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Role of Quality Control

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    ROLE OF QUALITY CONTROL IN SHIP BUILDING

    A Mini Project report submitted in partial fulfillment of

    Requirements for the award of the degree of

    BACHELOR OF TECHNOLOGYIN

    MECHANICAL ENGINEERING

    BY

    K.V.MANI KUMAR[09815A0302]

    S.HARISH [08811A0348] Y.DHANARAJU[08811A0360]

    O.S.SANTOSH KUMAR[08811A0342] M. YAMUNA RAO[08811A0337]

    AVANTHI INSTITUTE OF ENGINEERING AND TECHNOLOGY

    (An NBA Accredited Institution)

    Tamaram, Makavarapalem,

    Narsipatnam,

    VISAKHAPATNAMAM-531113

    Under the Esteemed Guidance of

    Mr. S.K.DURGA PRASAD

    B.com, D.Met., B.E(Indl. Engg), MBA(Mktg), MBA(HRM)

    ENGINEER, QUALITY CONTROL

    HINDUSTAN SHIPYARD LIMITED

    VISHAKHAPATNAM

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    ACKNOWLEDGEMENT

    We express our deep sense of gratitude to Dr. C.P.V.N.J. Mohan Rao,

    principal andMr. N.Rajendra, HOD of Mechanical of AVANTHI College of

    Engineering,for encouraging us to carry out mini project work at HSL and the

    completion of project.We are very much thankful to C.BABU RAO, Sr. P.O, TRAINING DEPARTMENT,

    HINDUSTAN SHIPYARD LIMITEDfor providing this opportunity and their supportto do project work at Q.C department in HSL.

    We express our deep sense of gratitude to Sri. M.V.V.S. GUPTA Chief Manager

    of QUALITY CONTROL Department, K.AKKULAPPA, Manager of QUALITYCONTROL and all Technical and Non- Technical staff of HSL, who encouraged us

    in the completion of project.We wish and express our sincere gratitude to our guide MR. S.K. DURGA

    PRASAD, Engineerand also MR.V. ABBAI, EngineerandMR.V.L. ACHARI, Asst.Supervisorfor their guidance and suggestions throughout the project, withoutwhich we would not have been able to complete this project successfully.

    We extend our thanks to all our friends for their moral support and

    encouragement; last but not least we thank our parents and relatives who

    inspired us to do the best in our project.

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    CONTENTS

    1.INTRODUCTION TO SHIPYARD2.ABOUT QUALITY3.INSPECTION DEPARTMENT4. YARD PROCESS

    4.1HULL SHOP4.1.1Introduction4.1.2 Work instructions of hull shop

    4.2PRE-FABRICATION4.2.1 Introduction4.2.2 Work instructions of pre-fabrication

    4.3ERECTION4.3.1Introduction4.3.2 Work instructions of erection4.3.3Pressure testing/flood testing/leak testing

    5.NON-DESTRUCTIVE TESTING(NDT) METHODS5.1Radiographic testing5.2Ultrasonic testing5.3Magnetic particle testing5.4Liquid penetrate testing

    6. CONCLUSION

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    INTRODUCTION

    Ship is a huge structure and colossal in size consists of high technical equipment

    and powered by diesel engines and with other gear to cater the needs of transport of

    men and material to continental to continental, port to port by sea routes. Shipconstruction is a complex activity, for this purpose manufacture the Hindustan

    shipyard is having a well developed infrastructural arrangements with established

    organization of employees of various categories and construction procedures and well

    planning and also important industrial local environment and good support of the

    government.

    BRIEF OF HINDUSTHAN SHIPYARD LIMITEDThe HINDUSTAN SHIPYARD is a pioneering industry in public sector

    organization owned by the government of India and recently this organization is taken

    by Ministry of Defence (MOD) from Ministry of Surface and Transport (MOST). HSL is

    one of the five major shipyards in our country, owned by government of India. They are

    the

    1. Hindustan Shipyard Limited (HSL)2.

    Cochin Shipyard Limited (CSL)3. Garden Reach Ship Building Engineering (GRSE)

    4. Mazagon Dock Limited (MDL)5. Goa Shipyard Limited (GSL

    Among them Hindustan Shipyard was first established ship building yard in

    our country. This was one of the biggest mile stones in the history of public sector

    development in India

    The HINDUSTAN SHIPYARD LIMITED in Vishakhapatnam is one of the fivemajor shipyards in our country. It was established by NAROTTAM MORARJEE andWALCHAND AND HIRACHAND. The foundation stone was laid on 21st June 1941 bySri BABU RAJENDRA PRASAD the first President of India in at Visakhapatnam of

    Andhra Pradesh at latitude 1748 north and 83 17 east. The construction of theshipyard was completed in 1945. The first ship commenced in 1946.

    So far Hindustan Shipyard has built and delivered 164 vessels aggregating 1.3

    million DWT of the nation. Shipyard has built in the course of construction has big

    ships, Training ships, Drill ships, Offshore patrol vessels & support cum-stand by

    vessels. Floating cranes etc., of different designs.

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    At present shipyard is capable to build bulk carrier up to 80,000 DWT,

    presently 53,000 DWT Bulk carriers are under construction stage.The Hindustan

    shipyard limited with expertise skilled man power & sound technology of hull

    engineering & outfit engineering. Electrical backup facility & also offers excellent ship

    repairs and dry dock.

    The dock also has got the necessary infrastructure facilities under take

    intricate repairs to different types of vessels & can accommodate different types of

    vessels up to 57,000 DWT to 70,000 DWT subject to certain limitation.

    Adjacent to the dry dock, a wet-basin constructed in 1975 to undertake

    afloat repairs of various vessels. Both ship building and ship repairs wings are managed

    by experienced as well as qualified trained staff of 480 officers 984 staff and 1407

    workmen.

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    ABOUT QUALITY

    Quality Control(QC) is a system of routine technical activities, to measure and

    control the quality of the inventory as it is being developed. The QC system is designed

    to:

    (i) Provide routine and consistent checks to ensure data integrity, correctness,and completeness;

    (ii) Identify and address errors and omissions;(iii) Document and archive inventory material and record all QC activities.

    QC activities include general methods such as accuracy checks on data

    acquisition and calculations and the use of approved standardised procedures foremission calculations, measurements, estimating uncertainties, archiving information

    and reporting. Higher tier QC

    activities include technical reviews of source categories, activity and emission factor

    data, and methods.

    Quality Assurance (QA) activities include a planned system of review

    procedures conducted by personnel not directly involved in the inventory

    compilation/development process. Reviews, preferably by independent third parties,

    should be performed upon a finalised inventory following the implementation of QCprocedures. Reviews verify that data quality objectives were met, ensure that the

    inventory represents the best possible estimates of emissions and sinks given the

    current state of scientific knowledge and data available, and support the effectiveness

    of the QC programme.

    Quality is a Requirement of product which confirms the specification &

    customer satisfaction and purpose for intended use.

    QUALITY POLICY:

    HSL management has adopted a quality policy as per the ISO requirements.

    To produce consistently quality products to national and International standards in

    time for customer satisfaction at optimum cost by improving effectiveness of quality

    management system

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    Quality policy : ISO 9001-2000

    To produce consistently quality product

    To maintain national and international standards in time

    TO produce customer satisfaction at optimum cost

    By improving efficiencies of quality management system "

    OBJECTIVES OF QUALITY:

    a) To meet quality requirements societies.b)To ensure safety and reliability of ships during construction as M.M.D rules.c) To ensure competent work force to carry out assigned activities.d)To ensure effective usage of measuring and testing instruments during

    construction.

    e) To minimize defects and re-works during production process.f) To ensure low level defects-free bought out items from approved suppliers.g) To meet production schedules within reasonable variation.h)To ensure liquidation of non-moving standard stock items and reduce inventory

    costs.i) To ensure prompt and effective response/action on receipt of customer

    complaints.

    j) To ensure good housekeeping by regular cleaning of working areas and disposalof scrap.

    k)The surface defects after blasting and priming of plates/ sections attreatmentplants and remarks shall be marked.

    l) Q.C shall inspect the plate and sections after rectification of pitting/ indentationetc.

    m)During process, dimensional checks and edge preparation after marking and gascutting, rolling, and forming.

    Inspection remarks shall be marked on the job and indicated in the

    inspection record sheet. The same shall be checked after completion of the remarks

    and documented.

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    QUALITY ASSURANCE DEPARTMENT:

    QA involves all activities from design, development, production, installation,

    servicing and documentation. It includes the regulation of the quality of raw materials,

    assemblies, products, and components, services related to production and

    management, and inspection processes.

    Inspection is a process of sorting well from a lot. Whereas the quality control is

    an aimed prevention of defects at various sources effective feedback system procedure

    and corrective action. In quality control program, inspection data are used to take

    corrective action to check the defects. For this purpose, detail study is conducted to find

    out that from where the defect is originated and how to prevent, it may be at

    manufacturing design, purchase of raw material, dispatch or storage stage.

    So, quality assurance means to provide the necessary confidence to the

    customer as well as the management that all concerned are carried out their jobs

    effectively and that the ship quality as per customer(owners)satisfaction at optimum

    cost. Quality work can be produced only when all the departments fully participate and

    co-operate.

    RESPONSIBILITY OF QUALITY ASSURANCE DEPARTMENT:

    a. Plan, develop and establish quality policy.b. To assure that products of prescribed specification reaches to the customerc. Regularly evaluate the effectiveness of the Quality Management Systemd. Conduct studies investigation related to quality problems.e. Liaise with different departments, in and out the organization.f. Organize training programs on quality

    WORKING PROCEDURE FOR QUALITY ASSSURANCE:

    1. Quality system and procedure for all departments are prepared and issued to thefollowing departments.

    2. Design drawing office, purchase department, production planning department,material inspection department, material stores and production department like

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    hull shop, pre-fabrication, Erection department and outfit department the

    engineering department, carpentry, Black smith and rigging department.

    3. All work procedures and standards required to individual department theyshould follow the established system procedures.

    4. During the process of the work of the individual department they should followthe established system procedures.

    5. Here quality assurance department plays vital role to over see whether thedepartment are following quality system procedure time to time.

    6. Periodically quality assurance conduct s audit for each and every departmentsand ensures the established system is followed by them.

    7. During audit if it is found that any deviations from system procedures the samewill be corrected in order to established the quality function as per the ISO9000-

    2008 to the concerned departments.8. By function itself quality assurance establish that the organization is functioning

    in line with ISO 9001 system.

    9. As per the quality system procedures the following documents are issued to allthe departments by quality assurance.

    a. Quality manualb. Quality procedurec. Quality standardsd. Quality plane. Quality formats

    Before implementing QA/QC activities, it is necessary to determine which

    techniques should be used, and where and when they will be applied. There are

    technical and practical considerations in making these decisions. The technical

    considerations related to the various QA/QC techniques are discussed in general in this

    chapter, and specific applications to source categories are described in the source

    category-specificgood practice guidance. The practical considerations involve assessing

    national circumstances such as available resources and expertise and the particular

    characteristics of the inventory. The level of QA/QC activities should be compatible

    with the methods or tiers used to estimate emissions for particular source categories.

    In addition, resources should be focused on priority areas, such as the key source

    categories , Methodological Choice and Recalculation, Determining National Key Source

    Categories and source categories where changes have occurred in methods or data

    acquisition since the last inventory compilation.

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    INSPECTION DEPARTMENT

    The purchased and procured material which come to shipyard will be

    subjected for stringent inspections by material inspection department.

    All materials viz. steel plates, paint, electrical equipment, plumbingequipment, machinery equipment, like main engine generators, pumps, motor, all ship

    outfit accommodation equipment, furniture are inspected and inspection reports (IR)

    are generated and issued to all concern department, design offices, purchase

    department,(P.P.C.D), Quality control(Q.C) and all yard working departments.

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    HULLSHOP

    The process of Hull shop is marking and cutting of elements into various sizes

    and forming them into required shapes.

    It consists of 4bays of which 3bays are having cutting machines and last bayconsists of marking and bending section. At first the steel plates are lifted from steel

    storage yard to the captivator by means of overhead cranes, after this the plates are

    carried to the hydro leveler by means of captivator then the plates are processed in

    plate treatment line i.e. blasting and painting.

    The overhead cranes are used to pickup and place the steel elements at different

    places for different process(CNC cutting and plasma machining and forming press

    machines).

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    WORKING INSTRUCTIONS OF HULL SHOP

    SCOPE:

    To establish work instructions which shall be a guide to all personal in this

    department for performing Quality related activities.

    RESPONSIBILITIES:

    The quality related activities and personnel responsible or given in the table

    hereunder

    Quality related activity Responsibility

    Issue and control of drawings Nominated person for this purpose

    Co-ordination of production activities for

    indenting material ,schedules, and other

    relevant inputs

    Officer-in-charge inE3/E2/E1 cadre in his

    are of operation.

    Documenting results and generation of

    inspection records of production

    Respective supervisors/assistant

    supervisors concerned.

    Work distribution --do--

    Execution of work Respective work force

    Reporting of non-conformance or

    deviation from drawing

    Respective supervisors./assistant

    supervisors and above.

    SYSTEM:

    1. Manufacturing documents in the latest version as hereunder shall be referred inthe production process.

    2. Drawings3. Material input from other department and stores.4. HSL quality standards.5. Quality plan

    INSTRUCTION:

    1. plate blasting and priming:2. Pick up the required plate issued by steel stores from the pile. Note down the

    plate size, thickness, IR no. and grade of steel before placing it on the conveyorby the captivator.

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    3. Check the thickness of the plate at entry point of hydro leveler4. If the plate requires mangling, hydro leveler system is to be energized and

    plate straightens.

    5. Ensure that the blasting equipment is in satisfactory working condition that isall rotors, blowers, brushes are functioned.

    6. Ensure that compressed air used for blasting is free from moisture and oil andpressure not less than 5kg/cm2.

    7. Control the speed such that blasting is maintained long enough to ensureremoval of all scale, rust and foreign material should give a surface finish is

    equal to SA 2 - very through blast cleaning. Mill scale rust and foreign

    matter shall be removed to the extent that only traces remaining are slightly

    stains in the form of spots or stripes. Finally the surface is cleaned with the

    vacuum cleaner or with dry compressed air or with aclean brush, built in theblasting unit itself.

    8. Do not leave the plate partially blasted.9. Do not wet or contaminated shots for blasting. They cause more harm.10. If after first blasting, the surface finish as required is not achieved, replace

    the plate and investigate /rectify the cause.

    11. Shake and roll the drum containing base few times before opening. Mixhardener to the base(NOT BASE TO HARDNER) and add thinner as

    recommended by the manufacturer.

    12. Allow 15min saturation time after maximizing13. Ensure compressed air pressure is not less than 5 kg/cm2.14. Ensure uniform dry film thickness of the premier over the full plate, free

    from holidays.

    15. If holidays are found, apply, premier with a conventional spray or roller/brush.

    16.

    If DFT is found less than 20microns, stop priming investigate and rectifythe defect. the load DFT can be compensated by conventional spray

    applications of thin coat of the same premier.

    17. Pot life of primer is 6 hours. Please ensure that after mixing, primer isconsumed within this period clean and flush the system with suitable solvent

    as recommended by paint manufacturers at the end of each shift.

    18. Fill up inspection record sheet no QA-A-01

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    CNC MACHINES:

    1. Check the control drawing NC format by MLDO and check whether allocatedplate dimensions are as per the drawing given.

    2. Pick up the correct plate already blasted and primed, and place on the NC skid.Align the plates on the skids depending on the requirement manually and orwith the help of the crane.

    3. Adjust the torches depending on job requirements i.e. identical orsymmetrical.

    4. Insert the NC tape in tape reader of computer.5. Align the torches to the reference point on the plate and start the machine.6. The machine will do punch marking first, after completion of punching the

    punch off-set will be off. Observe this point.

    7. End of punching is signaled by end of program.8. Now adjust the gas flow/pressure and ignite the torches.9. Start the machine and start the cutting.10. Observe the cutting as to whether it is following11. The profile described in the control drawing. After cutting are over, check

    the dimensions with dimensions given in the control drawing wherever

    applicable.

    12.

    After cutting the burrs slag etc. shall be removed.13. Panel no. /element no./IR no./Drawing no./Ship no./Tape no. shall be

    painted on the elements. Grade of steel (for other than GR. A) Also shall be

    painted on the elements.

    14. Ensure that machine is calibrated every month to avoid errors. Date ofcalibration and due date shall be marked on the machine.

    15. Inform maintenance department/MLDO for any malfunctioning of themachine.

    16. Fill up inspection record sheet QA-A-02.PMC SHEDULES:

    MARKING:

    1. Check the size of the allocated plate/section is asper drawing.2. Mark the lines as per dimensions given in PMC with necessary punch marks.3. Mark the edge preparation required.4. Punch the element no. drawing, ship no., etc, on the elements.

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    GAS CUTTING:

    1. Align the portable gas cutting machine correctly on its track.2. Adjust the gas pressure/flow and start cutting on the marked lines and

    prepare edge as per the drawing given.

    3. If cutting is done on variosec machine ensure proper alignment of plates onthe skids and also ensure the squareness of the machine for parallel cutting.

    4. After cutting burrs and slag are to be removed.5. Fill up relevant inspection recd sheet QA-A-03/QA-A-05.

    ROLLING:

    1. Check whether punch marks are there for frame lines/roll lines on the elementsto be formed.2. Check the template provided for its correctness by the data provided on the

    template.

    a. Mark the lines with the yellow chalk.3. Handle the plates carefully by hoists of the press and start rolling.4. Check the rolling with templates provided. HSL standards for rolling are to be

    ensured.

    5. After rolling is over the plates are to be stacked, so that deformation are to beensured.

    6. Fill up the inspection record sheet QA-A-04.

    DESPATCH/DELIVERY:

    1. Processed elements shall be binned panel/block wise and small componentsseparately.

    2. Processed elements shall be dispatched as per the PPCD schedule.

    Non-conformity-cum-resolution report (NCRR):

    If any item is found not conforming to drawing and standard, NCRR is to be raised

    through QUALITY CONTROL.

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    Q.C PROCEDURES AND DOCUMENTATION IN HULL SHOP:

    1. Inspection record sheet for plates and sections at treatment plant at hull shop isformat QA-A-01

    2. For the elements cut on CNC/plasma the inspection record sheet for elements atHull shop is Format QA-A-02.

    3. The elements cut as per plan for manual cutting will be inspected and recordedfor all the elements in the format QA-A-03

    4. Inspection record sheet for elements cut at hull shop is QA-A-04.5. Inspection record sheet for sections cut at Hull shop is QA-A-056. For dimension check of the template/ rolling set and knuckle set will be recorded

    in the format QA-A-06.

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    PRE-FABRICATION

    The cut elements, which are joined together to form a block or panel of the ship as

    per the structural drawings and designs through different welding processes.

    To joining these plates as per the grooves and edge preparation which are cut at Hull

    shop from previous stage the welding will be carried out in the form of grooves as per the

    required welding process(SAW, MIG,SMAW, MAG) and procedures by qualified welders with

    suitable selected electrodes and welding equipment.

    PRE-FABRICATION:

    pre-fabrication shops are existing adjacent to Hull shop at the side

    which consists of four areas A1, A2, A3 and A4 in two huge buildings consisting all

    required facilities and infrastructure arrangements to construct and fabricate blocks up

    to 150 tons in weight.

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    WORKING INSTRUCTIONS

    Scope: To Establish work instructions shall be a guide to all personnel in this

    department for performs Quality related activities.

    RESPONSIBILITIES:

    The Quality related activities and personnel responsibilities are given in the

    table hereunder..

    Quality related activity Responsibility

    Issue and control of drawings and material

    allocation

    Nominated person for this purpose

    Co-ordination of production activities for

    intending material schedule and other relevant

    inputs

    Officer-in-charge inE1/E2/E3 cadre in his area of

    operation

    Documenting results and generation of

    inspection records or production

    Respective supervisors/assistant supervisor of

    concerned

    Work Distribution Respective

    supervisors/assistant supervisor of concerned

    Execution of work Respective work-force

    Reporting of non-conformance or deviation from

    drawings

    Respective supervisors/assistant supervisors and

    above

    System:

    1. Manufacturing documents in the latest version as hereunder shall be referred in theproduction process

    2. Drawings.3. HSL Quality Standards4. Quality plan

    INSTRUCTION:

    MINI SUB -ASSEMBLIES:

    1. Identify the mini sub-assemblies in the drawing mark the elements of the sub-assembly.

    2. Align the tack the sub-assembly. Check for correctness as per drawing.3. Provide the adequate temporary supports to avoid distortion during welding .4.

    Complete welding and check for completeness and visual defects.

    5. Remove the supports and dress the mini sub-assembly.

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    LEVEL SKIN PANELS:

    1. Lay the plates on the level skid. Check the identity of the plates and to be done at Hullshop before processing the elements.

    2. Mark the reference lines for alignment.3.

    Align and tack the assembly.

    4. Check the overall dimensions of the skin panel.5. Complete the welding.6. Arrange the turning lugs for skin panel.7. Turn the skin panel.8. Dress the plate joints as necessary.9. Complete the sealing weld.

    SUB-ASSEMBLIES:

    1. Mark the skin panel for all the elements of the sub-assembly as per the drawing.Check for the dimensional accuracy as per the drawing.

    2. Erect in position elements, and mini sub-assemblies on skin panel with necessarysupports.

    3. Align the elements, Mini sub-assemblies on the skin panel and tack weld as per thedrawing.

    4. Check for alignments and then and release for welding.5. Dress the sub-assembly by removing the supports and check for completeness in all

    completeness.

    6. Remove the weld distortion if any.

    MAIN ASSEMBLY:

    1. Main assembly skin panel is identified for each panel/block in the drawing.2. The level skin panels and sub-assembly shall be fabricated as at 2 and 33. In case of panels/blocks having curvature,and panels being manufactured in natural

    position.

    4. Skid shall be prepared as per the data given in the drawing.5. Plates shall be laid on the skid prepared.6. Mark the plate reference lines for alignment.7. Align the plates and tack weld.8. Check for the dimensional accuracy of the skin panel9. Temporary clamps provided to skin panel and skid.10.Release for welding.

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    11.Complete the welding of the skin panel12.Mark the skin panel for the accuracy of the skid panel after welding and marking.13.Check for the dimensional accuracy of the skin panel after welding and marking.14.Erect in position the elements and sub-assembly providing with temporary supports.15.Align and tack the elements and sub-assemblies.16.Check for fit-up, alignment completeness of all elements and sub-assemblies.17.Offer for inspection.18.Upon satisfactory fit up,complete the welding.19.Turn the panel by providing lift and turning arrangement.20.Complete the scaling and welding.21.Inspect the weld joints for torsion.22.Rectify defects if any noticed.23.Dress the panel /block assembly24.Remove welding distortion25.Record the dimensional check sheet26.Inform QA NDT the completion of the welding of the panel.27.Rectify the defects if any reported in the radiography and inform(action by PFS

    welding).

    28.Offer for inspection for dry survey

    FABRICATION OF ASSEMBLIES OTHER THAN PANELS:

    1. Mark the elements of the assembly for alignment2. Align and tack the assembly as per drawing3. Provide adequate temporary supports to avoid distortion4. Check for fit up and alignment Complete the welding5. Dress the sub-assembly.6.

    Rectify the defects

    7. Fill in the conformation report

    PRESERVATION:

    Press ve the panel/blocks/assemblies by touching up the area paint is damaged.

    DISPATCH OF ASSEMBLIES:

    Dispatch the assemblies by appropriate handling available to other departments as per theinternal works order

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    ERECTION

    Hull berth department consists of three slipways each consisting of

    19526.6mts and 14022.7mts respectively and a covered building dock with

    intermediate gate facility of size 240531.25mts depth for a capacity of building ships

    up to 50,000 DWT. The building dock has two over head cranes, of which one is of 150

    tons capacity and the other is 100tons capacity. Adjacent to building dock there is a wet

    basin of size 22.5167.514mts depth where ships can be repaired and outfit works

    can be carried out while a floating vessels. There is a dry dock with a size of

    244381.6mts depth for the repairs of the ships up to 50,000DWT.

    There are cranes of capacities 45tons, 60 tons, and 100tons in between the

    building dock and berth and in between berths respectively.

    WORK INSTRUCTIONS FOR ERECTION:

    SCOPE:

    To establish work instructions which shall be a guide to all personal in this department

    for performing Quality related activities.

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    RESPONSIBILITIES:

    The quality related activities and personal responsible or given in the table hereunder

    Quality related activity Responsibility

    Issue and control of drawings Nominated person for this purpose

    Co-ordination of production activities for

    indenting material ,schedules, and other

    relevant inputs

    Officer-in-charge inE3/E2/E1 cadre in his

    are of operation.

    Documenting results and generation of

    inspection records of production

    Respective supervisors/assistant

    supervisors concerned.

    Work distribution --do--

    Execution of work Respective work force

    Reporting of non-conformance or

    deviation from drawing

    Respective supervisors./assistant

    supervisors and above.

    SYSTEM:

    1. Manufacturing documents in the latest version as hereunder shall be referred inthe production process.

    2. Drawings3. Material input from other department and stores.4. HSL quality standards.5. Quality plan

    INSTRUCTIONS:

    PREPARATION OF BERTH/BUILDING DOCK:

    The following reference lines are marked or grooved for total length of the ship to be

    built on the dock by berth shall be ensured:

    1. Centre line of berth/dock.2. Buttock lines one at the board and other at outboard to be grooved or marked

    parallel to central line

    3. Transverse line perpendicular to center line at least one in F.E. or in A.E. of eachpanel or at every tenth frame or as required

    4. These lines are the reference datum line for alignments5. Establish sighting line by sighting by theodolite on the stands provided at every

    tenth frame covering W.T. BHDS. On berth /building dock floor at convenient

    buttock line Nearest to centre line below 200 mm from the base line throughoutthe length of the ship.

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    ANCHORING POINTS:

    The anchoring points minimum 4 nos in athwart and 4 nos in longitudinal

    direction for datum panel shall be arranged in two nos in athwart direction for other

    panels.

    ERECTION OF PANELS:

    1. Ensure that the panel is cleared by class/owners from pre-fabricationdepartment.

    2. Adequate lifting or turning arrangement as per the concerned drawing beforeerecting the panel shall be ensured

    3. If any chain blocks are used the capacity and the distribution of load shall beensured

    4. The area or space is to be ensured for clear of all cables etc. before erection ofunits.

    5. Any staging required for erection of the panel shall be arranged prior to erectionof the panel for locking purpose

    6. The reference line such as buttock lines /frame/water lines before lifting shall bemarked on the panel

    ALIGNMENT OF DATUM PANELS:

    1. Datum panel is defined as the panel from which the growth of the vesselprogresses both ford aft and upward direction

    2. Datum panel immediately after erection on the keel or bilge blocks laid earlieras per drawing shall be tied with 8 rigging wires to the anchoring points firmly

    to the berth/dock by means of turn buckles.

    3. Datum panel centre line at tank top/ bottom shell be aligned and fixed withreference to centre line and frame line of berth or dock by means of plumb and

    rigging wires tied upon both FE and AE sides cross check with other buttock

    lines and frame lines the frame lines at FE/AE shall be aligned and fixed

    transverse lines marked on berth/dock (if it is berth declivity is to be

    considered while checking with plumb) by means of plumb and longitudinal

    rigging wires.

    4. The water level shall be checked at centre line longitudinally5. Athwart at AE middle and FE hydraulic jacks shall be used, Hydraulic jacks if

    any twist is found necessary concrete blocks are equivalent weights shall beused for a creep in case of loose decks

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    6. After ensuring all the requirements the data regarding frame line/buttocklines/water lines documented in the alignment check sheet.

    7. All the 8 rigging wires shall be tightened to prevent any further deviation. itshall be ensured that there is no deviation on the centre line of the unit a

    constant vigil of the datum unit is to be made by regular inspection.

    8. The lengths of panel shall be measured and recorded from AE frame of panelto AE frame of the next panel two contain the total length as per the HSL

    quality standards.

    HST PANELS:

    1. datum panel shall be selected so as to have maintained preferably within thepanel shall be supported by 2 nos of shores on FE/AE sides outside and two nosof wire ropes on AE and FE inside

    2. The panel shall be kept to correct buttock space from DB unit by means by turnbuckles on tank top through the corresponding frame line of DB on inboard side

    outboard point shall be plumbed to berth/dock and fixed in correlation to the

    plumb point

    3. The half bredth of panel is to be checked by dropping a plumb on outboard todock floor and corrected

    4. Panels on P and S shall be preferably aligned simultaneously5. Panel shall be conformed only after the final check of the breadth6. Water line at fore and after athwart direction shall be checked the same is

    counter checked by measuring the height of HST (top) from base line.

    7. Ensure 3 mm gap between floors quarters in way of seam to allow weldingcontraction of tank top and bottom shell seam. To allow welding contraction of

    tank top/bottom shell seam

    8.

    Panel shall be locked and dimensional data be documented on alignment checkformat

    HOLD BULK HEADS:

    1. The bhd shall be fitted with rigging wires of FE/AE sights before erection the eyesof rigging wire holding point sj=hall be fixed in such a way that the bhd can be

    adjusted to declivity or vertically as the case may be .

    2. Ensure adequate ribbons are provided to prevent any buckling while lifting &erection of Bhd ensure the working staging provided before erection of the panel

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    3. Bhd. shall be checked with the marking of centre a water level before erectionheight and breadth shall be checked with etc before erection at the top of the bhd

    remove the slings etc.

    4. Guiding flat bars of adequate scantling shall be provided on the ship so that thebhd. Shall be erected in the exactly right positions on the right frame line.

    5. The temporary stay wires shall be tied and tightened by means of turn buckle andvertically of the bhd to be checked by means of the plumb.

    6. The bulk head shall be aligned to buttock line or centre line. Frame line withreference to the buttock lines/center lines and frame lines of the DB below.

    7. The bhd. shall be aligned and water line shall be checked by water tube.8. The extrashall be marked to suit that water line adjustment on the athwart

    direction any error in DB panel shall be nullified here.

    9. BHD shall be lowered by cutting the extra as marked BHD shall be checked finallyfor frame line buttock line and waterLine with reference to DB and side shellpanels.

    10. Bhd. Shall be locked at side before tacking and all rigging wires are to bekept tight.

    T.S.T panels:

    1. The location and scantling of temporary pillars are to be designed for eachpanel.

    2. The temporary pillars are fitted as per drawing before lifting the panel3. Water line reference shall be marked on the part to TST unit4. Guiding members/flat bars shall be fitted on to the ship for the panel in order

    to erect the panel in correct position. The projecting lugs of main bhd.shall be

    cut off before lifting the TST panel.

    5. Panel shall be erected to correct frame line and plumb to correct buttock lines.6.

    Alignment of panels shall be started from the datum panels to be chosencoming in way of vertical bhd. And their succeeding intermediate panels(2

    nos) and DB panel at the centre shall be erected.

    7. The intermediate panels shall be aligned for frame line and buttock line withreference to tank to lines.

    8. The TST datum panel on Bhd. Shall be aligned holing to the integratedintermediate panels/UD.

    9. The panel shall be set to correct buttock line by dropping a plumb to the tanktop at FE and AE positions. Adjustments shall be made by means of turn

    buckles to

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    a) Integrated FE and TST panels andb)UD panel.

    10. The panel shall be set to frame line by dropping a plumb to tank top.11. Water line of panel at shell shall be set to bhd. FE and AE ends.12. After setting for frame line. Btk. Line and water line the panel shall be

    checked in positions.13. If any error in DB panel or HST regarding the water level the same shall be

    adjusted at the seam joint of shell and HST.

    14. The alignment shall be confirmed only when the other side (P&S) panel isalso set and half breadth shall be checked for both the panels.

    15. All TST units in way of hatch opening are aligned.16. The hatch measurements and the diagonals shall be checked. Any

    adjustments and the diagonals shall be checked. Any adjustment shall be made

    if necessary.

    INTERMEDIATE PANELS:

    1. The growth of DB shall be on both and aft direction from the datum panel.2. Before erection of the unit, the keel blocks and bilge blocks shall be ensured

    with correct height as per drawing and kept to water level on dock floor and

    ship declivity on berth by SWB dept.

    3. The unit shall be held outside to the panel that has already been aligned andlocked by means of 3 nos turn buckleson longitudinal and 1 or 2 nos cross

    wise.

    4. The free end of the unit to be aligned shall be fitted with 2 nos of wire onathwart direction to the anchor point on the dock or berth.

    5. The centre line of the intermediate panel shall be coincided with the centerline of the panel which was already aligned on one side.

    6. The centre line of the panel at the free end shall be plumbed to the centre lineof berth/dock and coincide by means of rigging wire and turn buckles

    anchored to dock or berth.

    7. The panel shall be set to correct frame space as per drawing at the centre lineand OBD buttocks on p/s by means of longitudinal turn buckles. Fitted to the

    panel which was already aligned.

    8. The overall length of panels shall be checked to the designed length anddiagonals shall be checked for squareness.

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    9. The water line of panel at longitudinal direction at the centre line from theframe line of previous panel at the panel joint to the extreme frame line of the

    panel shall be ensured

    10. The water line at athwart direction at the frame end shall also be checkedfrom centre line on a frame line. The water levels shall be ensured at the solid

    floors only.

    11. Variation in frame space/overall length. Buttock space and water levelsreferred thro NCRR and corrected according to the resolution. The overall

    length between the frame lines of main bhds . Shall be checked in order to

    have overall length of the ship to be within tolerance limits.

    ENGINE ROOM DOUBLE BOTTOMS:

    1. Special care shall be taken while aligning the ER area as any deviation in framespace of individual units may result for correction in accommodation area.2. The overall length of the engine room forward bulkheads to aft bhd shall be

    ensured for dimensional accuracies care shall be taken on this aspect for every

    panel joint in ER area as any deviation in frame space of individual unit s may

    result for correction in accommodation areas.

    3. The water line at free end of the panel shall be cocked down to take care of the liftat free end while welding the panel joint. The lift in the free end shall be

    monitored.

    4. The centre line deviation of ER DBs to berth/dock or ship centre line may effectthe shaft alignment. Cross wires provided to bottom shell on athwart direction to

    the anchoring points shall be kept Tight while welding and shall not be removed

    till all the welding works of joints are completed.

    5. Frequent monitoring shall be carried out.6. The line shall be sighted once in a month and any corrections shall be attended.7.

    The panel adjacent to A.P. unit shall be secured by means of rigging wires.

    a) 2no s on athwart directionb)2 nos vertically downward.PEAK PANELS:

    aft peak panels;

    1. Before the erection of A.P. panel the following shall be ensured.2. Keel sighting shall be confirmed and the reference imaginary line shall be

    extended to A.P. point for further reference.

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    3. The centre line of berth /dock shall be rechecked to centre line and extended toA.P. pointOn berths centre line shall be transferred to a rigid temporary platform

    ease of working in water front area.

    4. Any deviation of the adjoining free end of double bottom panel shall be corrected.5. The geometric centre point of stern tube casting shall be marked and punched at

    the ford &aft sides.

    6. The actual measurement of C.L of shaft from base line. Shall be taken at site fromthe keel sighting board at AE and FE of engine room.

    7. The guiding flat bars of adequate size shall be welded to bottom side of free endadjoining DB unit to enable erection of AP unit In right position at ford and

    matching to the bottom shell.

    8. Keel blocks shall be kept 15 mm lower than the designed height for easy erection.ERECTION OF AP PANELS:

    1. AP1 panel shall be lifted to correct declivity at berth or spirit level at dock.2. Panel shall be held by turn buckles on tank top and deck.3. After pulling to frame space equality on port & stbd. The gap for keel block to

    bottom of panel shall be filled up by SWB dept.

    4. Shores on the water front side or aft side shall be provided by SWB dept.5. After erection the shores shall be tied with ropes to shoring lug.6. The panel shall be tied by means of 2 nos .rigging wires on athwart direction to

    the anchoring points.

    ALIGNMENT FOR FRAME SPACE:

    1. The frame space at the panel joint shall be ensured as per HSL quality standardsand shall be made uniform at bottom shell level to IV deck(nearest deck) any

    angular deviation in frame space may lead to considerable error in super

    structure.2. Overall measurement of engine room shall be ensured along the shaft line.

    ALIGNMENT FOR CENTRE LINE:

    1. The centre line of the F.E. shall be coincided with tank top centre line by means ofcross turn buckle.

    2. A geometric centre point at A.E. shall be plumbed to dock or berth (temp.platform) and coincided by means of athwart rigging wires.

    3. As a final check the centre line of shaft be sighted by theodolite and checked.

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    ALIGNMENT OF WATER LINE:

    1. Initially the panel shall be aligned to water line by means of water tube on deck&shores below.

    2. The height of geometric centre point of at AE shall be checked from sighting lineand the designed height from base line shall be ensured.

    3. Final conformation shall be done by means of theodolite fitted ford of ME throughford & aft stern tube by keeping the seam at correct designed height at ford of

    ME & aft of stern tube.

    4. After alignment. The radial measurements of the theodolite to centering shall bedocumented for constant vigil while welding.

    5. The panel shall be held vertically downward at AE for following the unit to riseup at free end while welding the ford panel joint.

    CONCLUSION:

    1. Preparation of panel joint for full welding.2. Level and lock the joint with strong backs in way of stiffening members (without

    distributing the panel alignment).

    3. Edge preparation shall be done as per drawing/ HSL quality standards4. Root- gap to be maintained as per HSL quality standards5. Level and lock the plating and stiffening members of the panel joint.6. Proper size scallops are to be cut in the internal members coming in way of panel

    joint as well as in strong backs and locking pieces and ensure panel joint is free

    from rust, dust etc,,

    7. Fit up of the joint shall be offered to inspection authorities as per quality plan.8. Remarks If any, Shall be completed as recommended and release for full welding

    THE TEST PROCEDURE FOR THE ERECTION OR HULL BERTH DEPARTMENT:

    a. Leak testb. Hose testc. Pressure testd. Pressure test with air

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    Leak testing:

    It is determination of the rate at which a liquid or gas will penetrate from

    inside a TIGHT component or assembly to the outside, or vice versa as a result of a

    pressure difference between the two regions, or of permeation of a somewhat extended

    barrier it has become conventional to use the term LEAK to refer to an actualdiscontinuity or passage through which a fluid flowed through a leak. LEAK RATE

    refers to the rate of fluid flow per unit of time under a given set of conditions and is

    properly expressed in units of mass per unit of time.

    The term Minimum detectable leak refers to the smallest hole or discrete

    passage that can be detected and minimum detectable leak rate refers to the smallest

    detectable fluid flow rate.

    There are two basic types of leaksReal leaks and virtual leaks. A real leaks is

    an eccentrically localized leakthat is a discrete passage through which fluid may flow.

    Such a leak may take the form of a tube a crack and orifice. A system may leak through

    permeation of a somewhat extend barrier, this type of a real leakage called a

    distributed leak. Virtual leaks are leaks that involve the gradual description of gauges

    from surfaces are components within a vacuum system a vacuumed system may have

    both real leaks and virtual leaks simultaneously.

    HOSE TESTING:

    With help of fire tender water jet will be applied on weld joints with a pressure

    of 2.5 kg/cm2 keeping the water delivery nozzle tip 1.5m away from the testing job

    and simultaneously inspects other side of the job for any leakage of water, if leaks are

    found the same will be repaired .

    PRESSURE TEST:

    With hydraulically carried out by filling the water in the tank, space, voids, and

    keeping a water head in the top of the tank as required by the testing rules and inspects

    the for any leakage and soundness of the welds, as well as total integrity of the hull

    structure of the tankers space whether it is with standing the load or not for a specific

    time.

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    PRESSURE TEST WITH AIR:

    In this test process compressed air will be filled in the tank space void etc, and

    keeping a manometer other end of the tank and see that the pressure of the filled air

    comes to 0.145 bar head and observe the pressed tank for hours time after that

    outside of the tank joints will be inspected for leaks by applying soap water thus givesbubbles in case of any leakages, same will be repaired after releasing the air .

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    NON DESTRUCTIVE TESTING (NDT) METHODS

    Non destructive testing is a wide group of analysis techniques used in science

    and industry to evaluate the properties of a material component or system without

    causing damage. Because NDT does not permanently alter the article being inspected, it

    is a highly valuable technique that can save both money and time in product evaluation,

    trouble shooting, and research. Common NDT methods include, ultra sonic, magnetic,

    liquid penetrant, radiographic and Eddy current testing NDT is a commonly used tool in

    forensic engineering, mechanical engineering. Electrical engineering , civil engineering,

    medicine and art.

    NDT methods ma y relay upon use of electromagnetic radiation, sound, and

    inherent properties of materials to examine samples. This includes some kinds of

    microscopy to examine external surfaces in detail, although sample preparation

    techniques for metallographic, optical microscopy and electro microscopy are generally

    destructive as the surfaces must be made smooth through polishing of the sample must

    be transparent in thickness. The inside of a sample can be examined with penetrating

    electromagnetic radiation, such as X-rays or with sound waves in case of the ultrasonic

    testing contrast between a defect and the sample may be enhanced for visual

    examination by a unaided eye by using liquids to penetrate fatigue cracks one method

    LPT involves using dyce, florescent or non florescent, in fluids for magnetic materialsusually metals. Another commonly used method for magnetic materials involves a

    liquid suspension of fine iron particles applied to a part while it is in an externally

    applied magnetic field.

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    RADIOGRAPHIC TESTING

    PURPOSE: To ensure identity the internal welded joints defects on plating and section,

    pipe joints etc.

    SCOPE: This procedure shall be used for the detection of internal defects in welds

    SYSTEM:

    RADIATION SOURCE:

    Radiography will be performed with Ir-192gamma ray source.

    FILM IDENTIFICATION:

    Each radiograph shall be properly identified with nos and letters attached to the

    component during radiography.

    FILM DENSITY:

    The density of the radiography shall be between 2.0 t0 4.0 opt. densities

    TECHNIQUE:

    Single wall single image where possible.

    Double wall double image for jobs of OD up to maximum 89 mm

    Double wall, single image for jobs of OD more than 89mm and where single wall image

    is not possible.

    TYPE OF FILM:

    AGFA, Kodak, INDU or equivalent films with lead intensifying shall be used to achieve

    required quality radiograph.

    SENSITIVITY:

    Radiography shall be performed with a technique of radio sensitivity (2t) to display the

    essential wire of a wire type to QI.

    PROCESSING:

    Manual processing at controlled temperature

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    ACCEPTANCE STANDARDS:

    DEFECT TYPE PERMITTED MAXIMUM

    Under cut Slight intermittent under cut is permitted,

    provided the depth does not exceed0.5mm

    Shrinkage grooves/root concavities Slight Intermittent shrinkage grooves and

    concavities permitted to a maximum depth

    of 1.2mm

    Mis-alignment T/5 (up to 3mm max.)

    Cracks Not permitted

    Lack of root fusion --do--

    Lack of side wall fusion --do--

    Lack of inter run fusion --do--Lack of root penetration --do--

    Uniformly distributed porosity 2% by area of the weld.

    Slag individual and parallel weld axis L=T but not more than 25mm

    W=1.5mm max

    Slag linear group Aggregate length not exceed T in a length

    of 12T.

    T=plate thickness, L=length of defect, W=width of the defect

    ULTRASONIC TESTING

    Purpose: To ensure the materials/welded joints, sections etc. Are free from

    laminations &other discontinuities etc. in the sub surfaces.

    Scope: The procedure shall be used for the detection of laminations anddiscontinuities in welded joints, plates, sections etc.

    SYSTEM:

    SURFACE CONDITION: The surface shall be smooth and free from weld spatter ,

    surface irregularities, for the free movement of the probe.

    Equipment:Pulse echo (Kraut Krammer Usk-7)

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    TECHNIQUE:

    PLATES/SECTIONS:Back-wall echo technique with straight beam transducer.

    Welds: longitudinal and shear wave modes with straight and angle beam transducers.

    COUPLANT: Machine oil, glycerin, water, grease etc. shall be used as couplant

    SCANNING:

    PLATES/SECTIONS: scanning shall be continuous along the 225mm grid lines and on

    50mm path line from the edges.

    WELDS: scanning shall be performed on base metal adjacent to weld with straight

    beam probe. Scanning shall be performed with angle beam probe, directing the beamtoward the weld with a swivel of 5-10 degrees and with 108 overlap between

    successive scannings.

    ACCEPTANCE STANDARDS:

    WELDS:

    For examination of welds using a distance amplitude correction curve(DAC) any

    reflector which cause an indication in excess of DAC shall be investigated to the extent

    that it can be evaluated in terms of the acceptance standards of the reffering code

    sections.

    PLATES& SECTIONS:

    Any discontinuity indication causing a total loss of back reflection which cannot be

    contained with in a circle the diameter of which is 3 inches(75mm) or one half of the

    plate thickness whichever is greater is unacceptable shall be repaired and re-examined.

    MAGNETIC PARTICLE TESTING

    PURPOSE: To ensure the materials/welded joints/sections etc. are free from surface

    and sub-surface defects.

    SCOPE: This procedure shall be used for the detection of surface and sub-surfacediscontinuities in welds, plates, casting etc. of ferromagnetic materials.

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    SYSTEM:

    DESCRIPTION OF METHOD: This magnetic particle test method shall be applied to

    detect discontinuities on or sub surface ferromagnetic materials. This method involves

    magnetize the area to be examined and magnetic particles shall be applied on the area

    under the tests.

    SURFACE CONDITION:surface shall be clean dry and free from all dirt, scales, weelding

    flux, weld spatter, oil grease etc.

    MAGNETIZING APPRATUS:

    EQUIPMENT:PROD/YOKE Type

    Current: Half way DC/AC

    EXAMINATION MEDIUM: Magnetic particles black/red.

    EXAMINATION TYPE: dry or wet. For wet method: a suspension of 2t-2.5tsolid

    material by volume in kerosene or water.

    FIELD ADEQUECY: The field adequacy or the magnetic direction shall be checked by

    the field indicator.

    FIELD STRENGTH: For prod type ammeter reading shall be verified for yoke type by

    lifting the weight.

    EXAMINATION TECHNIQUE: The examination shall be conducted with over-laps and

    mutually perpendicular directions for full coverage. The test shall be carried out by the

    qualified persons and the results shall be evaluated by the level-II qualified persons.

    ACCEPATNCE STANDARDS:

    The surface to be examined shall be free from:

    Relevant linear indications.

    Relevant rounded indications greater than 5mm.

    Four or more relevant rounded indications in a line separated by 1.5mm or less(edge to

    edge)

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    LIQUID PENETRANT TEST

    PURPOSE: To ensure welded surface of plates , sections, pipes etc. is free from defects.

    SCOPE: This procedure shall be used for the detection of discontinuities opened to the

    surface in welds, plates, castings etc.

    SYSTEM:

    SURFACE CONDITION: Surface preparation by grinding, machining or other methods

    may be necessary where surface irregularities could mark the indications of the

    discontinuities.

    Prior to L.P testing, the surface of the plates has to be examined and all the adjacentareas within 25mm shall be dry and free from dust, dirt, grease, oil etc.

    Cleaning agents such as detergents, de scaling solutions and paint removers may be

    used.

    DRYING: After cleaning the surface to be examined visually and shall be allowed for

    drying.

    TECHNIQUE REQUIREMENT: As a standard technique, the temperature of thepenetrant and surface of the part are to be examined & shall not below 500F and above

    1250F.

    PENTRANT APPLICATION:

    The pentrant may be applied by brush or by spraying.

    The minimum penetrations time shall be 5minitues.

    EXCESS PENETRANT REMOVAL: After the penetration time the excess penetrant

    remaining on the surface shall be removed with a cloth the surface shall be cleaned by

    wiping with solvent moistened cloth care shall be taken to avoid the removal of

    penetrant from discontinuities.

    WORKING PRINICIPLE:LPT inspection depends mainly on a penetrants effectively

    wetting the surface of solid work piece or specimen, flowing over that surface to form a

    continuous band reasonably uniform coating and then migrating in to cavity that is

    open to the surface.

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    The ability of a given liquid to flow over a surface and enter surface cavities depends

    principally on the following factors.

    Cleanliness of surface- dirt, oil, grease, covers openings of flaws

    Cleanliness of the cavity-m improves surface tension properties, increases wetting

    effect

    Size of surface opening of the cavity

    Ability of the liquid to wet the surface which is closely related to phenomenon of

    capillary raise or depression.

    ACCEPATNCE STANDARDS:

    The test shall be carried out by qualified persons and the results shall be evaluated by

    level-II & Level-III qualified persons only.

    The surface examined shall be free from:

    Relevant linier indications

    Relevant rounded indications greater than 5mm.

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    CONCLUSION

    This is a great opportunity for us to undergo in Shipyard for the project work . During

    the project work we have come across various technical and engineering aspects andwe are enlightened due to the dissemination of the knowledge and information about

    the ship construction by various technical aspects.

    We have observed the mission and values of Hindustan Ship

    Yard executives in an hierarchical way are highly innovated standard of the

    organization which is the quite draining force of the yard functioning

    We proposed to add to this colossal organization as a drop in

    an ocean that the systems and procedures that working in each area should be exposed

    to lower level for exposition of employees involved in every area in order to shift the

    responsibilities of the top executives to middle management as well as down level in

    the staff and workmen.

    .


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