Pump Istallation; Pump Selection - Bertolini GIARDINAGGIO Serie Manual De Uso Y Mantenimiento

3. PUMP INSTALLATION
3.1

Pump selection

The pump should normally be chosen according to the flow rate (l/min or USGPM).
At the present time, there are no reference standards for determining the minimum flow
rate of the pumps installed on spraying machines. Reference is usually made to the
following calculation formulas:
1. Calculate the flow rate of spraying boom D:
D
Where:
indicates the flow rate of the spraying boom (given in l/min)
"D"
"LHa" indicates the volume of water (given in l/Ha) sprayed by the boom
indicates the speed (given in kph) with which the treatment is carried out
"V"
indicates the length of the boom or, in the case of mist blowers, the distance
"L"
between the rows (given in m)
conversion coefficient (fixed number)
600
2. Calculate the flow rate of pump Dp:
Dp
Where:
"Dp" indicates the flow rate of the pump (given in l/min)
indicates the flow rate of the spraying boom (given in l/min)
"D"
indicates a flow rate increase percentage (normally 10% of the boom flow
"Dr"
rate) so as to allow the regulating valve to maintain the pressure correctly
"Da" indicates a flow rate increase percentage (normally 5% of the tank capacity)
so as to allow the stirring system to function correctly.
Example:
Given an area treated at a speed of 7 km/h with a 12 m spraying boom that distributes 200
l per hectare and using a 700 l capacity tank, determine the pump minimum flow rate:
1. First calculate the flow rate of spraying boom D:
 
LHa V L
 
D
600
2. Lastly, calculate the minimum flow rate of pump Dp:
  
Dp D Dr Da
The flow rate of the pump must not be less than 65.8 l/min.
Another method to calculate the pump flow rate is to refer to the characteristics of the
nozzles.
 
LHa V L

600
  
D Dr Da
 
200 7 12 16800
 
600 600
   
28 ( 28 10 %) ( 700
28 L / min
    
5 %) 28 2 8 , 35 65 8 , L / min
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