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Denver by Bill Corey Pentair Water Training Institute So last month, we learned if we lower the pressure over 70°F (21ºC) water, it would flash or convert from a liquid to a vapor. Re- member we call it boiling, or in pump lan- guage “cavitation”. The conversion of a liquid to a vapor. We also asked the question: What does the 14.7 psi have to do with our cen- trifugal pump? If our pump is primed - meaning we have it filled with water - remember if you don’t have it filled with water and turn it on we call it a FAN be- cause all it does is move air around. Yes, even submersible pumps have to be primed. However, once filled with water - primed - when we turn the pump on, the impeller starts to spin and move the water from the inside or eye of the impeller to the outside or peripheral where it exits through the port of the impeller. When you look at the impeller, the vane moves with a curve from the eye to the port. Looking at the area between the vanes at the eye and comparing it to the area between the same vanes at the port, we can see where Bernoulli’s Law comes into play. Bernoulli stated that if the area is smaller, the water will have to move faster, and as the water moved faster the pressure would be lower. So the im- peller is designed to always have a lower pressure at the eye than at the peripheral. This of course is how the weight of the atmosphere helps move the water from its source to the impeller eye. Remember 14.7 psi x 2.31 FoH = 33.95 FoH (feet of head). So as mentioned last month, we can theo- retically lift - you are actually pushing the water from its source to the pump - water 34 feet. Of course, this is at sea level and does not take inherent losses into account. Most engineers will say 25 feet is the maximum lift for a centrifugal pump at sea level. It is the weight of the atmosphere that pushes the water up to the pump. We call it lift. The other really important thing to remember is this is all happening at sea level. As you go up in altitude you lose the ability to lift water. The reason is, you lose atmospheric pressure. You will lose about 1 psi for every 2000 feet for the first 8000 feet you go up. Denver is known as the Mile High City and a mile is 5280 feet. This means at 4000 feet you will have lost 2 psi; another 1000 feet and you lose ½ psi; the last 280 feet not quite but let’s call it .2 psi, which makes a total of 2.7 psi loss x 2.31 FoH = 6.24 feet. This means if I can lift water at sea level at 25 feet, in Denver I could use the same pump, but only lift it 19 feet of lift! Let’s talk about NPSH next month. Bill Bill Corey may be contacted via e-mail to michele@ worldwidedrillingresource.com %576 /2'%7)( %1( 63%5)6 3529-()( *25 );-67-1+ )48-30)17 ? 527%5< 7%&/)6 12: 352(8')( :-7, /%5+) 5-1+ +)%5 %1( 3-1-21 ))( !)3%-56 !27%5< 7%&/)6 = 8( 38036 = %.25 '20321)176 1-( 5-// "<67)06 1' 1-( 5-// $) %5) ()(-'%7)( 72 7,) :%7)5 :)// -1(8675< $ ,)67187 9) 1-( ,21) %; ::: )1-((5-// '20 21@7 *25+)7 5()5 <285 '23< 2* >#5%16*)5 2* #)',12/2+<? :5-77)1 &< 2,1 @ 632-5 2::2?? &1 2:?;: $5;:2 .C &607 ;=: =80/6? 3=;:?62= 0;9 288 .>;: ;=: =80/6? 3=;:?62= 0;9 288 +++ #! F "2B )>21 /6?> 3=;9 H ?; H F ( (##( " + )' + J+ "(J(#J ),J ,#)&J" +J')&$ )'J (' )' J (' J )" J (' F #A2= /6?> 6: >?;07 3;= #68 .> +.?2= +288 2;?52=9.8 C<8;=.?6;: ;:>?=@0?6;: 2?0 F +2 .8>; 0.==D $ /6?> 5.992=> .:1 5.992= /6?> F +2 0.: /@681 >?./686E2=> 6: .:D >6E2 .:1 .:D 0;::20?6;: F + J "J ) J ",J' - & ! &J#&J # #$ " & * &( #& -#"( #&J + J "J * " & ) J,#)&J& ! &J#& # J#$ " & F +2 9.72 >@/ .1.<?;=> B6?5 .:D 0;::20?6;: F %@607 (@=:.=;@:1 88 B;=7 6> 1;:2 6: 5;@>2 F 88 9.?2=6.8> .=2 6: >?;07 ,;@= B632 0.8821 '52 >.61 G ?I> # 3;= D;@ ?; /@D .88 ;3 D;@= /6?> .:1 1=6886:4 >@<<862> 3=;9 & 6? '2=A602 H 15 WorldWide Drilling Resource ® FEBRUARY 2016 WWDR ’ s April issue DEADLINES: Space Reservation: February 25 th Display & Classified Ad Copy: March 1 st