Steering gear regulations emphasize redundancy to ensure ships maintain steering capability even during system failures. The key redundancy requirements include:

## Main and Auxiliary Steering Gear

Every ship must be equipped with both main and auxiliary steering gear systems. These systems must be arranged so that the failure of one does not render the other inoperative[3].

## Power Units and Control Systems

### Main Steering Gear

For passenger ships, the main steering gear must be capable of operating the rudder as required even with one power unit out of operation. In cargo ships, the main steering gear must be able to operate the rudder as required while all power units are functioning [3].

### Auxiliary Steering Gear

An auxiliary steering gear is not required if the main steering gear comprises two or more identical power units, provided certain conditions are met[3].

## Control Systems

Two independent control systems must be provided for the main steering gear, both operable from the navigation bridge. In tankers, chemical tankers, or gas carriers of 10,000 gross tonnage and upwards, a second independent control system is required even if the primary system is a hydraulic telemotor[3].

## Power Supply

Steering gear control systems operable from the navigation bridge must have their own separate power supply circuits. For ships with rudder stocks over 230 mm in diameter, an alternative power supply must be provided automatically within 45 seconds[3].

## Special Requirements for Large Ships

### Tankers, Chemical Tankers, and Gas Carriers (10,000 GT and above)

The main steering gear must comprise two or more identical power units. The system must be arranged so that steering capability can be maintained or quickly regained in the event of a single failure in any part of one power actuating system[3].

### Ships of 70,000 GT and above

These vessels must also have main steering gear comprising two or more identical power units[3].

## Failure Isolation and Recovery

Systems must be designed to isolate defects quickly and maintain or regain steering capability after a single failure. For hydraulic systems, loss of hydraulic fluid from one system should be detectable, and the defective system must be automatically isolated to keep other systems operational[3].

These redundancy requirements ensure that ships maintain steering capability even in the event of system failures, enhancing overall safety and maneuverability.

Citations:

[2] https://imorules.com/GUID-CF547534-23B3-4162-8415-6C806370E406.html

[3] https://imorules.com/GUID-CF547534-23B3-4162-8415-6C806370E406.html

Steering Gear Block Diagram:

.steering gear block .steering block  .block diagram

EXPLAINATION OF STEERING GEAR BLOCK DIAGRAM:

1.SHIP HEADING IS DETECTED FROM GYRO & COMPARATOR COMPARE THE PRESENT COURSE & REQUIRED COURSE FROM COURSE SET CONTROLLER.

2.AFTER COMPARATOR SIGNAL IS GOING TO ERROR AMPLIFIER. FROM ERROR AMPLIFIER TO TELEMOTOR SIGNAL TRANSMITTER.

3.TELEMOTOR SIGNAL RECEIVER IN STEERING GEAR ROOM.

4.THEN THIS SIGNAL IS GOING TO SOLINOID V/V. FROM SOLINOID V/V SIGNAL GOES TO DIRECTIONAL V/V.

5.FROM DIRECTIONAL V/V SIGNAL IS GOING TO RUDDER STOCK.

6.RUDDER ANGLE TRANSMITTER TRANSMIT THE SIGNAL TO RUDDER ANGLR INDICATOR & ALSO TO THE ERROR AMPLIFIER.WHICH ACT AS A FEED BACK ACTION