Riello GI/EMME 1400, Руководство пользователя

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25 20162463 GB
Installation
The values shown in Tab. L refer to:
–
Natural gas G 20 NCV 9.45 kWh/Sm
3
(8.2 Mcal/Sm
3
)
– Natural gas G 25 NCV 8.13 kWh/Sm
3
(7.0 Mcal/Sm
3
)
Column 1
Combustion head pressure drop.
Gas pressure measured at test point 2)(Fig. 26), with:
•
combustion chamber at 0 mbar;
• burner working at maximum modulating output;
• combustion head adjusted as in page 19.
Column 2
Pressure drop at gas butterfly valve 1)(Fig. 26) with maximum
opening: 90°.
To calculate the approximate output at which the burner
operates:
–
subtract the combustion chamber pressure from the gas
pressure measured at test point 2) (Fig. 26).
– Find in Tab. L related to the burner concerned, the pressure
value closest to the result of the subtraction.
– Read the corresponding output on the left.
Example G/M 3000 with natural gas G20:
Operation at maximum modulating output
A pressure of 27.9 mbar, column 1, corresponds in Tab. L to an
output of 2983 kW.
This value serves as a rough guide; the effective output must be
measured at the gas meter.
To calculate the required gas pressure at test point 2) (Fig. 26),
set the maximum modulating output required from the burner
operation:
–
find the nearest output value in the table Tab. L for the burner
in question.
– Read, on the right (column 1), the pressure at the test point
2)(Fig. 26).
– Add this value to the estimated pressure in combustion
chamber.
Example G/M 3000 with natural gas G20:
Operation at maximum modulating output
pressure required at test point 2)(Fig. 26).
+
Gas pressure at test point 2)(Fig. 26) = 32.9 mbar
Pressure in combustion chamber = 5 mbar
32.9 - 5 = 27.9 mbar
Gas pressure at an output of 8000 kW = 27.9 mbar
Pressure in combustion chamber = 5 mbar
27.9 + 5 = 32.9 mbar
2
1
Fig. 26
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