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' .... ................ Conversion Tables
16.2.13 Suction specific speed
RPM x QO.5
Nss =
NPSHRO.75
where RPM = Pump Rotational Speed
Q = Flow at BEP
NPSHR = NPSH required at BEP
16.2.14 Calculation of grease service life
T = K [14.0 x 106
nx~/d -4d
where T = Grease service life (hours)
K = Factor for bearing type (10 for ball brgs.)
n = Pump rotational speed
d = Bearing Bore (mm)
16.2.15 L-10 Bearing life calculation
[cl~
L-10 = A23 x 1,000,000
60xn
where a23 = Lubrication effectiveness factor
C = Basic dynamic load rating
P = Equivalent dynamic bearing load
P = Exponent of the life equation (3 for ball brgs.)
P = Pump rotational speed
16.2.16 Slurry specific gravity
SL
S m
1+ Cw I SL -1]
~s
where S m ~- Specific Gravity of the Slurry
SL = Specific Gravity of the Liquid
S s - Specific Gravity of the Solids
Cw = Concentration of solids by weight
(30% is used as 0.30)
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