated fluid transfer arm 10 comprising a fluid transfer line or piping 20 having at one of its ends a coupler, here of the "QCDC" type 31 for "Quick Connect Disconnect Coupling", adapted to be connected to the target pipe 33 for the transfer of the fluid, and electric actuators 11, 12, 13 for controlling the movement of the transfer line in space, each by means of an actuating shaft.
[0030] This is therefore a marine loading arm, used for example for the transfer of liquefied natural gas.
[0031] The articulated fluid transfer arm 10 also includes a support for the piping 20 and the means for operating it, which is in the form of a base 21. This base 21 is fixed on a jetty 4. The base 21 could also have been fixed on a vehicle or a boat.
[0032] The piping 20 is articulated and more specifically comprises an inner tube 22, an outer tube 23 and a terminal assembly with three rotating joints 32 ending with the coupler 31.
[0033] The inner tube 22 is connected at one end to a tube housed in the base 21 and at a second end to a first end of the outer tube 23 via a swivel joint. The outer tube 23 is connected at a second end to a first end of the terminal assembly 32 via three swivel joints, through the first of the three swivel joints.
[0034] The first two swivel joints precede an emergency release system 14 (in English “ERS” for “Emergency Release System”) allowing the piping 20 to be disconnected from the target pipe 33 and which is here part of the terminal assembly 32, while the third joint connects this device to the coupler 31. In other embodiments, the emergency release system 14 can be arranged further upstream on the piping.
[0035] The coupler 31 is thus articulated at the end of the piping with at least three degrees of rotational freedom, thanks to the rotating joints implemented.
[0036] The emergency disconnection system 14 of this embodiment comprises, in a manner known per se, two valves joined by means of a collar, the opening of which is controlled by at least one electric actuator 14', said at least one electric actuator 14' also controlling the closing of the valves. In practice, this control can, for example, be achieved by the translational movement of a rod, as described, for example, in patent application WO2007 / 017559.
[0037] In other words, this is an emergency disconnection device 14 configured to be able to be separated into a first and a second part during an emergency disconnection procedure, the first part or lower valve remaining attached to the coupler 31 connected to the target pipe 33 and the second part or upper valve remaining attached to the rest of the piping detached from the coupler 31.
[0038] Alternatively, the emergency disconnection system may be devoid of valves.
[0039] The articulated fluid transfer arm 10 is also equipped with a piping balancing system, which is here a counterweight balancing system, comprising here two counterweights 16a, 16b, one 16a of which is disposed at one end of the inner tube 22 and the second 16b is disposed on a pantograph 15. Alternatively, balancing can be achieved by means of springs or any other balancing solution.
[0040] The electric control actuators 11, 12, 13 allow the movement of the joints of the fluid transfer arm 10 to be controlled. In practice, not all degrees of freedom of the arm are necessarily actuated. Typically, an arm has six degrees of freedom and three are actuated.
[0041] The rotation around a vertical axis of the compass formed by the tubes 22 and 23 is controlled by the rotation of the electric operating actuator 12.
[0042] The actuation of the pantograph 15 is controlled by the rotation of the second electric maneuvering actuator 13 and allows the deployment of the outer tube 23.
[0043] Furthermore, the rotation of the inner tube 22 around a horizontal axis, parallel to the horizontal axis of rotation of the outer tube 23, is ensured here by means of the electric operating actuator 11.
[0044] The complete mechanical structure is here arranged in an area with an explosive atmosphere, as described for example in application FR3064620. In this area there is also a junction box 41 establishing the link between on the one hand a control cabinet 42 and on the other hand the electrical actuators 11, 12, 13, 14.
[0045] Each of the electric actuators 11-13 is, in this embodiment, an actuator comprising an electric motor, a speed reducer equipped with an adapter for connection to the electric motor, the actuation gear of the corresponding tube(s) of the articulated fluid transfer arm 10 being driven in rotation by the motor shaft by means of the speed reducer, which is here reversible, so as to allow the actuation shaft to rotate when an actuation torque is directly applied to it.
[0046] When a single electric actuator does not have enough power to drive the actuation gear into rotation, two electric actuators can be mounted.
[0047] The electric motor used here is an asynchronous motor.
[0048] It can also be a brushless motor.
[0049] The speed reducer here is an assembly of two straight or helical gear reducers.
[0050] This reducer could, for example, also be an epicyclic gear reducer.
[0051] Such a speed reducer can operate reversibly because little friction is generated and the efficiency of the speed reducer is high, on the order of more than 90%.
[0052] Furthermore, each electric motor here is vector-controlled with position feedback via an encoder. This motor control method allows the motor torque to be controlled at zero speed and thus maintains the position of the associated section of piping.
[0053] As can be seen more clearly in particular in [Fig. 2], where the articulated fluid transfer arm 10 is schematically represented after an emergency disconnection, this arm according to this embodiment of the present disclosure, further includes a rope 51 wound from one of its ends on a device 50 allowing the winding and unwinding of the rope 51 and mounted on a first part 14a of the emergency disconnection device 14. The other end of the rope 51 is connected to the second part 14b of the emergency disconnection device 14.
[0054] This cord 51 is removably attached to the winding and unwinding device 50. In this case, it is a cable. Alternatively, a rope could be used.
[0055] The rope winding and unwinding device 50 is, in general, configured to be driven in rotation by a motor and is functionally connected to a braking mechanism configured to act on the winding and unwinding device 50 in such a way as to limit the speed of movement of the piping after an emergency disconnection procedure.
[0056] The rope winding and unwinding device 50 more specifically comprises here a winch 52 equipped, for winding the cable 51 during a reconnection procedure of the two parts 14a, 14b of the emergency disconnection device, with an electric, pneumatic or hydraulic motor 53, the shaft of which is connected to the axis of rotation of the winch cylinder 52 around which the rope 51 is wound, by means of a speed reducer 54 coupled in rotation to the shaft of the electric motor.
[0057] The braking mechanism includes a centrifugal brake 60 configured to act on the axis of rotation of the winch cylinder 52.
[0058] In the present embodiment (see [Fig. 3]), the speed reducer 54 is a reversible speed reducer, as is the case for actuators 11-13, and the centrifugal brake 60 is interposed between the winch motor 53 of the winch 52 and the reversible speed reducer associated with that motor. Alternatively, the centrifugal brake 60 can be rotationally coupled to the shaft of the electric motor, on the side of that shaft opposite to the side of rotational coupling to the speed reducer.
[0059] The centrifugal brake 60 is more particularly shown in figures 4 and 5.
[0060] The centrifugal brake 60 comprises a rotor 61 formed to rotate about an axis intended to be confused with the shaft of the electric motor and the speed reducer. This rotor 61 is extended on one side by a shaft 62 configured to facilitate connection with the speed reducer. Similarly, the rotor 61 includes a bore on the other side, configured to connect with the output shaft of the electric motor.
[0061] The rotor 61 is provided opposite a stator 63. Friction means 64 are positioned opposite weights 65 provided on the outer circumference of the rotor 61 and are integral with these weights 65. The weights 65 are held on the rotor by springs 66.
[0062] In this way, at a given centrifugal force, corresponding to a given rotational speed, the weights 65 and the friction means 64 move radially away from the rotor 61 to come into contact with the stator 63 and exert on the stator 63 a contact force enabling the generation of a braking torque.
[0063] The weights 65 are actually pressed against the rotor by the springs 66. Thus, when the centrifugal force is greater than the pressing force exerted by the springs 66 on the weights 65, the weights 65 then move away radially from the rotor 61.
[0064] The centrifugal brake further includes guides 67 for the weights 65. These guides 67 allow the weights 65 to be guided radially to ensure that they return to the correct angular position on the rotor 61 when the centrifugal force decreases and the weights 65 return to press against the rotor 61.
[0065] It is this braking force which makes it possible to limit the speed of movement of the piping when the latter is in a situation of imbalance, which is generated in this embodiment following an emergency disconnection.
[0066] More specifically, the weights 65 and the friction means 64 exert this braking force on the stator from a predefined engagement speed. This engagement speed can notably be calculated based on the characteristics of the fluid transfer arm 10 and the characteristics of the entity carrying the target tube 33 (taking into account, for example, potential movements and external conditions), it being understood that it corresponds to the speed at which the centrifugal effect will be sufficient for the weights 65 and the friction means 64 to initiate a braking action by their contact with the stator 63.
[0067] It should be noted that, for safety reasons, the friction means 64 of the centrifugal brake in this embodiment are made of a material that does not generate sparks and the assembly is dimensioned so that the temperatures of the internal and external walls remain below a maximum permissible temperature, here of 135°C.
[0068] Thus, and as will be seen in more detail below, the centrifugal brake 60 does not block the movement of the elements of the articulated fluid transfer arm 10, but slows it down so that the articulated arm can regain equilibrium. In other words, this centrifugal brake cancels the acceleration to reach a constant speed and maintain that speed.
[0069] The centrifugal brake is therefore a passive element which has the advantage of not needing to be controlled to have optimal operation.
[0070] According to some embodiments, it should be noted that the centrifugal brake can be housed in an explosion-proof casing. The interior of the brake can also be purged or pressurized with dry air or nitrogen. In these cases, the The sizing is such that the temperature of the outer wall of the stator remains below the maximum permissible temperature.
[0071] We now detail the operating conditions of this centrifugal brake 60 as a function of the situation of the articulated fluid transfer arm 10.
[0072] As long as no emergency disconnection procedure takes place, the cable 51 is not unwound and, consequently, the centrifugal brake 60 does not come into action. This is the case in the parking position (articulated fluid transfer arm 10 not deployed), the balanced maneuvering position of the articulated fluid transfer arm 10, or the position connected to the target tubing 33. In this last position, the actuators 11-13 are disengaged so as to make the movements of the articulated fluid transfer arm 10 free to allow the coupler 31 to follow the movements of the target tubing 33 (the "freewheeling" mode).
[0073] Following an emergency disconnection procedure, as shown in [Fig.2], the articulated fluid transfer arm finds itself in a situation of imbalance, the arm being underbalanced or overbalanced depending on the quantity of product remaining in the piping, with in particular risks of collisions with the ship.
[0074] However, thanks to the speed limiting provisions described above, the cable 51 connecting the two parts 14a, 14b of the emergency disconnection device 14 to each other unwinds at a limited speed due to the action of the centrifugal brake 60 and, therefore, limits the speed of movement of the part of the piping without the coupler 31 after the emergency disconnection.
[0075] If the arm 10 is over-balanced after the emergency disconnection procedure (no or very little product in the piping), the return of the arm to its parking position illustrated in [Fig.6] thus takes place without risk of overspeed which could prove damaging to the arm when it arrives in the parking position.
[0076] Alternatively, the emergency disconnection sequence may also include sending an instruction to one or more of the actuators 11-13 to take control of the fluid transfer arm 10 and move it to its parking position. In other words, the raising of the arm can be partially or fully controlled by the electric actuators 11-13 with the aid of the centrifugal brake 60.
[0077] If the arm is underbalanced (low "dropped weight" compared to the weight of product in the full or partially filled piping), the imbalance can cause the arm to sag (downward movement) and pose a risk of collision with the vessel 3 because the natural trajectory of the upper part 14b of the emergency disconnect device 14 is generally not completely vertical (see [Fig. 7]). In this situation, the limited-speed unwinding of the cable 51 slows the downward movement, and the actuators 11-13 are used to control the upward trajectory of the fluid transfer arm to its parking position. In practice, good control of the emergency retraction trajectory can be achieved using only the actuator 11 of the inner tube 22.
[0078] Regardless of the arm's imbalance, no overspeed occurs thanks to the speed-limiting provisions described above. Therefore, the actuators 11-13 are sized to control the arm under normal / balanced conditions and are sufficient to also return the arm to its parking position after an emergency disconnection procedure. Only low torques are required, resulting in a significant cost reduction compared to a solution without these provisions. These torques are even lower when the weight of the components released during the emergency disconnection procedure is greater.
[0079] It will also be observed (see [Fig.6]) that in the parking position, the outer tube 23 opens until it reaches a mechanical support limiting its angle at the top to a maximum, which is generally 150°.
[0080] In this position, the inner tube 22 is mechanically locked when the arm reaches its parking (vertical) position.
[0081] Alternatively, another parking position of the outer tube 23 can be chosen, such as for example a normal parking position with an angle at the top between 10° and 15°, if the torque of the actuator of the outer tube is sufficient.
[0082] As can be seen in [Fig.8], if the ship 3 continues to drift, the cable 51 automatically detaches from the winch cylinder 52.
[0083] For reconnecting the emergency disconnect device 14 when the vessel 3 returns to a safe working area, the cable 51 is attached to the winch cylinder 52 and the latter is energized to pull the upper part or valve 14b over the lower part or valve 14a and thus be able to raise the collar of the emergency disconnect device 14 (see [Fig.9]).
[0084] In this case, the speed reducer increases the torque supplied to the winch cylinder 52 when the cable 51 is wound.
[0085] An alternative may be to use an external means to pull back part 14b, such as for example a manual winch with a passing cable or a Tirfort winch.
[0086] According to other embodiments (see figures 10 and 11), the unwinding device 150 may include a motorized winch 152 with a speed limiter, hydraulic or electric, mounted this time on the second part 114b of the emergency disconnection device and whose motor is equipped with the braking mechanism.
[0087] Indeed, when the unwinding device is mounted on the part of the piping remaining attached to the articulated fluid transfer arm 110 (outer tube 123), it is possible to have a hydraulic and / or electrical connection 170 with the jetty and it is therefore not necessary to implement an autonomous braking mechanism.
[0088] According to a first aspect, the winch motor 152 is a hydraulic motor and its braking mechanism includes at least one hydraulic braking valve connected to the hydraulic motor which is configured to operate as a pump in its brake dial.
[0089] According to another aspect, the winch motor 152 is an electric motor and its braking mechanism includes an electrical resistance connected to the variator which returns the energy generated by braking to the resistance.
[0090] Thus, the alternative to braking with a centrifugal brake is braking with a hydraulic or electric motor then used in the brake dial.
[0091] The motor actually operates in the motor dial when the load is driven (as is the case for example when hoisting a load with a winch).
[0092] It operates in the brake dial when the load is driving (for example, lowering a load).
[0093] In the brake dial, the hydraulic motor operates as a pump. The energy generated by braking is dissipated in the hydraulic brake valve by heating the oil.
[0094] In the brake dial, the electric motor operates as a generator and the energy generated by braking is returned to a resistor.
[0095] In the arrangement shown in figures 10 and 11 with the winch 152 fixed on the part 114b, the motor can be fixed to the winch only when needed to reconnect the arm 110 after an emergency disconnection.
[0096] An alternative may also be to move the arm towards the target pipe of the ship using external equipment, such as a manual winch with a through cable (tirfort). In this case, the motor is not required.
[0097] This alternative is shown in Figures 10 and 11 with a reconnection cable 180 added to the cable 151 of the unwinding device 150. In practice, the latter detaches from the winch 152 at the end of the emergency disconnection procedure, but remains attached to the part 114b integral with the target tube 133, while the reconnection cable 180 is attached to the outer tube 123 of the arm 110 by one of its ends. Its opposite end is free and, once this cable 180 has been unwound at the end of the emergency disconnection procedure, it will be used for reconnection via the manual winch with a through-cable.
[0098] More generally, the following points should also be noted regarding the embodiments described above and possible variations thereof. The fluid transfer system described with reference to the drawings is an articulated arm whose inner and outer tubes are self-supporting. Alternatively, these can be supported by a support structure. More generally, it can be a type of a fluid transfer system of the kind described in the patent applications mentioned above.
[0099] In the embodiments described above, the reversible gearbox meshes with a gear that is either rotationally coupled to the piping or coupled to a drive system for the piping. More precisely, it is attached to a swivel joint of a set of elbows and swivel joints connecting, typically, two sections of the piping, or to the pantograph system used to rotate a section of the piping. When a support structure is used, the gear can, of course, be coupled to this support structure.
[0100] Each motor and its gearbox can also be in the form of a geared motor. Furthermore, each electric motor can be synchronous or asynchronous.
[0101] The reversible reducer can also be coupled to the piping or to a support structure thereof by means of a rack bar in direct or indirect contact with the piping. This forms the equivalent of an electric actuator with the assembly consisting of the electric motor, the speed reducer, and the rack bar drive pinion(s).
[0102] The centrifugal brake can be rotationally coupled to the axis of rotation of the cylinder on the side of this axis opposite to that which is rotationally coupled to the electric motor.
[0103] This winding and unwinding device motor can also be in the form of a pneumatic gun acting for example on the axis of the cylinder on which the cable is wound.
[0104] This cylinder can be replaced by a grinder.
[0105] More generally also, the structure of the centrifugal brake is not limited to that described above, but could be any equivalent structure available commercially.
[0106] Braking means, other than those described above, may also be envisaged, such as for example an electromagnetic brake with regulation of braking torque to control speed.
[0107] Instead of the three rotational degrees of freedom obtained with the arm described above (or even 6 by adding roll, pitch and yaw), an arm according to the invention can also have fewer rotational degrees of freedom than three, such as for example two, or even only one, by implementing a piping comprising a rigid pipe section and a flexible pipe section, of which the rigid pipe section has one or two rotational degrees of freedom.
Claims
Demands
1. Articulated fluid transfer arm (10; 110) comprising an articulated pipe (20) mounted on a support (21), having at least one degree of rotational freedom relative to the support and comprising at one end a coupling device (21) adapted to be connected to a target pipe (33; 133) for transferring fluid from a storage tank to the target pipe (33; 133) or from this target pipe (33; 133) to the storage tank and an emergency disconnection device (14) for the pipe (20) of the target pipe (33; 133), configured to be able to be separated into a first and a second part (14a, 14b; 114a, 114b) during an emergency disconnection procedure, the first part (14a; 114a) remaining attached to the coupling device (31) connected to the target tubing (33; 133) and the second part (14b; 114b) remaining attached to the rest of the piping (20) detached from the coupling device (31);one or more electric actuators (11-13) to control each movement of the piping (20) per degree of freedom via an actuating shaft; and a balancing system (16a, 16b) for the piping (20), characterized in that the articulated fluid transfer arm comprises a rope (51; 151) connected at one end to one of the first and second parts (14a, 14b; 114a, 114b) and wound from its other end onto a device (50; 150) allowing the winding and unwinding of the rope (51; 151) and mounted on the other of the first and second parts, the rope unwinding device (50; 150) being functionally connected to a braking mechanism (60) configured to act on the unwinding device so as to limit the speed of movement of the piping after an emergency disconnection procedure.
2. Articulated fluid transfer arm according to claim 1, wherein the rope unwinding device (50; 150) is configured to be rotationally actuated by a motor (53) or a manual actuator to ensure the rewinding of the rope.
3. Articulated fluid transfer arm according to claim 1 or 2, wherein the unwinding device (50) comprises a winch (52) mounted on the first part and the braking mechanism (60) includes a centrifugal brake configured to act on the axis of rotation of a winch cylinder (52) around which the rope is wound.
4. Articulated fluid transfer arm according to claim 3, wherein the winch (52; 152) comprises a hydraulic or pneumatic electric motor whose shaft is connected to the axis of the cylinder via a speed reducer rotationally coupled to the shaft of the winch motor.
5. Articulated fluid transfer arm according to claim 4, wherein the speed reducer is a reversible speed reducer and the centrifugal brake (60) is interposed between the electric motor and the reversible speed reducer or rotationally coupled to the shaft of the electric motor on the side of the shaft opposite to that of rotationally coupled to the speed reducer.
6. Articulated fluid transfer arm according to claim 1, wherein the unwinding device (50; 150) comprises a motorized winch with speed limiter, hydraulic or electric, mounted on the second part and whose motor is equipped with the braking mechanism.
7. Articulated fluid transfer arm according to claim 6, wherein (i) the winch motor is a hydraulic motor and the braking means thereof comprise at least one hydraulic braking valve connected to the hydraulic motor which is configured to operate as a pump in its brake dial, or (ii) the winch motor is an electric motor (53) and the braking means thereof comprise an electrical resistor connected to the motor which is configured to operate as a generator returning the energy generated by braking into the resistor.
8. Articulated fluid transfer arm according to any one of claims 1 to 7, wherein the rope (51; 151) is a rope or cable.
9. Articulated fluid transfer arm according to any one of claims 1 to 8, wherein the rope is removably fixed to the unwinding device (50; 150).
10. Articulated fluid transfer arm according to any one of claims 1 to 9, wherein the emergency disconnection device (14) is a system comprising two valves joined together by means of a collar with opening controlled by at least one electrical (14'), hydraulic, pneumatic, or mechanical actuator.
11. Articulated fluid transfer arm according to any one of claims 3 to 5, wherein: - the centrifugal brake (60) is housed in an explosion-proof enclosure; or - the interior of the brake (60) is under purging or pressurized with dry air or nitrogen; or - the linings of the centrifugal brake (60) are made of a non-sparking material.
12. Articulated fluid transfer arm according to any one of claims 3 to 5, wherein the centrifugal brake (60) is dimensioned to absorb the braking energy without the temperature of its outer surface exceeding a maximum predefined permissible temperature, or without the temperature of its outer surface and the temperature of its inner surface exceeding the maximum predefined permissible temperature.
13. Articulated fluid transfer arm according to any one of claims 1 to 12, wherein the arm comprises an inner tube (22) and an outer tube (23) articulated with each other, the inner tube pivoting on the support and the outer tube carrying the emergency disconnection device and the coupling device.
14. Articulated fluid transfer arm according to any one of claims 1 to 13, wherein the actuator or each of the actuators (11-13) comprises an electric motor with a shaft and a speed reducer, the actuating shaft being driven in rotation by the motor shaft by means of the speed reducer, which is reversible, so as to allow the actuating shaft to rotate when an actuating torque is directly applied to it.
15. Articulated fluid transfer arm according to any one of claims 1 to 14, wherein the electric motor of each actuator (11-13) is a vector-controlled motor with position feedback by encoder, configured to hold in position the electric actuator comprising it.
16. Articulated fluid transfer arm according to any one of claims 1 to 15, characterized in that said balancing system (16a, 16b) of the piping is a counterweight balancing system.
17. Articulated fluid transfer arm according to any one of claims 1 to 16, further comprising a reconnecting rope (180) connected at one end to the portion of piping intended to be detached from the coupling device, to return the first and second parts of the emergency connection device to a connection position of one to the other, after an emergency disconnection procedure.
18. Method for emergency disconnection of an articulated fluid transfer arm according to any one of claims 1 to 17, wherein, during the emergency disconnection sequence, the movement of the fluid transfer arm (10; 110) to a parking position is partially or fully controlled by the electric actuators with the aid of the braking mechanism.
19. Method of reconnecting an emergency disconnection device of a fluid transfer arm according to any one of claims 1 to 17, wherein (i) the unwinding device (50; 150) of the rope is actuated in rotation or (ii) a reconnection rope (180) connected by one of its ends to the portion of piping intended to be detached from the coupling device is subjected by its other end to a pull by means of a pulling device external to the fluid transfer arm, to bring the first and second parts of the emergency disconnection device (14) into a position of connection of one to the other.