SOLUTION FOR THE VIBRATION CHALLENGES ON CUTTER SUCTION DREDGERS

摘要

Van Oord's powerful cutter suction dredger Athena was built by IHC Dredgers for dredging in hard soil. The strong vibrations on this type of dredger are notorious for their negative effects on the working and living conditions on board. Van Oord's global dredging experience, IHC's drive to build innovative dredgers and Loggers' know-how of shock, vibration and noise control were combined in the development of an innovative solution, that puts an end to this problem most major dredging contractors are facing. A fully automated system continuously monitors and controls air springs providing horizontal and vertical stabilization of the deck house during operation. As traditional vibration mounts only isolate vibrations from 9 Hz, the Athena required an advanced solution isolating also the low frequencies the crew is exposed to. The completely new solution isolates vibrations starting at 2 Hz that would otherwise be transferred from the cutter head, through the hull to the crew in the accommodations. It also isolates the shocks induced when the cutter head sets its teeth into a newly encountered piece of rock. These capabilities make all the difference between shaky and noisy working conditions and a safe and quiet environment on the Athena. Important factors need to be taken into account when setting a heavy deck house afloat on air, such as safety precautions, forces inflicted on the deck house caused by ship movements and wind. By sharing their experience in dredging projects and valuable input data, Van Oord and IHC enabled Loggers' engineers to perform accurate simulations of the system under different circumstances. In practice, not only the crew benefits from the calm as predicted by the simulation, but their employer as well. With the Athena Van Oord complies with strict local laws and regulations while strengthening the company's image as an employer of choice.