Well in Standard Donkey Pump units the answer would be Sqrt(13).
However, in east-ethiopian Donkey Pumps, the answer would in fact be, Margret Thatcher.
A donkey pump is a supplementary pump which is brought on line if needed.
Negative Suction Head means the pump is drawing liquid up from below its centerline. The distance between the centerline of the pump and the surface of the fluid is measured in head feet, this can be negative (below the pump) or positive (above the pump).
Two of the most common causes of pump cavitation are air in the pump or the fluid being pumped is too hot. Water at 180 degrees will cause the pump to cavitate (steam bubbles form in the eye of the pump on the suction side of the impeller) because of the drop in pressure created on the suction of the pump. This can be corrected by either pumping cooler water, or by raising the net suction head of the pump. Air in the pump can be corrected by venting the pump.
The pump discharge reducer doesn't matter if it's concentric or eccentric. It's the pump SUCTION that needs to be an eccentric reducer that is always flat on top (F.O.T.) The eccentric reducer on the pump suction reduces pump cavatation (pump catching air).
Suction lift is only negative. Suction head is positive or negative.Suction head is the distance between the surface of the liquid being pumped and the centerline of the pump. It can be positive or negative, and it can be affected by pressure or vacuum on the surface of the fluid. A negative suction head is also called suction lift.Example 1: A D/A under 15 psig is set 20 feet above the feed pump the effective suction head is 54 feet. (15 psig is equivalent to 34 feet of water).Example 2: A Condenser hotwell under 28 inches of vacuum (Hg) is set 16 feet above the suction of a propeller pump. The effective suction head (lift) is -15 feet.* (28"Hg = - 31 feet of water)Example 3: A sump pump is set 4 feet below the surface of the well. The effective suction head is 4 feet.*Note: Suction lift is only effective to a maximum of 21 feet, and 15 feet for hot water depending on temperature and pump slip.
this is overhang centrifugal pump . the suction drum level , suction strainer and suction pipings were all checked and found OK
A donkey pump is a supplementary pump which is brought on line if needed.
what is th different between end suction pump and singl stage pump and multistage pump
A single suction pump having its suction nozzle on the opposite side of the casing from the stuffing box and having the face of the suction nozzle perpendicular to the longitudinal axis of the shaft
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Condensate pump suction pressure below 4 feet of the condenser is almost equal to condenser pressure (760mm of Hg). If the pump equiped under the deep pit , suction pressure is vary.
It is common practice to specify the pump suction line one size larger than the pump discharge line in order to increase the Net Positive Suction Head available (NPSHA) to the pump. A smaller suction line the same pipe size as the discharge line would result in more pressure drop in the suction line and reduce the amount of head available to the suction side of the pump. This in turn would result in an operating point closer to cavitation of the pump.
To compensate high suction volume during startup of he pump. the reducer area below the pipeline at the suction stores excess volume of fluid.
what is the meaning of double suction
Negative Suction Head means the pump is drawing liquid up from below its centerline. The distance between the centerline of the pump and the surface of the fluid is measured in head feet, this can be negative (below the pump) or positive (above the pump).
It will damage the pump.
if we use concentric reducer at suction of pipe ,due to high turbulence flow of fluid ,some vapour pressure generate which generate bad effects on impeller of pump ,which decrease pump efficiency , so to avoid this problem the eccentric reducer's use in pump suction