Thanks to the application of a submersible pump as soil intake technology without suction pipeline, it is possible to extract and handle the pulp with the sand output up to 30% by volume of nominal capacity. This dredger can recover 100 m3 of wet sand and discharge it to the dumpsite located at the distance of up to 500 m, while the dredger pump power consumption is 75 kW. The depth of dredging reaches 30 meters. The total installed power of the dredger is 135 kW. Dredger power supply - three-phase, from the shore 400 V grids.
The system of the dredger electric equipment and automation ensures all electro-technic protection measures, as well as control of current consumption and input voltage. The dredger is protected against possible heeling and water availability in bilges. The device detecting the availability of water in pontoons will inform the staff about its penetration. The dredger can work in semi-automatic mode employing an industrial programmable logic controller which ensures the operation within the range of admissible pump current consumption and in permanent contact with the soil.
The dredger is equipped with a water jet system comprising a 37 kW centrifugal pump and a jet ring with nipples mounted directly on a dredge pump. The jet pump ensures the water capacity of 100 m3/h and creates the pressure of minimum 8 bars which are sufficient to loosen compressed soils with clayish inclusions. This technology makes it possible to continuously pump water-sand mixture with a high density. Thus, hydraulic excavation operations are carried out with high efficiency. The dredger construction is designed as trimaran with the installation of the dredge pump at the suspension at the forepart of pontoons. Lifting and submerging of the pump is carried out by means of winch through gantry with a block mechanism. To ensure smooth lifting and submerging, the pump winch drive is equipped with a frequency converter.
The dredger transportation and maneuvering within the water body are carried out using four mooring winches installed on side pontoons in the corners of a dredger. The dredger has got a modular design, thus, it can be transported by trucks. To assemble a dredger, 1-2 days are sufficient. The dredger is easy in operation maintenance. The spare parts’ replacement is carried out directly on the dredger without the need to dismount the pump. The maintenance personnel for the dredger should include 2 employees including the servicing of the discharge site. If necessary, the dredger can be equipped with discharge pipelines from PE, power cable, and steel pontoon-type floaters.