PWR-307 INTERVENTION

Which feature makes water tube boilers more suitable than fire tube boilers for high-capacity applications?

• Compact design and easy maintenance

• Ability to handle higher steam pressure and temperature

• Lower cost of construction

• Reduced fuel consumption for smaller systems

What is the primary function of a boiler in marine engineering?

• To generate steam for propulsion and auxiliary operations

• To transfer heat from the ship's engine to the cargo

• To store water at high pressure for engine cooling

• To provide electricity for onboard systems

How does the heat transfer process in a fire tube boiler differ from a water tube boiler?

• Water flows inside tubes, and hot gases surround them.

• Both water and gases mix in a central chamber.

• Heat transfer occurs through convection only.

• Hot gases pass inside tubes surrounded by water.

What is the main role of "downcomer tubes" in water tube boilers?

• They carry steam from the steam drum to the water drum.

• They transfer cooler water back to the water drum.

• They connect the boiler to the ship’s propulsion system.

• They transport hot gases to the superheater.

Why are marine boilers constructed using carbon steel?

• Carbon steel absorbs heat more efficiently than other materials.

• It reduces the overall weight of the boiler.

• It can withstand high pressures and temperatures with minimal damage.

• It resists corrosion in high-moisture environments.

Which of the following is a critical advantage of three-element drum-level control systems?

• Improved performance under load variations

• Reduced complexity of boiler operations

• Elimination of the need for feed-forward control loops

• Lower cost compared to single-element systems

What is the key limitation of fire tube boilers for industrial applications?

• Inability to handle multiple fuel types

• Reduced heat transfer efficiency at high pressure

• Smaller steam generation capacity

• High maintenance requirements for extended use

What principle governs the operation of a marine boiler?

• Combustion of fuel generates heat for the engine.

• Steam is created by mixing hot gases and water.

• Thermal energy is captured from external sources.

• Heat energy converts water to steam within a sealed vessel.

In turbine-follow mode, how does the system manage load changes?

• By adjusting boiler water levels

• By directly controlling turbine steam flow

• By increasing fuel input to the boiler

• By using bypass systems to handle excess pressure

What role do "superheater tubes" play in a water tube boiler?

• • They generate steam by heating water.

• They carry superheated steam to ship systems.

• They protect other components from thermal damage.

• They return condensed water to the steam drum.