Considerations regarding the laboratory testing of electro-hydraulic heave compensators

Abstract

The unpredictable weather and the movements of the floating ships transform the marine environment into one of the most hostile working environments on the planet. Movements of lifting / lowering of vessels / platforms carrying cranes or drilling rigs, caused by the disturbing dynamics of the waves, varying in force, frequency, direction and amplitude, affect the precise positioning of the loads, lead to premature wear of the drilling holes, and endanger the integrity or even the life of the crew members. Due to the resonance in the cable of the load lifting system, caused by the movement of the vessel on a rough sea, the tension in the cable can increase more than 100 times. The safety and protection engineering solution is force compensation, that is the decoupling of the vertical movement of the ship from the one of the floating load. The authors present an experimental model, with the generator and the heave compensator at a small scale, which will simulate in the laboratory the operating modes of heave compensation systems very close to the real ones, existing on ships.