Essay About Pump Centre Line And M3

Calculating Npsh Of Pump
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NPSHA in the system is calculated as :
NPSHA = Terminal Pressure in the vessel (in guage)
(+) Static Head of fluid above pump centre line (see note).
(+) Atmospheric Pressure
(-) Vapour Pressure of liquid at pumping temperature
(-) Friction loss in suction piping up to pump centre line consisting of the following :
Ð* Entrance and exit losses
Ð* Loss in suction strainer
Ð* Loss in control valves, instruments, exchangers etc. if any
Ð* Line losses
Note : a) The height of liquid in the vessel should be taken to be at the vessel bottom tangent line.
b) Height of the pump centreline is calculated as follows :
HPC = HPB + F where
HPC = height of pump centreline above finished floor level
HPB = height of pump centreline above pump baseplate
F = height of pump foundation above finished floor level
HPB is estimated from the following table based on typical vendor information :
Pump Flow Rate Height of Pump Centreline
(m3/hr) above Base Plate HPB (mm)
upto 200 450
200 – 300 650
300 Ð- 400 750
The height of foundation F is typically taken at 300 mm.
Calculate NPSHA carefully considering all Conditions i.e. start-up, original fill of lines, winter operation,
all control valve pressure drops, summer operation, piping conditions, exit and entrance losses. Provide
NPSHA