• Subsea Knuckle Boom Crane

    Description

    Crane-installed AHC systems from NOV`s Hydralift group have been in operation since the mid- 1980`s.

    NOV`s Hydralift AHC systems can help minimize your subsea operations costs by reducing “down time” caused by severe weather conditions. The AHC systems has been designed for subsea load handling from vessel or rig. Cranes and other handling systems with AHC exceed the weather window when compared to conventional systems, and ensure a smooth landing or lift off even under severe weather conditions.

    NOV provides it line of high performance Hydralift AHC systems with a very high focus on safety. These systems have been developed in compliance with applicable international rules and standards. References from major companies worldwide are available on request.

     

     

    Features/Benefits

     

    • Increased Weather Window: The system is designed to compensate for actual wave height, thereby increasing the weather window for the vessel which in turn reduces "down time".
    • Intelligent Load Handling: The system detects all vessel motions and loads and automatically provides transitions to other modes. Landing and lift off will occur at the most appropriate moment. This prevents excessive tugging on the wire and lifting straps. It also prevents load collision with the seabed or other objects.
    • High Compensation Grade: The National Oilwell Varco Hydralift™ AHC system offers a compensation grade of approximately 97%. If the boom tip has a vertical motion of 3 meters, the load will move only 0.09 meter relative to the sea bottom.
    • Reduced Power Consumption: By using an accumulator pressure vessel (APV) system containing air or nitrogen to recover energy, the power requirement from the vessel is reduced by 75%.
    • Limiting of Dynamic Forces: The AHC system will limit the dynamic forces on the system during landing and lift off operation.

     

    Specifications

    Typical Range:

     

    • Safe Working Load SWL: up to 500mT
    • Working radius: up to 55m