I wonder if you could help me with this we tested a fire pump last week using mini hose monsters. The hose monsters were at an elevation 46’ higher than the pump outlet.
Are there any calcs that I need to do to get an accurate test? In elevation this is a 20 psi loss plus 130’ of piping to reach the test header (one size larger than required) 8” for a 1000 gpm pump. Any help would be appreciated. Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe
4 Comments
Dave Sornsin
9/19/2019 11:55:21 am
Were you able to flow 1000gpm and (ideally) 1500gpm from the hose monsters?
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pjd
9/19/2019 09:39:56 pm
Pressure losses on the test header path don't calculate into your pitot readings. Those readings are experimental data used to determine how much water is flowing...at that point. The sum of your head loss and friction loss should be added to your discharge gauge pressure when you are flowing at rated flow and at 150% rated flow. That's assuming you're able to get to 150%. If the pump is operating as designed, when flowing the rated flow through the play pipes, the discharge gauge will read lower than the rated pressure. That difference should be roughly in line with the sum of your losses along the test header path at that flow rate. If you suspect degraded performance I would compare the theoretic Hazen Williams difference with the experimental difference.
Reply
ioan rincu
9/20/2019 11:18:56 am
You don't need that.
Reply
Bobby
9/20/2019 11:50:13 am
My opinion:
Reply
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