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Harper International, Article_6273, Prevent Surge Problems

Harper International: The Strategic Choice – Getting a Crystal Ball to Prevent Surge Problems.

Sure, it’s better to address a problem before it’s blossomed into a full-blown crisis, but some problems – like water system failure – are difficult to pinpoint until they happen. Because protection of water flow is the primary objective of a water system, that knowledge is critical, to say the least. Well, finally a crystal ball is available to prevent surge problems!

A primary potential culprit of system failure is brief (transient) low or negative pressures (surges) that can crush or burst pipes and valves, and allow contaminated water to enter the system. Pump trip or failure, flushing, hydrant use, main breaks, fast closing or opening valves, air valve or check valve slam, sudden system demand changes, and oscillating control valves can all cause transient low or negative pressure within a system, as can many the normal operational activities.

The perfect crystal ball would give you critical information on system performance, and where pressure drop spots might occur. And we are excited about the future-seeing capabilities of Cla-Val’s SurgeView software.

With the SurgeView software it is possible, during the system design process, to optimize the selection of appropriate surge and/or air valves to determine which will be the most efficient and economical. For existing installations, the software can also help to determine safe valve operating times or which control functions should be added to solve or prevent surge problems.

The American Water Works Association e-Journal has recently published a relevant study on surge problems. It is one of the first systematic, long-term studies to monitor real distribution systems (“Occurrence of Transient Low and Negative Pressures in Distribution Systems,” Gullick, LeChavallier, Svindland & Friedman). The study documents negative pressures in a variety of distribution systems and how contaminated water can enter the distributionsystem from external environments. The study’s results confirm the importance of planning for new systems and accurate diagnosis of existing systems to eliminate their susceptibility to low and negative pressures. SurgeView makes that planning process scientific, rather than anecdotal.

How does the SurgeView system work? It simulates the entire pipeline and the dynamic conditions that result during a surge event. A graph of pressures over time is superimposed on the pipeline profile during the analysis with maximum and minimum pressures shown along the pipe. An animation is displayed showing surge waves as they travel along the pipe. The designing engineer, using either Microsoft PowerPoint or Windows Media, can also view these animations. The graphics below illustrate the software’s capabilities, and you can watch an actual animated PowerPoint presentation of the software by clicking on this link: View software here. It’s fascinating to watch.

SurgeView-1

SurgeView-2


To find out more, contact a Harper representative.
Harper Haines Fluid Control, Inc.
125 Old Gate Lane, Milford, CT 06460
Telephone: 203.693.3740 * Fax: 203.547.6092
YOU CALL, WE ROLL.