Abstract: A marine installation system for installing an item on a riser includes a cable extending between two supporting points, the cable being inclined relative to the horizontal; a first ROV arranged to mount the item on the cable at a first position; and a second ROV arranged to remove the item from the cable at a second position, and to install the item on the riser.

Abstract: A marine installation system for installing an item on a riser includes a cable extending between two supporting points, the cable being inclined relative to the horizontal; a first ROV arranged to mount the item on the cable at a first position; and a second ROV arranged to remove the item from the cable at a second position, and to install the item on the riser.

Abstract: A method of removing a flexible line deployed between an offshore platform and a subsea structure, where the platform has a landing deck on which the flexible line is installed, the landing deck facing away from the platform towards an installation side. The method comprises: decoupling a topside end of the flexible line from the landing deck; lowering the topside end from the landing deck to the sea bed using a platform mounted winch, and detaching the winch from the topside end; moving the platform in a direction away from the installation side and positioning an installation vessel on the installation side; lowering a recovery line from the installation vessel and attaching an end of the recovery line to the topside or subsea end of the riser; raising the attached topside or subsea end onto the installation vessel from the seabed using the recovery line; and recovering the flexible line onto the installation vessel, whereupon the platform can be moved back to an operating position.

Abstract: A method of installing a flexible line between an offshore platform and a subsea structure and a method of removing a flexible line deployed between an offshore platform and a subsea structure. The method of installing includes at least partially deploying the line in the water using an installation vessel located outside of an exclusion zone in the vicinity of the platform, including lowering a topside end of the line either to the seabed or to an intermediate location between the seabed and the platform. The method further includes pulling the topside end to a position within the exclusion zone and winching the topside end up to the platform, and coupling the topside end to the platform.

Abstract: A method of removing a flexible line deployed between an offshore platform and a subsea structure, where the platform has a landing deck on which the flexible line is installed, the landing deck facing away from the platform towards an installation side. The method comprises: decoupling a topside end of the flexible line from the landing deck; lowering the topside end from the landing deck to the sea bed using a platform mounted winch, and detaching the winch from the topside end; moving the platform in a direction away from the installation side and positioning an installation vessel on the installation side; lowering a recovery line from the installation vessel and attaching an end of the recovery line to the topside or subsea end of the riser; raising the attached topside or subsea end onto the installation vessel from the seabed using the recovery line; and recovering the flexible line onto the installation vessel, whereupon the platform can be moved back to an operating position.

Abstract: A method of installing a flexible line between an offshore platform and a subsea structure includes at least partially deploying the line in the water using an installation vessel located outside of an exclusion zone in the vicinity of the platform, including lowering a topside end of the line either to the seabed or to an intermediate location between the seabed and the platform. The method further includes pulling the topside end to a position within the exclusion zone and winching the topside end up to the platform, and coupling the topside end to the platform.

Abstract: A method of matching message elements, including a reading step of reading a contents of a first message and a second message and a determining step that determines whether the content of the first message is the same as the content of the second message, wherein if the content of the first message matches the content of the second message, a new pair is formed that includes the content of the first message and the content of the second message. The method further includes a matching table lookup step of reading a matching table, which stores one or more pairs of matching elements, a consistency check step to determine whether the new pair is consistent with the one or more pairs of matching elements stored in the matching table, and a storage step for storing the new pair to the matching table based on the result of the consistency check step.