Method for laying and/or recovering a flexible line in a body of water and associated system

A flexible line laying and/or recovering system in a body of water, comprising:

• a laying device comprising a pair of upper tensioners and a pair of lower tensioners, the pair of upper tensioners and the pair of lower tensioners each defining a circulation passage of the line in which the line is locally clamped;
• each tensioner of the pair of upper tensioners and of the pair of lower tensioners comprising a line mover for moving the line and a motor for setting the line mover in motion, the motor configured to be activated to deliver a line moving torque;
• a controller of the motor, configured to carry out:
• at least one line laying and/or line recovery in which the controller activates the motor of at least one tensioner of the pair of upper tensioners and the pair of lower tensioners and delivers a movement torque, said movement torque generating a continuous movement of the line through each circulation passage;
• at least one near-immobilization or immobilization of the line;
• the at least one near-immobilization or immobilization of the line comprising:
• the controller activating the motor of at least one upper tensioner and/or at least one lower tensioner, to apply, to the line mover of the upper tensioner and/or of the lower tensioner, a torque for holding the line against a weight of the line,
• the controller at least occasionally controlling at least one motor of an upper tensioner of the pair of upper tensioners and/or of a lower tensioner of the pair of lower tensioners:
• to cause a line mover of the upper tensioner and/or the lower tensioner to move, or
• to change the holding torque applied to the line mover of the upper tensioner and/or of the lower tensioner without moving the line mover of the upper tensioner and/or lower tensioner.

A method for laying and/or recovering a flexible line in a body of water, comprising:

• providing a laying device comprising a pair of upper tensioners and a pair of lower tensioners, the pair of upper tensioners and the pair of lower tensioners each defining a passage for circulation of the line in which the line is locally clamped, each tensioner of the pair of upper tensioners and of the pair of lower tensioners comprising a line mover and a motor for setting the line mover in motion, the motor being configured to deliver a line moving torque;
• a controller of the motor,
• the method comprising:
• at least one line laying and/or line recovery in which the controller activates the motor of at least one tensioner of the pair of upper tensioners and of the pair of lower tensioners and delivers a movement torque, said movement torque generating a continuous movement of the line through each circulation passage;
• at least one near-immobilization or immobilization of the line;
• the at least one near-immobilization or immobilization of the line comprising:
• the controller activating the motor of the upper tensioner and/or the lower tensioner, to apply, to the line mover of the upper tensioner and/or of the lower tensioner, a torque for holding the line against a weight of the line,
• the controller at least occasionally controlling at least one motor of an upper tensioner of the pair of upper tensioners and/or of a lower tensioner of the pair of lower tensioners:
• to cause the line mover of the upper tensioner and/or the lower tensioner to move, or
• to change the holding torque applied to the line mover of the upper tensioner and/or of the lower tensioner without moving the line mover of the upper tensioner and/or lower tensioner;
• and
• immobilizing the line, immobilizing the line comprising a succession of holding intervals of holding the line immobile in which the motors of at least one upper tensioner of the pair of upper tensioners and of at least one lower tensioner of the pair of lower tensioners apply the holding torque to the line without moving the line movers of the at least one upper tensioner and/or of the at least one lower tensioner, and load regulation intervals in which a motor of an upper tensioner of the pair of upper tensioners or of a lower tensioner of the pair of lower tensioners is active to cause:
• the line mover of the lower tensioner and/or the upper tensioner to move or
• the holding torque applied to the line mover of the upper tensioner and/or the lower tensioner to change without movement of the line mover of the upper tensioner and/or lower tensioner, wherein during the immobilizing, a mechanical brake is permanently applied to at least one upper tensioner of the pair of upper tensioners to immobilize the upper tensioner, and wherein during each regulation interval, the motor of the at least one lower tensioner is activated to cause the line mover of the lower tensioner to move or cause the torque applied to the line mover of the lower tensioner to change without moving the line mover of the lower tensioner,
• or wherein, during the immobilizing, a mechanical brake is permanently applied to at least one lower tensioner of the pair of lower tensioners to immobilize the lower tensioner, and wherein during each regulation interval, the motor of the at least one upper tensioner of the pair of upper tensioners is activated to cause the line mover of the upper tensioner to move or cause the torque applied to the line mover of the upper tensioner to change without moving the line mover of the upper tensioner.

A method for laying and/or recovering a flexible line in a body of water, comprising:

• providing a laying device comprising a pair of upper tensioners and a pair of lower tensioners, the pair of upper tensioners and the pair of lower tensioners each defining a passage for circulation of the line in which the line is locally clamped, each tensioner of the pair of upper tensioners and of the pair of lower tensioners comprising a line mover and a motor for setting the line mover in motion, the motor being configured to deliver a line moving torque;
• a controller of the motor,
• the method comprising:
• at least one line laying and/or line recovery in which the controller activates the motor of at least one tensioner of the pair of upper tensioners and of the pair of lower tensioners and delivers a movement torque, said movement torque generating a continuous movement of the line through each circulation passage;
• at least one near-immobilization or immobilization of the line;
• the at least one near-immobilization or immobilization of the line comprising:
• the controller activating the motor of the upper tensioner and/or the lower tensioner, to apply, to the line mover of the upper tensioner and/or of the lower tensioner, a torque for holding the line against a weight of the line,
• the controller at least occasionally controlling at least one motor of an upper tensioner of the pair of upper tensioners and/or of a lower tensioner of the pair of lower tensioners:
• to cause the line mover of the upper tensioner and/or the lower tensioner to move, or
• to change the holding torque applied to the line mover of the upper tensioner and/or of the lower tensioner without moving the line mover of the upper tensioner and/or lower tensioner;
• immobilizing the line, immobilizing the line comprising a succession of holding intervals of holding the line immobile in which the motors of at least one upper tensioner of the pair of upper tensioners and of at least one lower tensioner of the pair of lower tensioners apply the holding torque to the line without moving the line movers of the at least one upper tensioner and/or of the at least one lower tensioner, and load regulation intervals in which a motor of an upper tensioner of the pair of upper tensioners or of a lower tensioner of the pair of lower tensioners is active to cause:
• the line mover of the lower tensioner and/or the upper tensioner to move or
• the holding torque applied to the line mover of the upper tensioner and/or the lower tensioner to change without movement of the line mover of the upper tensioner and/or lower tensioner;
• and
• measuring information representative of a difference in load between a load applied to at least one upper tensioner of the pair of upper tensioners and a load applied to at least one lower tensioner of the pair of lower tensioners, a movement of the line mover of the lower tensioner and/or upper tensioner by the motor during each control interval, or the torque applied to the line mover of the lower tensioner and/or the upper tensioner by the motor during each regulation interval being controlled as a function of the information.