
Parker Hannifin Corporation
Parflex Division
Ravenna, Ohio
Bulletin No. 4660-PGP2T
Parflex
®
Flexible Gas Piping System
Design and Installation Guide
Section 7.0 Sizing Tables
7.2 Schedule 40 Metallic Pipe Table
Table 17
Maximum Capacity of Steel IPS Pipe in Cubic Feet per Hour
Gas Pressure: 0.5 psig oe less; Pressure Drop: 0.5 psig
(Based on a 0.60 Specific Gravity Gas)
Pipe Size
(in)
Diameter
(in)
10
20
30
40
50
60
70
80
90
100
125
150
175
200
1/4
0.36
43
29
24
20
18
16
15
14
13
12
11
10
9
8
3/8
0.49
95
65
52
45
40
36
33
31
29
27
24
22
20
19
1/2
0.62
175
120
97
82
73
66
61
57
53
50
44
40
37
35
3/4
0.82
360
250
200
170
151
138
125
118
110
103
93
84
77
72
1
1.05
680
465
375
320
285
260
240
220
205
195
175
160
145
135
1-1/4
1.38
1400
950
770
660
580
530
490
460
430
400
360
325
300
280
1-1/2
1.61
2100 1460 1180
990
900
810
750
690
650
620
550
500
460
430
2
2.07
3950 2750 2200 1900 1680 1520 1400 1300 1220 1150 1020
950
850
800
2-1/2
2.47
6300 4350 3520 3000 2650 2400 2250 2050 1950 1850 1650 1500 1370 1280
3
3.07
11000 7700 6250 5300 4750 4300 3900 3700 3450 3250 2950 2650 2450 2280
4
4.03
23000 15800 12800 10900 9700 8800 8100 7500 7200 6700 6000 5500 5000 4600
* Table reproduced from National Fuel Gas Code NFPA-54.
Specific Gravity Factor
— Systems that are to be supplied with a gas of a specific gravity other than 0.60 for natural
gas or 1.52 for propane shall apply a specific gravity factor. This conversion is accomplished by multiplying the
flow capacities given in Tables 1 through 13 and on the pressure drop graph by the appropriate multiplier shown
in the table below. If the exact specific gravity is not shown in the table, use the next higher specific gravity
shown.
Specific
Gravity
Conversion
Multiplier
Specific
Gravity
Conversion
Multiplier
0.35
1.31
1.00
0.78
0.40
1.23
1.10
0.74
0.45
1.16
1.20
0.71
0.50
1.10
1.30
0.68
0.55
1.04
1.40
0.66
0.60
1.00
1.50
0.63
0.65
0.96
1.60
0.61
0.70
0.93
1.70
0.59
0.75
0.90
1.80
0.58
0.80
0.87
1.90
0.56
0.85
0.84
2.00
0.55
0.90
0.82
2.10
0.54
7.3 Specific Gravity