A control valve for limiting pressure down-surges during hydrant operations

配水系统的设计要求系统中任何一点的压力保持在最低水平以上，以确保有足够的流量来满足预期的需求。最小压力标准通常是为配水系统的安全运行设定的，其目标是允许在运行期间提供所需的流量，以防止直接污染。然而，在由消火栓快速打开等事件引起的瞬态事件中，经常违反最小压力准则。一种可以快速连接到消火栓上的便携式控制装置，即使消防人员尽可能快地打开消火栓，也可以将低瞬时压力限制在所需的水平。如何设计并应用于暂态保护是本提案的核心。通过使用该装置，可以在消火栓或阀门操作期间更好地控制供应系统和其他液体系统中的压力，从而使水务公司和保险公司可以降低他们所需的最低压力标准。通过减少管道破裂频率、泄漏率、系统能源使用和水需求，减少了过量压力，从而大大节省了公用事业公司的运营成本。

The design of water distribution systems requires that pressures at any point in the system be maintained above a minimum level to ensure adequate flows for satisfying expected demands. A minimum pressure criterion is typically set for the safe operation of water distribution systems with the goal of allowing the supply of the required flows to prevent direct contamination during operations. However, the minimum pressure criterion is often violated during transient events resulting from events like rapid fire hydrant openings. A portable control device which can be quickly attached to a hydrant is conceived here to limit low transient pressures to desired levels even if fire crews open the hydrant as fast as they would. How the novel device can be designed and applied for transient protection is the heart of this proposal. With the use of this device, pressures in supply systems and other liquid systems can be better controlled during hydrant or valve operations such that water utilities and insurance companies can reduce the minimum pressure criterion that they require. The resulting reduction of excess pressures can result in large operational savings to utilities through reduced pipe break frequencies, leakage rates, system energy use, and water demands.