Pump NPSH(a), Suction and Delivery Lines Head Loss Calculation  
S.NO Description Values UOM  
1 Pump Capacity   M3/hr  
2 Pump Suction line dia  mm  
3 Number of   valves in Suction line (b/f)  no.s  
4 Suction length including bends  mtrs  
5 Number of 90o bends in Suction  no.s  
6 No. of "T" bends in Suction  no.s  
7 Delivery line size  mm  
8
Author:
including horizontal and vertical length
Total delivery line length (including horizontal and vertical length)
mtrs  
9 Elevation from pump shaft to delivery end point  (Vertical height only) mtrs  
10 Nunber of Right angle valves in delivery line no.s  
11 Number of  B/F valves in delivery line no.s  
12 Number of double beet valves in delivery line no.s  
13 Number of 90o bends in delivery line no.s  
14 Number of 45o bends in delivery line no.s  
15 Number of "T" bends in delivery line no.s  
16 Liquid Temperature in oC oC  
17 Liquid Brix in % (Solids percent) 15 %  
18
Author:
if negative head than enter negative value
Average maintained Liquid level in suction tank from the pump shaft (if negative head than enter negative value)
Author:
if negative head than enter negative value
mtrs  
19
Author:
atmospheric pressure;
taking that as 770 mm of mercury:
Suction Tank condition 
Author:
Receiving mound having vent or open or having equalizing line than atmospheric pressure taking as 770 mm of mercury:
mm of Hg  
20 Liquid Density  kg/m3  
21
Author:
peter rein 745
The Dynamic viscosity of liquid 
 Centi poise  
Results  
1 Water Vapour pressure at given liquid temperature MWC  
2 Flow Quantity M3/sec  
3 The kinematic viscosity of liquid (η) in  m2/sec  
4 Resistance coefficient for 90obend in suction line    
5 Resistance coefficient for "T" in suction line    
6 Resistance coefficient for b/f valve in suction line    
7 Resistance coefficient for 90obend in delivery line    
8 Resistance coefficient for 45obend in delivery line    
9 Resistance coefficient for "T" in delivery line    
10 Resistance coefficient for b/f valve in delivery line    
11 Resistance coefficient for right angle valve in delivery line
12 Resistance coefficient for Double beet valve in delivery    
  NPSH(a) CALCULATION      
A Pressure at the tank mwc  
B Vapour tension mwc  
C Suction Head mwc  
D Loss of Head in Suction line      
  Velocity of meterial in suction line  (U ) in m/sec m/sec  
  Reynolds number R= UD/η    
 
Author:
Hugot- 1120
Resistance coefficient for suction pipe (λ )
     
  λ = 0.0032+(0.221/R0.237)    
  λ = 0.01(A/D)0.314    if take A= 2.5    
  λ = 0.01(A/D)0.314    if take A= 5    
 
Author:
Here λ = 0.0032+(0.221/R0.237) consider R value having below 100000 and λ = 0.01(2.5 /D)0.314 consider R value having 100000 to 1000000 and λ = 0.01(2.5 /D)0.314 consider R value having above 1000000
λ value according to Reynolds number
   
a
Author:
λ x U2 / (Dia x 2g)
Head loss due to Pipe length
mwc  
b Head loss due to 90obend in suction mwc  
c Head loss due to "T" in suction mwc  
d Head loss due to b/f valve in suction mwc  
  Loss of Head in Suction line (a+b+c+d) mwc  
  NPSH available (A -B+C-D) mwc  
  Loss of Head in Delivery line      
  Velocity of meterial in delivery line  (U ) m/sec  
  Reynolds number R= UD/η    
  Resistance coefficient for delivery pipe  (λ )      
  λ = 0.0032+(0.221/R0.237)    
  λ = 0.01(A/D)0.314    if take A= 2.5 for new cost iron or steel,     
  λ = 0.01(A/D)0.314    if take A= 5 for old rusted lines    
 
Author:
Here λ = 0.0032+(0.221/R0.237) consider R value having below 100000 and λ = 0.01(2.5 /D)0.314 consider R value having 100000 to 1000000 and λ = 0.01(2.5 /D)0.314 consider R value having above 1000000
λ value accoding to Reynolds number
   
e Head loss due to delivery Pipe line length mwc  
f
Author:
K x U2 / 2g
Head loss due to 90obend in delivery line 
mwc  
g Head loss due to 45obend in delivery line mwc  
h Head loss due to right angle valve in delivery line mwc  
i Head loss Double beet valve in delivery line mwc  
j Head loss due to "T" in delivery line mwc  
k Head loss due to b/f valve in delivery line mwc  
         
E Loss of head due pipe length and fittings in delivery line (e+f+g+h+i+j+k) mwc  
  Total head loss in delivery line (10 + E) mwc  
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