Aux 1 Unit 2 Q2

Correct Answer: B) Butterfly valve

Explanation: Butterfly valves are commonly used at the discharge of cooling water circulating pumps because they provide a good balance between ease of operation, quick opening/closing, and relatively low cost. They are suitable for applications where a large volume of fluid must be controlled with minimal pressure drop.

Correct Answer: B) To ensure continuous fuel supply to the engine

Explanation: The primary reason for the operation of the fuel service tank outlet valve is to ensure that the engine receives a continuous and uninterrupted supply of fuel. This is critical for the reliable operation of the engine, especially in demanding marine environments.

Correct Answer: C) It has an automatic shut-off feature in case of low fuel level

Explanation: Many fuel service tank outlet valves are equipped with an automatic shut-off feature that activates if the fuel level drops too low, preventing air from entering the fuel system and potentially causing engine problems.

Correct Answer: B) The engine may be starved of fuel, leading to a shutdown

Explanation: If the fuel service tank outlet valve fails to operate correctly, the engine may not receive enough fuel, which can lead to a loss of power or a complete shutdown, posing serious risks in marine operations.

Correct Answer: C) Gate valve

Explanation: Gate valves are most appropriate for use as isolating valves in a fire main system because they provide a straight-line flow with minimal resistance when fully open and can be completely closed to provide a tight seal. This is essential for fully isolating sections of the fire main without allowing any leakage.

Correct Answer: B) It operates manually or automatically to allow fuel to flow from the service tank to the engine

Explanation: The fuel service tank outlet valve is designed to control the flow of fuel from the service tank to the engine. It can be operated manually or automatically, depending on the system design, to ensure that the engine receives a steady supply of fuel as needed.

Correct Answer: C) It can be fully opened or closed, providing a reliable seal

Explanation: The gate valve is designed to either fully open or fully close, ensuring that sections of the fire main can be completely isolated when necessary. This reliable sealing capability is crucial in maintaining the integrity of the fire-fighting system.

Correct Answer: B) It is compact and operates quickly

Explanation: The butterfly valve is favored for its quick operation and compact design, which is ideal for controlling the flow of cooling water in systems where space and response time are critical factors.