Mapping Corrosion Activities Of Various Concentration Of Acidic Solution In A Pipe Using Ultrasonic Testing.

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‘Saya/Kami akui bahawa telah membaca Karya ini dan pada pandangan saya/kami* karya ini

adalah memadai dari skop dan kualiti untuk tujuan penganugerahan Ijazah Sarjana Muda Kejuruteraan Mekanikal (Struktur dan Bahan)

Tandatangan : ……….

Nama Penyelia I : ……….

Tarikh : ……….

Tandatangan : ……….

Nama Penyelia II : ……….

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MAPPING CORROSION ACTIVITIES OF VARIOUS CONCENTRATION OF ACIDIC SOLUTION IN A PIPE USING ULTRASONIC TESTING

FARAHILDA BINTI MASEKAM

Laporan ini dikemukakan sebagai

memenuhi sebahagian daripada syarat penganugerahan Ijazah Sarjana Muda Kejuruteraan Mekanikal (Struktur dan Bahan)

Fakulti Kejuruteraan Mekanikal Universiti Teknikal Malaysia Melaka

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“I hereby declare that I have read this thesis and in my opinion this thesis is sufficient in

terms of scope and quality for the award of the degree of Bachelor Mechanical

Engineering (Structure & Material)”

Signature : ………..

Name of Supervisor : ………..

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ABSTRACT

Conventional method of inspecting the thickness of pipe due to corrosion is

using Ultrasonic Testing Thickness Measurements (UTTM). This experiment is to study

the corrosion activities in a pipe with using different concentration of acidic.

Hydrochloric acid is used as a medium to create corrosion in internal wall of pipe. The

hydrochloric acid is a strong acid, since it is fully dissociated in water where is a strong

inorganic acid that is used in many industrial processes. The different of concentration

of hydrochloric acid in water, 30%, 50% and 70% are used for this experiment. The

different concentration of acidic used shown distinguishes of corrosion activities on the

internal wall of pipe. The thickness of pipe wall is measured with an Ultrasonic Testing

Thickness Measurement method. The results of corrosion activities are presented in

C-scan presentation resulted from A-C-scan readings obtained from Ultrasonic Testing

Thickness Measurement method. The C-scan result displays are created using the

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ABSTRAK

Ujian Pengukuran Ketebalan Ultrasonik (UTTM) merupakan kaedah yang paling

sesuai untuk memeriksa dan menguji ketebalan paip yang disebabkan oleh kakisan.

Eksperimen ini dijalankan bertujuan untuk mempelajari dan mengetahui aktiviti kakisan

pada paip dengan menggunakan kepekatan asid yang berbeza. Asid hidroklorik

digunakan sebagai medium untuk membentuk kakisaan pada permukaan dalam paip.

Asid ini bersifat kuat dan meluas digunakan di pelbagai proses perindustrian. Pada

eksperimen ini sebanyak tiga jenis kepekatan asid yang berbeza digunakan iaitu 30%,

50% dan 70% kepekatan. Perbezaan kepekatan asid yang digunakan menunjukkna

perbezaan aktiviti kakisan pada bahagian dalam dinding paip. Ketebalan dinding paip

akan diukur dengan menggunakan kaedah Ujian Pengukuran Ketebalan Ultrasonik

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CHAPTER 4 RESULTS AND DISCUSSIONS 44

4.1 MATLAB Programming 44

4.2 Result of 30% Concentration of 46

Hydrochloric Acid

4.5 Result Comparison Between Three 66

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4.6 Advantages of C-scan Display 68

4.7 Factors Influenced the Corrosion Activities 70

CHAPTER 5 CONCLUSION 71

CHAPTER 6 RECOMMENDATION 73

REFERENCES 74

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LIST OF TABLE

NO. TITLE PAGES

1 Properties of Hydrochloric Acid 37

(Source: http://en.wikipedia.org/wiki/Hydrochloric_acid)

2 Physical Properties of Hydrochloric Acid with Different 38

Concentration

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LIST OF FIGURE

NO. TITLE PAGES

1.0 Internal Corrosion on Pipeline 21

(Source: http://www.corrview.com/service_03.htm)

3.1 Project Flow Diagram 31

3.2 Both of End of Pipe Will Welding With Two Lids and Hole 33

to Insert Acidic on Specimen

3.3 Welding Area on Specimen 34

3.4 Dimension of Specimen 34

3.5 Specimen of Experiment 35

3.6 Grid Line on Layout Pipe Surface 35

3.7 Grid Line on a Pipe Surface 36

3.8 Calibration Block K1 (right) and Calibration Block K2 (left) 40

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(Source: Sonix, Inc. “The ABC’s of Ultrasonics Power Point

Presentation”)

3.10 Color Range of Pipe Wall Thickness 43

4.0 Example of C-scan Result Display 46

4.1 First Reading Display Result for 30% Concentration of 46

Hydrochloric Acid

4.2 Second Reading Display Result for 30% Concentration of 47

Hydrochloric Acid

4.3 Third Reading Display Result for 30% Concentration of 47

Hydrochloric Acid

4.4 Forth Reading Display Result for 30% Concentration of 48

Hydrochloric Acid

4.5 Fifth Reading Display Result for 30% Concentration of 49

Hydrochloric Acid

4.6 Sixth Reading Display Result for 30% Concentration of 50

Hydrochloric Acid

4.7 Seventh Reading Display Result for 30% Concentration of 50

Hydrochloric Acid

4.8 Eighth Reading Display Result for 30% Concentration of 51

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4.9 Ninth Reading Display Result for 30% Concentration of 51

Hydrochloric Acid

4.10 Tenth Reading Display Result for 30% Concentration of 52

Hydrochloric Acid

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Hydrochloric Acid

4.29 Ninth Reading Display Result for 70% Concentration of 65

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Hydrochloric Acid

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LIST OF SYMBOLS

h = height, m

r = Radius, m

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LIST OF APPENDIX

NO. TITLE PAGES

A Gantt Chart of PSM I and PSM II 76

B(i) Week 1 Data Reading Initial Thickness of Pipeline Model 78

for 30% Concentration of Hydrochloric Acid

B(ii) Week 2 Data Reading Thickness of Pipeline Model 79

B(iii) Week 3 Data Reading Thickness of Pipeline Model 80

B(iv) Week 4 Data Reading Thickness of Pipeline Model 81

B(v) Week 5 Data Reading Thickness of Pipeline Model 82

B(vi) Week 6 Data Reading Thickness of Pipeline Model 83

B(vii) Week 7 Data Reading Thickness of Pipeline Model 84

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B(viii) Week 8 Data Reading Thickness of Pipeline Model 85

B(ix) Week 9 Data Reading Thickness of Pipeline Model 86

B(x) Week 10 Data Reading Thickness of Pipeline Model 87

C(i) Week 1 Data Reading Initial Thickness of Pipeline Model 88

C(ii) Week 2 Data Reading Thickness of Pipeline Model 89

C(iii) Week 3 Data Reading Thickness of Pipeline Model 90

C(iv) Week 4 Data Reading Thickness of Pipeline Model 91

C(v) Week 5 Data Reading Thickness of Pipeline Model 92

C(vi) Week 6 Data Reading Thickness of Pipeline Model 93

C(vii) Week 7 Data Reading Thickness of Pipeline Model 94

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C(ix) Week 9 Data Reading Thickness of Pipeline Model 96

C(x) Week 10 Data Reading Thickness of Pipeline Model 97

D(i) Week 1 Data Reading Initial Thickness of Pipeline Model 98

D(ii) Week 2 Data Reading Thickness of Pipeline Model 99

D(iii) Week 3 Data Reading Thickness of Pipeline Model 100

D(iv) Week 4 Data Reading Thickness of Pipeline Model 101

D(v) Week 5 Data Reading Thickness of Pipeline Model 102

D(vi) Week 6 Data Reading Thickness of Pipeline Model 103

D(vii) Week 7 Data Reading Thickness of Pipeline Model 104

D(viii) Week 8 Data Reading Thickness of Pipeline Model 105

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D(ix) Week 9 Data Reading Thickness of Pipeline Model 106

for 70% Concentration of hydrochloric Acid

D(x) Week 10 Data Reading Thickness of Pipeline Model 107

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CHAPTER 1

INTRODUCTION

1.1 Project

The purpose of this project is to conduct experiment to study the corrosion

activities in a pipe using various concentration of acidic solution using Ultrasonic

Testing Thickness Measurement (UTTM) method, and to produce a program that

models a C-scan presentation of the corrosion activities in the pipe from A-scan

presentation obtained from UTTM. The study and data collection of this project will be

held at the Universiti Teknikal Malaysia Melaka (UTeM).

1.2 Problem Statement

Corrosion in pipelines is a problem long faced since long time ago. Industrial

sector fields grow older and move to more challenging and often aggressive

environments, the difficulties presented by corrosion are multiplying. Some pipelines

deteriorate slowly, and certain cases pipeline life has been reliably targeted at 70 years

or more. Other pipelines have been built which have exhausted their life after 1 year

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According to Kucera (1988), CO2 and H2S gases, in combination with water,

define most of the corrosion problems in oil and gas production. Other problems include

microbiological activity and the solids accumulation. The mechanisms of CO2 corrosion

are generally well defined. However, the reality inside a pipeline becomes complicated

when CO2 acts in combination with H2S, deposited solids, and other environments. H2S

can be highly corrosive, but can, in some cases, form a protective sulfide scale that

prevents corrosion. Microorganisms can attach to pipe walls and cause corrosion

damage.

On the latest researching by A. Cosham, P. Hopkins, K.A. Macdonald (2007),

corrosion can be classified into one of three general categories. There are internal

corrosion caused by the produced fluids and gases, external corrosion caused by

exposure to groundwater or seawater, and atmospheric corrosion caused by salt spray

and weathering offshore. Of these, internal corrosion is the most costly since internal

mitigation methods cannot be easily maintained and inspected. Pitting corrosion along

the bottom of the pipeline is the primary corrosion mechanism leading to failures in gas

pipelines. The common features of this mechanism are:

a. The presence of water containing any of the following; carbon dioxide (CO2),

bacteria, oxygen (O2), or solids;

b. Pipelines carrying higher levels of free-water production with no means of

water removal, i.e. well site separation or dehydration;

c. The presence of fluid traps where water and solids can accumulate;

d. Vapor phase corrosion is a less common mechanism that has also led to

failures. Although not specifically addressed in this recommended practice,

many of the preventative measures described in this document will also

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[image:22.612.229.460.77.234.2]

Figure 1.0: Internal Corrosion on Pipeline

(Source: http://www.corrview.com/service_03.htm)

On April 2006, in Alaska they had a case about the corrosion in pipelines. On 2nd

March 2006 until April 2006 was determined that 201,000 gallons of oil had spread over

almost 2 acres of tundra. The leaky pipeline remains out of service while field workers

check out corrosion problems. The corrosion on pipelines was detected by the pipeline

leak-detection system sound warnings on four straight days in the week leading up to

last month’s record North Slope oil spill. They found that the 34 inches pipeline that

leaked had circumstances that made leak detection become difficult, which including a

relatively high level of sediment moving through the pipe along with the oil. They also

found the fluctuations in the volume of oil sent was down to the line from a processing

plant can mask a potential leaks. Then the corrosion was blamed for causing an

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1.3 Objectives

The objectives of this study are:

a. To study the corrosion activities in internal pipe using various

concentration of acidic solution.

b. To measure the wall pipe thickness due to corrosion using Ultrasonic

Testing Thickness Measurements (UTTM).

c. To produce a program that models a C-scan presentation of the corrosion

activities in the pipe from A-scan presentation obtained from UTTM

using MATLAB Programming.

1.4 Scope of Study

This study is focused on the internal corrosion in pipelines, where the corrosion

is the main problem since a long time ago. This experiment is to study the corrosion

activities in a pipe with using a different concentration of acid. Then, the thickness of

pipe will be measure with using the Ultrasonic Testing, where every different

concentration of acid affects the different corrosion rate. The acid that is used on this

experiment is a hydrochloric acid (HCl), and the various concentration of acid that will

be used is 30%, 50% and 70% concentration per volume. For one specimen, there have

108 points of thickness need to be measured. The thickness reading taken is doing by

weekly from week one until week ten. The results of corrosion activities will be present

as a program that models a C-scan from A-scan presentation obtained from Ultrasonic

Testing Thickness Measurement (UTTM) method. MATLAB Programming is using to

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CHAPTER 2

LITERATURE REVIEW

2.1 Corrosion in Pipelines

According to A. Cosham, P. Hopkins, K.A. Macdonald (2007), corrosion is an

electrochemical process where it is a time dependent mechanism and depends on the

local environment within or adjacent to the pipeline. Corrosion usually appears as either

general corrosion or localizes (pitting) corrosion. There are many different types of

corrosion, including galvanic corrosion, microbiologically induced corrosion, alternate

current (AC) corrosion, differential soils, differential aeration and cracking. Corrosion

causes metal loss. It can occur on the internal or external surfaces of the pipe, in the base

material, the seam weld, the girth weld, and/or the associated heat affected zone (HAZ).

According to Bolt R and Owen RW (1999), the internal and external corrosion

are together one of the major causes of pipeline failures. Data for onshore gas

transmission pipelines in Western Europe for the period from 1970 to 1997 indicates that

17% of all incidents resulting in a loss of gas were due to corrosion.

On the latest researching by Eiber , Miele and Wilson (2002), incident data from

the Office of Pipeline Safety in the USA for the year 2001 attributes 29% of incidents in

Mapping Corrosion Activities Of Various Concentration Of Acidic Solution In A Pipe Using Ultrasonic Testing.

MAPPING CORROSION ACTIVITIES OF VARIOUS CONCENTRATION OF ACIDIC SOLUTION IN A PIPE USING ULTRASONIC TESTING

ABSTRACT

ABSTRAK

CONTENTS

CHAPTER 1 INTRODUCTION 19

CHAPTER 4 RESULTS AND DISCUSSIONS 44

REFERENCES 74

LIST OF TABLE

LIST OF SYMBOLS

CHAPTER 1

1.1 Project

1.2 Problem Statement

1.3 Objectives

1.4 Scope of Study

CHAPTER 2

2.1 Corrosion in Pipelines