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51
Connecting the Gas Supply
4.1 Gas Pipe Sizing Tables
The following tables are referenced from the 2012 National Fuel Gas Code and are for reference only. Please
consult the gas pipe manufacturer for actual pipe capacities.
Maximum Natural Gas Delivery Capacity
In Cubic Feet (ft
3
) per Hour (0.60 Specific Gravity; 0.5 in WC Pressure Drop). Contact your gas supplier for BTU/ft
3
ratings.
Use 1,000 BTU/ft
3
for simplified calculations. This table is recommended for supply pressures less than 6 in WC.
Pipe
Size
Length (including fittings)
10 ft
(3 m)
20 ft
(6 m)
30 ft
(9 m)
40 ft
(12 m)
50 ft
(15 m)
60 ft
(18 m)
70 ft
(21 m)
80 ft
(24 m)
90 ft
(27 m)
100 ft
(30 m)
125 ft
(38 m)
3
/
4
in
360
247
199
170
151
137
126
117
110
104
92
1 in
678
466
374
320
284
257
237
220
207
195
173
1
1
/
4
in
1,390
957
768
657
583
528
486
452
424
400
355
1
1
/
2
in
2,090
1,430
1,150
985
873
791
728
677
635
600
532
2 in
4,020
2,760
2,220
1,900
1,680
1,520
1,400
1,300
1,220
1,160
1,020
2
1
/
2
in
6,400
4,400
3,530
3,020
2,680
2,430
2,230
2,080
1,950
1,840
1,630
3 in
11,300 7,780
6,250
5,350
4,740
4,290
3,950
3,670
3,450
3,260
2,890
4 in
23,100 15,900 12,700 10,900 9,660
8,760
8,050
7,490
7,030
6,640
5,890
In Cubic Feet (ft
3
) per Hour (0.60 Specific Gravity; 3.0 in WC Pressure Drop). Contact your gas supplier for BTU/ft
3
ratings. Use 1,000 BTU/ft
3
for simplified calculations. This table is recommended for supply pressures of 6 in WC or
greater.
Pipe
Size
Length (including fittings)
10 ft
(3 m)
20 ft
(6 m)
30 ft
(9 m)
40 ft
(12 m)
50 ft
(15 m)
60 ft
(18 m)
70 ft
(21 m)
80 ft
(24 m)
90 ft
(27 m)
100 ft
(30 m)
125 ft
(38 m)
1
/
2
in
454
312
250
214
190
172
158
147
138
131
116
3
/
4
in
949
652
524
448
397
360
331
308
289
273
242
1 in
1,787
1,228
986
844
748
678
624
580
544
514
456
1
1
/
4
in
3,669
2,522
2,025
1,733
1,536
1,392
1,280
1,191
1,118
1,056
936
1
1
/
2
in
5,497
3,778
3,034
2,597
2,302
2,085
1,919
1,785
1,675
1,582
1,402
2 in
10,588 7,277
5,844
5,001
4,433
4,016
3,695
3,437
3,225
3,046
2,700
2
1
/
2
in
16,875 11,598 9,314
7,971
7,065
6,401
5,889
5,479
5,140
4,856
4,303
3 in
29,832 20,503 16,465 14,092 12,489 11,316 10,411 9,685
9,087
8,584
7,608
4 in
43,678 30,020 24,107 20,632 18,286 16,569 15,243 14,181 13,305 12,568 11,139
Summary of Contents for NFB-175H
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