General Engineering Flashcards

What is the primary purpose of a ship's oily water separator (OWS)?

Answer: To separate oil from bilge water before discharge overboard

An OWS removes oil from bilge water so the effluent meets the 15 ppm standard required by MARPOL Annex I before discharge.

What is the correct procedure when a relief valve on a high-pressure system lifts unexpectedly?

Answer: Shut down the system and investigate the cause before restarting

An unexpected relief valve lift signals an overpressure condition; the system must be shut down and the root cause identified to prevent equipment damage or injury.

Which bearing type is most commonly used for a ship's main propulsion shaft?

Answer: White metal (babbitt) journal bearing

White metal (babbitt) journal bearings are used for main propulsion shafts because they can carry large radial loads and are self-lubricating with oil or water.

What does a 'load cell' measure in marine engineering applications?

Answer: Force or weight applied to a structural member

A load cell is a transducer that converts mechanical force or weight into an electrical signal, used in applications like mooring line tension monitoring.

What is the function of a 'stern tube' on a vessel?

Answer: Houses the propeller shaft where it passes through the hull

The stern tube is a watertight housing that supports and seals the propeller shaft as it passes through the vessel's hull.

In a refrigeration system, what is the role of the expansion valve?

Answer: Reduces refrigerant pressure to cause it to cool and absorb heat

The expansion valve reduces refrigerant pressure, causing it to expand and evaporate in the evaporator, absorbing heat from the refrigerated space.

What is the purpose of a 'deaerator' in a marine steam system?

Answer: To remove dissolved oxygen and other gases from feedwater

A deaerator removes dissolved oxygen and carbon dioxide from boiler feedwater, preventing corrosion of the boiler and steam piping.