Why is a feed check valve installed in a boiler system ______________________?
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Answer: D. allow high pressure feed water to flow to drum and not allow reverse flow to take place
Explanation
A feed check valve functions as a non-return valve installed on the feed water line entering the boiler drum. It permits high-pressure feed water pumped from external sources to open the valve and enter the pressure vessel. If the feed pump stops or feed line pressure drops, the internal pressure slams the valve shut to prevent dangerous backflow. Boiler safety systems require positive-sealing check valves to isolate pressure vessels from external water supply piping failures. Feed check valves often combine a shut-off valve with an integral check valve mechanism for operational convenience. Continuous high-pressure operation demands rugged valve body construction using corrosion-resistant alloy steels and bronze.
Regulating flow is typically handled by separate feed water control valves rather than the safety-oriented feed check valve. Checking water level is performed by sight glasses and electronic level transmitters rather than mechanical check valves. Recirculating unwanted feed water is managed by bypass piping networks and relief valves rather than the main feed check valve.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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