Onderwerp: Bezoek-historie

1117 Guidance For Checking The Structure Of Bulk Carriers
Geldigheid:24-06-2004 t/m Status: Geldig vandaag

Dit onderwerp bevat de volgende rubrieken.

 

 

Ref. T1/2.01                                                                                                               MSC/Circ.1117

24 June 2004

 

1          The  Maritime  Safety  Committee,  at  its  seventy-eighth  session  (12  to  21 May  2004), followingitsdecisionthatportStatesandthevariousportStatecontrolregimesworldwideshouldbe stronglyrecommendedtodevelopspecializedtraining,pinpointingthevulnerableareaswithinthe structure,inparticularofolderships,andhavingconsideredtherecommendationmadebythe Sub-CommitteeonFlagStateImplementationatitstwelfthsession,approvedtheGuidancefor checking the structure of bulk carriers, as set out in the annex.

 

2          MemberGovernmentsareinvitedtobringtheannexedGuidancetotheattentionofallparties concerned.

 

 

 

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Annex

1          ThisguidanceistoassistportStatecontrolofficers(PSCOs)incheckingthestructureaswell as the operational aspects of bulk carriers during port State control inspections.

 

2          In addition to this guidance, PSCOs should refer to the following documents:

 

.1         SOLAS chapter XII - Additional safety measures for bulk carriers;

 

.2         resolutionA.862(20)-CodeofPracticefortheSafeLoadingandUnloadingofBulk

Carriers;

 

.3         resolutionA.866(20)-Guidancetoships'crewsandterminalpersonnelforbulk carrier inspections; and

 

.4         resolution  A.744(18)  as  amended  - Guidelines  on  the  enhanced  programme  of inspections during surveys of bulk carriers and oil tankers.

 

3          PSCOs are further invited to consult the following IACS publications, if available:

 

.1         Bulk Carriers: Guidelines for Surveys, Assessment and Repair of Hull Structure;

 

.2         BulkCarriers:GuidanceandInformationonBulkCargoLoadingandDischargingto

Reduce the Likelihood of Over-Stressing the Hull Structure; and

 

.3         Bulk Carriers ñ Handle With Care.

 

Documentation

 

4          Whilecheckingtheship'sdocumentation,PSCOsshouldpayparticularattentiontothe loadingplan,cargodistributionandloading/unloadingsequencestoascertainthattheshipisloaded in accordance with the approved loading manual.

 

5          PSCOsshouldpayparticularattentiontothetanktoplimitation,thebendingmomentsand shearingforcesaswellasthecargodistribution.  Pastexperienceshowsthatshipsoftenloadin patternsnotapprovedinthestabilitymanual.  For example, on board a nine-hold bulk carrier, the approvedstabilitymanualoftenhasanannotationstatingthatholds2,4,6and8maybeempty. Thisimpliesthatallevennumberholdsmustbeemptyatthesametime.   Inmanycases,ship officersbelievethatsuchanannotationallowsforanycombinationoftheseholdstobeempty, which is not the case.

 

6          PSCOsshouldrememberthatloadingpatternsnotincludedintheapprovedstabilitymanual shouldnotbeacceptedsincethismightcreateexcessivelocalstresstotheship'sstructureregardless of the fact that the bending moments and shearing forces are within the permissible values.

 

 

7          WhenitisestablishedduringaPSCinspectionthatashiploadingpatternisnotperthe approvedstabilitymanuals,thePSCOshouldrequestconfirmationinthefirstinstancebytheship's officers,bytheflagStateadministration,ortherecognizedorganizationworkingonbehalfofthe flagState,thattheproposedloadingplan/distributionisacceptable.  Intheeventthatashipisfound non-compliantwiththeapprovedstabilitymanualsduringunloadingoperations,thePSCOshould inform  the  master  and  chief  officer  that  future  loading  should  be  within  the  limitation  of  the approved stability manual.

 

8          Initially,acheckofthesurveyreportfilemayidentifypossiblesuspectareasrequiring inspection.  TheprovisionscontainedinresolutionA.744(18)asamended,requireaspecificsurvey programme  which  includes  access  arrangements  and,  when  necessary,  the  requirements  for  a close-upsurveyandthicknessmeasurements.  Asurvey report file is required to be held on board consisting of:

 

.1         reports of structural surveys;

 

.2         condition evaluation reports;

 

.3         thickness measurement reports; and

 

.4         survey planning document (or equivalent) containing the following information:

 

.4.1      main particulars;

 

.4.2      plan of tanks and holds;

 

.4.3      list  of  tanks  and  holds  and  usage,  corrosion  protection  and  condition  of coating;

 

.4.4      corrosion risk in tanks; and

 

.4.5      design risk of structures.

 

Inspection

 

9          Ideally,inspectionsshouldbecarriedoutbyateamofatleasttwoPSCOsandinclude,at least,onepersonwithanin-depthknowledgeofshipstructures.Inaloadingporttheyshouldbe readytoboardtheshiponarrival.  Inadischargeport,informationonthelikelydischargesequences shouldbeobtained,wherepossible,sothattheinspectioncanbecarriedoutwhenholdsbecome available.

 

10        Accesstotheupperpartsofholdsisproblematic.Laddersmayhelpandexperiencehas shown  that  using  binoculars  along  with  high-powered  torches  can  assist  in  making  an  initial assessmentoftheconditionofinaccessibleparts.Iftheconditionofotherpartsoftheholdandthe hull  structure  in  general  give  rise  to  concern,theflagState/recognizedorganizationshouldbe consulted to consider the need for a more detailed survey.

 

 

11        Theimpressionofhullmaintenanceandgeneralstateondeck,theconditionofitemssuchas ladders,  hatches,  air  pipes,  guardrails,  visible  evidence  of  previously  effected  repairs,  and  the conditionofdeckmachineryshouldinfluencethePSCO'sdecisiononwhethertomakethefullest possible examination of the hull.

 

12        Special attention should be given to areas of high stress and bending moments, such as:

 

.1         immediately forward of the engine-roombulkhead;

 

.2         over the midships half-length; and

 

.3         no.1 hold side shell framing and top and bottomconnections (panting region).

 

13        Particularattentionshouldbegiventoareaswherefracturing,cracks,distortionorexcessive wastagecanoccur.  Theseareasareillustratedinthediagramsinappendices1and2*.Theweather tightintegrityofhatchesandclosuresisparticularlyimportantonorecarrierswithminimalreserve buoyancy.

 

14        Common defects are:

 

.1         cracking at hatch corners;

 

.2         plate panel buckling of cross deck strips and stiffening structure;

 

.3         cracking of hatch coamings;

 

.4         cracking at intersection of the inner bottomplating and the hopper plating;

 

.5         grab and bulldozer damage to the side shell frames lower brackets;

 

.6         grab damage to the inner bottomplating, hopper and lower stool plating;

 

.7         cracking at side shell frame bracket toes;

 

.8         both general and localized corrosion of side shell frames and brackets;

 

.9         cracking at fore and aft extremities oftopside tank structures;

 

.10       corrosion within topside tanks; and

 

.11       general corrosion and cracking of transverse bulkheads.

 

 

 

 

15        If  tanks  or  holds  are  to  be  inspected,  the  PSCO  should  ensure  it  is  safe  to  enter.   The requirementsoftheCodeofSafePracticeforSolidBulkCargoes,AppendixF,apply.  Additional safeguards  could  include  carrying  personal  devices  capable  of  determining  the  safety  of  tank atmospheres or employing the services of a chemist to check the atmosphere.

 

16        Permanentseawaterballasttanksrepresentoneofthemostlikelyproblemareasand,if inspected, the following aspects should be considered:

 

.1         thepaintconditionincoatedballasttanksandconditionofanodes.  Inballasttanks, ratesofcorrosionintheorderof1mmperyearmaybeencountered,dependingon whethertheyarecoatedorprotectedbyanodes.  Insomeships,onlytheullagespace

iscoatedwiththeremainderprotectedbyanodes.  Duringemptyperiods,thiscan result in corrosion on uncoated structures, which remain wet;

 

.2         intanksusedforballastthatmaybesubjecttovariabledepthsofseawater,for exampleforepeaktanks,itisoftenthecasethatthereislittlewastagetopandbottom, butsignificantwastageovercentralregions.Attentionshouldbepaidtolongitudinal stiffeners and brackets at the collision bulkhead to shell junction;

 

.3         longitudinalshellstiffenersindedicatedballasttanks,particularlyinareasadjacent to bulkheads and web frames; and

 

.4         underdecklongitudinalsinballasttanks.Wastageisusuallythemostseverecloseto thedeckhead.  Thismayresultinthefilletwelds,attachinglongitudinalstothedeck, being  wasted  thus  leading  to  detachment  of  the  longitudinals  and  consequent buckling of deck plates.

 

17        Whereafracture,whichhasnotbeencausedbycontactdamage,isfoundinthemainhull structureononesideofaship,thecorrespondingstructureontheoppositesideshouldbeexamined toseeifasimilarfailurehasoccurred.  Fracturesofthisnatureareofconcern,especiallywhere corrosion is associated with the failure and may have been a contributing factor.

 

18        Ifrelevant,thePSCOmaycheckthatthenecessarycalculationshavebeenmadetoensure bendingandshearstressesaremaintainedwithinmaximumlimitsbothduringloading/dischargeand theensuingvoyage.Thisisespeciallyimportantwherehighdensitycargoesarecarriedorwherethe loading/ballastingarrangementisofadifferentconfigurationtothatdescribedintheship'sloading manual.

 

19        Inreachinganydecisionregardingadetention,thePSCOshouldconsidertheseaworthiness andnottheageoftheship,makingallowanceforfairwearandtearovertheminimumacceptable scantlings.  Wherethereisdoubt,theclassification society should advise the accepted diminution ratesofstructuralmembers.  Damagenotaffectingseaworthinessshouldnotconstitutegroundsfor judgingthatashipshouldbedetained,norshoulddamagetemporarilybuteffectivelyrepairedfora voyagetoaportforpermanentrepairs.  However,inhisassessmentoftheeffectofdamages,the PSCO  should  have  regard  to  the  location  of  crew  accommodation  and  whether  the  damage substantially affects its habitability.

 

 

 

 

 

20        Anyproposalsfrom theflagStateorclassificationsocietyshouldbeconsideredcarefully.

Specificationofrepairsistheresponsibilityoftheclassificationsocietysurveyorandneedonlybe agreedtobythePSCO.  Intheeventthattheproposalsareacceptable,careshouldbetakentoensure thattheflagStateandclassificationsocietyoverseetherepairsandcleartheshipbeforearequestto

lift the detention is made.

 

21        AnyproposalbytheflagStatetoallowtheshiptomakeasinglevoyagetoarepairyard should   be   in   accordance   with   chapter   4.7   of   resolution   A.787(19)   as   amended   by resolution A.882(21) on Procedures for port State control.

 

 

 

 

 _________________

 

*                       DiagramsintheappendicesarereproducedwiththekindpermissionofIACS,Lloyd'sRegisterandNipponKaijiKyokai.

 

Appendix 1 What To Look For In Holds

 



 



Appendix 2 What To Look For On Deck


 
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