The hydraulic power unit for LNG Carrier consists of two main hydraulic pumps/motors, one hydraulic topping up pump/motor, filters, gauges, electric & hydraulic components, control panels, and so on. There are two main pumps : one is for mormal operation; another one is for back up operation. When the standard pressure level is under abnormal condition, the standby pump automatically runs in order to maintain the normal pressure level. The hydraulic topping up pump is designed to preserve the whole system pressure level when no valve is under operation. Normally, the hydraulic power units of LNG uses 'piston type pumps' & 'self-regulating type pumps' which keep the hydraulic pressure the standard condition. It supplies the constant pressure in the circuit when the pump runs.

'Solenoid valve deck box for Emergency Shut Down (ESD) system' or 'Solenoid valve deck box' is installed in the passage way or the pump/ machinery room of the hazardous area for LNG carrier. It is constructed to operate the valve and to process the signal. For the ESD system of valve operation, the ESD valves can be controlled the same as the other valves under the normal operating condition. When ESD solenoid valve is energized, it makes the oil way closed from ESD solenoid valve to closing chamber of the corresponding actuators. When the ESD solenoid valve under ESD condition, however, is dis-energized, it makes the oil way opened from ESD solenoid valve to closing chamber of the corresponding actuator. Consequently, ESD valves are automatically shut down at ESD condition. The hydraulic power for closing ESD valves at ESD condition is supplied from the hydraulic accumulators. Normally, the capacity of accumulators has the enough power in order to allow the corresponding ESD valves work 2 strokes.

T"Control console" operates and monitors the valve remote control system and position indication via switches and lamps installed on "Mimic" plate. And control console monitors the tank level gauging system, cargo monitoring system and various related equipment. And it's possible to organize the equipment by shipyard's request optionally.