Weir SPM TWS600S - Useful Pump Data Formulas

Document P/N:
2P121260
Release Date: 02/27/2017
Revision: E
7 of 41
Useful Pump Data Formulas:
Definition of Symbols Used:
A - Area (sq. in.)
BHP - Brake horsepower
BPM - Barrels per minute (U.S.)
FV - Flow velocity (feet per second)
GPM - Gallons per minute (U.S.)
GPR - Gallons per revolution (U.S.)
HHP - Hydraulic horsepower
ID - Inside diameter (inches)
ME - Mechanical efficiency
NC - Number of cylinders (per pump)
PD - Plunger diameter (inches)
PSI - Pounds Per Square Inch
RL - Rod load (pounds)
RPM - Crankshaft revolutions per minute
SL - Stroke length (inches)
T - Torque (foot pounds)
Pump Data Formulas:
 To calculate the HHP output when the volume and pressure are known:
GPM x PSI = HHP
1714
 To calculate the BHP input required when the volume, pressure, and mechanical efficiency are known:
GPM x PSI = BHP
(1714 x ME)
 To calculate the maximum possible pressure when the BHP, flow, and ME are known:
BHP x (1714 x ME) = PSI
GPM
 To calculate the maximum possible flow when the BHP, PSI, and ME are known:
BHP x (1714 x ME) = GPM
PSI
 To calculate rod load when the plunger diameter and pressure are known:
PD x PD x .7854 x PSI = RL
 To calculate the maximum possible pressure at a given rod load when the RL rating and plunger
diameter are known:
RL = PSI
PD x PD x .7854
SECTION I: GENERAL INFORMATION