Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B21/00—Tying-up; Shifting, towing, or pushing equipment; Anchoring
  • B63B21/56—Towing or pushing equipment
  • B63B21/66—Equipment specially adapted for towing underwater objects or vessels, e.g. fairings for tow-cables
  • B63B21/663—Fairings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
  • B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
  • B66D1/28—Other constructional details
  • B66D1/40—Control devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
  • B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
  • B66D1/28—Other constructional details
  • B66D1/40—Control devices
  • B66D1/48—Control devices automatic

Definitions

• the present invention relates to ducted tractive cables used on a ship to tow a submersible body dropped at sea and the handling of these cables. It relates more particularly to tractors trenches careened by hulls hinged together.
• the context of the invention is that of a naval vessel or vessel intended to tow a submersible object such as a variable immersion sonar integrated in a towed body.
• the submersible body in the nonoperational phase the submersible body is stored on board the ship and the cable is wrapped around the drum of a winch for winding and unrolling the cable, that is to say to deploy and to retrieve the cable.
• the submersible body in the operational phase, the submersible body is immersed behind the ship and towed by the latter by means of the cable whose end connected to the submersible body is submerged.
• the cable is deployed, it is towed by the ship and has a submerged end.
• the cable is wound by the winch through a guide device for guiding the cable.
• the guiding device makes it possible to limit the lateral movement of the cable. It conventionally includes a pulley.
• FIG. 1A shows a portion of the cable 1 extending along an axis x.
• This cable is streamlined, it is covered with hulls having shapes designed to reduce hydrodynamic drag.
• the hulls form a fairing also called fairing column.
• the hulls are rigid. In other words, they do not deform under the effect of the hydrodynamic flow.
• the cable 1 is conventionally streamlined by means of a fairing or fairing column 3 comprising a series of hulls 2, or hulls.
• Each hull 2 comprises an elongate member having a hydrodynamic profile.
• the hydrodynamic profile is the shape of a section of the fairing section in a plane perpendicular to the x axis.
• the hydrodynamic profile of the hulls is, for example, as shown in FIG. 1B, in the form of a wing having a thick inner edge (or leading edge BA) housing a tubular channel in which the cable 1 passes and a thin outer edge (or trailing edge BF) allowing a less turbulent flow of water around the cable.
• the hydrodynamic profile has, for example, a droplet shape or is a NACA profile, that is to say a profile defined by NACA which is an acronym for the English expression "National Advisory Committee for Aeronautics". All hulls totally or partially cover the cable. The hulls are immobilized in translation relative to the cable along the x axis.
• the hulls are rotatably mounted around the cable, that is to say around the x-axis.
• Each hull is, however, linked to its two neighbors so as to be pivotable with respect thereto about an axis parallel to the x-axis of a small maximum angle of the order of a few degrees.
• these phases are: the following orientation the flow of water, the orientation to pass the pulleys, the slicing, the guiding device and the storage on the reel.
• the rotation of a shell causes a rotation of the hulls nearby and gradually that of all the hulls.
• any change in orientation of one of the hulls affects gradually all hulls careening the cable.
• the cable is deployed at sea hulls are naturally oriented in the direction of the current generated by the movement of the building.
• all the hulls adopt, as the cable rises, the same orientation relative to the drum, an orientation that makes it possible to wind the cable while maintaining the hulls parallel to each other. to others in turn.
• the object of the present invention is to provide a cable handling method that limits the risk of damage to the fairing of a towed cable to limit the risk of immobilization of the sonar system.
• the applicant firstly, in the context of the present invention, identified and studied the cause of this problem of crushing the hulls by observation of the ducted cable in operational situation and by modeling ducted cable in operational situation and different forces acting on it, including hydrodynamic and aerodynamic flows and gravity.
• the fairway cable is towed by the vessel and has a submerged end.
• the tow point is a point on a pulley that is at a certain height above the water.
• towing point is meant the position of the fulcrum of the cable on a device on board the ship, which is closest to the submerged end of the cable.
• the length of ducted cable in an aerial situation is increased compared to the simple towing height above the water because the cable is inclined relative to the vertical.
• the vertical direction in the terrestrial reference is represented by the z axis and the orientation of the section of certain hulls in zones A, B and C delimited by dashed lines is shown.
• the last hull 3 in engagement with the vessel is oriented vertically (trailing edge upwards) as shown in zone A.
• the hulls which are in the air between the pulley P and the surface of the water S are lying under the effect of gravity.
• the trailing edge of the hulls is oriented downwards (between the pulley P and the surface S of the water, the hulls have turned around the cable).
• the hulls in the water are rectified by the action of the water flow acting on the FO arrow as shown in the zone C (trailing and attacking edge located approximately at the same depth).
• This situation can be described as follows: between the towing point R and the surface of the water S, the fairing column performs a complete revolution in the direction of the arrow F1 around the cable.
• the fairing column 2 crosses the surface S and remains properly oriented on a certain length L1 of the order of a few meters or less sometimes.
• the fairing column 2 performs a complete turn in the water, in the opposite direction, represented by the arrow F2 to return to the correct orientation in the flow.
• the fairing undergoes a double complete twist around the cable.
• the double twist comprises a complete TA air twist, located above the surface of the water and a complete submerged Tl twist, located below the surface of the water. All the part of the fairing located below this double twist complete is no longer affected by what is happening above it (its hulls are correctly oriented in the flow).
• the Applicant has discovered that it is when a fairing undergoes a double complete torsion that, under certain conditions, the fairing will be strongly deteriorated in the water and this deteriorated part will cause great damage to the entire careened system during winding of the cable and more specifically during its passage in the cable guide device.
• the deteriorations will mainly consist of breaks in bonds between neighboring hulls.
• the Applicant has found that the submerged torsion can be considered as "hooked" on the cable.
• the position of the submerged torsion is fixed relative to the cable along the axis of the cable.
• its air counterpart, the aerial torsion remains located at the same place between the point of towing R and the surface of the water S. It is not fixed with respect to the cable along the axis of the cable but fixed by relative to the surface S of the water or the point of towing.
• hulls undergoing the submerged twist follow the movement of the cable that is hoisted up or down while the aerial twist remains fixed relative to the surface of the water.
• FIG. 2C shows a situation in which the cable has been unrolled with respect to the situation of Figure 2B (see arrow).
• the distance L2 represents the distance between the portion of the fairing concerned by the submerged torsion and the point of entry of the fairing into the water is greater than the distance L1 which represents the same distance in the situation of Figure 2B.
• the hulls pass in a direction other than that shown in Figure 2a in the pulley, they go upside down in the pulley, get stuck, and it is the whole fairing column that comes after the part of the fairing concerned by the old submerged torsion which is methodically destroyed if we continue the hoist because gradually, each hull follows the orientation of that which precedes it.
• the invention proposes a cable handling method which is based on this study of the phenomenon of double twist and which makes it possible to limit the risks of damage to the fairing of the cable.
• the subject of the invention is a method for handling a streamlined cable by means of a fairing, said cable being towed by a vessel on board which is fitted with a winch for winding and unwinding the faired cable. through a ducted cable guide device, the method comprising:
• a first cable monitoring step making it possible to detect whether the fairing undergoes a double twist around the cable comprising a complete submerged torsion and a complete aerial torsion
• the method comprises at least one of the following characteristics taken alone or in combination:
• the first step of hoisting comprises a step of lifting the cable during which the towing point of the cable is raised by means of a lifting device on board the ship,
• the method comprises a step of winding the cable by means of a winch on board the ship,
• the first monitoring step is implemented permanently or is repeated at time intervals below a threshold duration ds of not more than 10 minutes,
• a duration d separates the detection of the double torsion and the beginning of the first step of hoisting the cable, the sum of the threshold duration ds and the duration separating the implementation of the first monitoring step at the time of the detection and the previous implementation of the first monitoring step is not more than 15 minutes,
• the first hoisting step is carried out at least until the double torsion detected is absorbed
• the method comprises a first monitoring step making it possible to detect a double twist of the fairing implemented before each second hoisting step during which the cable of a length L greater than or equal to the sum of the cable is wound by means of the winch 1 meter and the altitude separating the towing point from the surface of the water,
• the first step of hoisting is carried out at least partially by means of a winch with a nominal speed of the winch, the method comprising, when the double torsion does not resorb during the first hoisting step, and if the winding of the cable of the length L involves the crossing of the guide device by submerged torsion, a third step of hoisting the cable during which the immersed torsion belonging to the detected double torsion passes through the guiding device, the third hoisting step being implemented at the means of the winch at a hoisting speed lower than the nominal speed, the third hauling step is assisted manually or mechanically so as to properly position the fairing in the guiding device,
• the first hoisting step is followed by a final hoisting step carried out by means of the winch at the rated speed of the winch until the length of the cable wound by the means winch reaches the length L,
• the method comprises, when no double torsion is detected during the first monitoring step, a second step of hoisting the cable of length L, carried out by means of a winch at the rated speed of the winch,
• the method comprises a second monitoring step implemented during the first hoisting step and making it possible to detect the resorption of the double torsion and to monitor the position of a complete submerged torsion relative to the guiding device,
• the method comprises fourth cable hoisting steps in which the cable of respective lengths shorter than the sum of 1 meter and the altitude separating the tow point from the surface of the water is wound up, the fourth hoisting steps being implemented at respective time intervals greater than or equal to at least 20 minutes during a predefined period, the cable not being unwound between two consecutive implementations of the fourth step,
• the method comprises a fifth hauling step of winding the cable of a length less than the sum of 1 meter and the altitude separating the tow point from the surface of the water to the length before at least one step of unwinding of the cable,
• the first hoisting step is implemented by means of a hoisting device, said hauling device being activated by automatically when the monitoring device detects a double twist.
• the invention also relates to a device for handling a streamlined cable by means of a fairing towed by a ship, said device comprising a monitoring device for detecting whether the fairing undergoes a double twist around the cable comprising a torsion complete submerged and complete aerial torsion and hauling device for hoisting the cable when a double twist is detected so that the complete submerged torsion at least partially out of the water and does not enter the guiding device.
• the device comprises an activation device for activating the hoisting by the hauling device and control means for controlling the hoisting of the cable so that the complete submerged twist at least partially out of the water and not does not enter the guiding device.
• the device comprises an alert device for alerting an operator when a double twist is detected.
• the invention also relates to a handling device configured to implement the method according to the invention, the monitoring device being configured to detect whether the fairing undergoes a double twist around the cable comprising a complete submerged twist and a complete twist and the hoisting device being configured to implement the first hoisting step when a double twist is detected by the monitoring device.
• the handling device comprises an actuator configured to activate hoisting of the cable by means of the hoisting device when a double twist is detected by the monitoring device and a controller making it possible to control hoisting of the cable by means of the hauling device. so that the complete submerged twist at least partially out of the water and does not enter the guide device.
• FIG. 1 has already been described, shows a section of ducted cable
• FIG. 1B already described represents an example of section of a hull of a fairing in a plane M perpendicular to the axis of the cable and represented in FIG. AT,
• FIG. 2A already described shows a towed towed cable partially immersed from its submerged portion to a guide pulley in a situation in which the cable is not subjected to double torsion
• FIG. 2B represents the cable of FIG. 2A in FIG. same state of immersion (that is to say winding and unwinding) as in Figure 2A but undergoing a double twist
• Fig. 2C shows the cable of Fig. 2A having the double twist of Fig. 2B in a configuration in which the cable has been unrolled with respect to Fig. 2B
• FIG. 2D shows the cable of FIG. 2A having the double twist of FIG. 2B in a configuration in which the cable has been hoisted with respect to FIG. 2B
• FIG. 3 represents a vessel towing a towed object by means of a towing cable
• FIG. 4 represents a block diagram of the steps of an exemplary method according to a first embodiment
• FIG. 5 represents a block diagram of the steps of an exemplary method according to a second embodiment.
• the invention relates to a method of handling a streamlined cable 1 towed by a naval vessel, such as a ship, to protect the fairing of the cable.
• a cable 1 may be a towing cable or electrotractor towed by a ship 100.
• the cable 1 is towed or towed by a ship. It is at least partially immersed.
• the cable comprises a fairing 3 comprising at least one fairing section comprising a plurality of hulls 2.
• the hulls of the same section of fairing are interconnected axially, that is to say along the towing cable. They are pivotally mounted around the cable and are hinged together by means of a coupling device so that the relative rotation of said hulls 2 relative to each other around the cable 1 is allowed. This clearance is allowed either freely with a stop. The rotation of a hull around the cable does not then cause the adjacent hull in rotation.
• the displacement can be obtained in a constrained manner with a more or less strong return to the aligned position (no relative rotation of the hulls relative to each other around the cable).
• the rotation of a hull around the cable rotates the adjacent hulls of the same section around the cable.
• the fairing comprises several sections
• the sections are free to rotate relative to each other around the cable.
• the hulls of a fairing section are connected in pairs by individual coupling devices. Each coupling device for connecting a hull to another hull adjacent to the same section fairing only.
• the cable tows a towed body 101, comprising for example one or more sonar antennas.
• the towed body 101 is mechanically secured to the cable 1 as appropriate.
• the launching and the exit of the water of the towed body 101 is carried out by means of a winch 5 arranged on a deck 103 of the ship 100.
• the winch 5 comprises a unrepresented drum dimensioned to allow the winding of the cable 1.
• the towed cable 1 can be wound around the winch 5 through a guiding device 4, as described above, for guiding the cable.
• the cable guide device also allows classically but not necessarily to orient the hulls relative to the drum winch. In addition, it conventionally makes it possible to secure the radius of curvature of the cable so that it does not fall below a certain threshold.
• the guiding device is a pulley 4. It could, for example, comprise, in place of or in addition to the pulley, at least one guiding means or guide allowing limit the lateral deflection of the cable such as a deflector, a hull reverser, a fairlead to secure the radius of curvature of the cable so that it does not fall below a certain threshold and / or a slicing device to properly store the cable on the drum.
• a lifting device 6 is shipped on board the ship 100 to raise and lower the towing point. It comprises, in the nonlimiting example shown in FIG. 3, an articulated structure 7, for example an arm, to which the pulley 4 is fixed.
• the articulated structure 7 is able to pivot about an axis perpendicular to the plane of the Figure, substantially parallel to the deck of the ship, that is to say a substantially horizontal axis when the ship is in equilibrium, to move from a low position, as shown in solid lines in Figure 3, in which the pulley (or more generally the towing point) occupies a low position, at a high position (shown in broken lines in FIG.
• the handling device is configured to allow water out of a cable length of between 1 m and 2 m.
• the invention aims to limit the risk that part of the fairing undergoing a complete submerged torsion does not enter the cable guide device.
• the method of handling the cable 1 comprises a first step of monitoring the fairing 1 to detect whether the fairing 2 undergoes a double twist comprising a complete submerged torsion and a complete air torsion and, when a double twisting of the fairing 2 is detected, a first step of hoisting the cable 1 of hoisting the cable 1, the first monitoring step and the first hoisting step being implemented so that the torsion immersed at least partially out of the water and does not enter the guiding device.
• the double twist is recent, that is, it has been formed for not more than 15 minutes, the torsion tightening of the fairing column is instantly reversible.
• the double twist is destabilized and suddenly it is undone at the same time as the aerial torsion.
• the fairing is then released from this double twist and returns to its nominal state and the system can be operated again in a nominal manner and, in particular, it is possible to immerse again the portion of cable that has been affected by the torsion immersed or to wind it around the drum of the winch without the guiding device being damaged.
• the double twist of the fairing does not break naturally ( or she may not get rid of it). Indeed, if the double twist is old, it has tightened. It follows that even if the hydrodynamic force is released, the double twist will not be undone. It will eventually, but after a while and as a result of relaxation of possible viscoelastic phenomena. Therefore, if the cable is hoisted too far, the complete submerged submerged torsion will occur at the towing pulley or the cable guide system at the towing point.
• the first hoisting step is thus performed so that the part of the fairing undergoing complete torsion immersed at the time of detection of the double twist does not enter the guide device. Consequently, the method according to the invention makes it possible, when it is used, either to resorb a double twist, or, when it does not resorb, to prevent a submerged twist from entering the guide.
• the method according to the invention therefore makes it possible to limit the risks of deterioration of the fairing due to the appearance of the double twists.
• the method according to the invention does not require modification of the device for winding and unwinding the cable (winch and guiding device).
• the method according to the invention is particularly advantageous when the guiding device is too narrow so that hulls which are not oriented trailing edge upward when they are presented to the guiding device, can turn around by pivoting around the cable axis, to reach this position.
• the guide device acts as a shaper.
• the first monitoring step 10 is implemented permanently or frequently for at least one towing the cable.
• the monitoring step is implemented permanently either by an automatic system or by the observation made by a crew member.
• the time between two implementations or successive achievements of the monitoring step less than or equal to 10 minutes and preferably less than or equal to 5 minutes.
• towing the cable 1 is meant a situation in which the cable comprises a submerged end and in which the ship is moving on the water.
• a first step of hoisting 1 1 of the cable 1 consists in hoisting the cable.
• the first lifting step 1 1 is implemented until resorption of the double twist or, more generally, at least until resorption of the aerial torsion.
• the method of the invention allows, without modification of the towing device, to take into account the appearance of twists to resorb without risking to grind the fairing. This method makes it possible to guarantee the disappearance of the grinding of a portion of the fairing column due to the formation of a double twist.
• the time between the beginning of the first hoisting step and the detection of the double twist is less than or equal to a threshold duration ds.
• the threshold duration ds is such that the sum of the threshold duration ds and the duration between the implementation of the first monitoring step at the time of detection and the previous implementation of the first monitoring step is at most equal to 15 minutes and preferably at most equal to 10 minutes.
• the length of time between implementation of the first monitoring step at the time of detection and previous implementation of the first monitoring step is zero when the first monitoring step is implemented permanently.
• the duration ds is between 5 and 10 minutes. This makes it possible to ensure that the double twist is always recent when implementing the first hoisting step 1 1, that is to say that it will disappear during hoisting. before the submerged torsion enters the guiding device. This method reduces the chances of grinding a portion of the fairing column due to the formation of a double twist. It allows to maintain the system without any interruption in operational condition.
• the first lifting step 1 1 comprises a lifting step 12 consisting in raising the towing point of the cable so as to bring the tow point to an altitude greater than the altitude it occupied at the time of detection of the double torsion by means of a lifting device.
• the lifting device is for example the lifting device shown in FIG. 1, in which case the articulated structure is pivoted from a low position to a high position in which the altitude of the tow point of the cable is greater than altitude of the tow point of the cable in the situation where the lifting device is in its low position.
• the stroke of the towing point of the cable during the lifting step 12 is fixed, it lies between 1 and 2 m. It makes it possible to guarantee the resorption of submerged twists extending to the stroke of the lifting device.
• the advantage of the lifting operation is to operate here a simpler maneuver than hoisting the cable by winding the cable by means of the winch, and above all, which absolutely does not risk damaging the fairing in case of double torsion old because the cable does not progress towards the guiding device. If it is simpler and safer, however, this maneuver will not be able to resorb a double twist whose submerged portion is at a depth greater than the stroke of the towing point between its upper position and its lower position.
• the method according to the first embodiment comprises, when the double twist is not resorbed at the end of the lifting step 12, a winding step 13 of winding the cable 1 by means of the winch 5 until resorption of the double twist. This step is performed when the lifting device is in the up position.
• the first hoisting step 11 comprises only the step of winding the cable, for example, when there is no lifting device.
• the first hoisting step includes only the lifting step.
• the first hoisting step 11 may be carried out so as to wind the cable of a predetermined length less than or equal to the altitude of the tow point in a calm sea state (that is to say when the axis boat is substantially horizontal in a terrestrial reference) plus 1 m. This is the minimum cable length separating the tow point from the entry point of the cable into the water. This feature ensures that a double twist just below the surface of the water does not enter the guiding device. In the latter case and in the case where the lifting step includes only the lifting step, the stroke of the lifting device being fixed, the unwinding of the cable is advantageously prohibited once the double twist is detected which limits the risks of increasing the depth of the submerged torsion.
• the method comprises, for example but not necessarily, after the first hoisting step 11, a deployment step consisting in deploying the cable.
• This step consists in putting the tow point back into the low position by means of the lifting device.
• the deployment step consists in putting the cable back into the deployed state in which it was before the first hoisting step. In this case, it further comprises a cable unwinding step.
• the method comprises a second monitoring step 14 making it possible to detect the resorption of the twist.
• This step must in fact make it possible to detect the resorption of the aerial torsion.
• This step is here implemented continuously during the first hoisting step. Alternatively, it could be implemented at regular time intervals or only at the end of the lifting step and at regular time intervals or continuously during the winding step of the cable.
• the method according to the first embodiment does not include this second step of monitoring the fairing. It is not necessary, for example, when the first lifting step includes only the lifting step since hoisting the cable by lifting makes it possible to raise the towing point without bringing the submerged torsion of the guide device closer together.
• the method according to the first embodiment makes it possible to avoid the passage of the double twists in the guiding device (that is to say before a major hoisting of the cable) and makes it possible to avoid deterioration of the fairing related to the tightening of the submerged twist with time.
• the first monitoring step can be performed episodically or randomly during towing or be performed in certain predetermined situations only during towing.
• the fairing is affected by a double twist.
• the method according to the second embodiment comprises a first fairing monitoring step 20 for detecting a double twist of the fairing carried out before each second cable hoisting step.
• length L greater than or equal to a threshold length Ls equal to the altitude of the tow point relative to the surface of the water plus one meter.
• the first monitoring step 20 follows a towing step of the cable 19 during which the winch 5 blocks the winding / unwinding of the cable. It is for example implemented after receiving a winding order of the cable of a length L.
• the second hauling step comprises a first hauling step 21 of the cable.
• the method advantageously comprises a second monitoring step 22 during the first hauling step 21.
• the second monitoring step 22 makes it possible to detect whether the double torsion resorbs, for example by detecting whether the aerial torsion is resorbed, and to monitor the position of the submerged torsion relative to the guiding device.
• the first hauling step is followed by a final hauling step 24, included in the second hauling step, of winding the cable by means of the winch up to the cable hoisted length can reach the length L.
• the winding of the cable can be continuous between the first hauling step and the final hauling step 24. It is advantageously carried out at the same speed.
• the second hauling step advantageously comprises a third step of hoisting of the cable 23 of continuing the first hoisting step during the crossing of the guide device by submerged torsion.
• the cable is not unwound, between the first hoisting step and the final hoisting step or between the third hoisting step and the final hoisting step.
• the first hauling step 21 comprises a winding step performed by means of a winch. It is advantageously performed at the nominal operating speed of the winch. This nominal speed is conventionally between 0.2 m / s and 1.0 m / s.
• This nominal speed is conventionally between 0.2 m / s and 1.0 m / s.
• the first step of hoisting is carried out at nominal speed and, for example, once the immersed torsion is completely out of the water and before that it enters the guide device, or when the submerged torsion partially leaves the water, begins the third stage of hoisting at a hoisting speed lower than the nominal speed.
• This third hoisting step can be assisted manually or mechanically to help the submerged torsion position itself correctly in the guide device because the guide device acts as a shaper.
• the cable winding is continuous between the first and the third hoisting step, but the hauling speed used during the third hauling step is lower than the hoisting speed used during the first hauling step.
• the third hoisting step is for example carried out at a speed at least two times lower than that at which the first hoisting step is performed. The advantage of performing this step at reduced speed is to limit the risk of deterioration of the fairing during its passage in the guiding device.
• the method may comprise a fairing repair step before the implementation of the third step.
• the hoisting of the cable is advantageously stopped until the double torsion is resorbed because of the viscoelastic effect before implementing the final hoisting step. 24.
• the portion of the cable undergoing the submerged twist can be manually recovered and deposited on the bridge between these steps to promote the resorption of the double twist. After this wait, the system returns to its nominal state and can be operated again in a nominal way.
• the hoisting step consists in taking up the winding of the cable where it stopped during the first step of hoisting until winding of the length L.
• the double torsion being resorbed and the hulls in good condition, the step of Final hoisting 24 can be performed at the rated speed of the winch.
• the first hoisting step may comprise a lifting step.
• the first hoisting step begins with a first lifting step and if the double twist does not resorb at the end of the lifting step, a step of winding the cable.
• the method then comprises a deployment step at the end of the first hoisting step or the third hoisting step.
• the first hoisting step comprises only one winding step.
• the monitoring step is followed by the second hoisting step 25 which can, for example, be carried out unattended and continuously at the speed nominal winch.
• the method comprises, during the towing of the cable, fourth steps of hoisting the cable 26 during which the cable is wound of respective lengths less than the threshold length Ls implemented at intervals of time at least equal to 20 minutes.
• the respective time intervals separating two fourth successive hoisting steps are greater than or equal to 20 minutes.
• the cable is not unrolled between two fourth steps of consecutive heaps.
• the fourth stages of hoisting allow to leave a possible submerged torsion of the water blind (that is to say without mobilization of the crew to carry out a possible monitoring).
• the fourth consecutive hoisting steps are spaced at least 20 minutes apart, if the double twist is out of the water, even if it is a double, remanent twist (i.e.
• the fourth hoisting steps therefore make it possible to absorb any double twists that would have formed on the surface and to limit the risks of detecting a double twist at the time of the monitoring step before hoisting the cable of a length greater than the length at least equal, that is to say greater than or equal to the threshold length Ls and therefore to limit the probability of having to implement the double torsion resorption procedure already described with reference to Figure 5.
• the fourth hoisting steps are advantageously carried out at regular time intervals (that is, two successive hoisting steps are separated by the same time interval).
• the cable winding lengths are the same during all the fourth steps.
• the time intervals and the winding lengths are different from one fourth step to another.
• the method comprises, before at least one unwinding step 28 of the cable, while the cable is partially immersed, a fifth hauling step 27, during which the cable is wound with a hauling length less than the threshold length. ls.
• This step makes it possible to absorb recent double twists and makes it possible to limit the risks of occurrence of old double twists. Like the previous step, it limits the risk of detection of double twists at the time of the first monitoring step.
• the fourth hoisting steps are carried out at respective time intervals at least equal to 20 minutes for at least one predefined period taken from a first period and at least a second period.
• the first period is a period extending from the beginning of the towing 19 to the first monitoring stage.
• a second period is a period extending between the end of a second hoisting step and the beginning of the first monitoring step subsequent to said second hauling step.
• the fifth hoisting step is carried out before an implementation step is carried out at least for at least one other predefined period taken from a first period and at least a second period.
• the fifth step is implemented before each unwinding step taking place during at least one other predefined period taken from a first period and at least a second period.
• the first hoisting step is implemented after detecting a double twist.
• the method has no unwinding step of the cable between the moment when the double twist is detected and the implementation of the first hoisting step.
• the monitoring steps to detect a double twist, to detect the resorption of a double twist and to monitor the distance between the submerged torsion of the guide device can be performed by visual inspection by the crew. Indeed, the aerial torsion is always visible by the ship's crew and the position of the submerged torsion relative to the guide device when it comes out of the water. It is effective but dependent on the attention of an operator.
• the main disadvantage lies in the immobilization of an operator who has to move in a back range and sometimes in difficult sea conditions and visions conditions that can be strongly degraded
• At least one monitoring step is performed by a monitoring device. This is particularly advantageous in the case of the first embodiment where continuous or frequent monitoring is necessary and this makes it possible to absorb recent double twists and to avoid the consequences of the old double twists.
• the invention also relates to a device for handling a streamlined cable towed by a ship.
• the device is able to implement the method according to the invention.
• the device includes a monitoring device for detecting whether the fairing undergoes a double twist around the cable including complete submerged torsion and complete aerial torsion.
• the handling device further comprises a hoisting device for implementing the first hoisting step.
• the hauling device makes it possible to hoist the cable when a double twist is detected so that the complete submerged torsion at least partially leaves the water and does not penetrate into the guiding device.
• the monitoring device is configured to implement the monitoring step or steps and in particular the first monitoring step.
• the monitoring device comprises for example an image sensor installed to capture images of the cable recurrently and an image processing device for detecting a double twist on the cable. It may alternatively comprise a capacitive detector extending within the hulls along the cable which crashes and whose capacity varies during the torsion of the hulls.
• the monitoring device comprises for example a computer receiving the capacity of the detector and comparing it to a predetermined threshold. For example, the double twist is detected when the capacitance of the detector exceeds a first predetermined threshold.
• the monitoring device advantageously makes it possible to detect the disappearance of a double twist and possibly to monitor the distance between the submerged torsion and the guiding device.
• the disappearance of the double torsion is for example detected when the capacitance of the detector falls below a second predetermined threshold which may be, without limitation, the first threshold.
• the monitoring device is configured to detect the disappearance of a double twist and possibly to determine the distance between the submerged torsion and the guide device.
• the hoisting device comprises for example a winch and possibly a lifting device as claimed previously.
• the handling device is configured to implement the method according to the invention.
• the monitoring device is configured to implement the one or more monitoring steps of the invention. This implementation is performed at the desired times described in the present patent application (at a predetermined time interval and / or before each second hoisting step of a length L greater than or equal to a predetermined length).
• the handling device comprises a hoisting system configured to implement the first hoisting step when a double twist is detected by the monitoring device.
• the hoisting system is advantageously configured to implement the other hoisting step (s) according to the invention.
• the hoisting steps are implemented at the desired times described in this patent application.
• the hoisting system comprises the hoisting device and an activating device or actuator for activating, or configured to activate, the first step of hoisting the cable by means of the hauling device when the double twist is detected and means of control, or controller, for controlling, or configured to control, the hoisting step (s) and in particular the first step of hoisting the cable so that the complete submerged twist is at least partially out of the water and does not penetrate the guiding device.
• the control device comprises for example a control device for controlling the hoisting device so as to perform the first hoisting step.
• the controller can be the actuator.
• the monitoring device is advantageously configured so as to make it possible to implement the second monitoring step, or configured so as to implement the second monitoring step, that is to say to detect the disappearance a double twist and / or the water outlet of a double immersed torsion and / or to compare the position of the submerged torsion with that of the guide device.
• the controller receives the information from the monitoring device.
• the handling device comprises an alert device for alerting an operator when a double twist is detected.
• the warning device is configured to alert the operator when a double twist is detected.
• the operator then actuates and controls the hoisting device so as to implement the first hoisting step.
• the second monitoring step is then, for example, performed by visual inspection.
• the invention also relates to a cable system comprising a streamlined cable and a handling device according to the invention.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Ocean & Marine Engineering (AREA)
• Laying Of Electric Cables Or Lines Outside (AREA)

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• 2015
  • 2015-02-27 FR FR1500385A patent/FR3033162B1/fr active Active
• 2016
  • 2016-02-26 US US15/553,031 patent/US10457356B2/en active Active
  • 2016-02-26 AU AU2016223409A patent/AU2016223409B2/en active Active
  • 2016-02-26 WO PCT/EP2016/054146 patent/WO2016135321A1/fr active Application Filing
  • 2016-02-26 SG SG11201706876WA patent/SG11201706876WA/en unknown
  • 2016-02-26 CA CA2977706A patent/CA2977706A1/en active Pending
  • 2016-02-26 ES ES16707094T patent/ES2937643T3/es active Active
  • 2016-02-26 EP EP16707094.5A patent/EP3261976B1/de active Active

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