Pipelines with diameters exceeding 2″ typically employ which type of valve______________?
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Answer: C. Gate valve
Explanation
Gate valves are preferred for isolation in larger pipelines above two inches because they offer low flow resistance. When fully open a gate valve provides an unobstructed flow path matching the pipe diameter. This design minimizes pressure drop and turbulence in large diameter fluid transport systems. Gate valves operate by lifting a rectangular or circular gate out of the fluid path. They are primarily designed for on-off isolation rather than precise flow throttling control. Larger industrial piping networks require low head loss components to maintain pumping efficiency.
Water distribution networks and petroleum pipelines utilize gate valves for sectional isolation. Industrial facility piping systems rely on gate valves for dependable mainline shutoff capabilities. Proper valve selection prevents excessive energy consumption caused by flow restrictions. Globe valves create significant flow resistance and pressure drop making them less ideal for large mains. Plug-cocks are typically restricted to smaller diameter instrumentation or specific fluid lines. Check valves serve to prevent backflow rather than providing manual pipeline isolation control.
- Subject
- Engineering
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- Chemical Engineering
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