5
GAS PRESSURE
The adjacent tables show minimum pressure
losses along the gas supply line depending on
the maximum burner output operation.
Column 1
Pressure loss at combustion head.
Pressure of the gas at the socket 1)(B), with
combustion chamber at 0 mbar.
Column 2
Pressure loss at gas butterfly valve 2)(B) with
maximum opening: 90°.
Column 3
Pressure loss of gas train 3)(B) includes: adjust-
ment valve VR, safety valve VS (both fully
open), pressure governor R, filter F.
The values shown in the various tables refer to:
natural gas G 20 PCI 9.45 kWh/Sm
3
(8.2 Mcal/Sm
3
)
With:
natural gas G 25 PCI 8.13 kWh/Sm
3
(7.0 Mcal/Sm
3
)
multiply the values of the table:
- columns 1-2: by 1.5;
- column 3: by 1.35.
Calculate the approximate maximum output of
the burner in this way:
- subtract the combustion chamber pressure
from the gas pressure measured at test
point 1)(B).
- find, in the table relating to the burner con-
cerned, the pressure value closest to the
result of the subtraction.
- read the corresponding output on the left.
Example - RS 35/M BLU:
• Maximum output operation
• Natural gas G 20 PCI 9.45 kWh/Sm
3
• Gas pressure at test point 1)(B)
=8.5 mbar
• Pressure in combustion chamber
= 2 mbar
8.5 - 2 =6.5 mbar
A maximum output of 350 kW shown in Table
RS 35/M corresponds to 6.5 mbar pressure,
column 1.
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 1)(B), set the maximum output required
from the burner operation:
- find the nearest output value in the table for
the burner in question.
- read, on the right (column 1) the socket pres-
sure 1)(B).
- add this value to the estimated pressure in
the combustion chamber.
Example - RS 35/M BLU:
• Required burner maximum output operation:
350 kW
• Natural gas G 20 PCI 9.45 kWh/Sm
3
• Gas pressure at burner output of 350 kW,
taken from table RS 35/M BLU,
column 1
=6.5 mbar
• Pressure in combustion chamber
= 2 mbar
6.5 + 2 =8.5 mbar
pressure required at test point 1)(B).
(A)
(B)
2
VS
VR
R
3
1
F
RS 25/M BLU
∆
p (mbar)
RS 35/M BLU
∆
p (mbar)
kW
1
2
3
MB 405
3970500
MB 407
3970553
MB 410
3970554
MB 412
3970144
MB 415
3970180
MB 420
3970181
3970182
125
1.6
0.1
14.7
8.0
4.2
2.2
-
-
160
3.4
0.1
23.0
12.6
6.4
3.2
-
-
200
5.4
0.1
32.8
18.2
9.1
4.5
-
-
240
7.5
0.2
44.0
24.8
12.4
6.1
3.5
-
280
9.7
0.3
32.6
16.1
7.8
4.5
3.2
320
12.6
0.4
41.2
20.0
9.6
5.4
3.7
360
15.5
0.5
50.5
24.0
11.8
6.4
4.4
370
16.2
0.5
52.8
25.0
12.4
6.6
4.6
kW
1
2
3
MB 407
3970553
MB 410
3970554
MB 412
3970144
MB 415
3970180
MB 420
3970181
3970182
200
2.3
0.1
18.2
9.1
4.5
-
-
250
3.7
0.2
26.4
13.2
6.5
3.8
-
300
5.1
0.3
36.9
18.1
8.7
4.9
3.4
350
6.5
0.4
48.2
23.0
11.3
6.1
4.3
400
8.1
0.6
28.3
14.1
7.4
5.2
450
9.8
0.7
34.1
17.0
8.8
6.1
480
10.8
0.8
37.7
18.7
9.6
6.7
D3790
Содержание 3910510
Страница 63: ...20 RS 25 M BLU ...
Страница 64: ...21 RS 35 M BLU 1Ph ...
Страница 65: ...22 RS 25 35 M BLU 1Ph ...
Страница 66: ...23 RS 35 M BLU 3Ph ...
Страница 67: ...24 RS 35 M BLU 3Ph ...
Страница 68: ...25 RS 25 35 M BLU 1Ph 3Ph ...
Страница 69: ...26 RS 25 35 M BLU 1Ph 3Ph ...
