DEPARTMENT OF MECHANICAL ENGINEERING

UNIVERSITI TEKNOLOGI PETRONAS

STATEMENT OF VERIFICATION

INDUSTRIAL INTERNSHIP REPORT

STUDENT’S NAME : WAN IBRAHIM BIN WAN MAMAT

MATRIC NUMBER : 11526

This is to certify that the above mentioned report is approved and all information

and project involved are NOT confidential.

Supervisor’s Signature : …………………………………..

Supervisor’s Name : Ir. Hj Khairil Nizam b. Khirudin

Senior Inspection Engineer

Gas Plant Processing B, Petronas Gas Berhad

Date :

ACKNOWLEDGEMENT

EXECUTIVE SUMMARY

TABLE OF CONTENT

1. INTRODUCTION

1.1 Introduction to Industrial Internship Program 1

1.1.1 Objective of Industrial Program 1

1.1.2 Scope of Work 3

1.2 Introduction to Host Company (Petronas Gas Berhad) 4

1.2.1 Company Profile 4

1.2.2 PETRONAS Corporate Value 6

1.3 Organization Background

1.3.1 Inspection Section Jobscopes 6

1.3.2 Department Organization Chart 7

2. WORK EXPOSURES 8

2.1 Damage Mechanisms (Refinery and Process Industry)

2.1.1 Corrosion Under Insulation 8

2.1.2 Galvanic Corrosion 10

2.2 Non Destructive Testings (NDT)

2.2.1 Dye Penetrant Testing 11

2.2.2 Magnetic Particle Testing 15

2.2.3 Ultrasonic Testing 18

2.2.4 Radiography Testing 19

2.3 PETRONAS Risk-Based Inspection (P-RBI) 21

2.4 Inspection Reference Plan 24

3. PROJECT AND ASSIGNMENT

3.1 Project Background 27

3.2 Objectives 29

3.3 Root Cause Failure Analysis (RCFA)

5 Why Analysis on Wet Gas Separator 29

3.4 RCFA Problem Statement 31

3.5 Conclusion 33

4. OTHER INVOLVEMENTS 34

5. LESSON LEARNT

5.1 Challenges faced and solutions to overcome 35

6. RECOMMENDATION 36

7. CONCLUSION 37

REFERENCES 38

APPENDICES

Appendix 1: Piping Integrity Management System 39

Appendix 2: Simplified Block Flow Diagram of gas processing 40

Appendix 3: DOSH Registered Equipments for Gas Plant Processing B 41

Appendix 4: Equipment Certificate of Fitness (CF) 42

Appendix 5: RBI Criticality Ranking 43

Appendix 6: Laboratory Analysis Test result 43

Appendix 7: External Visual Inspection equipment report 44

LIST OF FIGURES

Figure 1 : Inspection Section – GPPB 7

Figure 2 : Application of penetrant on the surface 12

Figure 3 : Removal of excess penetrant 13

Figure 4 : Application of developer 13

Figure 5 : Indications of surface breaking 14

Figure 6 : Indication on the weldment 14

Figure 7 : Student demonstrating DPI 14

Figure 8 : Working principle of MPT 15

Figure 9 : Dry method 16

Figure 10 : Wet method 16

Figure 11 : Crane Hook with service induced crack 17

Figure 12 : Gear with service induced crack 17

Figure 13 : Drive Shaft with heat treatment induced crack 17

Figure 14: Lack of fusion in SMAW weld 17

Figure 15: The sound reflected to the probe is displayed on the flaw detector 18

Figure 16 : Illustration of Radiographic test 19

Figure 17 : Result produced 20

Figure 18 : RBI Risk Matrix 21

Figure 19 : Three distinct level namely qualitative , semi-quantitative and

quantitative 22

Figure 20: Simplified Block diagram of RBI Process 23

Figure 21: Before and after internal modification in 2008 29

Figure 22: 2008- No erosion observed 30

Figure 23: 2010 – severe corrosion observed 30

Figure 24: Chronology of Events (Events and Causal Factors) 32

Figure 25: 5 – WHY Analysis 32

LIST OF TABLES

Table 1 : Scopes of Works 3

Table 2 : Yearly Inspection Service Program 7

Table 3 : Comparison of Gamma rays and X-rays 20

Table 4: Continuum of RBI approaches 22

Table 5: Wet Gas Separator equipment data 28

Table 6 : Lab Analysis as per taken on 2 April 2011 at V6-0401 boot 33

Table 7 : Others involvement 34

ACKNOWLEDGEMENT

Alhamdulillah. I would like to express my greatest gratitude to Allah SWT for His

will upon the completion of this final internship report.

My deepest appreciation to PETRONAS Gas Berhad (Gas Plant Processing

B) for the opportunity given to me in order to acquire knowledge during the eight

months of industrial training. Greatful acknowledgement to my personal guidance

and dedicated supervisor Ir. Hj Khairil Nizam B Khirudin, Senior Inspection

Engineer of GPPB who has helping and influence me a lot on my personnal

development.

During my internship, I have also received many guidance and assistance

from many colleagues in Inspection Section, and my special thanks goes to all of

them.

1- Mr. Khairul b Ismail - Inspection Manager, GPPB

2- Mr. Rozaimee Ahamad Zakaria - Senior Inspection Engineer (GPP5)

3- Mr. Zubir b Mat Dahan - Inspection Engineer (DPCU3)

4- Ms. Fatihanum Abdul Rahman - Technical Clerk

5- Mr. Anis B Jusoh - Inspection Technician (GPP6)

6- Mr. M Kamah Md Noor - Inspection Technician (GPP5)

7- Mr. M Azman b Jusoh - Inspection Technician (GPP5)

8- Mr. M Syuraihan b Aziz - Inspection Technician (DPCU3)

9- Mr. M Nazeri Ahmad Sofian - Inspection Technician (Common)

10- Mr. Raja Anuar Raja Ahmad - Inspection Technician (DPCU3

My appreciation also goes to Mechanical Engineering Department and

Student Industrial Internship Unit (SIIU) of Universiti Teknologi PETRONAS for

arranging and guiding me from the beginning till the end of internship program. I

also would like to express special thanks to my UTP supervisor, Dr. Ridzuan Abdul

Latif for his supervision and advice. Not to be forgotten, my appreciation also goes

to my colleagues and family for their continuos supports upon my completion of

internship. Thank you.

I

EXECUTIVE SUMMARY

Industrial Internship Program coordinated by the Student Industrial

Internship Unit of Universiti Teknologi Petronas (UTP) is aimed to produce well

rounded students which is part of the effort in achieving UTP’s mission. Despite of

as an exposure towards the working life, the rationale of this program is to provide

undergraduates with necessary technical and soft skills.

This Industrial Internship Final Report compiles all activities and tasks that

the author had undergone through during the Industrial Internship Period. The final

report is divided into few sections whereby the first section briefly introduce the host

company background, objectives as well as the scope of work done during the

Industrial Internship Program.

Next, the main section illustrate in details of the projects and tasks involved during

the internship period as following:

I. Damage Mechanisms

II. Non-Destructive Testing

III. Risk-Based Inspection

IV. Inspection Reference Plan

V. Analysis of the Project

Lastly, the final section contains the lesson learned, discussions, conclusions

and recommendations to the Host Company and UTP. All related standards, tables,

figures and references are attached in the appendices section for better overview of

the tasks explained.

II

1. INTRODUCTION

1.1 Introduction to Industrial Internship Program

1.1.1 Objective of Industrial Program

The Industrial Internship Training Programme (IITP) is a core course offered to all

third-year student of Universiti Teknologi Petronas (UTP). The students undergo

practical training from 6th December 2010 until 15th July 2011 prior to the

completion of their study. During these 32 weeks of training programme, UTP

students are exposed to the real working environment where they can relate

theoretical knowledge with application in industry. It is the University hopes that the

students will be able to develop skills in work ethics, communication, leadership,

management and other skills during these 32 weeks. There are five main objectives

of the IITP:

1) To integrate theory with practice

In University, student had studied so many theories and the IITP is the chances for

the students to apply and see the application of all those theories. The experience

gain in integrating the theory and hands-on during this IITP had given the author a

better understanding towards the theories and enables the author to appreciate the

theories learnt at the University.

2) To introduce students to work culture and industrial practices

The period of 32 weeks of training programme is a good start for the student to

prepare themselves before entering the real life working environment. Students have

the opportunity to improved the communication and interpersonal skills among the

staffs and advance themselves in using the software and tools related.

3) To give opportunity to students to work with industrial practitioners

The involvement of students in several projects will give them the opportunities to

work with various industrial practitioners from different engineering background.

This will help the students in identi1 their interest and choosing 8 their career path

later on.

1

4) To expose students to potential employers

During these 32 weeks of internship period, students will be working not only with

the staff from the host company itself but also with the client, staff from other

company. With this experience, student will know lots of people from different

companies which later can be the potential employer when students finished their

study.

5) To acquaint UTP students with industry and its programs

Students who undergo the internship program will have the experience of working in

the industry. This is a good opportunity for students to create good acquaintances

with the host company. Students have chances to apply the knowledge they gain in

University and see the applications of every program that they had learnt.

2

1.1.2 Scope of Work

Generally, the scope of works, tasks or projects undertaken during this period is

according to the training shcedule planned at the very first week of internship period.

Both supervisor and author had agreed on several fields to be covered at the

respective weeks. The training schedule is as follows :

Scopes Month

Dis Jan Feb Mac Apr May June July

Introduction to POD/PGB

P-Risk Based Inspection (P-

RBI)

Damage Mechanisms

Non-Destructive Testing (NDT)

Dye Penetrant Testing (DPT)

Thermography

Welding

Pressure Test

Ultrasonic Thickness Test (UT)

Steam Condensate Line

Corrosion Under Insulation

Stress Corrosion Cracking

Pressure Relief Device (PRD)

Plant Turnaround/Shutdown

Extra Tasks

Root Cause Failure Analysis

(RCFA)

Inspection Confidence

Inspection Reference Plan (IRP)

Piping Integrity Management

System

DOSH Packages

Piping Circuit

Corrosion Monitoring

Internship Project (Wet Gas

Separator)

Final Presentation

Table 1 : Scopes of Works

3

1.2 Introduction to Host Company (GPP Complex B, Petronas Gas Berhad)

1.2.1 Company Profile

PETRONAS Gas Berhad (PGB)

PETRONAS Gas Berhad (PGB) was incorporated on 23rd May 1983 and

being among the top subsidiaries of PETRONAS since establishment. PGB’s main

business porfolio is divided into four major divisions namely – Plant Operations,

Transmission Operations, Centralised Utility Facilities and Technical and Facilities

Division. The principle activities of the company are processing of natural gas

produced from the gas fields and transmission of the processed gas to end-users

throughout peninsular Malaysia and some for export to Singapore. The first two are

directly related , the third division supports the gas value chain by supplying

industrial utilities to the various petrochemical plants operating in Kerteh and

Gebeng and the fourth division is a technical services outfit for PGB, which also

extend its expertise in engineering and project management to other entities within

the PETRONAS Group of Companies.

As the sole supplier of processed gad, PGB plays a prominent role in the gas

business value chain. PGB operates as a throughout service company providing the

services of processing and transmission of gas to the various customers on behalf of

PETRONAS for a fee as set out in the gas Processing Transmission Agreement

(GPTA).

Sales gas (Methane, ethane, propane , butane and condensates ) are delivered

through the peninsular Gas Utilisation pipeline system. PGB supplies sales gas to

power stations which account for more than 70% of the consumption of processed

gas. The balance is for the non0-power sector and export to Singapore. The Plant

Operations Division (POD) handles all activities pertaining to the processing of feed

gas whilst the Transmission Operation Division (TOD) comprising of a chain of

regional offices, is responsible for the transmission and delivery of sales gas to end

customers. Apart from the PGU system in Peninsular Malaysia, PGB also owns and

operates two gas distribution systems in Miri and Bintulu, Sarawak.

4

The third division involves marketing, manufacturing and supplying of

industrial utility products to the Integrated Petrochemical Complexes (IPCs) in

Kerteh and Gebeng through the Centralised Utilities Facilities (CUF) Operations.

With regard to its CUF business, PGB operates as a commercial provider of

industrial utility products services to its own customers. The commercial operations

of CUF has commenced in January 2000.

The fourth division involves in engineering and project management services.

Technical and Facilities Development Division (TFDD) is the engineering and

project management arm of PETRONAS Gas Berhad. TFDD also provides services

to other companies within the Petronas Group such as Petronas Carigali Sdn Bhd for

the Sabah-Sarawak Gas Pipeline.

Due to integrated nature and interdependence of the gas business, it is crusial for

PGB to ensure its operations support the requirement of its customers. The company

will continue to focus on sustaining the reliability and efficiency of its facilities with

optimal utilization of resourced.

Gas Plant Processing (GPP)

Since the implementation of the PGU Project 1984, PGB’s gas processing

operations are an integral component of this project. Feedgas from offshore

Terengganu is landed at the GPPs in Kerteh and extracted into various component

namely salesgas, ethane, propane, butane and condensate. The GPP Complex in

Kerteh comprises GPP 1,2,3,4 with a combined salesgas production capacity of 1000

million standard cubic feet per day (mmscfd).

To ensure reliability and availability of gas supply to end users, PGB has

constructed two additional GPPs in Kg Tok Arun, which is approximately 15 km to

the north of existing GPP Complex in Kerteh.

The completion of GPP 5 and 6 in December 1998 and July 1999 respectively each

with a 500 mmscfd salegas processing capacity has boosted PGB’s total gas

processing capacity to 2000 mmscfd.

5

Function/Design Basis of a GPP

1. To produce on-specification products in accordance with customers

requirements namely methane, propane, butane and condensate.

2. To process a wide range of feedstocks from the offshore fields and offgas

from a crude oil terminal

1.2.2 PETRONAS Vision and Mission, Corporate Value

PETRONAS has its very clear vision and achievable mission statement

which define its organisation, guiding our corporate activities and policies.

Vision : To be a Leading Oil and Gas Multinational of Choice

Mission :

- We are a business entity

- Petroleum is our core business

- Our primary responsibility is to develop and add value to this national

resource

- Our objective is to contribute to the well-being of the people and the nation.

Shared Values :

Loyalty - Loyal to nation and corporation

Integrity - Honest and Upright

Professionalism - Committed, Innovative & Proactive and always striving for

Excellence

Cohesiveness - United in Purpose and Fellowship

1.3 Organization Background

1.3.1 Inspection Section Jobscope

The author has been attached to the Inspection Section of Technical Services

Department. Inspection section is an important section in oil and gas industry in

order to enable the operation is complying with The Factory and Machinery Act

1967 and Occupational Safety and Health Association OSHA and working closely

with the Department of Occupational Safety and Health DOSH to ensure plant and

operation integrity.

6

Inspection focus areas are as below :

Yearly Inspection Service Program (ISIP)

Managing Loss of Containment, LOC

DOSH registered equipment

Non-DOSH registered equipment

Piping : P-PIMS

Tankage

Non Standard Repair

Statutory/Insurance/Audit

Turnaround, TA

Certificate of Fitness Renewal

Certificate of Fitness Extension

P- Risk Based Inspection, RBI

PRD : ECA

Initiatives WP/WI Updates

5S PMT

Ad-Hoc

Day-to-day ad-hoc

Slowdown

Mini-shutdown

Others 5S PMT Number

Condensate Tank Assessment

Contract Renewal

Table 2: Yearly Inspection Service Program

1.3.2 Department Organization Chart

Figure 1: Inspection Section – GPPB

7

2. WORK EXPOSURES

2.1 Damage Mechanisms

2.1.1 Corrosion Under Insulation (CUI)

Desciption of Damage

Corrosion of piping, pressure vessels and structure componnets resulting

from water trapped under insulation or fireproofing

Affected Materials

Carbon steel. Low alloy steels, 300 series SS and duplex stainless steels.

Critical Factors

a) Design of insulation system, insulation type, temperature,

environment (humidity, rainfall and chlorides from marine

environment, industrial environments containing SO2) are critical

factors

b) Poor design and/or installations that allow water to become trapped

will increase CUI

c) Corrosion rates increase with increasing metal temperature up to the

point where the water evaporates quickly.

d) Corrosion become more severe at metal temperature between the

boiling 1000C-120

0C, where water is less likely to vaporize and

insulation stays wet longer.

e) Insulating materials that hold moisture can be more of the problem.

f) Equipment that opertaes below the water dewpoint tends to condense

water on the metal surface thus providing a wet environment and

increasing the risk of corrosion.

g) Damage is aggravated by containants that may be leached out of the

insulation such as chlorides.

h) Plants located in areas with high annual rainfall or warmer, marine

location are more prone to CUI

i) Environment that provide airborne contaminants such as chlorides or

SO2 can accelerate corrosion.

8

Affected units or equipment

a) Carbon and alloy steels are subject to pitting and loss in thickness

b) 300 series SS, 400 series SS and duplex SS are subject to pitting and

localized corrosion.

Causal Factors

a) Location issues

Common area of concern in process units are higher moisture areas

such as those areas down-wind from cooling towers, near stream

vents, deluge systems, acid vapors, or near supplemental cooling with

water spray.

b) Design issues

i. CUI can be found on equipment with damaged insulation,

vapor barriers, weatherproofing or mastic, or prostrusions

through the insulation or at insulation termination points such

as flanges.

ii. Equipment design with insulation support rings welded

directly to the vessel wall, particularly around ladder and

platform clips, and lifting lugs, nozzles and stiffener rings.

iii. Piping or equipment with damage/leaking steam tracing

iv. Localized damage at paint and/or coating systems.

v. Locations where moisture will naturally collected and

improperly terminated fireproofing.

vi. The first few feet of a horizontal pipe run adjacent to the

bottom of a vertical run is a typical CUI location.

Morphology of Damage

a) After insulation is removed from carbon and low alloy steels, CUI damage

often appears as loose, falky scale covering the corroded component. Damage

may be highly localized.

b) In some localized cases, the corrosion can be appear to carbuncle type pitting

c) Tell tale signs of insulation and/paint damage often accompany CUI

9

Prevention/ Mitigation

a) Since the majority of construction materials used in plants are

susceptible to CUI degradation, mitigation is best achieved by using

appropriate paint/coating and maintaining the insulation barriers to

prevent moisture ingress.

b) High quality coatings, properly applied can provide long term

protection

c) Careful selection of insulating materials is important

d) Low chloride insulation should be used on 300 SS to minimize the

potential for pitting and chloride SCC

e) It is not usually possible to modify operating conditions.

Consideration should be given to removing the insulation on

equipment where heat conservation is not as important.

f) Utilize multiple inspection techniques to produce the most cost

effective approach, including:

i. Partial or full stripping of insulation for visual examination

ii. UT for thickness verification

iii. Real-time profile x-ray for small bore piping

iv. Neutron backscatter techniques for identifying wet insulation

v. Deep penetrating eddy-current inspection

vi. IR thermography looking for wet insulation and/or damaged

and missing insulation under the jacket.

2.1.1 Galvanic Corrosion

Description of Damage

A form of corrosion that can occur at the junction of dissimilar

metals when they are joined together in a suitable electrolyte such as

a moist or aqueous environment, or soils containing moisture

Affected Materials

All metals with the exception of noble metals

Critical factors

a) For galvanic corrosion, three conditions must be met:

i. Presence of an electrolyte, a fluid that can conduct a current.

10

Moisture or a separate water phase is usually required for the

solution to have enough conductivity.

ii. Two different materials or alloys known as the anode and the

cathode in contact with an electrolyte.

iii. An electrical connection must exist between the anode and the

cathode.

b) The more noble material (cathode) is protected by sacrificial corrosion

of the more active material (anode). The anode corrodes at a higher

rate than it would if it were not connected to the cathode.

c) The farther the alloys are apart in the galvanic series, the higher the

driving force for corrosion.

d) The relative exposed surface areas between anodic material and the

cathodic material has a significant affect.

i. Corrosion rate at the anode can be high if there is a small

anode to cathode ratio

ii. Corrosion rates of the anode will be less affected if there is a

large anode to cathode ratio

iii. If there is a galvanic couple, the more noble material may need

to be coated. If the active material were coated, a large cathode

to anode area can accelerate corrosion of the anodes at any

breaks in the coating.

iv. The same alloy may act as both and anode and a cathode due

to surface films, scale or local environment.

Affected equipment

a) Heat xchangers are susceptible if the tube material is

different from the tubesheet, particularly if salt water cooling

is utilized.

b) Buried pipeline, electrical transmission support towers and

ship hulls are a typical location for galvanic corrosion.

11

2.2 Non Destructive Testings (NDT)

2.2.1 Dye Penetrant Test DPT

Dye Penetrant Testing is a surface testing method mainly for detecting surface

breaking defects (opened to surface). This method is easy to handle and applicable to

all materials, except for excessively porous materials like ceramic

Working principle of DPT are:

1. It can only detect surface breaking defects

2. Penetrant must be able to enter the defect to form indication

3. Not suitable for porous or very absorbent materials (wood, cloth, ceramic)

4. Migrating by capillary action (cohesive force, adhesive force, surface tension)

into discontinuities opened to surface

5. Reverse capillary action due to equilibrium action

6. Blotter effect by developer

7. Contrast between the liquid dye and the developer

Basic steps:

1. Pre-cleaning (surface preparation)

- Prevent capillary action from taking place

- Ensure crack is not filled by debris and no surface contaminant

- Pre-cleaning can be done by applying mechanical cleaning, detergent

cleaning, steam cleaning, ultrasonic cleaning etc.

2. Penetrant application on the surface

Figure 2 : Application of penetrant on the surface

- Penetrating fluid (penetrant) applied to component and drawn into defect

by capillary action

- Provide a contrast for detection of indication and apply in excess

- Can be done by spraying, immersion and pouring

12

- Allow time for penetration into cracks within 5-15 minutes and not to

long for it to dry up

3. Removal of excess penetrant

- Remove excess penetrant that is not relevant to crack indication during

development.

Figure 3: Removal of excess penetrant

4. Application of developer

- Provide medium for reverse capillary action to take place

- Provide contrast to the indication (typically white color against red color

of penetrant)

- Developing time is depends on the size of discontinuities (wide crack –

immediate result)

Figure 4: Application of developer

5. Inspection

- Penetrant which pulled out from the defect by the developer forms

indication of the defect

13

6. Post-cleaning

- Removing of penetrant and developer after testing

- To avoid potential corrosion to occur

7. Results

- Final interpretation shall be made after 7-30 minutes after the

development process are satisfied.

-

Indications due to reverse capillary action

Figure 5: Indications of surface breaking

Figure 6: Indication on the weldment

Figure 7: Student demonstrating DPI

14

2.2.2 Magnetic Particle Test (MPT)

Working Principle

A ferromagnetic test specimen is magnetized with a strong field

created by a magnet or special equipment. If the specimen has a

discontinuity, the magnetic field flowing through the specimen will be

interrupted and a leakage field will occur. Finely milled iron particles coated

with a dye pigment are applied to the test specimen. These particles are

attracted to leakage fields and will cluster to form an indication directly over

the discontinuity. This indication can be visually detected under proper

lighting conditions.

Figure 8 : Working principle of MPT

Basic procedures involved the following steps:

1. Component pre-cleaning

When inspecting a test part with the magnetic particle method it is

essential for the particles to have an unimpeded path for migration to both

strong and weak leakage fields alike. The surface should be clean and dry

before inspecting. Contaminants such as oil, grease or scale may not only

prevent particles from being attracted to leakage field, they may also

interfere with interpretation of indications.

2. Introduction of magnetic field

The required magnetic field can be introduced into a component in a

number of different ways.

a) Using a permanent magnet or an electromagnet that contacts the

test piece

15

b) Flowing an electrical current through the specimen

c) Flowing an electrical current through a coil of wire around the part

or through a central conductor running near the part

Two general types of magnetic fields (longitudinal and circular)

may be established within the specimen. The type of magnetic field

established is determined by the method used to magnetize the

specimen. A longitudinal magnetic field has magnetic lines of force

that run parallel to the long axis of the part. A circular magnetic field

has magnetic lines of force that run circumferentially around the

perimeter of a part.

3. Application of magnetic media

Magnetic Particle Test can be performed using either dry particles or

particles suspended in a liquid. With the dry method, the particles are

lightly dusted on to the surface. With the wet method, the part is flooded

with a solution carrying the particles. The dry wet is however more

portable. The wet method is generally more sensitive since the liquid

carrier gives the magnetic particles additional mobility.

Figure 9: Dry method Figure 10: Wet method

4. Interpretation of magnetic particle indications

After applying the magnetic field, indications that form must interpreted.

This process requires that the inspector distinguish between relevant and non-

relevant indications. The following series of images depict relevant

indications produced from a variety of components inspected with the

magnetic particle method.

16

Figure 11: Crane Hook with service induced crack

Figure 12: Gear with service Induced Crack

Figure 13: Drive Shaft with heat Treatment Induced Cracks

Figure 14: Lack of fusion in SMAW weld

17

Advantages of Magnetic Particle Inspection:

1. Can detect both surface and near sub-surface defects.

2. Can inspect parts with irregular shapes easily.

3. Precleaning of components is not as critical as it for some other methods

4. Fast method of inspection and indications are visibly directly on the

specimen surface

5. Is a very portable inspection method especially when used with battery

powered equipment

Limitations of Magnetic Particle inspection:

1. Cannot inspect non-ferrous materials such as aluminium, magnesium or

most stainless steels.

2. Inspection of large parts may require use of equipment with special

power requirements.

3. Some parts may require removal of coating or plating to achieve desired

inspection sensitivity.

4. Limited subsurface discontinuity detection capabilities. ( maximum depth

0.6” under ideal conditions)

5. Post cleaning and post demagnetization is often necessary

6. Alignment between magnetic flux and defect is important.

2.2.3 Ultrasonic Testing

Working Principle

Ultrasonic Test apply the principle of high frequency sound waves which are

introduced into a material. The reflected sound gives information on the material

under test and signals displayed on a CRT. The sound is transmitted in the material

to be tested.

Figure 15: The sound reflected back to the probe is displayed on the Flaw Detector

18

The distance the sound travel can be displayed on the flaw detector.

The screen can be calibrated to give accurate readings of the distance. The

presence of a defect in the material shows up on the screen of the flaw

detector with a less distance than the bottom of the material. The closer the

reflector to the surface, the signal will be more to the left of the screen. The

thinner the material the less distance of sound travel.

Advantages of UT

1. Sensitive to cracks at various orientations

2. Portability

3. Safety

4. Able to penetrate thick sections

5. Measures depth and through wall extent

Disadvantages of UT

1. No permanent record (unless automated)

2. Not easily applied to complex geometries and rough surfaces

3. Unsuited to course grained materials

4. Requires highly skilled and experience technicians.

2.2.4 Radiographic Test

The radiographic testing applied the electromagnetic radiation which is

imposed upon a test object. Radiation is transmitted to varying degrees

dependent upon the density of the material through which it is travelling.

Variations in transmission detected by photographic film or fluorescent

screens. Applicable to metal, non-metals and composites

Figure 16: Illustration of Radiographic Test

19

There are two common radiographic source which are Isotopes produces

Gamma rays and X-ray tube.

Gamma Rays X-Rays

Safety Constraint emission Can be switched off/on

Capabilities Very high penetrating

power

Intensity and wavelength can

be adjusted

Quality of

images Lower quality Better quality

Handling Easier to handle

X-ray machine are bulky,

fragile and requires

electricity

Cost Cheap Expensive

Table 3 : Comparison of Gamma Rays and X-Rays

Figure 17: Result produced

20

The advantages of RT are:

1. Permanent record

2. Detection of internal flaws

3. Can be used on most materials

4. Direct image of flaws

5. Real-time imaging

6. Can detect very thin thickness (small bore piping)

The disadvantages of RT are:

1. Health hazard

2. Sensitive to defect orientation

3. Limited ability to detect fine cracks

4. Access to both sides required

5. Limited by material thickness

6. Skilled interpretation required

7. Relatively slow

8. High capital outlay and running costs.

2.3 PETRONAS Risk-Based Inspection (P-RBI)

Introduction to RBI

Risk-based Inspection is a systematic data analysis of equipment condition to

determine the associated risk with its operation. It is a method for prioritising

equipment for inspection based on risk. RBI will determine risk associated

with operation of specific items of equipment and the key issues driving the

risk. Other than that RBI is an important decision making tool for inspection

planning.

Figure 18: RBI Risk Matrix

21

Risk Definition

Risk is simply a multiplication of probability of failure and Consequences of

Failure.

Probability of failure is a measure of events per year and is referring

to types of equipment, deterioration of the equipment and the uncertainty in

the equipment condition. While consequence of failure is a measure of impact

per event and is based on the loss of containment (process safety,

environmental impact, reputation and asset)

Continuum of RBI Approaches

Figure 19: Three distinct level namely qualitative , semi-quantitative and

quantitative

Balance is required to select most suitable approach

Qualitative Quantitative

Ease of implementation

Less costly

Require presence of SME

Difficult to audit results

Sensitive to expert view

Data intensive

Sensitive to data quality

Costly

Able to audit

Executed as part of large exercise

Table 4: Continuum of RBI approaches

22

RBI Process

Simplified block diagram of RBI process showing essential elements of

inspection planning based on risk analysis regardless of approach is a below:

Figure 20: Simplified Block diagram of RBI Process

The RBI process consists of performing a risk assessment of the

equipment, then determining inspection frequencies and scopes. Many types

of RBI methods exist and are currently being applied throughout industry.

Technologies behind RBI

In developing the Risk Based Inspection, there are technologies involve in

order to enhance the reliability of the data analysis.

a) Materials and construction

b) Corrosion and failure mechanisms

c) Process and operations

d) Inspection and maintenace

e) Safety and risk analysis

f) ICT

The need of Risk Based Inspection

a) Reduce risk of high consequence failures

b) Manage risks associated with inspection programs

c) Facilitates reallocation of resources from lower to higher risk equipment

d) Plant optimization ( inspection techniques and maintenance

23

RBI Benefits to plant/end users

The RBI approach gives benefits to the plant operation and the end users. It

provides the capability to define and measure risk, creating a powerful tool for

managing many of the important elements of a process plant. It allows management

to review safety in an integrated, cost effective manner. On the other hand, it

systematically reduces the probability of failures by making better use of the

inspection resources and finally improves the integrity of plant equipement.

Impacts of RBI

a) Improves communication across organization

b) Able to translate engineering concern into management interest

c) Emphasis on importance of data management

d) Improved inspection work quality.

2.4 Inspection Reference Plan (IRP)

IRP Management

Inspection Reference Plan Management is another management practice for

inspection activities and effectiveness. This practice will relate to equipment type

and criticality category from the RBI and provide linkage to identify failure modes. It

will also create a dynamic inspection plan by concerning the methods, location,

extent and frequency. Other than that, by practicing IRP, the condition of monitoring

confidence can be evaluated and also proposed recommendation of reducing or

increasing inspection frequency.

The IRP should be designed with other mitigation plan so that all equipment will

have resultant risks that are acceptable. There are few considerations in developing

IRP which includes the following;

1. Risk ranking and drivers

2. Inspection history

3. Number and results of inspection

4. Type and effectiveness of inspection

5. Equipment in similar service

6. Remaining life 24

Risk ranking and drivers

Risk ranking is used to prioritize equipment in an inspection program. Risk

drivers ( consequence factors and probability factors) will determine the possibilities

for risk management by inspection.

Number and effectiveness of inspection

Inspection will only effective if the inspection technique chosen is sufficient for

detecting the deterioration mechanism and its severity.

The level of risk reduction will depend on :

a) Mode of failure of the deterioration mechanism

b) Rate of deterioration

c) Detection capability of the inspection technique

d) Scope of inspection

e) Frequency of inspection

Inspection Strategy

Effectiveness of past inspection impact on present risk. Future risk can only

be impacted by future inspection. The key parameters of the inspection strategy are:

a) Type of NDT selected

Types of NDT selected will depend on:

1. The deterioration mechanism to be detected and/or monitored

2. Accessibility to expected deterioration

3. Operational constraint such as temperature

Any equipment maybe subjected to a number of deterioration mechanism –

each of which will impose its own requirements for frequency and coverage.

b) Location and extent of inspection

The consequence of failure (CoF) of an equipment may be used as a

determinant in determining the appropriate location and extent, for example a

high consequence may be related to a high degree of coverage.

The location and extent shall relate to the particular part of the equipment

where the deterioration is most likely to take place.

The nature of the inspection technique chosen will also influence the location

or extent of inspection.

25

c) Frequency of inspection

Frequency of inspection should have a relationship to the rate of

deterioration and the remaining life of the equipment. Increasing the

frequency may not contribute to risk reduction

d) Internal of external inspection

Risk reduction by both internal and external inspection should be

assessed. Often external inspection with effective on-stream inspection and

process monitoring can replace the need for intrusive inspection without

unduly increasing the risk. Invasive inspection may in some case, increase the

risk of the item for example:

a) Moisture ingress

b) Lining damage

c) Risks associated with shutting down and start-up

e) Procedures and practices.

Inspection procedures and the actual inspection practices can impact

on the ability of inspection activities to identify, measure and monitor

deterioration mechanisms.

Comprehensive procedures and practices applied by a competent staff can be

highly effective. Poor procedure and practices applied by competent staff

may give moderately acceptable results. Poor procedures and practices

applied by inexperience and poorly trained staff will only serve to greatly

increase any risk.

26

3. PROJECT AND ASSIGNMENT

3.1 Project Background

In several processes for manufacturing chemicals or for processing materials

gas streams are produced that are subject to entrainment of droplets of liquid carried

over from prior processing, for example droplets of water or liquid hydrocarbons.

Entrained droplets of small size are referred to as mist. The streams containing

entrained droplets are term wet gas. Frequently, it is desirable to remove entrained

liquid as it will adversely affect further processing of the gas stream. In these cases it

is necessary to remove the entrained droplets, one method for which is to use a wet

gas separator. Such a process also may be termed de-entraining, entrainment

separation or demisting.

Several designs are known for separation of entrained droplets of liquid from

gas stream. A wet gas separator typically uses a contact system to cause the entrained

droplets to accumulate into a stream of liquid that is separated from the gas stream.

Frequently the liquid droplets are treated as particulate matter and removed using

filters, cyclones and other means, as outlined.

The internal of Wet Gas Separator was revamped to improve its separation

efficiency by installing new VDX3-4M Inlet Diffuser Device and Z-Pack De-

entraining Device. VDX3-4M Inlet Diffuser Device is installed at the inlet of the

vessel. Its function is to diffuse, distribute and deliver a uniform horizontal gas flow

above liquid level towards mist elimination internals.

Z-Pack Deentraining Device is vertically installed at the center in front of existing

wire mesh pad. Its function is to separate coarse droplets and suspended solids from

the feed gas stream. It offers first stage mist elimination and reduces the load on the

wire mesh.

Wire Mesh Mist Eliminator is installed at the center of the vessel after the Z-pack

device. It is made of fine wire mesh partitions which are arranged together vertically.

Its function is to draw liquid from the gas stream and channel it downwards.

27

Equipment Data

ITEM NAME : WET GAS SEPARATOR

ITEM NO : V6-0401

CODE : ASME SEC. VIII DIV. 1 1992ED. 1994ADD

OTHER SPEC. : PTS 31.22.20.31 W/AD. SPC NO. 056/3000/005-02, SPC NO.

056/3000/027-01 & RELEVANT PTS SPEC. W/ADD

DESIGN PRESSURE : (INTERNAL) 8.1700 MPA.G

(EXTERNAL) 0.0000 MPA.G

DESIGN TEMPERATURE : (INTERNAL) 70.00 DEG.C

(EXTERNAL) 0.00 DEG.C

OPERATING PRESSURE : 6.58 MPA.G

OPERATING TEMPERATURE : (NORM./MAX) 26.7/30.0 DEG.C

CORROSION ALLOWANCE :

SHELL : 3.000 MM (5.0 WELD OVERLAY : BTM 150 MM)

HEAD : 3.000 MM (5.0 WELD OVERLAY : BTM 150 MM)

NOZZLE : 3.000 MM

RADIOGRAPHY :

SHELL : FULL

HEAD : FULL

SHELL TO HEAD : FULL

WIND : PTS 34.00.01.30 (V10XF = 40.3 m/s

EARTHQUAKE : UBC (1994) ZONE 1, I = 1.O

MATERIAL :

SHELL : SA 516-70 & 304L PARTIAL OVERLAY

HEAD : SA 516-70 & 304L PARTIAL OVERLAY

NOZZLE : SA 350-LF2, SA350-LF2+WELD OVERLAY

SUPPORT : SA 516-70

MAX. ALLOWANCE WORKING PRESSURE (MAWP) : 8.1912 MPA.G

HYDROSTATIC TEST PRESSURE : 12.2868 MPA.G

Table 5: Wet Gas Separator equipment data

During the 2010 GPP 6 Major TA, accelerated metal loss near to the SS weld

Overlay was observed inside the GPP 6 Wet Gas Separator (V6-0401). The initial

findings indicated this could be due to pitting and Inspection team decided to apply

“Belzona” metal coating to mitigate the issue.

28

As the GPP 5 Wet Gas Separator also will undergo an internal revamp in

January 2012, an investigation team was formed to investigate the root cause of this

accelerated metal loss.

The equipment internals were modified in the June 2008 to address separation

efficiency.

The failure has caused the remnant life of the wet gas separator reduced by 4 years

and an extensive repair work needs to be performed.

Figure 21: Before and after internal modification in 2008

3.2 Objective

The objective of this project is to identify the root cause of the accelerated

metal loss at the internal of Wet Gas Separator by applying the Root Cause

Failure Analysis (RCFA).

3.3 Root Cause Failure Analysis (RCFA) – 5 Why Analysis on Wet Gas

Separator

3.3.1 Inspection report findings

By comparison between the internal condition of the separator within 2

years of revamp from 2008 to 2010, a very significant increase of metal

loss was found. In 2008, pitting corrosion was observed to be less than

1.5 mm. However, the pitting corrosion has accelerated to be 4.0 mm to

5.0 mm after 2 years in 2010. Below are the image of visual inspection at

the internal of the separator.

29

Figure 22: 2008- No erosion observe Figure 23: 2010 – severe corrosion

observed

30

Findings at the internal (2008):

c) Pitting corrosion was noted along the

bottom part of internal shell wall, adjacent

to cladding) with maximum depth

approximately < 1.5 mm

d) internal weldment noted in satisfactory

condition

e) manhole noted in satisfactory condition

3.4 RCFA Problem Statement

V6-0401 Wet Gas Separator has experienced accelerated corrosion rate of 0.45

mm/yr compared to 0.15mm/yr allowed since 2008 after major modification

performed on internals of the vessel. The impact over that period had been RM 480

000 loss profit opportunity and RM39 000 maintenance costs.

31

Findings at the internal (2010):

1) East side dish head, sustain with

severe pitting corrosion on area

adjacent to cladding, measured

with maximum depth of 4.0

mm. Appearance like wash

away of metal

2) East side shell wall. Corrosion

attack up to 1500mm from area

adjacent to cladding.

Figure 24: Chronology of Events (Events and Causal Factors)

Figure 25: 5 – WHY Analysis

32

No. Analysis parameters Result

1. pH 5.5

2. Oil & Grease 30.7 ppm

3. COD 243 ppm

4. Conductivity 53.9 uS/cm

5. TDS 24 ppm

6. NH3 0.614 ppm

7. FRC 0.03 ppm

8. Chloride 2.05 ppm

9. Total Hardness 36 ppm

10. Amine As attached

Table 6 : Lab Analysis as per taken on 2 April 2011 at V6-0401 boot

3.5 Conclusion

From the Root Cause Failure Analysis, the erosion-corrosion was identified to

be the major damage mechanism of metal loss. The failure of the equipment is

mainly contributed by the new inlet device which promotes the above damage

mechanisms by changing the floe direction at the inlet region. It has also caused

splashing of water beyond cladded area, consequently bottom vane too close to liquid

surface and acidic water formation.

33

4. OTHER INVOLVEMENTS

Throughout the eight months of internship, the host company had arranged several

programmes and courses which had given the author the opportunities to experience

an extra learning and knowledge. Followings are the involvements of the author :

Events/Training Date

P-RBI Training at NIOSH Kemaman December 2010

POD-GPPB Away Day at Peladang Agro Setiu

Resort January 2011

SAPTE Process Piping Workshop at GPPA January 2011

GPP4 & KCSB TA SOE Development Workshop

at Kelab Golf Rantau Petronas January-February 2011

Centralized Utility Facilities (CUF) ASU2 Mini

Turn Around

20th

February – 4th

March

2011

GPP B Boiler Refresher Training March 2011

GPPB Football Tournament March 2011

HSE Workgroup Champion PGB May 2011

PETRONAS Family Festival, KGRP Jun 2011

Table 7 : Others involvement

34

5. LESSONS LEARNT

Throughout the industrial training, the author had been given tasks and

assignment which are new and not familiar. In industrial application, good

theoritical and technical knowledges are very important. Thus the author has always

building positive attitudes in learning new things. The effort of learning is required

while getting information by reading and researching in completing the tasks beside

the discussion with supervisor and technical staffs. Other than that, the decision

making skills are also being practiced. During discussion and meeting, decision must

be done in the limitation of time and circumstances. Experience and good

understanding about particular subject are helpful in making decision. However,

some of the decision made are with the guidance from many parties.

In addition, being in working environment require one to deal with many

people of various background and level. Here, and excellence discipline and self

control must be developed such as to obey the company’s regulation, dress code and

others. Professionalism is one of the aspects that must be enhanced. Apart from that,

the chance to get involve with industry has encouraged the author to always adopt

good communication and management skills

5.1 Challenges faced and Solutions to overcome

a) First time working experience

The author had never worked in industry, and this industrial training is the

first exposure to the real working environment. The author had taken some

times to adapt with this new environment and had gained new things and

experience from day to day.

b) Learning hands-on engineering aspect

In inspection department jobscopes, one need to have good understanding and

knowledege about the engineering aspects. One must have the ability to

execute the technical jobs. Thus, the author had gain such a great experience

handling engineering problems and calculation.

35

6. RECOMMENDATION

The host company ( PETRONAS Gas Berhad) has provided the author

a wide range of opportunity during internship training in engineering aspects.

The author had been given many involvements and exposures which mostly

related to Inspection field. Credits also should be given to Universiti

Teknologi PETRONAS for enabling such a great medium for students in

attaining real working environment. This industrial training is sufficient for

students to lean and fit themselves in the industry.

6.1 Recommendation to the Host Company

The author would like to suggest the host company to provide

trainee with ample hands-on technical jobs and allow the students

to handle the tasks. It is also suggest that the trainee could be

entertained as staff rather than a students to create self-belonging

to the company and the task given. Besides that, proper assistance

for trainee by preparing the practical handbook would be helpful

to the trainee.

6.2 Recommendation to the University

The author feels that the university should improve the monitoring

system in order to monitor the training program that the student is

undergoing. The supervision which usually done during the first

and second visit is not sufficient. Thus, SIIU should also updated

on the student welfare at the respective company. This will make

the training programme more effective. Apart from that, the

university may revise the internship policies so that students can

get involve with confined space equipment especially for those

working at the processing and refining plant. By allowing the

students to do so, it is believe students could grab more

experience throughout the challenging work exposures.

36

7. CONCLUSION

The eight months period of Industrial Internship Training Programme (IITP)

had given the author the opportunities to learn new things and gained many

experiences through the involvement of various projects and tasks. The IITP also had

allowed the author to developed working skills and work ethics that needed by

current employers. IITP is the best platform to expose the student with the real-life

working experience besides giving them the rough picture of what to be expected

when they have graduate from the University and start a working life.

The eight months duration has not only benefit the author, but also the UTP

and the Host Company. The UTP has managed to build a good rapport with the Host

Company through this programme and the Host Company meanwhile has the

opportunity to evaluate and train their future employees. The author believes that all

the objectives of the IITP that been set by SITU were achieved during the eight

months of the industrial training with close supervision by both sides, the Host

Company (PETRONAS Gas Berhad) and also the University (UTP).

Some recommendations were made to both the Host Company and UTP in

order to improve the training programme in future. This to ensure that future trainee

will not encounter the same problems that the author had. The improvement made

will enhance relationship between both of the parties involved. The author hopes the

IITP will be keep offer in the future due to its voluminous benefit to all.

37

REFERENCES

1. API Publication 580 – Recommended Practice for Risk Based Inspection

2. George Antaki, “ Risk based Inspection in Refineries, Petrochemical Plants

and Oil/Gas Plants”.

3. API 571 – Damage Mechanisms Affecting Fixed Equipment in the Refining

Industry. Recommended Practice 571 First Edition, December 2003

4. Petronas Technical Standard (PTS)

5. API Recommended Practice 579, Fitness for Service, First Edition.

6. Principles of Magnetic Particle testing, American Society for Nondestructive

Testing

7. Charles Hellier (2003). Chapter 7 – Ultrasonic Testing. Handbook of

Nondestructive Evaluation

8. Petronas Gas Berhad, Paka, Terengganu. www.petronasgas.com

9. UTP Internship Guidelines for Student Industrial Internship Programme

38

APPENDICES

Appendix 1: Piping Integrity Management System

39

DEVELOPMENT OF CORROSION GROUP

(MARK-UP ON PFD)

(

START

CLASSIFICATION OF PIPING CIRCUIT

(MARK-UP ON P&ID)

SELECTION OF PIPING REPRESENTATIVE

INSPECTION

EXAMINATIO

N

FFS

RERATE/MOC

INPUT IN RBI

RUN ANALYSIS/CRITICALITY

REVIEW INSPECTION EFFECTIVENESS

DEVELOPMENT OF IRP/MITIGATION

PLAN

Confirm to Requirement

Confirm to Requirement

NCR

NCR

REA

SSES

SMEN

T P

RO

CES

S

Responsible Party

Corrosion Engineer

Piping Inspector

Inspection/Maintenance/

Operation/Engineering/PPL

Piping Inspector/NDE

Examiner

Inspection Engineer/ TP

Inspection

Inspection

Engineer/Operation

Engineer/Maint.Eng/PPL

Piping Inspector

RBI/GTS Engineer

Inspection Eng/ TP Inspection

Inspection Eng/TP Inspection

Interface

Operation/Technologist

Inspection Engineer

Department Manager

Inspection Engineer

TP Inspection

(Principle/Custodian)

Plant Manager

RBI/GTS Engineer

None

RBI/GTS Engineer

RBI/GTS Engineer

Appendix 2: Simplified Block Flow Diagram of gas processing

40

Appendix 3: DOSH Registered Equipments for Gas Plant Processing B

NO DOSH NO EQUIPMENT DESCRIPTION

1 PMT107915 C6-0101 HYDROCARBON STRIPPER

2 PMT107916 E6-0101 HYDROCARBON STRIPPER FEED PREHEATER

3 PMT107917 S6-0101A FEED GAS FILTER

4 PMT107918 S6-0101B FEED GAS FILTER

5 PMT107919 S6-0102A FEED LIQUID FILTER

6 PMT107920 S6-0102B FEED LIQUID FILTER

7 PMT107921 S6-0103 FILTER SEPARATOR

8 PMT107922 V6-0101 INLET SEPARATOR

9 PMT107924 V6-0103 CONDENSATE/WATER SEPARATOR

10 PMT107925 C6-0201A ABSORBER

11 PMT107926 C6-0201B ABSORBER

12 PMT107927 E6-0201 FEED/PURE GAS EXCHANGER

13 PMT107928 E6-0202 SOLUTION HEATER

14 PMT107929 E6-0203A CO2 OFF GAS COOLER

15 PMT107930 E6-0204A SOLUTION COOLER

16 PMT107931 E6-0205 FLASH GAS COOLER

17 PMT107932 S6-0201A MECHANICAL FILTERS

18 PMT107933 S6-0201B MECHANICAL FILTERS

19 PMT107934 S6-0202A CARBON FILTERS

20 PMT107935 S6-0202B CARBON FILTERS

21 PMT107936 S6-0203A GUARD FILTERS

22 PMT107937 S6-0203B GUARD FILTERS

23 PMT107939 V6-0202 LOW PRESSURE FLASH DRUM

24 PMT107940 V6-0203 ABSORBER OVERHEAD K.O. DRUM

25 PMT107941 V6-0204 CO2 OFF GAS K.O. DRUM

26 PMT107942 V6-0205 SOLUTION HEATER COND. K.O. DRUM

27 PMT107943 V6-0206 SOLUTION SUMP TANK

28 PMT107944 V6-0207 FLASH GAS SEPARATOR

29 PMT107945 E6-0301A REGENERATION OFF GAS COOLER

30 PMT107946 S6-0301A DUST FILTERS

31 PMT107947 S6-0301B DUST FILTERS

32 PMT107951 V6-0301 D DEHYDRATOR

33 PMT107953 V6-0302A MERCURY REMOVAL VESSELS

34 PMT107954 V6-0302B MERCURY REMOVAL VESSELS

35 PMT107955 V6-0303 REGENERATION OFF GAS K.O. DRUM

36 PMT107956 C6-0401 DEMETHANIZER

37 PMT107957 E6-0401 WARM GAS EXCHANGER

38 PMT107958 E6-0402 HOT GAS CHILLER

39 PMT107959 E6-0403 DEETHANIZER STEAM REBOILER

40 PMT107961 E6-0406 REBOILER

41

Appendix 4: Equipment Certificate of Fitness (CF)

41

42

Appendix 5: RBI Criticality Ranking

Appendix 6: Laboratory Analysis Test result

43

Appendix 7: External Visual Inspection equipment report

44