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SINGA GAS

DEVELOPMENT PROJECT

SALES GAS PIPELINE STRESS ANALYSISJob No. : 07001 1 of 13

Doc. No. : SGA – L – CC – 50 – 002

CLIENT : MEDCO E & P LEMATANG

PROJECT TITLE : SINGA GAS DEVELOPMENT PROJECT

LOCATION : LEMATANG BLOCK, SOUTH SUMATERA

1 31-Mar-09 Issued for Approval

0 25-Aug-08 Issued for Review ASW SFL BHK

REV. NO. DATE DESCRIPTION PREP’D CHK’D APP’D

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Doc. No. : SGA – L – CC – 50 – 002

REVISION CONTROL SHEET

REV. NO DATE DESCRIPTION

0 25-Aug-08 Issued for Review

1 31-Mar-09 Issued for Approval

Based on Transmittal No. SGA-T-IJKL-00030

IKPT Comment

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Doc. No. : SGA – L – CC – 50 – 002

TABLE OF CONTENTS

1. INTRODUCTION 4

2. SCOPE 4

3. DEFINITIONS 4

4. ENVIRONMENTAL CONDITIONS 4

5. REFERENCE 5

6. DESIGN BASIS AND PIPELINE CHARACTERISTICS 5

7. DESCRIPTION OF LOAD CASES 7

8. PIPING SUPPORTS 8

9. STRESS ANALYSIS REPORT 9

ATTACHMENT

APPENDIX-1 COMPUTER PLOT AND STRESS ISOMETRICAPPENDIX-2 INPUT FILEAPPENDIX-3 STRESS RESULTAPPENDIX-4 RESTRAIN SUMMARYAPPENDIX-5 DISPLACEMENT REPORT

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1. INTRODUCTION

This document provides the report of Stress Analysis at critical area long of onshore Sales Gas Pipeline required for SINGA field in Lematang Block South Sumatera operated by Contractor, hereinafter referred as COMPANY.

The result of this Stress Analysis document will be used for pipe stress analysis.

2. SCOPE

This document provided modeling for stress and flexibility calculation for above ground & buried/underground pipeline section in Lematang South Sumatera for SINGA GAS DEVELOPMENT PROJECT. Flexibility stress analysis of the pipeline has been performed to achieve the followings:

To ensure that the above ground piping stress are within the allowable limit as per design code ASME B31.8

To make a sure that the under ground pipeline stress are within the allowable limit as per design code ASME B 31.8

To locate the special pipe supports requirement (if any) Optimize the pipe support location and the piping load on to the support To determine the anchor loads at both ends of the above ground piping

stress

3. DEFINITIONS

Within the contents of this Stress Analysis Procedure :

“COMPANY” means PT Medco E&P Lematang.“CONTRACTOR” means IKPT who is specifying/purchasing the equipment materials and services for and on behalf of the COMPANY”.

The “SUBCONTRACTOR” means PT. Kelsri, who has been subcontracted to perform the detailed engineering of Sales Gas Pipeline.

“CERTIFICATION AGENCY” is “Third Party Inspection Agency” appointed by PT Medco E&P Lematang

.4. ENVIRONMENTAL CONDITIONS

The climate is tropical monsoon, which is characterized by hot and humid condition throughout the year. There are two distinct seasons, the dry season and rainy season. The rainy season occurs from November to May and the dry season occurs from June to October.

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Doc. No. : SGA – L – CC – 50 – 002

1. Temperature

2. Ambient Temperature

a. Maximum

b. Minimum

c. Average

3. Relative Humidity

a. Maximum

b. Minimum

c. Average

4. Soil Resistivity / Characteristics

5. REFERENCE

API 5L American Petroleum InstituteSpecification for Linepipe

ASME American Society of Mechanical EngineersB 31.8 Gas Transmission and Distribution Piping Systems

ANSI American National Standard Institute B16.9Factory-Made Wrought Steel Butt welding Fittings

SGA-G-GL-00-001 Engineering Design Basis

SGA-L-ES-00-002 Pipeline Data

6. DESIGN BASIS AND PIPELINE CHARACTERISTICS

To Perform Stress Analysis of pipeline should be prepared list of pipe characteristic and soil characteristics which is as follow :

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PIPE CHARACTERISTICS

Descriptions Unit Value

Design Pressure (P1) Psig 1330

Operating Pressure (P2) Psig 1050

Maximum Operating Pressure (mop) Psig 1194

Hydrotest Pressure (P3) Psig 1672 (1.4 x mop)

Design Temperature (T1) oF 170

Operating Temperature (T2) oF 120

Hydrotest Temperature (T3) oF 80

Avg. ambient temperature oF 80

Avg. Relative humidity % 83

Design life year Min 20

Design Factor - 0.5

Corrosion allowance inch 0.125

Resistivity of Soil Ohm-meter 0.35

Avg Ambient Soil Temperature (normal)

oF 70

Weight of Content/Density t/m3 0.97-1.98

SOIL CHARACTERISTICSRev 1

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Descriptions Unit Value

Friction Coefficient Kg/cm 0.13 – 1.22

Soil Density t/m3 0.97 – 1.98

Burried Depth to Top of Pipe m 1.5

Friction Angle deg 1.1-17.2

Undrained Shear Strength Kg/cm2 0.43-1.87

7.DESCRIPTION OF LOAD CASES

7.1 Elementary Load Cases

Elementary load cases chosen as follows:

Thermal in Design Condition (T1)

Thermal in Service Condition (T2)

7.2 Combination Load Cases

Load combinations adopted for stress analysis of the piping line are as follows:

Sustained in Design Conditions (W+P1)

Sustained in Operating Conditions (W+P2)

Design Condition (W+T1+P1)

Service Condition (W+T2+P2)

7.3 Hydrotest

Load case for Hydrotest can be given as follow :

Sustain load (W + P3)

Operating load (W + T3 + P3)

Note :

W : Full weight

P1 : Design Pressure

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P2 : Operating Pressure

P3 : Hydrotest Pressure

T1 : Design Temperature

T2 : Operating Temperature

T3 : Water Temperature

7.4 Stress Limit Criterion

Stress constraints and limit are defined as follows:

SL : calculated stress for sustained loads

SE : calculated stress for thermal loads

Sy : Yield strength at ambient temperature

Slp : Longitudinal stress due to internal pressure

SB : Nominal bending stress in straight pipe

St : Longitudinal stress due to thermal expansion

SE + SL < Syield (OPE)

SL = Slp+SB < 0.75 Sy (SUS)

SE = sqrt (SB^2 + 4St^2) < 0.72 Sy (EXP)

7.5 Flange Leakage Check

7.6 Anchor Block

8. PIPING SUPPORTS

8.1 General

This section presents the type of piping supports to be used to keep the line system stress within the allowable limit and the summary of piping loads.

8.2 General Supports

The number and location of supports have been chosen to satisfy static free span requirement. Fix type and guide of support attached to the piping system is chosen to compensate elongation due to combined load both of design, operating and test condition.

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Doc. No. : SGA – L – CC – 50 – 002

9. STRESS ANALYSIS REPORT

Toward to the pipeline, after the pig launcher area, before and after the LBCV at Kp. 16+000 & Kp. 32+000, and before the pig receiver, the pipes are buried to the ground. Due to temperature changes and pressure, buried pipe deforms laterally in areas immidiately adjacent to changes in directions (bends). In areas far from bends, the deformation is primarily axial.

Stress analysis of the piping has been carried out using a non linear computer program Caesar II Version 4.2. The pipeline has been modeled from pipeline anchor block area between buried pipe and above ground pipeline (at surface of the ground). Both the ends of above ground pipeline are anchored. Initially the number and the location of supports were chosen to satisfy the free span requirement. Environmental loads are ignored for static stress analysis.

Stress analysis is performed for different load cases defined in section 7.0 and found that the system stresses are within the allowable limit as per ASME B 31.8. The result summary of stresses has been presented in Table 9.1.1. until Table 9.3.2. Computer plot and the stress isometric have been presented in Attachment-1.

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Table 9.1.1. Summary of maximum stresses as per ASME B 31.8 at Pig Launcher (Above Ground) – Burried Pipe Sales Gas Pipeline

Load CaseLoad Case No.

@Node No.

Stress (Psi)Allowable Stress (Psi) Ratio

(%)SL SE Sy

SUS 1 (W+P1)

1 25 11143.6 45000 - - 24.76

SUS 2 (W+P2)

2 25 9153.0 45000 - - 20.34

SUS 3 (W+P3)

3 25 13574.9 45000 - - 30.17

EXP (T1) 4 70 137.7 - 43200 - 0.32

EXP (T2) 5 70 109.3 - 43200 - 0.25

OPE (W+T1+P1)

6 25 11013.3 - - 60000 18.36

OPE (W+T2+P1)

7 25 11040.1 - - 60000 18.40

OPE (W+T3+P3)

8 25 13562.3 - - 60000 22.60

Table 9.1.2. From calculated stress Pig Launcher – Burried Pipe SGP, the maximum operational condition load at Anchor Block will be given as follow:

Load Case @NodeForces (lb)

Fx Fy Fz

OPE (W+T1+P1) 70 -166 -278 -16

Table 9.1.3. From calculated stress Pig Launcher – Burried Pipe SGP, the maximum displacement report will be given as follow:

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Load Case @NodeTranslation (in) Rotation (deg)

Dx Dy Dz Rx Ry Rz

OPE (W+T1+P1) 8 -0.55 -0.02 0 0 0 0.012

Table 9.2.1. Summary of maximum stresses as per ASME B 31.8 at LBCV Kp. 16+000 and LBCV Kp. 32+000


@Node No.


(%)SL SE Sy

SUS 1 (W+P1)

1 120 12376.6 45000 - - 27.50

SUS 2 (W+P2)

2120

10386.0 45000 - - 23.08

SUS 3 (W+P3)

3120

14807.9 45000 - - 32.91

EXP (T1) 4120

16087.0 - 43200 - 37.24

EXP (T2) 5120

7884.0 - 43200 - 18.25

OPE (W+T1+P1)

6120

25874.9 - - 60000 43.12

OPE (W+T2+P1)

7120

18991.9 - - 60000 31.65

OPE (W+T3+P3)

7120

16111.8 - - 60000 26.85

Table 9.2.2. From calculated stress LBCV 16+000 & 32+000 SGP, the maximum operational condition load at Anchor Block will be given as follow:

Load Case @Node Forces (lb) Condition

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Fx Fy Fz

OPE (W+T1+P1) 30 -41530 -6313 0 Design

OPE (W+T2+P1) 30 -20690 -3180 0 Operation

OPE (W+T3+P3) 30 -4607 -762 0 Hydrotest

Table 9.2.3. From calculated stress LBCV 16+000 & 32+000 SGP, the maximum displacement report will be given as follow:


Dx Dy Dz Rx Ry Rz

OPE (W+T1+P1) 109 -0.14 -0.87 0 0 0 0.018

Table 9.3.1. Summary of maximum stresses as per ASME B 31.8 at Burried Pipe - Pig Receiver (Above Ground) SGP


@Node No.


(%)SL SE Sy

SUS 1 (W+P1)

1 80 11378.5 45000 - - 25.29

SUS 2 (W+P2)

2 80 9387.9 45000 - - 20.86

SUS 3 (W+P3)

3 80 13809.9 45000 - - 30.69

EXP (T1) 4 50 4515.5 - 43200 - 10.45

EXP (T2) 5 50 3583.8 - 43200 - 8.30

OPE (W+T1+P1)

6 50 13506.3 - - 60000 22.51

OPE (W+T2+P1)

7 50 12670.4 - - 60000 21.12

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Doc. No. : SGA – L – CC – 50 – 002

OPE (W+T3+P3)

8 50 13789.5 - - 60000 22.98

Table 9.3.2. From calculated stress Burried Pipe - Pig Receiver (Above Ground) SGP, the maximum operational condition load at Anchor Block will be given as follow:

Load Case @NodeForces (lb)

Fx Fy Fz

OPE (W+T1+P1) 50 1354 -97 6408

Table 9.3.3. From calculated stress LBCV 16+000 & 32+000 SGP, the maximum displacement report will be given as follow:


Dx Dy Dz Rx Ry Rz

OPE (W+T1+P1) 2 -0.68 0 0 0 0 0

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