Question

(a) Suggest four reasons why the temperature of the oil in the steering gear system may become excessive.

(b) With reference to steering gears explain how the ship may be steered in each of the following circumstances

(i) Destruction by fire of the primary supply cable

(ii) Destruction by fire of the telemotor lines

(iii) Bearing failure in the running pump

Answer 1

Part (a)

Four reasons why the temperature of the oil in the steering gear may become excessive are:

If there isn't enough oil circulating in the system, there will be inadequate cooling, leading to a rise in temperature.
Entrapped air in the hydraulic lines can cause the system to overheat due to cavitation and inefficient heat dissipation.
Excessive or continuous operation under heavy load conditions, such as manoeuvring in rough seas, can cause the system to overheat.
Using oil that is too viscous or not suited for the temperature range of the system can cause excessive heat generation during operation.
Wear in the hydraulic components, such as pumps or valves, can result in increased friction, which generates excess heat within the system.

Part (b)

(i) Steering gear requires to have a separate power supply and motor, one supply for each pump. the primary supply from the main switchboard, and the secondary or emergency supply from the emergency switchboard. So if the primary supply was to be destroyed by fire in this case, the secondary or emergency supply would still be in operation

(ii) If telemotor lines are destroyed by fire, the emergency steering arrangement would have to be used where the ship is navigating from the steering flat, using communication between the bridge and the steering flat. Emergency steering designs vary from ship to ship

(iii) If there was bearing failure on the running pump and the pump were to stop, the standby pump would start up automatically, and steering would resume as normal from the bridge. the pump that bearing failure occurred on would be isolated.

✓ Verified Model Answer (Text Solution)

Four reasons why the temperature of the oil in the steering gear may become excessive are: