Linear Active Heave Compensator

Content

Linear Active Heave Compensation Systems (LAHC) are intelligent solutions for standard winch-driven cranes and hoists that deposit loads to cavernous locations or onto the seabed. The system fits with nearly every existing winch system as an add on, consuming considerably less energy than other active heave systems.

In LAHC the Motion Reference Unit measures the heave motion at the location where the winch rope leaves the vessel, then compensates it with a special cylinder that combines both active and passive compensation capabilities. This cylinder pays out the wire when the vessel lifts up, and hauls the wire when the vessel lowers.

The LAHC concept provides the opportunity to further reduce the required power by combining both passive and active compensation in one system. The passive part accounts for the average load while the active part compensates for the wave-induced load variations.

Modules of Linear AHC

One important advantage: we designed LAHC to be modular, making it easy to integrate it into nearly every vessel arrangement. It consists of four main modules:

  • Cylinder-based integrated cable actuation system
  • Hydraulic Power Supply
  • High Pressure Air System
  • Integrated Control System

Based on a closed force loop LAHC requires only a simple mechanical interface for the vessel structure, compensating more the 90% of the heave motion. Choosing our containerised option enables you to use LAHC anywhere in your fleet of similar vessels. The modular approach allows built-in flexibility for your individual systems.

Advantages

  • Significant reduced power consumption in compare with alternative AHC controlled winches.
  • Residual motion at depth 10 %
  • High level of accuracy
  • Easy integration in any existing winch system.
  • Containerized option enables multiple use within a fleet of similar vessels.
  • The principle of LAHCS is based on a closed force loop, and therefore requires relatively simple mechanical interface to the vessel structure.
  • Modular approach allows build-in flexibility with respect to the actual vessel arrangement.