Note that this estimate is close to the HLf predicted inFig. 17-19 for elevation pressure drop determination. It alsocoincides closely with the value of 0.16 from Fig. 17-18.

Calculate the pipeline segment liquid inventory from Eq 17- 57

IL = (7.853) (10−7) (0.14) (152.4 )2 (1200) = 3.064 m3

The pipeline segment contains 3.064 cubic m of liquid at anyinstant.

Liquid Slugging

Purpose of Separators — The slug flow regime is fre-quently encountered for pipe sizes and flow rates used in proc-ess and transmission piping. Liquid slugging introduces anadditional design and operational difficulty as liquid and va-por must generally be separated at the downstream end of thetwo-phase flow line. The downstream separator serves both asa liquid-vapor disengaging device and as a surge vessel to ab-sorb the fluctuating liquid flow rates caused by slugging. Inorder to size the separator or slug catcher, the length of theincoming slugs must be determined. Slug length calculationmethods are not well developed, and there is large uncertaintyin slug length determination.

Mechanisms of Slug Generation — Liquid slug lengthsare difficult to determine in part because there are at leastfour identifiable mechanisms for liquid slug generation. Slugscan form as the result of wave formation at the liquid-gas in-terface in a stratified flow. When the liquid waves grow largeenough to bridge the entire pipe diameter, the stratified flowpattern breaks down and a slug flow is formed.

Slugs can also form due to terrain effects. Liquid collects ata sag in the pipeline and blocks the gas flow. The pressure inthis blocked gas rises until it blows the accumulated liquid inthe sag out as a slug. Changes in pipeline inlet flow rate canalso cause slugs. When the inlet flow rate increases, the liquidinventory in the pipeline decreases, and the excess liquidforms a slug or series of slugs. Finally, pigging can cause verylarge liquid slugs as the entire liquid inventory of the line isswept ahead of the pig. Of the four mechanisms described,wave growth normally produces the shortest slugs, followedin length by terrain generated slugs. Methods for calculating

wave induced slugs were described by Greskovich andShrier22, and by Brill et al.23 A preliminary scheme for calcu-lating terrain generated slugs was reported by Schmidt.24

Analytical methods for determining inlet flow rate generatedslugs were given by Cunliffe,25 and a method of analyzing pig-ging dynamics was given by McDonald and Baker.26

Slug Catchers — Slug catchers are devices at the down-stream end or other intermediate points of a pipeline to absorbthe fluctuating liquid inlet flow rates through liquid level fluc-tuation. Slug catchers may be either a vessel or constructed ofpipe. All size specifications discussed in Section 7 to provideresidence time for vapor-liquid disengagement also apply tovessels used as slug catchers. In addition, sufficient volumemust be provided for liquid level fluctuation. Particularly forhigh pressure service, vessel separators may require verythick walls.

In order to avoid thick wall vessels, slug catchers are fre-quently made of pipe. Lengths of line pipe tens or hundreds offeet long are used as long, slender horizontal separators. Thepipe is generally inclined from one to ten degrees and banksof these slightly inclined pipes are frequently manifolded to-gether. Pipe type slug catchers are frequently less expensivethan vessel type slug catchers of the same capacity due to thin-ner wall requirements of smaller diameter pipe. The manifoldnature of multiple pipe slug catchers also makes possible thelater addition of additional capacity by laying more parallelpipes. A schematic of a multiple pipe (harp) slug catcher ap-pears in Fig. 17-21. Different pipe inclinations and differentmanifolding arrangements are favored by different designers.

An example of a line drip catcher is shown in Fig. 17-22. Adrip vessel is connected to the incoming pipeline and often laidbeneath it. A flow line from the drip vessel is used to blow theliquids out to a storage or surge vessel as they accumulate.

Pigging — Pipelines are pigged for several reasons. If wateris present in the line, it must be removed periodically in order tominimize corrosion. This water accumulates in sags in the pipe-line, and these low spots are particularly susceptible to corrosion.Pipelines are also pigged to improve pressure drop-flow rate per-formance. Water or hydrocarbon liquids that settle in sags in thepipeline constitute partial blockages that increase pressure drop.

INLET

SLOPED

VAPOROUTLET

LIQUIDOUTLET

FIG. 17-21

Multiple Pipe Slug Catcher

GRADE

GAS FLOW

DRIP LIQUID

DRIPVALVE

NO

DRIPBELOWLINE

DRIPVESSEL

FIG. 17-22

Example Line Drip

17-21

Pigging can remove these liquids and improve pipeline effi-ciency. Pigging can also be used as a means of limiting therequired slug catcher size. By pigging at frequent intervals,liquid inventory buildup in a pipeline can be reduced, and themaximum slug size can be limited. The required downstreamslug catcher size must take into account pigging frequency.

Operational hazards are associated with pigging. The verylarge slugs swept ahead of the pig may overwhelm inade-quately sized downstream facilities. Pigs may also occasion-ally be destroyed in the pipeline and the resulting debris maydamage downstream fittings or equipment. Even worse, thepig may become stuck in the line and require an expensiveshutdown for location and removal.

PIPE AND FLANGE DATA

The Petroleum Refinery Piping Code (ANSI B31.3) is usedto determine the allowable pressure limits for piping insiderefineries and other processing facilities. Refer to Fig. 17-23for the calculation method.

The table of allowable stresses, Fig. 17-25, is extracted fromANSI B31.3. The designer is strongly urged to consult the lat-est ANSI B31.3 publication for full description of the code. Atabular compilation of maximum allowable working pressurescalculated according to ANSI B31.3 appears in Fig. 17-26.

For piping outside of refineries and other processing facili-ties, a separate code applies for determining allowable pres-

sure limits, ANSI B31.8. Refer to Fig. 17-24 for the calculationmethod.

The designer is encouraged to refer to the latest ANSI B31.8standard for comprehensive code description. A tabular com-pilation of maximum allowable working pressures computedaccording to ANSI B31.8 appears in Fig. 17-27.

Fig. 17-28 provides pressure ratings for steel flanges andflanged fittings.

To determine allowable internal working pressure forstraight sections of pipe in accordance with ANSI B31.3,“Code for Pressure Piping, Petroleum Refinery Piping”,use the following:

tm = t + c

t = Pido

2(S′E′ + PiY′) or Pi =

2 tS′E′do − 2 tY′

where:

tm = minimum required thickness, satisfying

requirements for pressure, and mechanical,

corrosion, and erosion allowances, mm. (The

minimum thickness for the pipe selected, con-

sidering manufacturer’s minus tolerance,

shall not be less than tm).

t = pressure design thickness, mm

c = the sum of the mechanical allowances

(thread depth and groove depth), corrosion,

and erosion allowances, mm

Pi = internal design pressure, kPa (ga)

do = outside diameter of pipe, mm

S′ = allowable stresses, kPa

E′ = longitudinal weld joint factor:

Seamless = 1.000, ERW = 0.85

Y′ = coefficient having values for ferritic steels

as follows: 0.4 up to and including 480°C

0.5 for 510°C

0.7 for 540°C and above

FIG. 17-23

Working Pressures Refinery Piping

To determine allowable internal working pressures for pip-ing outside of refineries and other processing facilities inaccordance with ANSI B31.8-1992, “Code of Pressure Pip-ing, Gas Transmission and Distribution Piping,” use thefollowing:

Pi = 2 S′′ t

do

(F′′) (E′′) (T′′)

Where

Pi = Design pressure, kPa (ga)

S′′ = Specified minimum yield strength, kPa

do = Nominal outside diameter, mm

t = Nominal wall thickness, mm

F′′ = Construction type design factor,

Table 841.114A and Par. 840.2 (see note)

Location Class F′′

1 Div 1 .80

Div 2 .72

Div 2 .60

Div 3 .50

Div 4 .40

Complete details are covered in Par. 841.

E′′ = Longitudinal joint factor, Table 841.115A

Normally a factor of 1.0 is used for seamless

and welded pipe except for the following:

Fusion Welded A 134 and A 139 0.80

Spiral Welded A 211 0.80

Furnace Butt Welded ASTM-A53, API-5L 0.60

T′′ = Temperature derating factor, Table 841.116A

Temp, °C Factor T′′

120 or less 1.000

150 0.967

175 0.933

200 0.900

230 0.867

For intermediate temperatures, interpolate for

derating factor.

Note: Factor reflecting location of line, proximity to roads,public or private land, etc.

FIG. 17-24

Working Pressures Transmission Lines

17-22

FIG

. 17-2

5

Allo

wab

le S

tresses in

Ten

sio

n f

or

Mate

rials

(1)

(Excerp

ted

fro

m A

NS

I B

31.3

a-1

985, A

pp

en

dix

A, Tab

les A

-1, A

-1B

)

17-23

Nompipesizein.

Sch.No.

Weight of pipe

kg/meterO.D.mm

Wall thk.mm

I D mm(d)

Flowareamm

2

Allowable working pressures for temperatures (in °C) not to exceed, Mpa (ga).

–29 to 38 93 149 204 260 316 371

1/2 S40 1.27 21.3 2.8 15.8 196 15.57 15.57 15.57 15.57 14.72 13.47 12.85

3/4 S40 1.69 26.7 2.9 20.9 344 13.33 13.33 13.33 13.33 12.60 11.53 11.00

X80 2.20 3.9 18.8 279 23.80 23.80 23.80 23.80 22.49 20.59 19.63

1 S40 2.50 33.4 3.4 26.6 558 14.50 14.50 14.50 14.50 13.71 12.54 11.97

X80 3.24 4.5 24.3 464 23.92 23.92 23.92 23.92 22.60 20.69 19.73

160 4.24 6.4 20.7 337 39.45 39.45 39.45 39.45 37.28 34.12 32.54

XX 5.46 9.1 15.2 182 65.75 65.75 65.75 65.75 62.14 56.88 54.25

1-1/2 S40 4.05 48.3 3.7 40.9 1 313 11.53 11.53 11.53 11.53 10.90 9.97 9.51

X80 5.41 5.1 38.1 1 140 19.15 19.15 19.15 19.15 18.10 16.57 15.80

160 7.25 7.1 34.0 907 30.99 30.99 30.99 30.99 29.29 26.81 25.57

XX 9.56 10.2 27.9 613 49.85 49.85 49.85 49.85 47.11 43.12 41.12

2 S40 5.45 60.3 3.9 52.5 2 165 10.13 10.13 10.13 10.13 9.57 8.76 8.36

X80 7.49 5.5 49.3 1 905 17.16 17.16 17.16 17.16 16.21 14.84 14.16

160 11.10 8.7 42.8 1 442 31.72 31.72 31.72 31.72 29.98 27.44 26.17

XX 13.46 11.1 38.2 1 145 43.34 43.34 43.34 43.34 40.96 37.49 35.76

3 S40 11.30 88.9 5.5 77.9 4 769 11.31 11.31 11.31 11.31 10.69 9.79 9.33

X80 15.28 7.6 73.7 4 261 17.60 17.60 17.60 17.60 16.63 15.22 14.52

160 21.36 11.1 66.6 3 489 28.43 28.43 28.43 28.43 26.86 24.59 23.46

XX 27.70 15.2 58.4 2 680 41.99 41.99 41.99 41.99 39.68 36.32 34.65

4 S40 16.09 114.3 6.0 102.3 8 213 9.92 9.92 9.92 9.92 9.38 8.58 8.19

X80 22.35 8.6 97.2 7 417 15.69 15.69 15.69 15.69 14.83 13.57 12.94

160 33.56 13.5 87.3 5 989 27.43 27.43 27.43 27.43 25.93 23.73 22.63

XX 41.06 17.1 80.1 5 034 36.60 36.60 36.60 36.60 34.59 31.66 30.19

6 S40 28.30 168.3 7.1 154.1 18 639 8.31 8.31 8.31 8.31 7.86 7.19 6.86

X80 42.61 11.0 146.3 16 817 14.22 14.22 14.22 14.22 13.43 12.30 11.73

160 67.54 18.2 131.7 13 633 25.88 25.88 25.88 25.88 24.46 22.39 21.36

XX 79.27 21.9 124.4 12 151 32.13 32.13 32.13 32.13 30.37 27.79 26.51

8 S40 42.58 219.1 8.2 202.7 32 275 7.57 7.57 7.57 7.57 7.15 6.55 6.25

X80 64.71 12.7 193.7 29 460 12.86 12.86 12.86 12.86 12.14 11.12 10.60

XX 107.94 22.2 174.6 23 950 24.51 24.51 24.51 24.51 23.17 21.20 20.22

160 111.37 23.0 173.1 23 520 25.51 25.51 25.51 25.51 24.11 22.07 21.05

10 S40 60.38 273.1 9.3 254.5 50 874 7.05 7.05 7.05 7.05 6.66 6.10 5.81

X60 81.55 12.7 247.7 48 169 10.23 10.23 10.23 10.23 9.68 8.86 8.44

160 172.50 28.6 215.9 36 610 25.77 25.77 25.77 25.77 24.35 22.29 21.26

12 S 73.95 323.9 9.5 304.8 72 966 6.12 6.12 6.12 6.12 5.79 5.30 5.05

X 97.51 12.7 298.5 69 957 8.59 8.59 8.59 8.59 8.12 7.43 7.08

160 238.99 33.3 257.2 51 956 25.51 25.51 25.51 25.51 24.11 22.07 21.05

14 10 54.72 355.6 6.4 342.9 92 347 3.35 3.35 3.35 3.35 3.17 2.90 2.77

S30 81.40 9.5 336.6 88 959 5.57 5.57 5.57 5.57 5.26 4.81 4.59

X 107.49 12.7 330.2 85 634 7.81 7.81 7.81 7.81 7.37 6.75 6.44

16 10 62.77 406.4 6.4 393.7 121 736 2.93 2.93 2.93 2.93 2.77 2.54 2.42

S30 93.33 9.5 387.4 117 841 4.86 4.86 4.86 4.86 4.59 4.20 4.01

S40 123.45 12.7 381.0 114 009 6.81 6.81 6.81 6.81 6.43 5.89 5.62

18 10 70.67 457.2 6.4 444.5 155 179 2.60 2.60 2.60 2.60 2.46 2.25 2.14

S 105.26 9.5 438.2 150 777 4.31 4.31 4.31 4.31 4.08 3.73 3.56

X 139.40 12.7 431.8 146 438 6.04 6.04 6.04 6.04 5.71 5.22 4.98

20 10 78.57 508.0 6.4 495.3 192 676 2.34 2.34 2.34 2.34 2.21 2.02 1.93

S20 117.19 9.5 489.0 187 767 3.88 3.88 3.88 3.88 3.66 3.35 3.20

X30 155.20 12.7 472.6 182 921 5.43 5.43 5.43 5.43 5.12 4.69 4.48

24 10 94.52 609.6 6.4 596.9 279 829 1.94 1.94 1.94 1.94 1.84 1.68 1.61

S20 141.04 9.5 590.6 273 907 3.23 3.22 3.22 3.22 3.05 2.79 2.66

X 187.11 12.7 584.2 268 048 4.55 4.51 4.51 4.51 4.26 3.90 3.72

Note: The above allowable working pressures are calculated from Fig. 17-23 using a reduction in tm to 87.5% of the wall thickness shown above to recognize mill

wall tolerance of 12.5%.

FIG. 17-26

Design Properties and Allowable Working Pressures for Piping

ASTM A106, grade B seamless pipe—Petroleum Refinery Piping Code

for Pressure Piping ANSI B31.3-1984—Corrosion allowance = 0.05

17-24

NomPipeSizein.

O.D.mm

WallThk.mm

Allowable Working Pressures up to 120°C, in MPa (ga)

Construction Type Design Factors

Type A, F = 0.72* Type B, F = 0.60 Type C, F = 0.50 Type D, F = 0.40

GR.B GR.B GR.B GR.B

241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8

2(STD) 3.9 22.5 18.8 15.7 12.5

60.3 5.5 31.9 26.6 22.2 17.7

3

3.2 12.4 20.7 10.3 8.6 6.9

4.0 15.5 12.9 10.8 8.6

88.9 4.8 18.7 15.6 13.0 10.4

(STD) 5.5 21.4 17.9 14.9 11.9

6.4 24.8 20.7 17.2 13.8

7.1 27.9 23.3 19.4 15.5

7.6 29.8 24.8 20.7 16.6

4

3.2 9.7 11.6 12.7 8.0 9.7 10.6 6.7 8.0 8.8 5.4 6.4 7.0

4.0 12.0 14.5 15.8 10.0 12.0 13.2 8.4 10.0 11.0 6.7 8.0 8.8

4.8 14.5 17.4 19.1 12.1 14.5 15.9 10.1 12.1 13.3 8.1 9.7 10.6

114.3 5.6 16.9 20.3 22.2 14.1 16.9 18.5 11.8 14.1 15.4 9.4 11.3 12.4

(STD) 6.0 18.3 22.0 24.1 15.3 18.3 20.0 12.7 15.3 16.7 10.2 12.2 13.4

6.4 19.3 23.2 25.4 16.1 19.3 21.2 13.4 16.1 17.6 10.7 12.9 14.1

7.1 21.7 26.0 28.5 18.1 21.7 23.8 15.1 18.1 19.8 12.1 14.5 15.8

7.9 24.1 28.9 31.7 20.1 24.1 26.4 16.7 20.1 22.0 13.4 16.1 17.6

8.6 26.0 31.2 34.2 21.7 26.0 28.5 18.1 21.7 23.8 14.5 17.4 19.0

6

4.0 8.2 9.8 10.8 12.2 6.8 8.2 9.0 10.1 5.7 6.8 7.5 8.4 4.5 5.5 6.0 6.8

4.8 9.9 11.8 13.0 14.6 8.2 9.9 10.8 12.2 6.8 8.2 9.0 10.2 5.5 6.6 7.2 8.1

5.6 11.5 13.8 15.1 17.1 9.6 11.5 12.6 14.2 8.0 9.6 10.5 11.9 6.4 7.7 8.4 9.5

168.3 6.4 13.1 15.7 17.2 19.5 10.9 13.1 14.4 16.2 9.1 10.9 12.0 13.5 7.3 8.7 9.6 10.8

(STD) 7.1 14.7 17.6 19.3 21.8 12.2 14.7 16.1 18.2 10.2 12.2 13.4 15.2 8.2 9.8 10.7 12.1

7.9 16.4 19.6 21.5 24.3 13.6 16.4 17.9 20.2 11.4 13.6 14.9 16.9 9.1 10.9 12.0 13.5

9.5 19.7 23.6 25.9 29.2 16.4 19.7 21.6 24.4 13.7 16.4 18.0 20.3 10.9 13.1 14.4 16.2

11.0 22.7 27.2 29.8 33.7 18.9 22.7 24.8 28.1 15.7 18.9 20.7 23.4 12.6 15.1 16.6 18.7

8

4.0 6.3 7.5 8.3 9.3 5.2 6.3 6.9 7.8 4.4 5.2 5.7 6.5 3.5 4.2 4.6 5.2

4.8 7.6 9.1 10.0 11.3 6.3 7.6 8.3 9.4 5.3 6.3 6.9 7.8 4.2 5.0 5.5 6.3

5.2 8.2 9.8 10.8 12.2 6.8 8.2 9.0 10.1 5.7 6.8 7.5 8.4 4.5 5.5 6.0 6.8

5.6 8.8 10.6 11.6 13.1 7.4 8.8 9.7 10.9 6.1 7.4 8.1 9.1 4.9 5.9 6.4 7.3

6.4 10.1 12.1 13.2 15.0 8.4 10.1 11.0 12.5 7.0 8.4 9.2 10.4 5.6 6.7 7.4 8.3

219.1 7.0 11.2 13.4 14.7 16.6 9.3 11.2 12.2 13.8 7.8 9.3 10.2 11.5 6.2 7.4 8.2 9.2

7.9 12.6 15.1 16.5 18.7 10.5 12.6 13.8 15.6 8.7 10.5 11.5 13.0 7.0 8.4 9.2 10.4

(STD) 8.2 13.0 15.6 17.1 19.3 10.8 13.0 14.2 16.1 9.0 10.8 11.8 13.4 7.2 8.6 9.5 10.7

8.7 13.9 16.6 18.2 20.6 11.6 13.9 15.2 17.2 9.6 11.6 12.7 14.3 7.7 9.2 10.1 11.4

9.5 15.1 18.1 19.9 22.5 12.6 15.1 16.5 18.7 10.5 12.6 13.8 15.6 8.4 10.1 11.0 12.5

11.1 17.7 21.2 23.2 26.2 14.7 17.7 19.3 21.9 12.3 14.7 16.1 18.2 9.8 11.8 12.9 14.6

12.7 20.2 24.2 26.5 29.9 16.8 20.2 22.1 24.9 14.0 16.8 18.4 20.8 11.2 13.4 14.7 16.6

10

4.8 6.1 7.3 8.0 9.0 5.1 6.1 6.7 7.5 4.2 5.1 5.5 6.3 3.4 4.1 4.4 5.0

5.2 6.6 7.9 8.6 9.8 5.5 6.6 7.2 8.1 4.6 5.5 6.0 6.8 3.6 4.4 4.8 5.4

5.6 7.1 8.5 9.3 10.5 5.9 7.1 7.8 8.8 4.9 5.9 6.5 7.3 3.9 4.7 5.2 5.8

6.4 8.1 9.7 10.6 12.0 6.7 8.1 8.9 10.0 5.6 6.7 7.4 8.3 4.5 5.4 5.9 6.7

273.1 7.1 9.0 10.8 11.9 13.4 7.5 9.0 9.9 11.2 6.3 7.5 8.2 9.3 5.0 6.0 6.6 7.4

7.8 9.9 11.9 13.0 14.7 8.3 9.9 10.9 12.3 6.9 8.3 9.1 10.2 5.5 6.6 7.2 8.2

8.7 11.1 13.3 14.6 16.5 9.3 11.1 12.2 13.8 7.7 9.3 10.2 11.5 6.2 7.4 8.1 9.2

(STD) 9.3 11.8 14.2 15.5 17.5 9.8 11.8 12.9 14.6 8.2 9.8 10.8 12.2 6.6 7.9 8.6 9.7

11.1 14.2 17.0 18.6 21.0 11.8 14.2 15.5 17.5 9.8 11.8 12.9 14.6 7.9 9.4 10.3 11.7

12.7 16.2 19.4 21.2 24.0 13.5 16.2 17.7 20.0 11.2 13.5 14.8 16.7 9.0 10.8 11.8 13.3

12

4.8 5.1 6.2 6.7 7.6 4.3 5.1 5.6 6.3 3.6 4.3 4.7 5.3 2.8 3.4 3.7 4.2

5.2 5.5 6.6 7.3 8.2 4.6 5.5 6.1 6.9 3.8 4.6 5.1 5.7 3.1 3.7 4.0 4.6

5.6 6.0 7.2 7.8 8.9 5.0 6.0 6.5 7.4 4.1 5.0 5.4 6.2 3.3 4.0 4.4 4.9

6.4 6.8 8.2 9.0 10.1 5.7 6.8 7.5 8.4 4.7 5.7 6.2 7.0 3.8 4.5 5.0 5.6

7.1 7.7 9.2 10.1 11.4 6.4 7.7 8.4 9.5 5.3 6.4 7.0 7.9 4.3 5.1 5.6 6.3

323.9 7.9 8.5 10.2 11.2 12.6 7.1 8.5 9.3 10.5 5.9 7.1 7.8 8.8 4.7 5.7 6.2 7.0

8.4 9.0 10.8 11.8 13.4 7.5 9.0 9.9 11.1 6.2 7.5 8.2 9.3 5.0 6.0 6.6 7.4

8.7 9.4 11.2 12.3 13.9 7.8 9.4 10.3 11.6 6.5 7.8 8.6 9.7 5.2 6.2 6.8 7.7

(STD) 9.5 10.2 12.3 13.4 15.2 8.5 10.2 11.2 12.7 7.1 8.5 9.3 10.5 5.7 6.8 7.5 8.4

10.3 11.1 13.3 14.6 16.4 9.2 11.1 12.1 13.7 7.7 9.2 10.1 11.4 6.2 7.4 8.1 9.1

11.1 11.9 14.3 15.7 17.7 10.0 11.9 13.1 14.8 8.3 10.0 10.9 12.3 6.6 8.0 8.7 9.9

12.7 13.6 16.4 17.9 20.2 11.4 13.6 14.9 16.9 9.5 11.4 12.4 14.1 7.6 9.1 10.0 11.2

* Type A construction also applicable to "Liquid Petroleum Transportation Piping Code," ANSI B31.4-1979

FIG. 17-27

Gas Transmission and Distribution Piping

Code for Pressure Piping ANSI B31.8-1982

Carbon Steel and High Yield Strength Pipe

(Values apply to A106, API 5L and API 5LX pipe having the same specified minimum yield strength as shown)

17-25

NomPipeSizein.

O.D.mm

WallThk.mm

Allowable Working Pressures up to 120°C, in MPa (ga)

Construction Type Design Factors

Type A, F = 0.72* Type B, F = 0.60 Type C, F = 0.50 Type D, F = 0.40

GR.B GR.B GR.B GR.B

241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8 241.4 289.7 317.2 358.6 413.8

16

5.6 4.8 5.7 6.2 7.1 8.2 4.0 4.8 5.2 5.9 6.8 3.3 4.0 4.3 4.9 5.7 2.6 3.2 3.5 3.9 4.5

6.4 5.4 6.5 7.1 8.1 9.3 4.5 5.4 6.0 6.7 7.8 3.8 4.5 5.0 5.6 6.5 3.0 3.6 4.0 4.5 5.2

7.1 6.1 7.3 8.0 9.1 10.5 5.1 6.1 6.7 7.6 8.7 4.2 5.1 5.6 6.3 7.3 3.4 4.1 4.5 5.0 5.8

7.9 6.8 8.1 8.9 10.1 11.6 5.6 6.8 7.4 8.4 9.7 4.7 5.6 6.2 7.0 8.1 3.8 4.5 4.9 5.6 6.5

406.4 8.7 7.5 9.0 9.8 11.1 12.8 6.2 7.5 8.2 9.2 10.7 5.2 6.2 6.8 7.7 8.9 4.2 5.0 5.5 6.2 7.1

(STD) 9.5 8.1 9.8 10.7 12.1 14.0 6.8 8.1 8.9 10.1 11.6 5.7 6.8 7.4 8.4 9.7 4.5 5.4 6.0 6.7 7.8

11.1 9.5 11.4 12.5 14.1 16.3 7.9 9.5 10.4 11.8 13.6 6.6 7.9 8.7 9.8 11.3 5.3 6.3 6.9 7.8 9.1

12.7 10.9 13.0 14.3 16.1 18.6 9.1 10.9 11.9 13.4 15.5 7.5 9.1 9.9 11.2 12.9 6.0 7.2 7.9 9.0 10.3

15.9 13.6 16.3 17.8 20.2 23.3 11.3 13.6 14.9 16.8 19.4 9.4 11.3 12.4 14.0 16.2 7.5 9.1 9.9 11.2 12.9

20

6.4 4.3 5.2 5.7 6.5 7.4 3.6 4.3 4.8 5.4 6.2 3.0 3.6 4.0 4.5 5.2 2.4 2.9 3.2 3.6 4.1

7.1 4.9 5.9 6.4 7.3 8.4 4.1 4.9 5.4 6.1 7.0 3.4 4.1 4.5 5.0 5.8 2.7 3.3 3.6 4.0 4.6

7.9 5.4 6.5 7.1 8.1 9.3 4.5 5.4 5.9 6.7 7.7 3.8 4.5 5.0 5.6 6.5 3.0 3.6 4.0 4.5 5.2

8.7 6.0 7.2 7.9 8.9 10.2 5.0 6.0 6.6 7.4 8.5 4.2 5.0 5.5 6.2 7.1 3.3 4.0 4.4 4.9 5.7

(STD) 9.5 6.5 7.8 8.6 9.7 11.2 5.4 6.5 7.1 8.1 9.3 4.5 5.4 6.0 6.7 7.8 3.6 4.3 4.8 5.4 6.2

508.0 10.3 7.1 8.5 9.3 10.5 12.1 5.9 7.1 7.7 8.7 10.1 4.9 5.9 6.4 7.3 8.4 3.9 4.7 5.2 5.8 6.7

11.1 7.6 9.1 10.0 11.3 13.0 6.3 7.6 8.3 9.4 10.9 5.3 6.3 6.9 7.8 9.1 4.2 5.1 5.6 6.3 7.2

12.7 8.7 10.4 11.4 12.9 14.9 7.2 8.7 9.5 10.8 12.4 6.0 7.2 7.9 9.0 10.3 4.8 5.8 6.3 7.2 8.3

15.9 10.9 13.0 14.3 16.1 18.6 9.1 10.9 11.9 13.4 15.5 7.5 9.1 9.9 11.2 12.9 6.0 7.2 7.9 9.0 10.3

19.1 13.0 15.6 17.1 19.4 22.3 10.9 13.0 14.3 16.1 18.6 9.1 10.9 11.9 13.4 15.5 7.2 8.7 9.5 10.8 12.4

24

7.1 4.1 4.9 5.4 6.0 7.0 3.4 4.1 4.5 5.0 5.8 2.8 3.4 3.7 4.2 4.8 2.3 2.7 3.0 3.4 3.9

7.9 4.5 5.4 5.9 6.7 7.7 3.8 4.5 5.0 5.6 6.5 3.1 3.8 4.1 4.7 5.4 2.5 3.0 3.3 3.7 4.3

8.7 5.0 6.0 6.5 7.4 8.5 4.2 5.0 5.5 6.2 7.1 3.5 4.2 4.5 5.1 5.9 2.8 3.3 3.6 4.1 4.7

(STD) 9.5 5.4 6.5 7.1 8.1 9.3 4.5 5.4 5.9 6.7 7.8 3.8 4.5 5.0 5.6 6.5 3.0 3.6 4.0 4.5 5.2

609.6 10.3 5.9 7.1 7.7 8.7 10.1 4.9 5.9 6.4 7.3 8.4 4.1 4.9 5.4 6.1 7.0 3.3 3.9 4.3 4.9 5.6

11.1 6.3 7.6 8.3 9.4 10.9 5.3 6.3 6.9 7.8 9.1 4.4 5.3 5.8 6.5 7.6 3.5 4.2 4.6 5.2 6.0

12.7 7.2 8.7 9.5 10.8 12.4 6.0 7.2 7.9 9.0 10.3 5.0 6.0 6.6 7.5 8.6 4.0 4.8 5.3 6.0 6.9

15.9 9.0 10.9 11.9 13.4 15.5 7.5 9.1 9.9 11.2 12.9 6.3 7.5 8.3 9.3 10.8 5.0 6.0 6.6 7.5 8.6

19.1 10.9 13.0 14.3 16.1 18.6 9.1 10.9 11.9 13.4 15.5 7.5 9.1 9.9 11.2 12.9 6.0 7.2 7.9 9.0 10.3

26

7.1 3.8 4.5 4.9 5.6 6.4 3.1 3.8 4.1 4.7 5.4 2.6 3.1 3.4 3.9 4.5 2.1 2.5 2.7 3.1 3.6

7.9 4.2 5.0 5.5 6.2 7.2 3.5 4.2 4.6 5.2 6.0 2.9 3.5 3.8 4.3 5.0 2.3 2.8 3.0 3.4 4.0

660.4 8.7 4.6 5.5 6.0 6.8 7.9 3.8 4.6 5.0 5.7 6.6 3.2 3.8 4.2 4.7 5.5 2.6 3.1 3.4 3.8 4.4

(STD) 9.5 5.0 6.0 6.6 7.4 8.6 4.2 5.0 5.5 6.2 7.2 3.5 4.2 4.6 5.2 6.0 2.8 3.3 3.7 4.1 4.8

10.3 5.4 6.5 7.1 8.1 9.3 4.5 5.4 6.0 6.7 7.8 3.8 4.5 5.0 5.6 6.5 3.0 3.6 4.0 4.5 5.2

11.1 5.8 7.0 7.7 8.7 10.0 4.9 5.8 6.4 7.2 8.4 4.1 4.9 5.3 6.0 7.0 3.2 3.9 4.3 4.8 5.6

12.7 6.7 8.0 8.8 9.9 11.5 5.6 6.7 7.3 8.3 9.6 4.6 5.6 6.1 6.9 8.0 3.7 4.5 4.9 5.5 6.4

15.9 8.4 10.0 11.0 12.4 14.3 7.0 8.4 9.2 10.3 11.9 5.8 7.0 7.6 8.6 9.9 4.6 5.6 6.1 6.9 8.0

19.1 10.0 12.0 13.2 14.9 17.2 8.4 10.0 11.0 12.4 14.3 7.0 8.4 9.2 10.3 11.9 5.6 6.7 7.3 8.3 9.6

30

7.9 3.6 4.3 4.8 5.4 6.2 3.0 3.6 4.0 4.5 5.2 2.5 3.0 3.3 3.7 4.3 2.0 2.4 2.6 3.0 3.4

8.7 4.0 4.8 5.2 5.9 6.8 3.3 4.0 4.4 4.9 5.7 2.8 3.3 3.6 4.1 4.7 2.2 2.7 2.9 3.3 3.8

(STD) 9.5 4.3 5.2 5.7 6.5 7.4 3.6 4.3 4.8 5.4 6.2 3.0 3.6 4.0 4.5 5.2 2.4 2.9 3.2 3.6 4.1

762.0 10.3 4.7 5.6 6.2 7.0 8.1 3.9 4.7 5.2 5.8 6.7 3.3 3.9 4.3 4.9 5.6 2.6 3.1 3.4 3.9 4.5

11.1 5.1 6.1 6.7 7.5 8.7 4.2 5.1 5.6 6.3 7.2 3.5 4.2 4.6 5.2 6.0 2.8 3.4 3.7 4.2 4.8

12.7 5.8 7.0 7.6 8.6 9.9 4.8 5.8 6.3 7.2 8.3 4.0 4.8 5.3 6.0 6.9 3.2 3.9 4.2 4.8 5.5

15.9 7.2 8.7 9.5 10.8 12.4 6.0 7.2 7.9 9.0 10.3 5.0 6.0 6.6 7.5 8.6 4.0 4.8 5.3 6.0 6.9

19.1 8.7 10.4 11.4 12.9 14.9 7.2 8.7 9.5 10.8 12.4 6.0 7.2 7.9 9.0 10.3 4.8 5.8 6.3 7.2 8.3

* Type A construction also applicable to "Liquid Petroleum Transportation Piping Code," ANSI B31.4-1979

Notes: 1. All dimensions are as shown

2. See Fig 17-24

FIG. 17-27 (Cont’d.)

Gas Transmission and Distribution Piping

17-26

CLASS 150 300 400 600 900 1500 2500 See Notes

Material Group 1.1 (Carbon Steel)

A105 (1)(3), A216−WCB (1), A515−70 (1) A516−70 (1) A350−LF2, A537−C1.1

(a) (h)(a) (g)

(d)

°C Pressures are in MPa (ga)

–29 to 38 1.97 5.10 6.83 10.21 15.31 25.55 42.55

93 1.79 4.66 6.21 9.31 13.97 23.28 38.79

149 1.59 4.52 6.03 9.07 13.59 22.62 37.72

204 1.38 4.38 5.83 8.76 13.10 21.86 36.41

260 1.17 4.14 5.52 8.28 12.38 20.66 34.41

316 0.97 3.79 5.03 7.55 11.31 18.86 31.45

343 0.86 3.69 4.93 7.41 11.10 18.52 30.86

371 0.76 3.69 4.90 7.34 11.03 18.38 30.62

399 0.66 3.48 4.62 6.97 10.41 17.38 28.97

427 0.55 2.83 3.79 5.69 8.52 14.21 23.66

454 0.45 1.86 2.45 3.69 5.55 9.24 15.38

482 0.34 1.17 1.59 2.38 3.55 5.93 9.86

510 0.24 0.72 0.97 1.41 2.14 3.55 5.93

538 0.14 0.34 0.48 0.72 1.07 1.79 2.97

Material Group 2.1 (Type 304)

A182−F304 (5), A182−F304H

A240−304 (5)(6), A351−CF8 (5) A351−CF3

——

(f)

–29 to 38 1.90 4.97 6.62 9.93 14.90 24.83 41.38

93 1.62 4.14 5.52 8.28 12.41 20.69 34.48

149 1.41 3.66 4.86 7.28 10.93 18.21 30.34

204 1.24 3.24 4.34 6.48 9.72 16.21 27.03

260 1.17 3.00 4.03 6.03 9.03 15.07 25.10

316 0.97 2.86 3.83 5.72 8.59 14.31 23.86

371 0.76 2.79 3.72 5.55 8.34 13.90 23.17

427 0.55 2.72 3.62 5.45 8.14 13.59 22.62

454 0.45 2.69 3.59 5.38 8.03 13.41 22.34

482 0.34 2.66 3.52 5.31 7.93 13.24 22.07

510 0.24 2.59 3.45 5.17 7.76 12.90 21.52

538 0.14 2.24 2.97 4.45 6.66 11.10 18.52

566 2.14 2.83 4.28 6.38 10.66 17.72

593 1.79 2.38 3.55 5.31 8.86 14.79

621 1.34 1.79 2.69 4.03 6.76 11.24

649 1.07 1.41 2.14 3.21 5.31 8.86

677 0.76 1.00 1.52 2.28 3.79 6.31

704 0.59 0.76 1.14 1.69 2.83 4.72

732 0.41 0.59 0.86 1.28 2.14 3.55

760 0.34 0.45 0.62 1.00 1.66 2.76

788 0.24 0.31 0.48 0.72 1.17 1.97

816 0.17 0.21 0.34 0.48 0.83 1.38

Notes: (a) permissible but not recommended for prolonged use above 425°C(d) not to be used over 343°C(f) not to be used over 425°C(g) not to be used over 455°C(h) not to be used over 540°C

Additional Notes: (1) Upon prolonged exposure to temperatures above about 800°F (425°C), the carbide phase of carbon steel may be converted to graphite

(3) Only killed steel shall be used above 455°C(5) At temperatures over 540°C, use only when the carbon content is 0.04 percent or higher(6) For temperatures above 540°C, use only if the material is heat treated by heating it to a temp-

erature of at least 1040°C and quenching in water or rapidly cooling by other means

FIG. 17-28

Pressure-Temperature Ratings for Pipe Flanges and Flanged Fittings from ANSI B16.5-1981

17-27

REFERENCES

1. “Fluid Mechanics” by N. DeNevers, Addison-Wesley, Reading,

Mass., 1970, p. 127.

2. “Experimental Research on the Flow of Water in Pipes” by H.

Darcy, Mem. Acad. Sci. Inst. Imp. Fr., Vol. 15, 1858, p. 141 (in

French), “Mechanics of Engineering” by J. Weisbach, Van Nos-

trand, 1872 (translated from German).

3. “Friction Factors for Pipe Flow” by L. Moody, Trans ASME 66,

1944.

4. C.F. Colebrook, “Turbulent Flow in Pipes with Particular Refer-

ence to the Transition Region Between the Smooth and Rough

Pipe Law,” J. Inst. Civil Engineers, London, 1939.

5. “Flow of Fluids through Valves, Fittings and Pipe,” by the Crane

Co., Chicago, Technical Paper No. 410, 1988.

6. “Steady Flow in Gas Pipelines,” American Gas Association, IGT

Technical Report 10, Chicago, 1965.

7. T.R. Weymouth, Transactions of the American Society of Me-

chanical Engineers, Vol. 34, 1912.

8. F.F. Richardson of Foreman-Richardson-Baird, The Petroleum

Engineer, July, 1945.

9. F.N. Oliphant, “Production of Natural Gas,” Report of USGS,

1902.

10. “Fluid Flow, Pumps, Pipes and Channels” by N. Cheremisinoff,

Ann Arbor Science, Ann Arbor, Michigan, 1981, p. 184.

11. Piping Handbook, Sabin Crocker, McGraw-Hill Publishing Co.,

Inc., 1945.

12. Mandhane, J.M., G.A. Gregory, and K. Aziz. “A Flow Pattern Map

for Gas-Liquid Flow in Horizontal Pipes” Int. J. Multiphase Flow,

Pergamon Press, Vol. 1, 1974, pp. 537-553.

13. Taitel, Yehuda, and A.E. Dukler. “A Model for Predicting Flow

Regime Transitions in Horizontal and Near Horizontal Gas-Liq-

uid Flow” AIChE Journal, Vol. 22, No. 1, Jan. 1976, pp. 47-55.

14. Aziz, K., G.W. Govier, and M. Fogarasi. “Pressure Drop in Wells

Producing Oil and Gas” J. Cdn. Pet. Tech., July-Sept 1972, pp.

38-48.

15. Lockhart, R.W., and R.C. Martinelli, “Proposed Correlation of

Data for Isothermal Two-Phase, Two-Component Flow in Pipes”

Chemical Engineering Progress, Vol. 45, No. 1, January 1949, pp.

39-48.

16. Beggs, H. Dale, and James P. Brill. “A Study of Two-Phase Flow

in Inclined Pipes” Trans. AIME, May 1973, pp. 606-617.

17. Orkiszewski, J. “Predicting Two-Phase Pressure Drops in Verti-

cal Pipe” J. Pet. Tech, AIME, June 1967, pp. 829-838.

18. Baker, O., et al. “Gas-Liquid Flow in Pipelines, II. Design Man-

ual” AGA-API Project NX-28, October 1970.

19. Dukler, A.E., Moye Wicks, III, and R.G. Cleveland. “Frictional

Pressure Drop in Two-Phase Flow: B. An Approach through Simi-

larity Analysis” AIChE Journal, Vol. 10, No. 1, January 1964, pp.

44-51.

20. Flanigan, Orin. “Effect of Uphill Flow on Pressure Drop in Design

of Two-Phase Gathering Systems” Oil and Gas Journal, March

10, 1958, pp. 132-141.

21. Eaton, Ben A., et al. “The Prediction of Flow Patterns, Liquid

Holdup and Pressure Losses Occurring During Continuous Two-

Phase Flow in Horizontal Pipelines” J. Pet. Tech. AIME, June

1967, pp. 815-828.

22. Greskovich, Eugene J., and Adam L. Shrier. “Slug Frequency in

Horizontal Gas-Liquid Slug Flow” Ind. Eng. Chem. Process De-

velop., Vol. 11, No. 2, 1972, pp. 317-318.

23. Brill, James P., et al. “Analysis of Two-Phase Tests in Large Di-

ameter Prudhoe Bay Flowlines” SPE 8305, AIME, 1979.

24. Schmidt, Zelmir, and James P. Brill. “Experimental Study of Se-

vere Slugging in a Two-Phase Flow Pipeline-Riser System” SPE

8306 AIME, 1979.

25. Cunliffe, R.S. “Condensate Flow in Wet Gas Lines can be pre-

dicted” Oil and Gas Journal, October 30, 1978, pp. 100-108.

26. McDonald, Alvis E., and Ovid Baker. “Multiphase Flow in Pipe-

lines” Oil and Gas Journal, June 15, June 22, June 29, and July

6, 1964

27. Manual of Petroleum Measurement, Chapter 14.3, Orifice Me-

tering of Natural Gas and Other Related Hydrocarbon Fluids,

Second Edition, September, 1985 (AGA Report #3)(GPA 8185-85)

(ANSI/API 2530).

28. Chemical Plant and Petroleum Refinery Piping, ANSI/ASME

B31.3.

29. Gas Transmission and Distribution Piping Systems,

ANSI/ASME B31.8.

BIBLIOGRAPHY

1. R.W. Leach & W.P. Redmond, “How a Computer is Applied to a

Specific Problem in Pipeline Design,” Oil & Gas Journal, Flow

Calculations in Pipelining, 1960.

2. Wilson, McAdams & Seltzer, “Flow of Fluids Through Commer-

cial Pipelines,” Journal of Industrial and Engineering Chemistry,

February, 1922.

3. T.R. Aude, “Suggested Formula for Calculating Capacity of Prod-

ucts Pipe Lines,” 1943.

4. Wilson & McAdams, “Contribution No. 19" from the Department

of Chemical Engineering, Massachusetts Institute of Technology.

5. W.G. Heltzel, “Fluid Flow and Friction in Pipelines,” Oil & Gas

Journal, June 5, 1930.

6. T.R. Young, “Digital Simulation of Crude Oil Pipelines,” API Pipe-

line report, May 2, 1960.

17-28