Zetkin Wall Thickness Calculations

7/30/2019 Zetkin Wall Thickness Calculations

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CALCULATION TABLE OF CONTENTSDOCUMENT No : P09QGC02-000-CAL-L-002

PROJECT / JOB TITLE : QCLNG E05 Pipeline QGC Doc No: QCLNG-BG00-PLE-CAL-000002

CLIENT : Queensland Gas Company JOB No. P09QGC02

Sheet 2 of 23CALCULATION TITLE: Pipe Wall Thickness Calculations to AS2885.1

Calculations

page

1 Wall thickness Calculation for Design internal pressure 3

2 Road Crossing Calculation - 1200mm Cover 4-6

3 Road Crossing Calculation - 1500mm Cover 7-9

4 Road Crossing Calculation - State Controlled Crossing 1200mm Cover 10-12

5 Road Crossing Calculation - State Controlled Crossing 1500mm Cover 13-15

6 Road Crossing Calculation - Unformed infrequent use 16-18

7 Resistance to Penetration Calculation 19

8 Pipe Ovality 20

9 Wall thickness Summary 20

10 Wall thickness Calculation for Design internal pressure of bends 2111 Buoyancy of Pipe 22

12 Permissible External Pressure 23

Attachments

1 American Lifelines Alliance: Guidelines for the design of Buried 34 pages

Steel Pipe, July 2001. Sections 1-6

2 Density of soils: Marks' Standard Handbook for Mechanical 1

Engineers, 8th Ed, pg 6-8

G

G


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CALCULATIONDOCUMENT No : P09QGC02-000-CAL-L-002



Sheet 3 of 23

CALCULATION TITLE: Pipe Wall Thickness Calculations to AS2885.1

1. Required Wall thickness Calculations as per AS2285.1

Design Pressure PD = 10.2 MPa

Nominal Pipe Outside Diameter D = 1067 mm

Design Factors FD = 0.8 Below Ground Pipe - Option 1

FD = 0.72 Below Ground Pipe - Option 2

FD = 0.67 Pipeline Assemblies - Above ground Pipe

Design Temperature (Below Ground Pipe) Td1 = 65oC

Design Temperature (Above Ground Pipe) Td2 = 85oC > 65

oC therefore derate of yield strength

required as per AS2885.1 3.4.3

Below Ground Piping:Specified Min Yield Strength API5L X70 YX70 = 485 MPa API5L - 2007 Standard Table 7

Specified Min Yield Strength API5L X80 YX80 = 555 MPa API5L - 2007 Standard Table 7

Above ground Piping

Reduction in yield = 0.07%/oC by which the design temperature exceeds 23

oC

therefore reduction in yield = 4.34 %

Specified Min Yield Strength API5L X70 YX70 = 463.95 MPa

Specified Min Yield Strength API5L X80 YX80 = 530.91 MPa

1.1. Wall Thickness for design internal pressure (tp) AS2285.1 section 5.4.3

equation 5.4.3

For Design Factor FD=0.8 (Below Ground Pipe):

Wall thickness for design internal pressure for API5L X70 tpX70 = 14.03 mm


For Design Factor FD=0.72 (Below Ground Pipe):



For Design Factor FD=0.67 (pipeline assembly sections - Above Ground Pipe) :



Summary - Calculated wall thickness requirements for internal pressure:

Grade FD

Nominal

Thickness (mm)

API5L X70 0.80 14.10

API5L X70 0.72 15.60

API5L X70 0.67 17.60

API5L X80 0.80 12.30

API5L X80 0.72 13.70

API5L X80 0.67 15.30

YD

Dp

F

DPt2

=


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CLIENT : Queensland Gas Company JOB No. P09QGC02Sheet 4 of 23


2. Road Crossings as per AS2885.1 Clause 5.7.3 and API RP 1102 Section 4.

All road crossing except for state controlled road crossings, ie council controlled, maintained access roads crossings.





Pipe Wall Thickness for API5L X70 pipe twX70 = 18.00 mm (min required)

Pipe Wall Thickness for API5L X80 pipe twX80 = 15.20 mm (min required)

Temperature Derating Factor T = 1 AS2885.1 Section 3.4.3, T


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2.3 Cyclic Stresses API RP 1102 4.7.2.2.4.1

The cyclic circumferential stress due to highway vehicular load: (5)

Highway stiffness factor cyclic circumferential stress API5L X70 KHhX70 = 20.4 (figure 14)


Highway geometry factor for circumferential stress GHh = 0.95 (figure 15)

Highway pavement factor R = 1.1 Table 2 (Tandem axle no pavement)

Highway axle configuration factor L = 1 Table 2 (Tandem axle)

Impact Factor Fi = 1.18 (1+DLA)

Cyclic circumferential stress for API5L X70 SHhX70 = 18.87 MPa


The cyclic longitudinal stress due to Highway vehicular load: (6)

Highway stiffness factor cyclic longitudinal stress API5L X70 KLhX70 = 15 (figure 16)

Highway stiffness factor cyclic longitudinal stress API5L X80 KLhX80 = 15.1 (figure 16)

Highway geometry factor for longitudinal stress GLh = 0.77 (figure 17)

Highway pavement factor R = 1.1 Table 2

Highway axle configuration factor L = 1 Table 2


Cyclic longitudinal stress for API5L X70 SLhX70 = 11.24 MPa

Cyclic Longitudinal stress for API5L X80 SLhX80 = 11.32 MPa

Cyclic stress due to internal pressure: (7)

Cyclic stress due to internal pressure API5L X70: SHiX70 = 297.22 MPa


2.4 Principal Stresses S1,S2,S3 API RP 1102 4.8.1.2

Maximum circumferential Stress: (9)

Maximum circumferential Stress API5L X70: S1X70 = 342.20 MPa


wRLFGKS iLhLhLh =

( )

w

w

Hit

tDpS

2

=

HiHhHe SSSS ++=1

wRLFGKS iHhHhHh =


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Sheet 6 of 23


2.4 Principal Stresses S1,S2,S3 Cont..

Maximum Longitudinal Stress: (10)

Youngs Modulus of steel ES = 201138 MPa @55oC B31.3 Table C-6

Coefficient of thermal expansion T = 0.00001108 peroC @55

oC B31.3 Table C-5

Installation temperature T1 = 10oC Min Ground Temp as per BOD

Maximum operating temperature T2 = 55oC Max Gas Temp at CPP outlet

Poisson's Ratio of Steel S = 0.3

Maximum Longitudinal Stress API5L X70: S2X70 = 7.96 MPa


Maximum Radial Stress: S3 = -P = -MAOP (11)

S3 = -10.2 MPa

2.5 Total Effective Stress API RP 1102 4.8.1.3

The total effective stress: (12)

The total effective stress must satisfy : Seff < SMYS x F where F = 0.72 as per AS2885.1 5.7.3 (d)(i)

Total Effective Stress API5L X70 SeffX70 = 343.68 MPa < 349.2 MPa PASS


2.6 Check for Fatigue in Welds API RP 1102 4.8.2.1

Cyclic stress in girth Weld: (14)

Fatigue endurance limit of girth weld SFG = 82740 kPa Table 3

Cyclic longitudinal stress for API5L X70 SLhX70 = 11.24 MPa < 59.57 MPa PASS

Cyclic Longitudinal stress for API5L X80 SLhX80 = 11.32 MPa < 59.57 MPa PASS

Cyclic Stress in longitudinal weld: (20)

Fatigue endurance limit of longitudinal weld SFLX70 = 89635 kPa Table 3 (SAW to be conservat ive)


Cyclic circumferential stress for API5L X70 SHhX70 = 18.87 MPa < 64.54 MPa PASS


( ) ( )HiHeSTSLh SSTTESS ++= 122

( ) ( ) ( )[ ]213

2

32

2

21

2

1SSSSSSSeff ++=

FSS FGLh

FSS FLHh


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Sheet 7 of 23


3. Road Crossings as per AS2885.1 Clause 5.7.3 and API RP 1102 Section 4. - 1500mm Cover

All road crossing except for state controlled road crossings, ie council controlled, maintained access roads crossings.




Pipe Wall Thickness for API5L X70 pipe twX70 = 18.00 mm (Wall thickness selected)



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wRLFGKS iLhLhLh =

( )

w

w

Hit

tDpS

2

=

HiHhHe SSSS ++=1

wRLFGKS iHhHhHh =


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oC B31.3 Table C-5

Installation temperature T1 = 10 C Min Ground Temp as per BOD





S3 = -10.2 MPa













( ) ( ) ( )[ ]213

2

32

2

21

2

1SSSSSSSeff ++=

FSS FGLh

FSS FLHh


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4. Road Crossings as per AS2885.1 Clause 5.7.3 and API RP 1102 Section 4. - State Controlled Road Crossing 1200 mm Cover







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wRLFGKS iLhLhLh =

( )

w

w

Hit

tDpS

2

=

HiHhHe SSSS ++=1

wRLFGKS iHhHhHh =


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oC B31.3 Table C-5




Maximum Longitudinal Stress API5L X70: S2X70 = -16.89 MPa


S3 = -10.2 MPa













( ) ( ) ( )[ ]213

2

32

2

21

2

1SSSSSSSeff ++=

FSS FGLh

FSS FLHh


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5. Road Crossings as per AS2885.1 Clause 5.7.3 and API RP 1102 Section 4. - State Controlled Road Crossing 1500 mm Cover







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wRLFGKS iLhLhLh =

( )

w

w

Hit

tDpS

2

=

HiHhHe SSSS ++=1

wRLFGKS iHhHhHh =


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oC B31.3 Table C-5




Maximum Longitudinal Stress API5L X70: S2X70 = -17.27 MPa


S3 = -10.2 MPa













( ) ( ) ( )[ ]213

2

32

2

21

2

1SSSSSSSeff ++=

FSS FGLh

FSS FLHh


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Sheet 16 of 23


6. Road Crossings as per AS2885.1 Clause 5.7.3 and API RP 1102 Section 4

6.1 Crossing at unformed roads/tracks used infrequently:





Pipe Wall Thickness for API5L X70 pipe twX70 = 14.10 mm Wall thickness (design factor = 0.8)

Pipe Wall Thickness for API5L X80 pipe twX80 = 12.30 mm Wall thickness (design factor = 0.8)



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Highway geometry factor for circumferential stress GHh = 1 (figure 15)







Highway stiffness factor cyclic longitudinal stress API5L X70 KLhX70 = 15.1 (figure 16)







Cyclic Longitudinal stress for API5L X80 SLhX80 = 11.46 MPa








wRLFGKS iLhLhLh =

( )

w

w

Hit

tDpS

2

=

HiHhHe SSSS ++=1

wRLFGKS iHhHhHh =


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Sheet 18 of 23






oC B31.3 Table C-5

Installation temperature T1 = 10oC Min Ground Temp as per BOD






S3 = -10.2 MPa



The total effective stress must satisfy : Seff < SMYS x F where F = 0.9 as per AS2885.1 5.7.3 (d)(i)(B)







Cyclic Longitudinal stress for API5L X80 SLhX80 = 11.46 MPa < 74.47 MPa PASS







( ) ( ) ( )[ ]213

2

32

2

21

2

1SSSSSSSeff ++=

FSS FGLh

FSS FLHh


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Sheet 19 of 23


7. Resistance to penetration Calculation (AS2885.1 Clause 4.11.3)

As per AS2885.1 clause 4.11.3, the effectiveness of resistance to penetration may be determined using calculations as per Appendix M

As per Appendix M, In principle, penetration should not occur if: Rp>BxF (M2)

Where:

Rp is the force required to penetrate the pipe (kN): (M3)

F is the maximum force applied to the pipeline by the machine (kN): (M4)

Factor B as per table M5. B = 1

Pipe wall thickness required for API5L X70 twX70 = 11.60 mm (min required)


Ultimate tensile Strength of API5L X70 UX70= 570 MPa API5L-2007 Table 7

Ultimate tensile Strength of API5L X80 UX80= 625 MPa API5L-2007 Table 7

Based on the excavator tooth dimensions provided in AS2885.1 table M3, the following Rp and Fbucketforces are

calculated for various excavator sizes:

Excavator

Weight (t)L at point W at point RpX70 RpX80 BxF L at point W at point RpX70 RpX80 BxF

5.0 51.0 4.0 327.2 327.7 36.4 6.0 5.0 138.8 139.0 36.4

10.0 56.0 14.0 509.6 510.3 70.5 8.0 7.0 167.0 167.2 70.5

15.0 63.0 13.0 547.4 548.2 102.4 11.0 9.0 197.0 197.3 102.4

20.0 76.0 13.0 630.7 631.6 132.0 13.0 10.0 214.4 214.7 132.0

25.0 89.0 18.0 754.8 755.9 159.4 11.0 17.0 224.3 224.7 159.4

30.0 102.0 21.0 861.2 862.4 184.5 12.0 20.0 236.6 236.9 184.5

35.0 121.0 23.0 1004.0 1005.5 207.4 14.0 22.0 253.5 253.9 207.4

40.0 127.0 24.0 1051.3 1052.9 228.0 16.0 25.0 271.5 271.9 228.0

55.0 143.0 30.0 1191.5 1193.3 276.4 17.0 25.0 278.5 279.0 276.4

As per the table above. The wall thickness calculated for both the X70 and X80 pipe is sufficient to provide resistance to penetration

for excavators up to and including 55t weight using buckets with general purpose, single point penetration or twin pointed tiger teeth.

This applies to areas where penetration resistance can be reasonably relied on to satisfy the requirements of the safety management study

ie where B = 1 or less as per table M5.

For high consequence areas where penetration must never occur:

Factor B as per table M5. B = 1.3



ExcavatorWeight (t)

L at point W at point RpX70 RpX80 BxF L at point W at point RpX70 RpX80 BxF

5.0 51.0 4.0 423.1 423.0 47.3 6.0 5.0 179.5 179.5 47.3

10.0 56.0 14.0 658.9 658.8 91.7 8.0 7.0 215.9 215.9 91.7

15.0 63.0 13.0 707.8 707.7 133.1 11.0 9.0 254.8 254.7 133.1

20.0 76.0 13.0 815.5 815.4 171.6 13.0 10.0 277.2 277.2 171.6

25.0 89.0 18.0 976.0 975.8 207.2 11.0 17.0 290.1 290.0 207.2

30.0 102.0 21.0 1113.6 1113.3 239.9 12.0 20.0 305.9 305.9 239.9

35.0 121.0 23.0 1298.3 1298.1 269.6 14.0 22.0 327.8 327.7 269.6

40.0 127.0 24.0 1359.5 1359.2 296.4 16.0 25.0 351.0 351.0 296.4

55.0 143.0 30.0 1540.7 1540.4 359.3 17.0 25.0 360.2 360.1 359.3

In high consequence areas where penetration must never occur, the wall thickness calculated for the X70 and X80 pipe above are

sufficient to provide resistance to penetration for excavators up to and including 55t weight using buckets with general purpose teeth,

single point penetration or twin pointed tiger teeth.

General Purpose Teeth Single Point penetration tooth and twin pointed tiger teeth

General Purpose Teeth Single Point penetration tooth and twin pointed tiger teeth

( )( )

+

++=

14.34.224100007.0

W

WLtR Uwp

( )2045.05.7 OPOP WWF =


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Sheet 20 of 23


8. Pipe ovality As per Guidelines for the design of Buried Steel Pipe, American Lifelines Alliance. (Appendix 1)

Outside Diameter of Pipe D = 1067 mm

Deflection lag factor Dl = 1.5 4.2.1

Bedding constant K = 0.1 4.2.1

Soil Load on pipe Pv = 0.0142 MPa (Soil Density x Depth. Based on values used in section 2. )

Soil Load on pipe Pv2 = 0.0227 MPa (Soil Density x Depth. Based on values used in section 2. )

Modulus of Soil Reaction E' = 3.4 MPa (Table A-1 Stiff clays, medium dense sands and gravels)

Youngs Modulus of Steel ES = 200500 MPa @65oC

Depth of Soil above pipe C = 750 mm (Worst Case, for traffic crossing at unformed roads)

Depth of Soil above pipe C2 = 1200 mm (Min Depth for crossings at formed roads)

Load at surface (Road Crossings) Ps = 12232 kg (120kN load as per M1600 moving tra ffic. AS2885.1 V4)

Offset Distance from pipe to line of

application of surface load d = 0 mm

External load transmitted to pipe

(4-1)

For unformed roads: Pp = 0.1019 MPa

For formed roads: Pp2 = 0.0398 MPa

Unformed Road: Total load on pipe (Pv + PpF) P = 0.1313 MPa (Where F is impact factor as per table 4.1-2) F = 1.15

Formed Road: Total load on pipe (Pv + PpF) P = 0.0625 MPa (Where F is impact factor as per table 4.1-2) F = 1

Pipe ovality due to earth and live loads:

(4-2) Where R = pipe radius

Note: effects of internal/external lining

have been ignored.

Wall

thickness

(mm)

Area Moment

of inertia (I)

mm4

Ovality (dy/D)

Vertical

Deflection

of pipe (dy)

mm

14.10 233.60 0.038 40.74

15.60 316.37 0.032 33.62

18.00 486.00 0.011 11.77

12.30 155.07 0.048 50.99

13.70 214.28 0.040 42.86

15.30 298.46 0.016 16.62

As per AS2885.1 Section V6, the guideline usually adopted is that deflection of the pipe should not exceed 5% of the pipe diameter. This criteria will be

applied to buried pipe for sections that are not regular road crossings and therefore heavy wall pipe is not used i.e. 0.8 and 0.72 design factor pipe.

Design Criteria for API RP 1102 is based on a maximum vertical deflection of 3% of the vertical diameter. This criteria is applied to the Heavy Wall pipe

that is to be used at all regular road crossings. As per the table above, deflection of ppe is within the allowable limits and therefore ok.

9. Wall thickness Calculation Summary

Pipeline Pipeline

Pipeline

Assemblies Pipeline Pipeline

Pipeline

Assemblies

API5L X70 API5L 70 API5L X70 API5L X80 API5L X80 API5L X80

R1,R2 R1,R2 R1,R2 R1,R2 R1,R2 R1,R2

0.8 0.72 0.67 0.8 0.72 0.67

14.03 15.58 17.51 12.26 13.62 15.30

14.03 15.58 17.51 12.26 13.62 15.30

0.00 0.00 0.00 0.00 0.00 0.00

14.10 15.60 17.60 12.30 13.70 15.30

High

Consequence

Areas and

API5L X70 API5L X80

11.60 11.0011.60

T1,T2,S,I

0.67

15.30

11.00

Material

11.60 15.00

High Consequence Areas

and crossings

T1,T2,S,I

0.67

17.51

thickness for penetration

resistance (mm)

tn (mm) 18.00 15.30

round up round upround up round upround up

Hydrotest and

constructability round up

14.2011.00

15.20N/AN/AN/AN/A 18.00

tw (mm)

Allowances (mm)

round up

N/A

round up

0.00

18.00 15.30

0.00

N/A

X80 FD=0.72 - Soil Load Only

X80 Heavy Wall - Soil and External Loading

Thickness required at

road crossings (mm)



X70 Heavy Wall - Soil and External Loading


Location

FD

tp (mm)

Yes

Yes

Yes

Deflection acceptable

Unformed Road (dy/D < 0.05)

Formed Road (dy/D


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Sheet 21 of 23


10. Wall Thickness for design internal pressure of bends (tp) AS2285.1 section 5.4.4

The minimum wall thickness for design internal pressure of bends shall be determined by:

equation 5.4.4(1)

Where at the extrados of the bend: Where at the intrados of the bend:

Where R = Bend radius at centreline of pipe = 6402 mm (6D)

Wall thickness used in bend manufacture:

API 5L X70 Heavy Wall Pipe tX70 = 18.00

API 5L X80 Heavy Wall Pipe tX80 = 15.30

Material Yield Strength of Bend After Forming:

Min Yield Strength of bend API5L X70 YX70 = 450 MPa (Assumed to be SMYS - 5ksi)

Min Yield Strength of bend API5L X80 YX80 = 520 MPa (Assumed to be SMYS - 5ksi)

Bends may be used above ground therefore de-rate yield strength for above ground temperature:

Min Yield Strength for bend design API5L X70 YX70 = 430.5 MPa

Min Yield Strength for bend design API5L X80 YX80 = 497.4 MPa

mean pipe wall radius for API5L X70 heavy wall pipe rmX70 = 524.50 mm

mean pipe wall radius for API5L X80 heavy wall pipe rmX80 = 525.85 mm

For extrados: FPX70 = 0.96

FPX80 = 0.96

For intrados: FPX70 = 1.04

FPX80 = 1.04

Minimum allowable thickness of bend after forming (FD=0.8 - Above Ground)

Minimum thickness of extrados for API5L X70 tpX70 = 15.20 mm

Minimum thickness of intrados for API5L X70 tpX70 = 16.51 mm

Minimum thickness of extrados for API5L X80 tpX80 = 13.16 mm

Minimum thickness of intrados for API5L X80 tpX80 = 14.29 mm

Actual bend thickness after forming:

Thinning allowance for bend 6.8 % (Based on 6D bend)

Thickness of API5L X70 bend after forming 16.78 mm

Actual design factor of bend 0.75

Thickness of API5L X80 bend after forming 14.26 mm

Actual design factor of bend 0.77

YD

PDp

F

DFPt

2=

( )mm

p rR

rR

F +

+=

2

2

( )mm

p rR

rR

F

= 2

2


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Sheet 22 of 23


11. Buoyancy of Pipe As per Guidelines for the design of Buried Steel Pipe, American Lifelines Alliance Section 6.

Upward force on straight buried pipe from water table being above the pipe is:

Depth of soil cover C = 750 mm Minimum depth of cover

Distance from top of pipe to ground water table hw = 750 mm (Worst Case)

Pipe Density p = 7800 kg/m

Water buoyancy factor RW = 0.67 (3-2, Rw=1-0.33(hw/C))

Dry density of backfill. d = 1600 kg/m (dry sand, gravel,packed, Appendix 2)

Density of Water w = 1000 kg/m

Safety Factor SF = 1.2

Weight of water displaced by bare pipe per meter WW = 1073.0 kg/m Ww = (PI*D2/4)*wxSF

Effective Weight of soil above pipe Ws = 857.9 kg/m Ws = (RwdC)*D

Wall

thickness

(mm)

Weight of

Pipe. Wpkg/m

Buoyancy

force on pipe

FB (kg/m)

Concrete

coating

required?

Concrete

coating

required?

14.10 364 -149 Not Required Yes






Calculate concrete coating thickness required:

Coating

Thickness

(mm)

Weight of

Water

Displaced

by Coated

Pipe (kg/m)

Weight of

Concrete

kg/m

Design

Buoyancy

force on pipe

(kg/m)

Actual

Buoyancy

force on

coated pipe

(kg/m)

154 1782.2 1418 0 -297

147 1744.1 1342 0 -291

135 1683.3 1221 0 -281

163 1828.1 1510 0 -305

156 1792.4 1439 0 -299

148 1751.7 1357 0 -292

Note: Concrete density assumed to be 2400kg/m3

in calculation of required thickness. Thickness calculated by iteration of concrete coating thickness

until design buoyancy force on pipe is zero. The safety factor is applied to the weight of water displaced to ensure sufficient negative buoyancy.

X80 FD=0.8

X80 FD=0.72

X80 Heavy Wall

X70 FD=0.8

X70 FD=0.72

X70 FD=0.8

X70 FD=0.72

X70 Heavy Wall

X80 FD=0.8

X80 FD=0.72

Buoyancy Force on pipe (no

soil cover) (kg/m)

709

671

X70 Heavy Wall

610

755

719

679X80 Heavy Wall

PSWBWWWF =


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Sheet 23 of 23


12. Permitted External Line Pipe Pressure AS2285.1 section 5.4.5

The permitted external pressure shall be determined from the following equation:

equation 5.4.5(1)

Where:

equation 5.4.5(2)

equation 5.4.5(3)

equation 5.4.5(4)

equation 5.4.5(5)


Minimum Pipe Diameter Dmin = 1059.0 mm (At installation = -0.75%D ovality as per pipe spec)

Maximum Pipe Diameter Dmax = 1075.0 mm (At installation = +0.75%D ovality as per pipe spec)

Youngs Modulus of Steel E = 201138 MPa @65oC B31.3 Table C-6

Poisson's ratio = 0.3



tw FD DM fo PP PEL PEXT Equ 5.4.5(1)

(mm) (mm) MPa MPa MPa

X70 FD=0.8 14.1 0.80 1052.90 0.015 10.39 1.06 0.890 0.03

X70 FD=0.72 15.6 0.72 1051.40 0.015 10.36 1.44 1.160 0.03

X70 Heavy Wall 18.0 0.67 1049.00 0.015 11.15 2.23 1.694 0.05

X80 FD=0.8 12.3 0.80 1054.70 0.015 10.36 0.70 0.613 0.02

X80 FD=0.72 13.7 0.72 1053.30 0.015 10.39 0.97 0.823 0.03

X80 Heavy Wall 15.3 0.67 1051.70 0.015 10.82 1.36 1.113 0.03

Note: Iterate PEXT in table above until Equ 5.4.5(1) = 0

The permitted External Pressure (PEXT) on the pipeline is therefore summarised in the table below:

tw PEXT(mm) MPa

X70 FD=0.8 14.1 0.890

X70 FD=0.72 15.6 1.160

X70 Heavy Wall 18.0 1.694

X80 FD=0.8 12.3 0.613

X80 FD=0.72 13.7 0.823

X80 Heavy Wall 15.3 1.113

05.1

12

=+

++ pELEXTEL

w

o

pEXT PPPPt

DfPP

( )

3

21

2

=

M

w

ELD

tEP

=

M

w

yDPD

tFP 2

D

DDfo

minmax

=

wM tDD =


24/59

Zektin Group

407 Royal Parade

Parkville VIC 3052

Ph: (61) 3 8480 1000

Fax: (61) 3 8480 1055



CLIENT : Queensland Gas Company JOB No. P09QGC02Sheet


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Date post:	14-Apr-2018
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Zetkin Wall Thickness Calculations

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