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provisionsfordangerousgoodslimitingtheapplicationofChapterVItoaspectsnotcoveredi n C ha pt er V II . A pp li ca ti on o f t he n ewRegulationstodangerousgoodsissimilarlylimitedtoaspectsnotcoveredintheMerchantShipping (Dangerous Goods and MarinePollutants)Regulations1997.

Cargoinformation

5. The cargo information required to beprovidedbytheshipperinaccordancewithreg.4maybeconvenientlypresentedto theoperatororthemasterusingtheformatannexAtothisNoteextractedfromIMORes.A.862(20).Itmay be noted th at the form is no t app lic ab le top ac ka ge d d ang er ou s g oo ds r eq ui ri ng adangerousgoodsdeclarationinaccordancewithreg.10oftheMerchantShipping(DangerousGoodsandMarine Pollutants)Regulations1997.

Asanaidtoreducingpaperdocumentation,ElectronicDataProcessing(EDP)orElectronicDataInterchange(EDI)methodsmaybeusedforprovidingtheinformation.

Oxygenanalysisandgasdetectionequipment

6. Reg 7(1 ) r equi res the pr ovi si on ofinstruments for oxygen analysis and gasdetectionwhencarryingbulkcargoesliabletoemittoxicorflammablegasesorcauseoxygendepletioninthecargohold.Ship’sstaffshouldbefamiliarwiththeuseoftheinstrumentswhichsho ul d b e r eg ul ar ly u se d d ur ing c ar gomonitoring.Theinstrumentsshouldberegularlyservicedandcalibratedinaccordancewiththemanufacturers’instructions.

Loading/Unloadingofbulkcargoesotherthangrain

7. Shipscarryingbulkcargoesarenormallyprovidedwithapprovedstabilitybookletsandloadingmanualswhichshouldalreadymeettherequirementsin reg.10(2)ontheprovisionof a

cargoloadingmanual.Intheeventofanydeficiency,ownersandoperatorsshouldprovidethe necessary additional information forcomplianceassoonaspossible.

8. Intheinterestsofsafetyclosecooperation betweentheshipandtheterminaliscalledforonallmattersrelatingtoloading/unloadingofbulkcargoes.The“CodeofPracticeforSafeLoadingandUnloadingofBulkCarriers”,publishedbytheInternationalMaritimeOrganisation(IMO

SalesNo.266E), maybereferred tofordetailedoperational guidance, including theresponsibilitiesofthemasterandtheterminalrepresentativeinthecargooperations. TheCodewas developedin the IMOon thebasisofwhatwasrecognisedasa standardofgoodpracticeinthe industry. Although the Code is notmandatory,itisexpectedthattheCodewillbe

followedbyallterminalsandshipsthroughselfregulation.

9. Reg.10(3)requirestheloading/unloadingplanandanysubsequentamendmentsagreed be tween the ma st er and the te rminalrepresentativetobelodgedwiththeappropriateauthorityoftheportState.Reg.10(1)(b)providesthatintheUKtheappropriateauthorityistheHarbourAuthorityoftheportorinthecaseofaterminalnotoperatedby theHarbourAuthorityof the area, the operator of the terminal.

Informationonthedesignatedholdingpointsfordepositingtheagreedplans/amendmentsshouldbeincludedintheinformationontheterminal providedto themasteronor beforearrival.Itshouldbenotedthatnocargoloading/unloadingistobecommencedbeforetheplanisagreedandsignedby both themasterandtheterminalrepresentative.Themastershouldarrangefortheagreedplans/amendmentstobedepositedatthedesignatedholdingpointsandmakeanentryintheship’scargologbooktothateffect.

10. Themasterandtheterminalrepresentativearedeemedcompetentwithintheirareasofresponsibilityundertheloading/unloadingplanandit isnotintended that the agreed planshould be subject to any approval by thereceivingauthorityintheportorathirdparty.Informationcontainedintheplansshouldbetreated by the receiving authority ascommerciallysensitivetobereleasedonlywhenrequested understatutoryauthority. Theplanandanyamendmentstoitshouldberetainedbythemaster,theterminalrepresentativeandthe

receivingauthorityforaperiodofsixmonths.Duringthecargooperations,whenthereisadisagreementordisputeaffectingsafety,MCAand/orHSEaretobeinformedasappropriatefollowingcurrentpracticeforsimilarsituationsinport.

11. Reg.10(4)requiresthemastertoensurethatthe cargo is trimmed reasonably level, asnecessary.Anyrequirementsfortrimmingshould be in accordance with Sect ion 5 :TrimmingProceduresofthe“IMOCodeofSafe

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PracticeforSolidBulkCargoes”(BCCode)(IMOSales No260.E). Provisions for adequatetrimmingshouldbeagreedaspartoftheloadingplan.

12. Reg.10(7)(c)providesthatthemasterandtheterminalrepresentativeshallensurethattheunloadingmethoddoesnotdamagetheship’s

structure.Theterminalshouldmakeeveryeffortto avoid damage to the ship when usingunloadingorholdcleaningequipment.Ifanydamageoccurs,thisshouldbereportedtothemaster.

13. Whenloadingcargoessuchasscrapmetal,specialcareshouldbetakenparticularlyatthestartofloadingineachcargoholdtoavoiddropsofheavyloadswhicharelikelytocausedamagetothetanktopstructure.Initialloadingintheholdshouldconsistofsmalleritemsuntilthe

tanktopiscoveredtoareasonableheight.Highfreefalldropsofheavyconcentratedloadsshouldbeavoidedatalltimes.

14. I t is desirable that cargo spaces areinspectedbytheship’sstaffandtheterminalpersonneltakingpracticallimitationsintoaccountbeforeandafterloading/unloadingoperations.Referenceshouldbemadeto IMORes.A.866(20):“GuidancetoShip’sCrewsandTerminalPersonnelforBulkCarrierInspections”atannexBtothisNote.

15. Anydamageaffectingtheseaworthiness,structural integrity or the ship’s essentialengineeringsystemsetc.shouldbereportedtothe ClassificationSociety, the flag stateand theportstate(SOLASRegI/11(c)refers).

Smallvessels,dredgersetc.

16. ItistobenotedthattheRegulationsapplytoallseagoingvesselscarryingcargoeswithoutanylower l imit . In the case of small vessels ,particularlythosehavingsingleholds,the

proceduresshouldbesimpler.Neverthelessfactorssuchasthedepthofwater,natureofthecargoandthedegreeof trimmingmaybesignificantandtheproceduresshouldbefollowedtoensurethatthevesselisfittoproceedtoseaafterthecargooperations.

17. Inthecaseofsmallshipsengagedinanumberoftripsunderidenticalconditions,thecargoloading/unloadingplanmaybeprepared

coveringmultipletripssubjecttoscrutinyperiodicallyorwhentheconditionschange.Thiswillapplytodredgerswhichareoftenengagedinrepeatedtripsbetweenthesamedredgingsiteandunloadingshoreterminalwheretheterminalcontrolstheunloading.Wherethedredgerisaselfunloader,orwheretheshipdredgesachannelanddumpsthespoilatsea,themaster

andthe“terminalrepresentative”areineffectoneandthesame.Recallingthattheintentionoftheloadingplanistoensurethattheshipsailsonlyinanundamagedandsafeloadingconditionafterloadingorunloadingoperations,therewillbenoseparatepartiesto aloadingplananditwillbesufficientfortheownerandmastertoensurenormalsafeoperatingpracticesinaccordancewiththeship’sloadingmanualandinformationonthedredgedmaterial.Wherealoadingplancoveringmultipletripsisagreedbetweenthemasterandaterminal,itshouldbelodgedwith

theHarbourAuthority.

March1999

MSPP2MaritimeandCoastguardAgency

SpringPlace105CommercialRoadSouthamptonSO151EG

Tel 01703329176Fax 01703329204

(MS10/25/037(4))

©Crowncopyright1999

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Shipper Reference number(s)

Consignee Carrier

Name/meansoftransport

Port/placeofdeparture

Instructionsorothermatters

Port/placeofdestination

Generaldescriptionofthecargo Grossmass(kg/tonnes)

(Typeofmaterial/particlesize)*

GeneralcargoCargounit(s)

*Forsolidbulkcargo Bulkcargo

Specificationofbulkcargo*StowagefactorAngleofreposeTrimmingproceduresChemicalproperties ifpotentialhazard

*Ifapplicablee.g.,IMOclass,UNNo.orBCNo.andEmSNo.

Relevantspecialpropertiesofthecargo Additionalcertificate(s)*CertificateofmoisturecontentandtransportablemoisturelimitWeatheringcertificateExemptioncertificateOther(specify)

*ifrequired

DECLARATION

Iherebydeclarethattheconsignmentisfullyandaccuratelydescribedandthatthegiventestresultsandotherspecificationsare correct tothe best of myknowledge and belief and can be considered asrepresentativeforthecargotobeloaded.

Name/status,company/organisationofsignatory

Placeanddate

Signatureonbehalfofshipper

AnnexA

Formforcargoinformation(Recommendedlayout)

Note: This form is not applicable if the cargo to be loaded requires a declaration under the requirements of SOLAS1974, chapter VII, regulation 5; MARPOL 73/78, Annex III, regulation 4; and the IMDG Code, General Introduction, section 9.

❒

❒

❒

✝

✝

❒

❒

❒

❒

Asanaidtopaperdocumentation,ElectronicDataProcessing(EDP)orElectronicDataInterchange(EDI)techniquesmaybeused.

This form meets the requirements of SOLAS 1974, chapter VI, regulation 2;the BC Code and the CSS Code.

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AnnexB

ResolutionA.866(20) Adopted on 27 November 1997

(Agenda item 9)

GUIDANCETOSHIPS’CREWSANDTERMINALPERSONNELFORBULKCARRIER

INSPECTIONS

THEASSEMBLY,

RECALLINGArticle15(j)oftheConventionontheInternationalMaritimeOrganizationconcerningthefunctionsoftheAssemblyinrelationtoregulationsandguidelinesconcerningmaritimesafety,

RECALLINGFURTHERthat resolution A.797(19)urgesshipowners,shipoperators,shipmasters andterminaloperatorstotakeimmediatemeasuresasspecifiedintheannexthereto,includingmeasuresforshipownerstoimplementaplannedmaintenanceschemeandtoconduct“owners’surveys”ofcargoholdsbefore loading andafterunloadingandmaintainonboarda logofthese surveys, and thatterminalpersonnelareawareofareasofspecificconcernrelatingtoloadingandunloading,

RECALLINGALSOthatresolutionA.744(18)requirestheshipownertomaintainonboarddocumentationrelatingtoinspectioncarriedoutbyship’spersonnelwithrespecttostructuraldeteriorationandtheconditionofthecoating,ifany,

BEINGCONCERNEDatstructuraldamagesinflictedonshipscarryingsolidbulkcargoeswhichareoneofthecausesoftheconsiderablenumberofbulkcarrierlosses,sometimeswithouttrace,andtheheavylossoflifeincurred,

HAVING CONSIDEREDtherecommendationmadeby theMaritimeSafety Committeeat itssixtysixthsession,

1. ADOPTStheGuidancetoShips’CrewandTerminalPersonnelforBulkCarrierInspections,setoutintheannextothepresentresolution;

2. INVITESGovernmentstobringtheGuidancetotheattentionofshipowners,shipoperatorsandshipmastersofshipsentitledtoflytheirflagaswellastoterminalpersonnelconcerned,andtourgethemtoimplementitasappropriate;

3. REQUESTStheMaritimeSafetyCommitteetokeeptheGuidanceunderreviewandamendorextendit,asnecessary.

Annex

GUIDANCETOSHIPS’CREWSANDTERMINALPERSONNELFORBULKCARRIERINSPECTIONS

1 PURPOSE

1.1 Thisdocumentisintendedtoprovideguidancetoship’screwandterminalpersonnelwithrespecttotheprincipalareasonbulkcarriersthatarelikelytobesusceptibletocorrosionordamage.

1.2 UndertheGuidance,itisconsideredtheresponsibilityoftheownertomaintainand,wherenecessary,reportondeficientconditionsfound,togetherwithanyrepair(s)carriedout.Thisdocument

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isintendedtoprovideguidancetopersonnelnotexperiencedinconductinginspections.Tofacilitateeffectivedischargeofthisresponsibilityandrecognisingthenormaldutiesofships’crewandterminaloperators,ithasbeenthoughtdesirabletoprovidethemwithasimpleguidethatexplainstheareasofprincipalconcern.

1.3 Inthisconnection,itshouldbeunderstoodthattheship’screwandterminaloperatorsmaynot bequalifiedintheinspectionofships. ItshouldalsoberecognisedthatsuchinspectionscannotinanywayreplacesurveysconductedbyflagStatesorrecognisedorganisationsactingontheirbehalf.

1.4 Thisdocumentisalsoconsideredasanappropriatebasisforassistingintheimplementationofaneffectiveprogrammetomaintaintheshipinasatisfactoryconditionbetweentherequiredperiodicalsurveys.

2 INTRODUCTION

2.1 Responsibility forperformingperiodicalinspectionofthe hull structure ofbulkcarriersinaccordancewiththeEnhancedSurveyProgramme(ESP)restswiththeflagAdministrationorrecognisedorganisation.

2.2 Itisimportanttorecognise,however,thatseverestructuraldamagemayoccurtobulkcarriersdueto loading/unloadingoperations.Suchdamage may occur instantly,andmay,in severecases,

endangertheship’ssafetyunlessrectifiedrapidly.Furthermore,minorcracks,whichhavebeenundetectableatagivenESPsurvey,maydevelopintoseriousdefectspriortothenextESPsurvey.

2.3 Inviewofthis,it isrecommendedthatterminaloperatorsandmembersoftheship’screwthemselvesregularlyinspectthecargoholds,hatchcoversandballasttankswithaviewtodetectingdamageanddefects.ESPdocumentationshouldbeusedasguidanceonspecificpartsofthestructureneedingparticularattentioninindividualships.

2.4 Fromasafetypointofviewitisdesirablethatinspectionsofcargoholdsbytheship’screworterminaloperatorsareconductedbefore allloadingandafterallunloadingoperations,althoughpracticallimitationswillhavetobetakenintoaccount.

2.5 Tomaximizetheeffectofsuchinspectionsbyship’screworterminalpersonnel,anappropriatelog ofsuchinspectionsshouldbekept onboard.For inspectionsperformedbytheship’s crew,it isrecommendedthattheform“Owner’sInspectionReport”incorporatedinresolutionA.744(18)onESP beusedforthispurpose,andmadeavailableforsurveyorsfromtheflagAdministrationorrecognisedorganisation.Thisreportwillalsoassisttheshipownerindevelopingthesurveyprogramme,inco-operationwiththeflagAdministrationorrecognisedorganisation,whichisrequiredbySOLAS.

3 GENERAL

3.1 Abulkcarrierisacargoshipdesignedandbuiltforcarriageofdrybulkcargoessuchasgrain,coal,ore,etc.Thecargoholdstructurewithtopsidetanksatbothshouldersanddoublebottomswithhoppersatbothwingshasbeendesignedasthebeststructurefordrybulkcargotransportation.Theshapeoftopsidetanksprovidessufficientstabilitytopreventdangerouscargoshift,andbilgehopperscontributetoconvenienceincollectingthecargoesondischarge.

3.2 Inadditiontolightbulkcargoes,coalandorearethemaincargoescarried.Coalandlightbulkcargoesarestowedineverycargohold.Ironore,however,isusuallyshippedinalternatecargoholds becauseofitshighspecificgravity.Thisisdoneforthepurposeofavoidingexcessivelystiffshipmotionandalsofortheconvenienceofloadingfacilities.

3.3 Ondesigningabulkcarrier,loadingpatternsandsequencesreflectingthespecificgravitiesofintendedcargoesandballastingpatternsinvariousoperationmodesaretakenintoconsideration.Thesedesignconsiderationsaredescribedinloadingandoperationmanualswhichprovideshipofficerswith basicloadingpatterns,strengthfeaturesandlimitationsoftheship.

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4 DEFINITIONSANDTERMINOLOGY

4.1 Bulk carrier:abulkcarrierisacargoshipintendedforcarriageofdrybulkcargoessuchasgrain,coal,ore,etc.,providedwithtopsidetanksatbothshouldersandbilgehoppersinbothdoublebottomwingsinthecargospace.Belowisatypicalmidshipsectionandgeneralarrangement.

Midshipsection

Generalarrangement

Figure1 Typical midship section and general arrangement

4.2 Topside tank :tanksprovidedincargospacesatbothshoulders,asthespace(1)showninthedrawingabove.

4.3 Bilge hopper:aconventionalbulkcarrierhashopperstructuresatbothbottomwingsincargo

holds.Thispartofthecargoholdiscalledthe‘bilgehopper’.Doublebottomtanksinwayofbilgehopperareoftencalled‘bilgehoppertanks’.Inthediagram,thespaceisshownas(2).

4.4 Girder and floor in double bottom:providedindoublebottomtanks,‘girder’usuallyindicatesastrongframe,usuallywiththefulldepth,providedinship’slongitudinaldirection.Thegirderfittedonthecentrelineiscalled‘centregirder’,whiletheothersarecalled‘sidegirders’.’Floor’meansstrongframinginship’stransversedirectionprovidedin doublebottom.Indoublebottom beneathcargoholds,floorplatesareusuallysolidoneswithfulldepthofthetank.Inthisregard,solidonesarecalled‘solidfloors’asdistinctfromtheothers.

4.5 Transverse web in topside tanks:strongframingprovidedintopsidetanksinthetransversedirection,alsocalled‘transversering’.Ofatransverseringinatopsidetank,thepartsupportingtheupperdeckiscalled‘decktransverse’,thepartattachedtothesideshelliscalled‘sidetransverse’andthepartattachedtothebottomiscalled‘(topside)bottomtransverse’.

4.6 Transverse web in bilge hopper tanks:strongframingprovidedinthetransversedirectioninabilgehoppertank.Transversewebsarecalled‘bilgehopper transverse’, ‘side transverse’ and‘bottomtransverse’inaccordancewiththenameofthehullmemberstowhichtheyareattached.

4.7 Framing of various kinds:onatypicalbulkcarrier,framingisdesignedasalongitudinalsystemintopsideanddoublebottomtanksandasatransversesystematcargoholdsideshell.Framingfittedinship’slongitudinaldirectionarecalled‘longitudinals’.Toidentifythemindetail,thenameoftheplatetheyareattachedtoisadded,suchas‘decklongitudinals’,‘sidelongitudinals’,‘bottomlongitudinals’,etc.Framingattachedtothesideshellinthecargoholdsarecalled‘holdframes’,‘sideframes’,‘mainframes’,’shellframes’,etc.

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Figure2- Typical cross-section of cargo ship (bulk carrier)

5 GROUPINGOFBULKCARRIERSACCORDINGTODIMENSIONS5.1 Ingeneral,bulkcarriersaregroupedintothreecategoriesaccordingtosize.Theseare:capesize,panamax,andothersmallertypes.Amongthesmallertypes,shipsof30,000to45,000dwthavingfivecargoholdsarecalled‘handybulkers’.Panamaxbulkersarebulkcarriershavingabreadthof32.2m,andarethelargestshipsabletotransitthePanamaCanal.Shipsofthiskindusuallyhavesevencargoholdsandadeadweightofaround50,000to60,000tonnes.Bulkerswithdimensionsgreaterthanthepanamax shipsarecalled ‘capesizebulkers’.Capesizebulkershavenineormorecargoholdsandadeadweightinexcessof100,000tonnes.

5.2 Capesizeandpanamaxbulkcarriersaregenerallyengagedincarriageofrawmaterialsforindustrialplants,suchascoalandironore.Smallerbulkcarriersandsomepanamaxonesaregenerallyengagedin thetradeofgrain.Lumberandindustrialproductsaregenerallyshippedbyhandysizeorsmallerbulkers.

Figure3- Various bulk carriers

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5.3 Inthetradeoffoodresourcessuchaswheat,corn,andlumber,unloadingportsusuallyhavenocargohandlingfacilitiesandthebulkcarriersemployedareoftenequippedwiththeirowncargogear,whilepanamaxorcapesizebulkcarriersaregearless.

6 STRUCTURALFEATURESANDTYPICALDAMAGE

6.1 Upperdeckareas

6.1.1 Thelongitudinallycontinuousupperdeckofabulkcarriersuffershullgirderstress.Thelongitudinalbendingcausesanaxialforceontheupperdeckthatmaycausecrackingofthedeckplateatthelocationswherethestressisconcentrated.

6.1.2 Bulkcarriershavecargohatchwaysfor theconvenienceofcargohandlingfacilities. Thesehatchwaysreducetheship’storsionalstrengthandinviteconcentratedstressatthehatchwaycornerswhichmaybeevidentbycrackingofthedeckplatesintheseareas.

6.1.3 Crossdeckstripscomeunderstressbytransversebending.Thetransversebulkheadsprovidetransversestrengthtoabulkcarrierandthecrossdeck stripsprovidethe strengthtowithstandtheresultantaxialforcesinatransversedirection.

Figure4- Check points on the upper deck

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Deformation

Buckling of cross-deck strips6.1.4 Generally, longitudinalbeamsarearrangedunderthe longitudinallycontinuousupperdeckoutboardofthesidelinesofthecargohatchways.Thisiscalledthelongitudinalsystem.Whenthedeck beamsforcrossdeckstripsarealsoarrangedinthismanner,bucklingofthecrossdeckstripsmaytakeplaceduetoinsufficientstrengthagainsttheaxialforcesactingonthemina transversedirection.Thetransversesystemisthepreferredmethodofconstructionforcrossdeckmembers.Particularattention

shouldbegiventobucklingofthemaindeckonthoseshipswherethecrossdeckstripsarearrangedinthelongitudinalsystem.

Figure5- Comparison of stiffening systems for cross decks

Cracking

6.1.5 Therearevarioustypesofcrackingintheupperdeck.Thosepropagatingfromthecargohatchwaysaregenerallyconsideredserioustotheship’ssafety:

.1 Hatchway corners

Thelargecargohatchwayopeningsreducethetorsionalstrengthofthehullandinvitestressconcentrationattheircornersontheupperdeck.Inthisregard,upperdeckplatingathatchwaycornersisoneofthefocalpointsforcracking.Particularattentionshouldbepaidtotheseareasduringinspection.

Figure6 - Cracking at hatchway

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.2 Upper deck plating at deck fittings

Variousmetal fittingsareweldedto theupperdeckplating.These installationsmay causestressconcentrationsattheweldedjointsorhavedefectsinthewelds.Deckplatingsinthevicinityofmanholes,hatchsidecoamingendbrackets,bulwarkstays,cranepostfoundationsanddeckhouses,etc.aretobecarefullywatchedforcracking.

Figure7- Various crackings in upper deck plating

.3 Hatch coamings

Hatchcoamingsaresubjectedtohullgirderstress.Althoughtheyarenotcriticallongitudinalstrengthmembers,theyshouldbewatchedcarefullytoensurethatthesecracksdonotspread.Crackingmaybeinitiatedatdefectsinweldedjointsandmetalfittingstothecoamingsthatwillinvitestressconcentration.Suchcrackingisconsideredserioustotheship’ssafetybecauseitmaybetheinitiationofafractureonalargescale.

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Figure8 Cracking in hatch coaming

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Corrosion on deck

6.1.6 Thinnersteelstructuresondeck,suchascrossdeckstrips,hatchcoamings,hatchcovers,etc.,areeasilycorrodedandoftenholed.Thebestwaytodetercorrosionistokeepthestructurewellcoatedandpainted.Thepartsmostliabletocorrosionintheupperdeckareaareasfollows:

.1 Cross-deck strips

Thethicknessofcrossdeck platingbetweenhatchwaysis designedaboutahalfofthatofmainstrengthdeckplatingbecauseitisnotalongitudinalstrengthmember.However,crossdeckstripsprovideanimportantpartofthetransversestrengthoftheship,andcorrosionandwasteofthecrossdeckplatingmaybeconsideredserioustotheship’ssoundness.

L (m) Atmaindeckplating Atcrossdeckstrip

Handybulkcarrier 177.00 17.5mm(32H/T) 10.0mm(MS)

Panamax bulkcarrier 215.00 20.5mm(36H/T) 10.5mm(MS)

Capesizebulkcarrier 280.0 33.0mm(40H/T) 12.0mm(MS)

Figure9 Examples of comparison of thickness of main deck and cross deck

.2 Hatch covers

Thethicknessofhatchcoversisapproximatelythesameasthatofcrossdecks.Holesinhatchcoverscausedbycorrosionleadtowateringressincargoholds,whichmayleadtoshiftingofcargoand/orproblemswiththestabilityoftheship.

.3 Hatch coamings

Whensteampipesarearrangedbesidehatchsidecoamings,thecorrosionprogressofthe

coamingisveryrapid.Corrosionholesofthecoamingplatesleadtothesameproblemsasthoseassociatedwithhatchcovercorrosion.

.4 Weather tight doors, small hatches and wall ventilator covers

Notonlycovers,doorplatesandcoamingsbutalsohinges,gasketsandclipsaretobealwayskeptingoodcondition.

.5 Standing pipes on deck

Ventandsoundingpipesfromwaterballastorfueloiltanksandventilationpipesforclosedspacesundertheupperdeckareliabletocorrosion.Ifthesepiecesbecomeholed,seawatercomesdirectlyintothetanksorcargoholdsandmaycausecontaminationoffueloil,cargo

damage,shiftingofcargo,and/orstabilityproblems.

.6 Forecastle aft wall

Thebilgesinforecastlespacemaycausecorrosionofthebulkheadwhereitmeetsthedeck.Influshdeckedbulkcarriers,theboatswainstoreaftwallmaybecorrodedinthesamemanner.Largebulkcarriersgenerallydonothaveforecastleandhavetheirboatswainstoresdown belowtheupperdeckinforepeakspaces.BilgesleftinsuchspacesalsocausecorrosionoftheaftendbulkheadwhichseparatesboatswainstoreandNo.1cargohold.Suchwastagemayleadtowateringress,cargodamage,cargoshifting,and/orstabilityproblems.

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9 7 5 3 8

Figure10 Forecastle end bulkhead

6.2 Cargoholds

Structural features

6.2.1 Ontypicalbulkcarriers,thetopsideandbilgehoppertankscomposeadoublehullsurrounding

the cargospace,which togetherwiththedoublebottomprovideshull strengthandrigidity.Singlehulledsideshellsprovidedwithindividualtransverseframesarelocatedbetweenthetopsideandbilgehoppertanks.Inrecentdesigns,theseholdframesandendbracketsarethinnerthanthesideshellandarenotconstructedwithwebframesandsidestringers,asisthecasewithgeneralcargocarriers.

Belowisacomparisonofthicknessofhullskinplatesandholdframesincargohold.

Tanktop(mm)

Holdframe(mm)

Sideshell(mm)Web Face Endbracket

HandyBC 15.0(MS) 9.0(MS) 12.0(MS) 10.0(MS) 12.5(MS)

PanamaxBC 17.0(MS) 10.0(36HT) 12.5(36HT) 11.0(36HT) 15.5(32HT)

CapesizeBC 18.5(36HT) 10.0(36HT) 17.0(36HT) 12.0(36HT) 17.5(32HT)

Figure11 Comparison of thickness of hull skin and hold frames

Corrosion and waste of hold frames

6.2.2 Corrosiongenerallyattacksthinnersteelstructuresandisacceleratedinthinnerplates.Inthetimeathickersteelplateloseshalfofitsoriginalthicknessathinnerplatemightcorrodecompletely.

6.2.3 Amongthevariousmemberscomposingcargoholdstructures,theholdframesareusuallythethinneststructures,especiallyatthewebplates.Inaddition,theholdframesalsohavemoresurfaceareaexposed,inthatbothsurfacesoftheplatearesusceptible.

6.2.4 Thismaymeanacceleratedcorrosionintheholdframes,thethinnestamongall themembersincargoholds.Ifcorrosionandwastebecomeexcessive,failureofholdframesinvitesadditionalloadstotheadjacentones,whichmayleadtofailurethroughoutthesideshellstructure.

6.2.5 Transversebulkheadsmayalsobesusceptibletoacceleratedcorrosion,particularlyatthemidheightandatthebottom.Particularcareshouldbeexercisedwheninspectingholdframesandtransversebulkheads,in that thesemembersmayappearindeceptivelygoodcondition.Tanktopandsideshellplatinggenerallycorrodesfromthesteelsurfacefacingthecargoholdandcorrosionfrominsidethedoublebottomisusuallylessthanthatfromthecargoholdside.

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9 7 5 3 9

Figure12 An example of a corroded hold frame

6.2.6 Regardingthecorrosivenessofcargoes,coalisamongthemostcorrosiveofcargoescarriedon board bulk carriers. Thicknessmeasurement surveys reveal that bulk carrierswhich have beenemployedincarriageofcoalsuffermoreseriouscorrosiontotheircargoholdsthanthoseengagedinthecarriageofanyothercargoes.

6.2.7 Cargoholdframesshouldalsobecarefullyinspectedformechanicaldamage,corrosionandwaste,becausemanycargoeswilldamageholdframesthroughdirectcontact.Thisdamagewillinvite

corrosionfromseawaterbroughtonboardinloadingoperations.

6.2.8 Themostimportantaspectsofcargoholdinspectionsaretheconditionofsideshellstructuresandtheirreinforcements.Specialattentionshouldbepaidtotheconditionofholdframesandtheirconnectiontotheshellplating.

Transbulkheads and associated structures

6.2.9 Bulkcarrierwatertighttransversebulkheadsattheendsofdrycargoholdsareconstructedinvariousways,whichingeneralcanbecategorisedaseitherverticallycorrugatedwithorwithoutupperorlowerstools, doubleplatedwithor withoutupperorlowerstools,orplanebulkheadsverticallystiffened.

6.2.10 Itmaybenecessarythatcertainholdsboundedbytheforegoingcategoriesofbulkheadsarepartiallyfilledwithwaterballastinordertoachieveasatisfactoryairdraughtattheloading/discharge berths.The fillingis restrictedtocorrespondtothedry cargoholdscantlings.However,fordeeptankcorrugatedbulkheadsattheendsofcargoholdswhicharedesignedtobefullyfilledwithwaterballast,thescantlingsareincreasedsubstantiallyfromthatforordinarywatertighttransversebulkheads.

6.2.11 Theopportunityis takento emphasise that forordinarytransversewatertight bulkheads,inadditiontowithstandingwaterpressureinanemergencysituation,i.e.,flooding,thebulkheadstructuresconstitutethemainstructuralstrengthelementsinthestructuraldesignoftheintactvessel.Ensuringthatacceptablestrengthismaintainedforthesestructuresisthereforeofmajorimportance.

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6.2.12 Thestructuremaysometimesappeartobeingoodconditionwhenitisinfactexcessivelycorroded.Inviewofthis,appropriateaccessarrangementsshouldbeprovidedtoenableapropercloseupinspectionandthicknessassessment.*6.2.13 Itis imperativeto realisethatin theeventof one hold flooding,the transversewatertight bulkheadspreventprogressivefloodingandthereforealsopreventtheshipfromsinking.

What to look for

6.2.14 Thefollowingareexamplesofthemorecommondamage/defectsthatmayoccur:.1 Fractures attheboundariesofcorrugationsandbulkheadstools,particularlyinwayofshelf

plates,shedderplates,deck,innerbottom,etc.

.2 Buckling oftheplating/corrugations,leadingtothefailureandcollapseofthebulkheadunderwaterpressureinanemergencysituation.

.3 Excessive wastage/corrosion, inparticularat themidheightandbottomofbulkheads,whichmaylookindeceptivelygoodcondition.Thisiscreatedbythecorrosiveeffectofcargoandenvironment,inparticularwhenthestructureisnotcoated.Inthisrespectspecialattentionshouldbegiventothefollowingareas:

.3.1 bulkheadplatingadjacenttotheshellplating;

.3.2 bulkhead trunks which form partof the venting, filling and discharging arrangements

betweenthetopsidetanksandthehoppertanks;

.3.3 bulkheadplatingandweldconnectionstothelower/upperstoolshelfplates;

.3.4 weldconnectionsofstoolplatingtothelower/upperstoolshelfplatesandinnerbottom;

.3.5 inwayofweldconnectionstotopsidetanksandhoppertanks;

.3.6 anyareaswherecoatingshavebrokendownandthereisevidenceofcorrosionorwastage.Itisrecommendedthatrandomthicknessdeterminationbetakentoestablishthelevelofdiminution;and

.3.7 otherstructures,e.g.,diaphragmsinsidethestools,particularlyattheirupperandlowerweldconnections.

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Figure13 Typical fracturing at the connection of transverse bulkhead structure

*Refertosection5.3ofannexAtoresolutionA.744(18),Guidelinesontheenhancedprogrammeofinspectionsduringsurveysofbulkcarriersandoiltankers,asamended,andtotheGuidelinesonthemeansofaccesstostructuresforinspectionand

maintenanceofoiltankersandbulkcarriers(MSC/Circ.686).

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Damage caused by cargoes

6.2.15 Incargoholds,tanktopplatingandsideshellstructuresareapttobedamagedbycargohandlingoperations.6.2.16 Atloadingand unloadingports for coalorironore, largegrabbuckets, highcapacitycargoloaders,bulldozersandpneumatichammersmaybeemployedforcargo~handlingoperations.6.2.17 Largegrabbucketsmaycauseconsiderabledamagetotanktopplatingwhenbeingdroppedtograbcargo.Useofbulldozersandpneumatichammersmayalsobeharmfultocargoholdstructures

andmayresultindamagetotanktops,bilgehoppers,holdframesandendbrackets.6.2.18 Lumbercargoesmayalsocausedamagetothecargoholdstructuresofsmallerbulkersthatareemployedinthecarriageoflightbulkcargoesandlumbers.

Cracking

6.2.19.1 Combination cargo/ballast hold

Inbulkcarriershavingcombinationcargo/ballastholds,cracksmayoftenbefoundatorneartheconnectionofthestoolofthetransversebulkheadandthetanktop.

Figure14 Cracking at the connection of bulkhead stool and tanktop

Allcapesizeandpanamaxbulkcarriersandsomehandybulkershavecombinationcargo/ballasthold(s)tokeepthenecessarydraught.Thebulkheadboundariesofthespacesaredesignedtocomplywith therequirements fordeeptank bulkheads. Intheseholdscracksmayoftenbefoundat theconnectionbetweenthetransversebulkheadandthetanktop.Thesecrackscanbedetectedbyvisualinspectionorbynotingleakagefromthedoublebottomtanks.

6.2.19.2 Others

Sidestringersand/orsideshellsinwayofNo.1cargoholdalongthecollisionbulkheadareoftenfound

cracked.Thiskindofdamageisconsideredtobecausedbyinsufficientcontinuitybetweenforepeakconstructionandcargoholdstructure.

Onlargebulkcarrierssuchascapesizeandpanamaxbulkers,bilgehopperplatingaroundtheknucklelinemaybecrackedalongthebilgehoppertransversewebs.Thisisconsideredtobecausedbyinsufficientlocalreinforcement.

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9 7 5 4 2

Figure15 Cracking around the collision bulkhead Figure16 Cracking in the bilge hopper

6.3 Topsidetanks6.3.1 Corrosionandwastageofsteel,especiallyintheupperpartofthetopsidetanks,shouldbecarefullywatched.

6.3.2 Thoughthewaterballasttanksofnewerbulkcarriersarewellprotectedagainstcorrosion,theupperportionissusceptibletocorrosionbecausetheprotectivecoatingwilleasilydeterioratedueto

heatfromtheupperdeckandthecyclicwet/dryeffectofseawater.

6.4 Bilgehopper/double-bottomtanks6.4.1 Whencarryingoutinspectionsofthesetanks,particularattentionshouldbepaidtoanycracking,deformationordeteriorationofcoating.

Cracking in bilge hopper and double-bottom tanks

6.4.2 Cracksmaybefoundat theintersectionsoflongitudinalsandtransversemembersandatotherlocationsasfollows:

.1 Intersections of longitudinals and solid floorsCracksmaybefoundintheside,bottomand/ortanktoplongitudinalsatintersectionswith

solidfloorsorbilgehoppertransverses.Cracksalsomaybefoundinthefloorsortransversesoccurringatthecornersoftheslotscutforlongitudinals.

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Figure17 Cracking in tanktop/bottom longitudinals

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.2 Cracking of longitudinals at areas of structural discontinuity

Longitudinalsmaybecrackedattheendsofadditional (partial)sidegirdersprovidedin thedoublebottombelowcargoholdbulkheadsoratthesidewallsofbilgewellsforcargoholds,duetoadditionalstressconcentrationcausedbythestructuraldiscontinuityatthoseconnections.

(a) (b)

Figure18 (a) Cracking at the end connection with side walls of bilge well; (b) Cracking at the end of anadditional girder.

.3 Bilge hopper transverseCracksmaybeobservedintransversewebsinbilgehoppersinitiatingfromtheslotopeningsforlongitudinalsandattheknuckledcornersofthelowerendsofthehoppers.

Figure19 Check points in bilge hopper transverse

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Corrosion

6.4.3 Corrosionmustbecarefullywatchedintheinspectionofwaterballasttanks,particularlyinolder bulkcarriersover10yearsofage.Ingeneral,theconditionofthesteelandprotectivecoatingswillbeinsatisfactoryconditionmuchlongerinthedoublebottomsthaninthetopsidecompartments.However,evendoublebottomtankswilldeteriorateintimeduetothecontinualballastingoftheship.

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.1 Corrosion accelerated by heat

Since thelate‘70s,problemswithheavycorrosionindoublebottomwaterballasttanksadjacenttofueloiltankshaveappeared.Insomecases,thecorrosionwasworseinareasclosertothefueloiltankboundaries.Inthoseships,fueloiltankswereinstalled.

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Figure20 Areas where heavy corrosion due to heat effect may be found (hatched areas)

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Figure21 Progress of corrosion in water ballast tanks adjacent to fuel oil tanks (FOT)

Thefueloilheatingsystemwasadoptedfollowingchangestothepropertiesoffueloil,mainlyanincrease inviscosity.For economicreasons,shipoperatorsbegantouselowgradebunkeroilwhichneedsheatinginordertodecreasetheviscosity.Atthebeginningofthistrend,the

temperaturerequiredinthefueloiltankswasnothighenoughtoacceleratethecorrosionofthesteelintheadjacentspaces.However,inrecentyears,thegradeofbunkeroilbeingusedrequiresthetemperatureinthetanktobe80°Cormore.Suchatemperaturecanacceleratecorrosionofthesteelinthetanks,particularlyinthevicinityoftheboundariesofthefueloiltanks.

.2 Areas under suction bellmouthsBottomplatesareoftenerodedunderthesuctionbellmouthsintanks.Ondrydockingofanoldership,thebellmouthsshouldbedismantledforexaminationoftheconditionoftheshellplatesbelowthebellmouths.

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6.5 Othernotices

Bottom ends of sounding pipes

6.5.1 Asoundingpipehasapadplateatitsbottomendforprotectionofthetankbottomagainstthestrikeof thesoundingscale’slead.Duringinspectionstheextentofdiminutionoftheprotectionplateshouldbeexamined.

Connection trunk between topside and bilge hopper spaces

6.5.2 Connectiontrunksprovidedbetweentopsideandbilgehopperspacesaretobecarefullywatchedforsignsofcorrosionandwasteofthesteelworksinside.

6.5.3 Onsomebulkcarriers,bilgehoppertanksandtopsidetanksformoneintegraltankconnectedwithtrunkspaces.Theinsidesurfaceofaconnectiontrunkisliabletocorrosionandshouldbeexaminedcarefully.

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Figure22 Connection trunk entrance in topside tank

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