What is the primary advantage of a piston valve over a traditional D-slide valve____________________?
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Answer: C. both wear and power absorbed are low
Explanation
Piston valves utilize balanced cylindrical plugs that eliminate the high friction forces experienced by flat slide valves. This balanced pressure design significantly reduces both mechanical wear on sealing surfaces and overall power absorption. Engineers favor piston valves in steam and hydraulic applications due to their high operational efficiency and longevity. Traditional D-slide valves suffer from high steam pressure pressing them against flat valve seats, increasing friction. Piston valves surround the sliding plugs with steam ports, equalizing radial forces and minimizing frictional drag. Materials selection and precise machining ensure tight clearances that prevent leakage without excessive contact pressure.
Lower wear alone ignores the significant reduction in power absorption achieved by balancing the steam pressures. Reduced power absorption without mentioning wear provides an incomplete picture of the overall mechanical benefits. High sealing pressure often increases friction in traditional valves, whereas piston valves achieve tightness via close clearances.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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