【摘 要】
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1概述止回阀广泛用于石油、化工和电力供暖锅炉等装置中,主要用于阻止管道中的介质逆向流动,保护设备安全运行。但是,普通的旋启式和升降式止回阀存在易粘卡,密封不严,难以维
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1概述止回阀广泛用于石油、化工和电力供暖锅炉等装置中,主要用于阻止管道中的介质逆向流动,保护设备安全运行。但是,普通的旋启式和升降式止回阀存在易粘卡,密封不严,难以维修等问题,阀门自行关闭时可能会产生严重的关阀水锤。由于水锤压力远超过系统工作压力,故可能危及系统安全。所以止回阀的设计除了满足流量的基本要求外,最重要的是流阻大小、是否有脱流或漩涡存在。新型球
1 Overview Check valves are widely used in petroleum, chemical and electric heating boilers and other devices, mainly used to prevent reverse flow of media in the pipeline to protect the safe operation of equipment. However, ordinary swing-type and lift check valves are easy to stick cards, lax sealing, difficult to repair and other issues, the valve may be closed on their own serious off valve water hammer. As the water hammer pressure far exceeds the system pressure, it may endanger the safety of the system. Therefore, the design of check valve in addition to meet the basic requirements of traffic, the most important thing is the size of flow resistance, whether there is shedding or vortex exists. New ball
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