004_Stress Analysis Report

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SAUDI ARABIAN OIL COMPANY

DOCUMENT TITLE

STRESSS ANALYSIS REPORT FOR ABQQ-266 & 316 FLOWLINES

PROJECT NAME

ABQQ-266 & 316 (OIL) F/L C/S REPLACEMENT W/ RTR

PREPARED BY

FIBER GLASS SYSTEMS Rev. No.

Date Description Prepared

by

Checked

by

Approved by

PI Cons ARAMCO

0 10/08/2010 Issued for Review AVE RH

This document has been prepared for the titled project or named part thereof and should not be relied upon or used for any other project without an independent check being carried out as to its suitability and prior written authority of WPOE being obtained. WPOE accepts no responsibility or liability for the consequences of this document being used for a purpose other than the purposes for which it was commissioned. Any person using or relying on the document for such other purpose agrees, and will by such use or reliance be taken to confirm his agreement to indemnify WPOE for all loss or damage.

Sheet A

PROJECT : Abqaiq flowlines

UNIT : ABQQ-266 & ABQQ-316 0

CLIENT : Aramco

ATTACHED REFERENCE DOCUMENTS

1.

2.

3.

ATTACHMENT "A" :

REV. DATE DESCRIPTION CHECKED APPROVED

REVISED SHEETS ONLY ISSUED ENTIRE DOCUMENT ISSUED TOTAL NUMBER OF SHEETS572

AvE

11/08/10

issued for approval

PREPARED

AvE GF0 11/08/10

STRESS ANALYSIS REPORT

JOB No. :

REV./DATE

DOC .No. : 273-SRP-01DFP-273

O:\FORMS\ENG\GB03 24.01.97

Dynaflow International Inc. Static Stress Analysis

Report No. 273-SRP-01, Rev. 0 Issue date: 11-08-2010

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Contents

1. Introduction ............................................................................................................... 3

2. Data used ................................................................................................................... 4

2.1 Design conditions ................................................................................................................................ 4 2.2 Material properties ............................................................................................................................... 4 2.4 Pipe content weight ............................................................................................................................. 5

3. Analysis ..................................................................................................................... 6

3.1 Static analysis ...................................................................................................................................... 6 3.2 Boundary conditions & Assumptions ................................................................................................... 6

4. Results & Recommendations ................................................................................... 7

5. Conclusions ............................................................................................................... 8

Appendix 1 – Stress Model ABQQ-266B – Reference drawings ................. (4 pages)

Appendix 2 – Stress Model ABQQ-266B – Input Listing ............................ (56 pages)

Appendix 3 – Stress Model ABQQ-266B – Analysis results

Appendix 3a – Displacements .................................................................................................... (30 pages) Appendix 3b – Stresses in GRE piping .................................................................................... (195 pages) Appendix 3c – Stresses in steel piping ....................................................................................... (14 pages) Appendix 3d – Loads on anchors ................................................................................................. (3 pages)

Appendix 4 – Stress Model ABQQ-316B – Reference drawings ................. (4 pages)

Appendix 5 – Stress Model ABQQ-316B – Input Listing ............................ (46 pages)

Appendix 6 – Stress Model ABQQ-316B – Analysis results

Appendix 6a – Displacements .................................................................................................... (26 pages) Appendix 6b – Stresses in GRE piping .................................................................................... (163 pages) Appendix 6c – Stresses in steel piping ....................................................................................... (14 pages) Appendix 6d – Loads on anchors ................................................................................................. (3 pages)



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1. Introduction

In this report the static stress analysis results are presented for the 6” and 8” GRE flow lines from wells

ABQQ-266 and ABQQ-316 at the Abqaiq field. The lines are fully underground. The length of each of the

lines is approximately 620 m. The CAESAR II v.5.2 pipe stress analysis software has been used for

modeling and analysis. The system has been analyzed conform the rules of ISO-14692. Pipe stresses

have been assessed using the allowable stress envelope for the applicable material. The pipe

manufacturer, M/s Fiber Glass Systems, has provided data for the construction of the stress envelope.

This report is based on the following drawings:

Drawing No. revision

BB-544591 sheet 001 A

BB-544591 sheet 002 A

BB-429910 sheet 001 A

BB-429910 sheet 002 A

Input and output data have been attached in the appendices. The following has been provided:

1) Marked-up copy of drawings showing node numbers used in the analysis (only the most

important node numbers have been indicated. Marking all node numbers would make the

illegible).

2) Computer input listing.

3) Analysis results comprising of :

a. Displacements of each node.

b. Stresses at each node.

c. Stress envelope indicating highest stress for each load case.

d. Loads on anchors at start and end of flow lines.



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2. Data used The following data has been used for stress calculations:

2.1 Design conditions

Design pressure: pdesign = 93.1 barg

Hydrotest pressure: ptest = 139.5 barg

Max. design temperature: Tmax = 93 °C

Min. design temperature: Tmin = 5 °C

Installation temperature: Tinst = 21 °C

2.2 Material properties

Material: GRE by M/s Fiber Glass Systems

Structural wall thickness: ND 150 10.3 mm ,

ND 200 14.0 mm

Elasticity modulus: Eaxial = 17030 MPa

Ehoop = 28131 MPa

Shear modulus: G = 11000 MPa

Poisson ratio: νhoop/axial = 0.6 (hoop load)

νaxial/hoop = 0.36 (axial load)

Thermal expansion coeff. α = 15.7*10-6

mm/mm/°C

Specific gravity γ = 1.85

Allowable Stresses

The following data has been used to construct the allowable stress envelope:

DN 150:

Qualified stress jqs = 116.6 MPa

Axial strength at zero pressure Ssa(0:1) = 68.9 MPa

Hoop strength at 2:1 pressure condition Ssh(2:1) = 247.9 MPa

DN 200:

Qualified stress jqs = 116.1 MPa

Axial strength at zero pressure Ssa(0:1) = 68.9 MPa

Hoop strength at 2:1 pressure condition Ssh(2:1) = 221.3 MPa



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Part factor f2 f2 = 0.67 (sustained)

f2 = 0.83 (operating / design)

f2 = 0.89 (hydrostatic test / occasional)

2.4 Pipe content weight

Pipe content density (wet crude) ρ = 800 kg/m3



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3. Analysis

3.1 Static analysis

Based on the design conditions, in the static analysis, the following basic load cases have been

considered:

Load case 1 Design [liquid filled pipe weight (W) + design temperature (T1) + design pressure (P1)]

Load case 2 Design [liquid filled pipe weight (W) + design temperature (T2) + design pressure (P1)]

Load case 3 Sustained [liquid filled pipe weight (W) + design pressure (P1)]

Load case 4 Hydrotest [liquid filled pipe weight (W) + hydrotest pressure (P2)]

Where,

Maximum design temperature, T1 = 93 ºC

Minimum design temperature, T2 = 5 ºC

Design pressure, P1 = 93.1 barg

Hydrotest pressure, P2 = 139.5 barg

3.2 Boundary conditions & Assumptions

The models have been terminated at the anchors located at the start and end of the lines. The short

section of steel pipe between the GRE and the anchor has been included in the model.



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4. Results & Recommendations The results of the calculations are attached in the appendices. The computer results show that stresses for all

loadcases are within allowable limits.

The anchors at the start and end of the lines should be designed for the following axial loads (loads in other

directions are negligible):

DN 150: 130 kN

DN 200: 250 kN

The above-listed forces are unfactored.

It is recommended to fully backfill the lines before hydrotesting. Only joints should be left exposed.

The table below summarizes the maximum calculated stresses for each model and load case:

Model Load case Node Axial Stress

(MPa) Hoop Stress

(MPa) Code Stress

(MPa)

Percentage Allowable

(%)

ABQQ-266

OPE 1 234 9.2 67.4 67.4 70.0

OPE 2 22 29.4 67.4 67.4 60.0

SUS 344 25.8 67.4 67.4 86.7

OCC 344 38.5 101.0 101.0 97.7

Model Load case Node Axial Stress

(MPa) Hoop Stress

(MPa) Code Stress

(MPa)

Percentage Allowable

(%)

ABQQ-316

OPE 1 250 9.4 67.8 67.8 70.4

OPE 2 464 29.9 67.8 29.9 71.6

SUS 250 25.7 67.8 67.8 87.2

OCC 280 38.5 101.6 101.6 98.3

The above-listed maximum stresses are plotted on the allowable stress envelopes attached in appendix 3

and 6. It is clear from the graphs that stresses are within allowable limits for all load cases.



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5. Conclusions It may be concluded from the computer results that, upon implementation of the recommendations as

mentioned in section 4:

1. Static pipe stresses are acceptable.

2. It is recommended to fully backfill the lines before hydrotesting. Only joints should be left exposed.

3. The anchors on the DN 150 flow line should be design for an axial force of 130 kN. The anchors on

the DN 200 flow line should be designed for an axial force of 250 kN.



Appendix 1 – Stress Model ABQQ-266B – Reference drawings



Appendix 2 – Stress Model ABQQ-266B – Input Listing

004_Stress Analysis Report

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