water hammer


Definition of water hammer

: a concussion or sound of concussion of moving water against the sides of a containing pipe or vessel (such as a steam pipe)

Examples of water hammer in a Sentence

Recent Examples on the Web Manufacturers now make inexpensive, easy-to-install water hammer arrestors where these appliances connect to the water system. Washington Post, "How to stop loud knocking in the water pipes," 21 Sep. 2020 Because it is being pumped to a higher point, the flow soon reverses, closing the delivery valve, and creating another water hammer that moves back up the inlet pipe, sucking the waste valve downwards into the open position again. Nithyanand Rao, Quartz India, "An IISc scientist joins hands with remote Indian tribals to gently harness a river," 23 Oct. 2019 This closure of the valve causes pressure inside the pump to build up—the water hammer effect—and exceed that due to the water pressing down from outside on the delivery valve, causing that valve to open and let out some of the water. Nithyanand Rao, Quartz India, "An IISc scientist joins hands with remote Indian tribals to gently harness a river," 23 Oct. 2019 The water hammer effect causes the pipe to displace from its equilibrium position. Sarah Harvey, Curbed, "The marble upstairs," 17 June 2019 Aside from leak repairs, the agency is banking on two new water hammers to iron out future pressure drops and avoid boil advisories. Beau Evans, NOLA.com, "Running faucets or leaks: What most strained New Orleans during the freeze?," 6 Jan. 2018 That may have triggered the kind of rapid valve closure that brings about a water hammer, U-M engineering professor emeritus E. Benjamin Wylie said. Keith Matheny, Detroit Free Press, "Expert on 'water hammers' says it may be behind Oakland water pipeline failure," 25 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'water hammer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of water hammer

1765, in the meaning defined above

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Time Traveler for water hammer

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The first known use of water hammer was in 1765

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Cite this Entry

“Water hammer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20hammer. Accessed 28 Jan. 2021.

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