Evaluation quality of fabrication construction project of lilama 18 jsc

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_—

, ovay Brussels School vuamsegum

_ Economics & Management _ MASTER PROGRAMS | 47' A FINAL REPORT MASTER IN BUSINESS QUALITY AND PERFORMANCE MANAGEMENT EVALUATION QUALITY OF FABRICATION CONSTRUCTION PROJECT OF LILAMA 18 JSC TRƯỜNG DAI HOC MO TP.HCM THU VIEN

INSTRUCTED BY: PROF JACQUES MARTIN WRITTEN BY: NGUYEN DUONG HUY

ID CODE: MBPQM307

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Evaluation quality of Fabrication stage for Construction Project of LILAM: Table of Contents KXVV2//00069)06.1069.(9) ).0 T12 i ACKNOWLEDGEMENNT nành rên ii COMMENTS OF PROFESSOR .0 c.cccescceccsessessesesseseeseceseaseesseessesasseeassesseseeaeanesees iii KV )0/9)0069)/05000151558 1 ,.: iv Ð:/1492.0100/9.49))1900 0/9) 01815818 1 I Introduction about LILAMA 18 JSC . ccĂcStsetererererrrrrrrrrrrrrrree 1 IL Introduction about Construction Project .cseseseeceseseesessssesesesesenensnecarseseneeeereeesesee 5 IIL Introduction about Company’s Quality System oo seesessseeetereesectscseseseserseesassenees 8 CHAPTER 2: MAPPING THE PROJECT .c.ccccscscsseesesseseseseeesnseessaseeessnsesseseenseeeasee 13 L Project FÏOWCHiAFFL x3 vn TH TH TT Hà gi 13

II Fabrication Stage sành HH TT TT g1 re 13

CHAPTER 3: EVALUATION QUALTITY OF EABRICATION STAGE 29 I Identify defects and Non-confOrmitiĐ ôc2 nhng tre 29

II Root cause analysis sesvististirtististnvintintnsiststieieteieienetetetntstststistntnteee _—— 30

III Evaluation defect for cach DFOC€§S - 5 vn ng nghe 31 CHAPTER 4: CONTINUOUS IMPROVEMENT 5c 42 I Analysis affect of defect to project for each process cssesssesesseetetseseassesetenstseseesesee 42

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Chapter 1: Introduction Chapter 1 ; Introduction

This Chapter introducing about Company Profile, Project Description and Company’s Quality System

INTRODUCTION ABOUT LILAMA 18 JSC

1 Brief Introduction of Company

Company name:

Vietnam name: Công ty Cổ phần LILAMA 18

English name: LILAMA 18 JOINT STOCK COMPANY

Transaction name: LILAMA 18 JSC

Established in 1977, LILAMA 18 JOINT STOCK COMPANY is one of the most powerful member Companies of Vietnam Machinery Erection Corporation In 30 years of non-stop development, LILAMA 18 JSC has obtained a stable standing in the field of

machinery erection and equipment manufacturing of Vietnam, reliable to domestic and

foreign counter-partners with good reputation and high quality through series of

completed projects

With such achievement, LILAMA 18 JSC has been awarded third Grade Independence

Order, labor Orders (I, II, II) by the Government and 12 gold medals for high quality by Vietnam Labor Union of Construction

Quality management system ISO 9001: 2008

Member of American Society of Mechanical Engineer (ASME) 2 Company scope of Business

a Survey, design, construction consultant of the industrial line and civil project;

b Survey, design and construction of transportation projects (bridge, road, jetty and airport);

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Chapter 1: Introduction

ce Design of pressure tanks and vessels according to ASME International Standard and various storage tanks;

d Construction of industrial and civil projects, transmission line, transformer station up

to 500KYV, urban and industrial zone infrastructure;

e Trading, import and export of various type of material, mechanical, electrical, thermo- freezing equipment; building material, refractory and insulation material;

f Production of building material;

g Fabrication and erection of lifting equipment and under pressure equipment Supply,

installation and maintenance of elevator;

h Fabrication & erection of steel structure, non-standard equipment, oil rig jackets, fuel oil & chemical cylindrical storage tanks, spherical tanks having big volume;

i Installation of industrial and civil projects in the fields of civil work, power plants, chemical plants, steel plants, foodstuff plants, cement plants

j Undertake to perform EPC projects

k Real estate business

3 Address of subsidiary offices e HEAD OFFICE: Address: 9 - 19 Ho Tung Mau street, Nguyen Thai Binh ward, District 1, Ho Chi Minh City Tel No.: 84-8-38298490, 84-8-38217474 Fax No.: 84-8-38210853

Website: www.lilamal8.com.vn and www.lilama18.com Email: lilamal 8@hem fpt.vn e LILAMA 18-2: Address: No 64, “Kenh Tam Thuoc” Hamlet, Kien Luong Town, Kien Giang Province Tel No.: 84-77-3853276 Fax No.: 84-77-3853830 Email: lilamal 82@lilamal8.com.vn e LILAMA 18-3: Address: No.: 45, 30/4 Street, Ward 9, Vung Tau City Tel No.: 84-64-3838408 Fax No.:84-64-3838336 Email: lilamal83@lilamal8.com.vn

e Steel Structure and Mechanical Equipment Fabrication Factory:

Address: Tan Lap Hamlet, An Dien Commune, Ben Cat District, Binh Duong Province Tel No.: 84-0650-3554062

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Chapter 1: Introduction Fax No.:84-0650-3554061 Email: factory@lilamal18.com.vn 3 4, Founding shareholders Charter Capital: 80,500,000,000 VND (Eighty billion Five hundred million Vietnam Dong) List of founding shareholder:

Share Value Capital No Full name Share Volume (thousand contribution

VND) ratio (%)

State capital representatives:

Le Quoc An

1 ne Sy Quynh 3,570,000 35,700,000 51.00

Tran Quoc Toan

2 | And 1,201 other shareholders 3,356,500 33,565,000 47.95

3_ | Dang Quoc Anh 39,200 392,000 0.56

" 4_ | Pham Van Van 34,300 343,000 0.49

Legal Representative of the Company: Full name: Le Quoc An

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II INTRODUCTION ABOUT CONSTRUCTION PROJECT

1 Project Description

a Introduction

Vietsovpetro (VSP) is undertaking the development of White Bear oil field in the Cuulong Basin, South-Eastern Offshore of Vietnam situated approximately 120 km from the Vungtau coast The White Bear commercial arrangement area will be developed by a wellhead platform to process and export oil, gas and condensate from this field These productions will be transported by pipeline to CTK3 platform in White Tiger field for separated production and after that exported via the FSO Platform mentioned herein after

in this report is the well-head platform GTC1 b Description

As per VSP’s data in GTC-01 zone of White Bear oil field, the mean sea level is 47.3m

shall be used in the design

The GTC1 platform is a satellite drilling and riser platform with 10 number 711mm diameter conductor, 2 number 762mm diameter conductor, a sub-main deck (module

support frame - MSF), and topsides It is a four-legged fixed template type platform

The GTCI jacket is typical 4 legged jackets which is battered 1:10 at Row |, and 1:6.24675 at Row 2 The legs at Row 1 where the jack-up rig enter shall be vertical

There are two boat-landings at Row A and Row B, two caissons at Row A, eight risers at Row 2, and two J-tubes at Row 2

The platform working points are located at EL (+) 7.500m and the four-legged MSF and

topsides is spaced at 14.0m x 20.0m

The MSF consists of transition stub pile, support legs, and sub-main deck levels at

elevation: (+) 15.0 m

The topside consists of 4-level topside which accommodates permanent, a helideck, a vent

boom, and riser facilities The topside levels consist of:

- The main deck levels at elevation : (+) 19.0 m - The platform levels at elevation :(Œ) 22.5 m - The upper deck levels at elevation : (?) 27.0 m

- Top of helideck is at elevation (4) 36.9 m

Final Report, Master in Quality Management ~ Nguyen Duong Huy ~ MBPQM307

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Using 4 main piles (in-leg piles), jacket has not any skirt piles Instead of using cement "7"

grout, pile spacers are placed at framing-plan elevations and some intermediary positions 6

inside jacket leg For more details of “Pile make-up” and “Pile spacers”

The White Bear commercial arrangement area will be developed by a wellhead platform to

process and export oil, gas and condensate from this field

The GTC-01 platform is configured for drilling by Jack-up rig in cantilever mode from onside, by the following technological operations:

Collection and distribution of well production for metering and transportation Metering of oil, water, gas

Distribution gas - liquid mixture discharge of wells with gas content 200m3/T (in normal condition) and mixture with gas content until 50m3/T (in normal condition)

Collection and utilization of industrial waste

Automatic disconnection of well in the emergency situation

Carrying out of underground overhaul of wells with help of Drilling Rig

To kill possibility wells through process pipeline (P= 25.0Mpa) from service ships Design productivity ofthe block-conductor :

e Gas: 1100000 m3/day (in normal condition)

One well maximum output should be:

e Liquid: 500 +1200 m3/day

Quantity of risers: 04 risers (01 9324 and 03 G219)

Quantity of fire water caissons: 02 (9508) Quantity of J-tube: 01 (219)

The platform working points are located at EL (+) 7:500 and the four-legged topside is

spaced at 20.0m and 14.0m

Two boat-landings are to be installing along length side of jacket

Existing Subsea-template for 02 pre-wells (conductors @ 762) are GT-1X & GT-2X

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oO

INTRODUCTION ABOUT COMPANY’S QUALITY SYSTEM 1 Quality Policy

LILAMA 18 JSC is striving to become a leading company to the Vietnamese market by supplying mechanical products manufacture and construction service fields with the

following commitments:

¢ Ensuring that customer specified requirements as well as the appropriate statutory and regulatory requirements are met by LILAMA 18 JSC

e Applying technical progress and new technologies in production and construction field

for:

Y Ensuring quality of mechanical product and construction service

Y Optimizing costs to get competitive price Y Convenient transaction and delivery on time

e Communicating the Quality Policy at all levels of LILAMA 18 JSC to make everybody

understand consistently with the Quality Objectives, and implement together in order to

get expected efficiency

he effectiveness of the Quality Management System following ISO 9001:2008 Standard

requirements in LILAMA 18 JSC 2 Company’s Quality System

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MODEL OF A PROCESS-BASED QUALITY MANAGEMENT SYSTEM

Measurement,

analysis and

improvement

_ NOTE: ————è> Value adding activities < ->» Information flow

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@——¬

Management of internal 4 CONSTRUCTION Purchasing service =

work assignment contract M4 74 TASKS ASSIGNMENT KTKT-WI-7.1 KTKT-WI-7.4 - ‡ Establishing of Project Design & Development Quality Plan KTKT: QLCL-WI-7.1 Human resource management TCHC-WI-8.2.1

Control of fabrication, repair,

replacement and equipment & steel |» structure assembly BVTC-WI-7.5.1-1 1 Y Control of training process TCHC-WI-6.2.2 Control of construction equip- Control of equipment Installation process F—*| ĐVTC-WI-7.5.1-2 mint repair and maintenance QLM-WI-6.3-1 Mobilization of construction equipment control

Control of maintenance, painting &

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ERTIFICATE OF APPROVAL

Certificate

Litama 18 Joint Stock Company oe a

+19 Ho Tung Mau Street, District 1 Ho Chi Mink City, Vietnam

LILAMAI8

JOINT STOCK COMPANY ISO 9091:2008

awarded with the

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Chapter 2: Mapping the Project

L

Chapter 2 1

Mapping the ProJect |

This Chapter indicated about Project Schedule, Detail of

Procedure of Fabrication Stage from signing contract to as-built and handover to Owner

PROJECT FLOWCHART

This flowchart indicated about step by step for a project From beginning when sign contract

from owner, basic design according to contract request, and contact with vendor for purchase order, kick-off meeting After that, a project goes through detail design phase When all detail design complete, all drawing will be sent to vendor and fabrication stage is started After all, a

project leads to commission stage and give as-built drawing to owners

( Study Basic Contact Purchase

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Chapter 2: Mapping the Project 2 Flowchart of Fabrication Stage

15

Fabrication stage included:

¢ Marking: after complete shop drawing, all materials enough and available at site e Cutting — Fitting: after marking

an)

UF

Menvfacture Manual =¬ st hop drawing” ‘| _¬ = Procurement

pecvont > cfeeaanE^ đã sont) Spection BS ` me ad apn) A3 Size Drawing ( ‘es SD Cen —] TC em} at me cà = ( Coatirg fa Repeat B ee End

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1 Project Manager

e Main responsible for all operations -of the project and must supervise all 17 employees assigned to the task

® Make Project Quality Plan

e Planning, reviewing compensation actions and monitoring of the implementation of construction plan

e Arrange and monitor the manpower, machines, construction equipment e Contact with vendors

¢ Create and adjust the construction schedule regarding to production requirements 2 Deputy Project Manager

¢ Checking personnel to perform the work assigned to ensure schedule, quality and the safety of the personnel and company’s property

e Execute directly at the construction site

¢ Follow production schedule and project progress

® To support PM the mobilization of personnel and equipment at the construction site

® Incharge of PM at site when PM absent 3 Construction Manager

¢ Checking personnel to perform the work assigned to ensure schedule, quality and

the safety of the personnel and company’s property e Incharge of PM when authorized

® Incharge of the quality profile of project

4 QA/QC Manager

¢ Monitor and control the application and maintain ISO 9001:2008 system of LILAMA 18 for all activities in project

¢ Check implementation of project quality plan

¢ Determine what parameters, what stage in work’s progress must be checked

Determine the urgency of these parameters and consider the need to check before,

during or after fabrication or not?

¢ Check implementation of quality processes at site

¢ Monitoring and product quality testing, determine the status of inspection and testing of products in the production process, from raw materials to final product ¢ Propose corrective and preventive actions and associated with PM and the QC

Department for the nonconformity product (if the nonconformity product affect

the financial problems, it necessarily reports to the board before making a decision and resolving)

5 Safety Manager

¢ Monitor and inspect the implementation about regulations on the safety of

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Chapter 2: Mapping the Project e Prepare facilities, equipment and construction tools regarding to request of the 7 Document Controller e Incharge of project document 8 Fabrication Supervisor

e Receive work from PM and deploy to fabrication teams

e Checking personnel to perform the work assigned to ensure schedule, quality and the safety of the personnel and company’s property

e Incharge of fabrication supervisor

¢ Create quality profile

9, Welding Supervisor

¢ Mainly responsible for all construction activities of welded team

e Incharge of supervisor of welding team

e Receive work from PM and deploy to welded teams

ø Checking personnel to perform the work assigned to ensure schedule, quality and the safety of the personnel and company’s property

10 CAM Supervisor

e In charge of supervisor of welding team

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Chapter 2: Mapping the Project 4 Detailed Procedure and Flowchart " 19 a Marking: i, Procedure Receipt of materials Receiving inspection (0 ; YêS NO i ill/Certi : Verity NA Check Make report (4) 2 _— ì report >| Quarantine {6) Reparr (7) Receiving inspection 4 report [3] Transfer (marking Mark number on materials (9) F——>} issued material to workshop (10) ——> Cutting (12) —Đ| +stamp) number of ` material (12} - on Material traceability

fit up and %eld (14) |] reports (13)

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Marking included:

e Control dimension of material before cutting

Explanation:

(0): Receive material from Suppliers (1): Checking:

e Quantity: enough or not?

e Have Certificate of Origin and Certificate of Quality or not?

e Checking overall outside by visual: have rust, convex, concave, deform, damage or not?

e Checking dimension (thickness)

(2):

¢ Verify Certificate of Origin (shipping)

e Verify Certificate of Quality (Physical, Chemical) (3):

¢ Report about material’s conformity

¢ Have report about non-conformity record and repair if any

(4): Making report about material’s conformity condition according to (1) and (2) (5): Report about discrepancy between criteria by design and actual (gaps/errors) (6): Review and give solution

(7): Repair or replace (8): Accept/ don’t accept

(9): Mark number on materials ii order to avoid mistaken with others or tracing materials when having problems

(10): Issued material to workshop when receive Material Request from Fabrication team

(11): Marking detail on material follow to Cutting Plan and Cutting

(12): Transfer material code (Marking and stamp) to detail will be cut (13): Making material traceability report (if any)

(14): Fittings or assembly and tack weld

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Chapter 2: Mapping the Project 1i Checking procedure MARKING CHECK PROCEDURE PERSON FLOWCHART IN CHARGE (acœw MATERIAL lS——¬ ECEIVE ERIAL MATERIAL TEAM MATER! EAM XS % CHECKING \, ANTE EAN S an MATERIAL TEAM,

STORE IN MARKING TEAM +

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Cutting included:

e Control material, dimension of detail after cutting 23

(1):

° Materials ensure follow receiving requirements

¢ Detail and making make sure according to Cutting Plan

(2):

e Checking dimension of details before cutting

e Checking traceability numbers on material

(3): Cutting operation must follow instruction (Plasma, Gas ) (4):

e Checking dimension detail after cutting

e Checking traceability numbers are transferred or not?

(5):

e Prepare surface according to design drawing

e Cleaning before tack weld (clear dust, oil, sand )

(6):

e Checking weld gap

e Checking groove angle

e Cleaning

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Chapter 2: Mapping the Project c Welding 1.Procedure 24 Prepare Material (1) _ Check Welder Qualification Qualification (3) Tư nà WPS/POR ((4) (3) `—————— (Dronars welding odee Prepare welding edge y (5) a

[ Pre-heating (6) Ƒ— Tack welding (7)

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Welding included:

¢ Control material according to Certificate of Origin and Certificate of Quality

e Control welds quality by Nondestructive Test and Post Weld Heat Treatment

Welding Checking procedure included:

¢ Checking dimension before and after welding works e Assigned person or team responsible for each process Explanation:

():

e Materials meet requirements: marking and stamp

¢ Welding materials should have Certificate of Origin and Certificate of Quality

(2):

e Prepare Welder test procedure and material sample test ¢ Third Party prepare Welder Qualification test

(3): Check welder regarding to Welding Procedure Specification and Procedure Qualification record

@):

e Prepare tack welding procedure

e Test welding procedure

e Make report after test welding procedure on sample e Issue official welding procedure

(5):

e Cleaning welding edge before welding process

e Make sure groove welds/ fillet welds meet requirement

(6): Heating materials before weld (depend on specification of each material, heating method should be difference)

(7): Tack welding after Fitting team checking dimension (8): Checking dimension after weld

(9): Welding complete

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(11): Post Weld Heat Treatment by several methods regarding to each materials: e Wrap heating tape for piping

e Use furnace for equipment or fabrication product

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Coating included:

e Checking cleaning surface process before coating 28 © Control environment condition with supporting equipment

e Control coating procedure, quality of painting layer

Explanation:

(1): Cleaning process included:

* Remove dust on surface by using suitable mechanical equipment

® Deoxidize surface (using cleaning solvents and high pressure water to clean whole surface) © Cleaning using sandblasting or copper slag to meet standard (2): e Checking cleaning level by compare with standard (has similar color with acceptance level) © Follow instruction strictly (3):

¢ Prepare coating material, solvent, coating procedure

® Mixing paint equipment

e Coating components checking equipment

(4): Checking regarding coating procedure

(3):

e Prepare hygrometer

e Prepare cover facilities during coating process in order to protect against weather factors (wind, dust )

(6):

e Checking about humidity

e Weather: strong wind or not?

¢ Painting surface: wet or dry?

¢ Environment and working temperature

(7): Prepare protection and safety equipment for workers (8): Painting regarding to coating procedure

(9): Checking painting quality: layer thickness, painting material, drying time and follow

painting instruction or not?

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Chapter 3: Evaluation quality of Fabrication Stage

Chapter 3

Evaluation quality of Fabrication Stage

This Chapter indicated about weak-point and nonconformity of Fabrication Stage: Marking, Cutting-Fitting, Welding, Coating and identified causes with data analysis

IDENTIFY DEFECTS AND NON-CONFORMITIES

Following table will indicate each defect and cause lead to them As well as it also show where dysfunction defects or weak point defects are

If defects are weak point type, project can go through at that time but it will lead to problem in near future

If defects are dysfunction type, project should delay intermediate and it only start again when defects are solved

Task Defects Causes Dysfunction Weak point

Marking | Plate convex/concave ¢ Material quality x

e Plate lack of dimension e Material quality x e Wrong material’s type e Supplier problems x

e Misplace trace number se Not follow x

instruction

Cutting- |e Cutting plan mistake e Design quality x

Fitting e Cutting equipment ability |s Technical problem x

e Lack of dimension of x

cutting edge e¢ Human skills

e Weld gap defect x

e Human skills

Welding |e Crack Not follow x

e Proposity instruction: welding in x

e Lack of fusion bad condition, x

âô Underfill supervisors x

e Splatter x

e Excessive convex /concave

s Unacceptable weld profile x

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Chapter 3: Evaluation quality of Fabrication Stage

Task Defects Causes R Dysfunction Weak point

Coating |e Running/Sagging e Coating skills x j

Crating ® Not clean surface x | before paint | e Paint material damage ® Incorrect storage x | condition : e Prolonged drying time e Incorrect mixing x : paint method

Through this table, main defects of Fabrication Stage can be summarized for each sub-stage

These defects can be divided to three main reasons: Material, Technology and Human skills e For materials defects, it will be affected to project schedule because if materials do not

meet requirements, it will be re-ordered

In other hand, if material shipped from overseas, it takes times to ship again > project

schedule will be delayed > increase cost > financial problem

If material temporary accepted because of project urgently, it will cause big damage in

fabrication stage > cannot repair > re-ordered > increase cost + time > financial

problem,

e For technical/design defects, it also affected to project schedule and take time to repair > increase cost + time > financial problem > affect reputation of company

e For human skills defects, it affected to project quality and schedule > affect reputation of company

For cach reason, it needs corrective action accordingly, such as:

e For materials defects, company needs revise its vendor list, evaluate again if supplier does not meet requirements or eliminate that vendor and replace by others

e For technical defects, company needs arrange internal skills/design training or support design team has change to training oversea

e For human skills defects, company needs to arrange skills test periodically in order to

improve their skills, as well as dissemination ISO standard training for staffs

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II EVALUATION DEFECT FOR EACH PROCESSES 32 1 MARKING PROCESS a, Main Defect No Defect Total % Frequency 1 | Marking on material 357 64.67 64.67 2 | Verify Mill/Certify 80 14.49 79.17 3 | Inspection material 65 11.78 90.94 4 | Repair 50 9.06 100.00 552 100 Defect in Marking stage 100.00 100.00 500 90.94 30.00 79.17 80.00 400 70.00 60.00 300 ma Number 40.00 200 30.00 # 100 80 65 i 20.00 10.00 Marking on Verify Mill/Certify Inspection material Repair | material Comment:

There are 4 main defects: Marking on material, Verify Mill/Certify, Inspection material and Repair is recorded in marking stage On top of that, “Marking on

material” has 357 over total 552 defects and has frequency at 64,67% Others causes

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b Weak point analysis

tint of Defer for Marking Process

No Defect Total % Frequency

|_| Plate lack of dimension 185 51.82 51.82

2 | Wrong material code 37 15.97 67.79

3 | Misplace trace number 355 15.41 83.19 4 | Plate convex/concave 36 10.08 93.28 5 | Wrong material type 24 6.72 100.00 357 100 Defect in Marking process 600 100,00 100.00 93.28 90.00 500 83.19 80.00 400 67.79 70.00 60.00 300 51.82 50.00 185 40.00 400 30.00 an Nunb ae 0 1000 0.00 : % " 3 g RS ở ờ *e Ra e Comment: a `

e Need to have measures to improve by classification, statistical category of material that has the highest frequency in order to find out which suppliers are Therefore, those suppliers will be warned and had to improve their works, if not, they will be eliminated out of company’s vendor list

e In order hand, plate lack of dimension is common problem that causes project would be delayed in order to change other material to meet requirements, (See

Picture 3-1)

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2 CUTTING-FITTING PROCESS a Main Defect No Defect Total % Frequency 34 |_| Cutting edge 226 56.64 56.64 2 | Tack weld 79 19.80 76.44 3 | Clean surface after fitting 48 12.03 88.47 4 | Prepare surface 46 11.53 100.00 399 100 Defect in Cutting - Fitting process 400 100.00 100.00 350 88.47 90.00 80.00 300 76.44 70.00 Be 226 56.64 60.00 : 200 50.00 Number 150 40.00 % 30.00 100 79 4p 36 20.00 0 0.00 Cutting edge Tack weld Clean surface after Prepare surface fitting Comment:

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2 | Weld gap defect 15 36 27 78 | 34.51 88.50

3 | Cutting plan mistake 7 fi 5 19| 841 96.90, Cutting equipment 4 | ability 2 3 2 7| 3.19 100.00 226|_ 100 Defect in Cutting Edge process 250 s8sơ 100.00 100.00 88.50 90.00 200 80.00 70.00 150 60.00 122 53.98 50.00 oe Number 100 40.00 % 78 30.00 50 20.00 19 7 10.00 0 I5» | —= 0.00

Lack of dimension Weld gap defect Cutting plan Cutting equipment

of cutting edge mistake ability

Comment:

e Take data collecting for 3 random products There have 4 defect types, “Lack of dimension of cutting edge” has the most frequency: 53,98% (122/226 total

defects)

reproduce

e Need improve in: check dimension before cutting and cutting equipment

® Lack of dimension of cutting edge is common problem that lead damage to welding process after

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3 WELDING PROCESS a Main defect No Defect Total % Frequency | Welding 144 48.32 48.32 2 | Test NDT 97 32.55 80.87 3 | PWHT 20 6.71 87.58

4 | Prepare welding edge 15 5.03 92.62 S| Check welder qualification 12 4.03 96.64 6 | Tack welding 10 3.36 100.00 298 100 Defect in Welding stage 100.00100.00 300 ore 96.64 875 90.00 250 80.87 80.00 70.00 200 60.00 150 1M 49.32 50:00 ——— Number 40.00 97 % 100 30.00 20.00 50 20 15 12 10 10.00 0 Sil i Ree = 0.00 Welding Test NDT PWHT Prepare Check Tack welding weldingedge welder qualification Comment:

There are 6 main defects: Welding, NDT, PWHT Prepare welding edge, Check

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Comment:

Chapter 3: Evaluation quality oƒ Fabrication Stage :

Take data collecting for 3 random products There have 9 defect types, “Crack”

has the most frequency: 44,58% (144/323 total defects) Cold Cracking

o Caused by a combination of atomic hydrogen, hardenable material, and

high residual stresses

o Location: surface or subsurface Hot Cracking- Solidification

o Caused by dendritic segregation of low melting point constituents during solidification

Hot Cracking - Liquidation

o Caused by HAZ segregation of material in the liquid state during solidification

o Location: surface or subsurface; parallel with the weld

Lamellar Tearing

o Caused by delamination of the base material during solidification and

cooling of weld metal

o Location: subsurface; may be visible at joint

The reason causes by welding material not fit to base material, heating welding

material procedure not follow strictly, PWHT not implementation or welding

current unstable