Manual for the Design of Pipe Systems and Pumps - GEA ...

7.5 Result
7. In diagram 4 (Fig. 32), first the viscosity factor required for calculat ing the capacity is
determined by draw ing a vertical line upwards from the point of intersection of viscosity
with the characteristic curve
8. and by reading the corres ponding viscosity factor f on the scale of the abscissa (2.8)
From the table in Diagram 4 (Fig. 32) find out factor S
according to the selected gasket.
The required motor power is calculated
as follows:
The required drive torque can now
be calculated as follows:
9. From Diagram 5 (Fig. 32) the required pressure at the suction port (NSPH req) can be read
(intersection pump speed / viscosity).
The pressure prevailing at the suction port (NPSH avl) should always be 0.1 bar
higher than the required pres sure in order to prevent cavitation.
erforderlicher Druck am Saugstutzen (bar abs.)
net inlet pressure required - N.I.P.R. - (bar absolute)
1.000.000
Viskosität (cp) / Viscosity (cp)
100.000
10.000
The result of the pump design is a VPSH 54 pump with a 3.0 kW motor and a pump
speed of 750 rpm.
2,0
1,8
1,6
1,4
1,2
1,0
0,8
0,6
0,4
0,27
0,2
0
1.000
100
10
Fig. 32
atmospheric
pressure
100 200 300 400 500 600 700 800
715
900 1000 1100 1200 1300 1400 1500
2,8
Pumpendrehzahl (U/min.) / Pump speed (rpm)
Viskositätsfaktor f / Viscosity factor f
2 4 6 8 10 12 14 16 18 20 22 24 26
8
7
100.000 cp
30.000 cp
Diagramm 4
10.000 cp
9
3.000 cp
Kraftbedarf / Power Absorbed
Dichtung Typ Code Faktor S
Seal Type Code Factor S
Einfach / Single C/SS 8 1
Einfach / Single C/SIC 3 1
Einfach / Single SIC/SIC 2 2
Doppelt / Double C/SIC 4 2
Doppelt / Double SIC/SIC 1 3
p
P (W) = ( + f + S x 0.455 x N
0.61 )
P (W) x 9.56
M (Nm) =
N
p = Differenzdruck / Differential pressure (bar)
N = Drehzahl (U/min) / Speed in rpm
f = Viskositätsfaktor aus dem Diagramm /
Viscosity factor from graph
S = Dichtung (siehe Tabelle) /
Seal factor from table
P = Leistung / Power (W)
M = Drehmoment / Torque (Nm)
35
GEA Tuchenhagen
max. Drehzahl / max. speed
Diagramm 5
1.000 cp
300 cp
100 cp
10 cp
1 cp
NIPR
atmosphärischer
Druck
Technische Daten / Application Data
Max. Wellendrehmoment /
Max. input shaft torque (Nm) 150
Max. radiale Wellenbelastung /
Max. shaft radial load (N) 2250
Max. Partikelgröße (weich) /
Max. soft particle dia. (mm) 15
Verdrängung / Displacement (cc/rev) 455
Verdrängung /
Displacement (litres/100revs) 45.5
Physikalische Daten / Physical Data
Gewicht der Pumpe ohne Antrieb /
Bareshaft pump weight (kg) 35
Ölvolumen / Oil capacity (cc) 1100
Rückhaltevolumen /
Hold up volume (cc) 820
(horizontale Anschlüsse) /
(horizontal ports)
Anzugsmomente / Tightening Torques (Nm)
Enddeckelbolzen / End cover bolts 20
Rotorschrauben / Rotor retainer screws 55
Rotorgehäuseschrauben /
Rotor case screws 20
Getriebedeckelschrauben /
Gear cover screws 15
Zahnradmuttern / Gear nuts 100
Rotorzugstangenschrauben VPSU /
Rotor tie rod nuts 40
Rotortoleranzen / Rotor Clearances (mm)
Vorne, Rotor zum Deckel /
Front, rotor to end cover 0.15
Radial, Rotor zum Rotorgehäuse /
Radial, rotor to rotor case 0.25
Rotor zu Rotor / Mesh, lobe to lobe - min 0.20
p
P (W) = 0.61 + f + S x 0.265 x N
( )
5
P (W) = +2,8 + 1 x 0.265 x 715
0.61
( )
= 2.27 kW
P (W) x 9.56
M (Nm) =
N
M (Nm) = 2270 x 9.56 = 30.35 Nm
715