Unigas HTP2000 Installation Manual page 11

Checking the proper gas train size
To check the proper gas train size, it is necessary to the available
gas pressure value upstream the burner's gas valve. Then subtract
the backpressure. The result is called pgas. Draw a vertical line
matching the furnace input value (600kW, in the example), quoted
on the x-axis, as far as intercepitng the network pressure curve,
according to the installed gas train (DN65, in the example). From the
interception point, draw an horizontal line as far as matching, on the
y-axis, the value of pressure necessary to get the requested furnace
input. This value must be lower or equal to the pgas value, calcula-
ted before.
Pressure in the Network / gas flow rate curves(natural gas)
Caution: the gas rate value is quoted on the x-axis, the related network pressure is quoted on the y-axis
(pressure value in the combustion chamber is not included). To know the minimum pressure at the gas train
inlet, necessary to get the requested gas rate, add the pressure value in the combustion chamber to the value
read on the y-axis.
25
20
15
10
5
0
100 200 300
11
PART I: SPECIFICATIONS
Rp 2" (50)
DN65 DN65
400 500 600 700 800
Power kW
Potenza / Output (kW)
kW
900