Formulas, Laws, Conversions and Related Data

H = hd - hs

 hd = hsd + hpd + hfd hs = hss + hps = hfs where: hd = total discharge head hs = total suction head hsd = discharge static head hss = suction static head hpd = discharge surface pressure hps = suction surface pressure hfd = discharge friction head hfs = suction friction head

### AVAILABLE NPSH

Available NPSH is "the difference between the total suction head and the vapor pressure of the liquid, in feet of liquid, at the suction flange."

hsv = hsa - hypa

where:

hsv = available net position suction head, in feet of liquid

hsa = total suction head, in feet of liquid, absolute

hypa = vapor pressure of liquid at suction nozzle, in feet of liquid, absolute

### PRESSURE Conversion:

Head (ft.) = psi x 2.31 / sp. gr.

PSI = head (ft.) x sp. gr. / 2.31

Lbs./sq. in. = In. of Mercury x .491
Lbs./sq. in. = Atmospheres x 14.7

mm hg. = Atmospheres x 760

### VISCOSITY

Centistokes x 4.64 = SSU(approx.)

Centipoise Sp. Gr. = Centistokes

### FLOW

Gallons per minute (GPM) x 3.785 = Leters per minute

### TEMPERATURE Conversion:

°C = 5/9 (°F - 32)

°F = 9/5°C + 32

### SPECIFIC GRAVITY

sp. gr. = weight of liquid
sp. gr. = weight of water

weight of water = 62.4 Lb./cu.
weight of water = 8.3 Lb./gal.

### POWER

BHP = GPM x TDH x sp. gr.
BHP = 3960 x Eff.

BHP = GPM x PSI
BHP = 1715 x Eff.

KW = 0.746 x H.P.

Torque = (Ft. Lb.) = HP x 5260
Torque = (Ft. Lb.) = RPM

HP = E(volts) x I(Amps) x Eff. X P.F. x 1.732
HP = E(volts) x I(Amps)746

I(amps) = HP x 746
I(amps) = E(volts) x Eff. X P.F. x 1.732

### O-RING TEMPERATURE LIMITATIONS

Material[Code]
Temperature Limits

Modified Polytetrafluorethylene [TM]
Low: -100 °F (-73 °C) High: 300 °F (149 °C)

Viton [VA]
Low: -20 °F (-29 °C) High: 400 °F (204 °C)

Perfluoroelastomer (Kalrez) [KAL]
Low: -36 °F(-38 °C) High: 550 °F (287 °C)