What is Main Propulsion Plant

Main Propulsion Plant

The power is being develop from the main engine and transfer the torque to the
propeller via the shafting arrangement. This is the main plant in the engine room that
provides power to propel the ship. When in operation, the watch keeper’s monitors
and records various parameters such as pressure, temperatures etc. Any
discrepancy of parameters from operating standards is being rectified.



 Shafting Arrangement

To transmit the power of the main engine to the propeller, shafting arrangement is
provided. The number of shafts and bearings varies depend on the design of the
ships. In the modern ships, there is one thrust shaft, one or more intermediate shaft
and a propeller shaft which are all supported by bearings.
a. Thrust shaft is the shaft next to main engine which is connected to the flywheel
and supported by the thrust bearing. The main purpose is to transmit the
rotational thrust of the main engine connecting rod to the propeller. The thrust
bearing maintains the alignment of the thrust shaft and absorb the axial thrusts
that are being generated during transmission of force.
b. The intermediate shaft is the intermediary shaft between the thrust shaft and the
propeller shaft. One or more intermediate shaft is connected and the number
 depends on the length of the engine to the propeller. The intermediate shaft is
supported by an intermediate bearing and the plummer block.
c. The propeller shaft is the last shaft connected in the shafting arrangement. One
end of the shaft is tapered and where the propeller is seating. The propeller shaft
is supported by the stern tube bearing with seals to prevent sea water leakage to
the engine room