Abstract: The present invention relates to a submarine data relay system that enables smooth and stable wired data relay without interruption of data transmission even in harsh undersea conditions. The system includes: a main system placed on the water, generating control data and transmitting the control data into water, and collecting data generated in water; a plurality of relay devices placed at different depths, delivering control data from the main system to corresponding sensor units to support measurement, and collecting measurement data from the sensor units and transmitting the measurement data to the main system; an operational line connecting the main system and the relay devices in series for data transmission and power delivery; and an emergency line connecting the main system and every second relay devices, wherein when a break occurs at a section of the operational line, the broken section thereof is replaced with the emergency line.

Abstract: A lifting pump for manganese nodules includes: a cylindrical body that is sealed at upper and lower portions thereof by a semi-spherical upper cap having a fluid outflow port and a cable insertion tube, and by a semi-spherical lower cap to which an inflow case of a pump unit is coupled; a pumping motor that has a fluid passage formed between an inner surface of the body and an outer surface thereof, is vertically fixed in the body, and drives the pump unit using electric power supplied through a cable; a cover that provides a seal around a shaft of the pumping motor; the pump unit that is installed between the shaft of the pumping motor and the semi-spherical lower cap, is driven by the rotation of the pumping motor, and lifts seawater together with the manganese nodules; a sealing means that provides a seal between the pumping motor and the pump unit; and a reducer that is coupled to the bottom of the pump unit and guides the seawater including the manganese nodules to the pump unit.