System configuration and Functions.

1. In both the 1-ram 2-cylinder and the 2-ram 4-cylinder types, the rudder actuator has a total capacity (torque) to be equivalent to the 100% of design capacity and the power system is completely doubled.

2. When a single failure, such as the oil leakage, occurs in the piping system, the low oil level detector of the oil tank to be connected to the power system in operation is actuated to send an alarm to the bridge and engine room. The valve adjustment of A~F on the next page diagram is then done manually in the steering gear room in order to isolate the malfunctioning hydraulic system. Thus maintaining stable operation of the power system. In this manner, steering capacity is maintained.

3. It is satisfies the IMO regulation for the tankers of 10000 GT or more, that the valves A and B Change to the automatic isolation valves. In that case, when a single failure, such as the oil leakage, occurs in the piping system, by the low oil level detector of the oil tank to be connected to the power system in operation, the other power system is simultaneously operated automatically or remotely. At the same time, the circuit isolation valves between the circuits actuate to isolate the malfunctioning piping system automatically. Thus, the steering capability is maintained. And the power system on the malfunctioning piping system is stoped automatically by the second low level detector, At the same time, the related isolation valve also returns to its original position.

4. Alter the single failure to be described above, the capacity of rudder actuator is reduced to the half of design capacity. It is necessary to reduce ship's speed to the half of max. speed or below 7 knots.