Срабатывает при превышении дифференциального давления, то есть расхода, запирает проход. Нормируется давление отключения, включения и утечка в запертом состоянии
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Fluid flow fuse
Document Type and Number:
United States Patent 5722454

Abstract:
A fluid flow device has a body which includes an inlet and an outlet with a valve seat therebetween. A valve stem having a valve member thereon is mounted in the body, and the valve member is operably connected to a diaphragm which separates a region within the body into a pair of separate pressure chambers. A fluid passage is formed in the body communicating one pressure chamber with upstream pressure in the inlet, while the other pressure chamber communicates with downstream pressure in the outlet. A pressure differential between the chambers will normally hold the valve member in an open position against the action of a biasing means, until the pressure differential reaches a predetermined amount, whereby the valve member is slowly closed until fluid flow through the device is stopped. The valve seat and valve member do not form a perfectly tight seal so as to allow some leakage thereby allowing restricted fluid flow into the downstream side of the device and any system connected thereto, to prevent the system from being emptied.


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Note added at 36 мин (2009-04-01 06:36:06 GMT)
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Нужен, например, для прекращения подачи топлива при разрыве топливопровода, да хотьчегопровода.