heger dry dock, inc...heger dry dock, inc. bae systems ship repair holliston, ma san francisco, ca...
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HEGER DRY DOCK, INC Structural/Marine Engineers
531 Concord Street Holliston, MA 01746
Tel 508-429-1800 Fax 508-429-1811
Letter 16-87L Page 1
16‐87L December7,2016Attention: EddieGoldman,SeniorDockmaster([email protected]) JustinGleaton,Dockmaster([email protected])Re: RequestforHEGERCertificationofDryDockNo.2locatedinBAESanFrancisco,CAReferences:
(1) HEGERStructuralandMechanical/ElectricalControlInspectionReportforFDDNo.2,Aug2016(2) INTERNATIONALINSPECTIONUltrasonicGaugingSurveyReportforFDDNo.2,Jan2016(3) DRYDOCK#2FacilityCertificationReport,December1987(4) BRUCES.ROSENBLATT&ASSOCIATESDDNo.2FiniteElementAnalysis,August2016
Enclosures:
(1) HEGERDrawingPackage(2) TRITONMooringLimitations
Gentlemen: HEGERDRYDOCK,INC.hasbeenaskedtocommerciallycertifyDryDockNo.2atBAESYSTEMS’sSanFranciscoShipyardinaccordancewithUSGCSFLCSTDSPEC8634.ThecertificationofthefloatingdrydockwillbebasedonthematerialandoperationalinspectionperformedbyWaleedSayedandMichaelNaylor,bothengineersatHegerDryDock,onAugust8ththroughthe12th,2016.SeeReference1formoreinformationonsurveyresults.InordertoissueacommercialcapacitycertificationforDryDockNo.2,HegerDryDockconductedadesignreviewtoestablishoperationallimitationsbasedonthedock’scurrentcondition.TheobjectiveofthisletteristopresenttheresultsofHEGER’sdesignreview.Thereviewoutlinesthedrydock’slimitationsandnotablestructuraldeficienciesofthedock’scurrentcondition.Thedesignreviewincludes:
Transversebendinganalysis/FEAreview Longitudinalbendinganalysis Localstrengthcalculationsbasedonhydrostaticheadpressure Intactstabilitycalculations ReviewofBAE’smooringcalculationsandlimitations
HEGERhascompiledahistoryofthedock’sdrawingsforthepurposeofevaluatingandperformingthedesignreview.RefertothefollowingdrawingsofEnclosure1formoreinformation: A‐001 GENERALARRANGEMENT
S‐301 SECTION‐TYPICALTRANSVERSE S‐302 SECTION‐TRANSVERSENWTBULKHEADS‐303 SECTION‐TRANSVERSEWT/NWTBULKHEAD
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 2
DescriptionofDockDryDockNo.2isaonepiecetypesteelfloatingdrydock.ThedrydockwasconstructedbytheBethlehemSteelCorporationattheirSanFranciscoYardin1970.ThedesignofthedrydockwasdonebyEarlandWright,ConsultingEngineersofSanFrancisco.Thedock’spontoonisdividedintoforty(40)ballasttanks;twenty(20)porttanksandtwenty(20)starboardtanks.Eachballasttankis40’‐0”longx84’‐0”wide.Eachballasttankisfloodedviaa20”diameterbutterflyvalveoperatedbyanelectricactuatorlocatedonthesafetydeck.Eachballasttankisdewateredbyasingle‐stagemixedflowverticalshaftpumpwithanapproximatecapacityof6,000GPM.Thepumpsandvalvesareoperatedremotelybypushbuttonsinthecontrolhouse.Thereisan18’‐0”widebuoyancychamberlocatedalongthedock’scenterline.Thebuoyancychamberisdividedintofive(5)compartmentsofvaryinglengthslongitudinally.
PRINCIPALCHARACTERISTICSOFTHEDOCK
AgeofDock.....................................................................46yearsLengthOverall...............................................................900’‐0”LengthofPontoon.......................................................800’‐0”BreadthOverall.............................................................186’‐0”BreadthbetweenWingwalls...................................150’‐0”HeightofWingwallAboveKeel..............................66’‐0”PontoonDepth..............................................................20’‐0”DesignCapacity(18”Freeboard)..........................59,600LTDesignKeelLoadLineRating.................................84LT/ft
RefertoEnclosure1foraGeneralArrangementdrawingofthedrydock.BuoyantCapacityHEGERhasreviewedthedrydock’sbuoyantliftcalculationsshownintheFCR(seeReference3).Thedockhadanoriginaldesignbuoyantliftcapacityof59,600LT.Thedock’sFacilityCertificationReportassumedthefollowingdocklightweightproperties:
DockLightweight(NoBallast)................................15,500LTVerticalCenterofGravity.........................................25.00ftabovebaseline
FreeboardmeasurementstakenonJanuary3,1986showedthedockwascapableofachievingalightdraftof4.48feet.Thisrepresentsadocklightweightof17,400LT(dockweight&residualballastof1,900LT).Thedockhasanoperatingfreeboardof18inches(equivalenttoadockdraftof18.50feet).Atthisoperatingfreeboardthedockhasadisplacementof77,170LT.Basedonthe1986freeboardmeasurements,thedockwouldhaveabout59,670LTofbuoyantcapacityavailabletoliftavesselandtrimmingwater.DuringHEGER’sinspectionofthedock(August2016),asignificantamountofmuddepositwasobservedintheballasttanks.Someareashadmuddepositsofapproximatelytwofeet.Therehasalsobeenextensivestructuralmodificationtothedocksuchastheadditionof1/2“doublerplatestothepontoondeck,newwingwallcranes,andsix(6)stabilitysponsons.Theconcernisthatthemuddepositsandstructuralmodificationsovertheyearshaveincreasedthedock’slightweightandthe1986buoyantcapacityisnolongerachievableatthe18”operatingfreeboard.
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 3
MorerecentFEAreport(seeReference4)indicatesthedock’scurrentlightweighthasincreasedby3,750LTto:
DockLightweight(NoBallast)...............................................19,250LTVerticalCenterofGravity.........................................................26.22ftabovebaseline
Inordertogainadditionalliftcapacitythathasbeencompensatedbytheabove‐mentionedaddedweight,HEGERsuggestscertificationofthedock’sliftcapacityatalower12”ofpontoondeckfreeboard.Thereducedoperatingfreeboardwouldgain2,159LTofliftcapacity.Basedonthemostcurrentdocklightweightinformation,thedockwouldhaveabuoyantcapacityof58,000LTat12”ofoperatingfreeboardand55,800LTat18”ofoperatingfreeboard.Ifadditionalliftcapacityisdesired,ballasttankswouldhavetobemucked.Itisimportanttonotethatalthough12”ofoperatingfreeboardispermittedbyABSrules,MIL‐STDrulesmandatean18”operatingfreeboardforthiscapacitydock.HEGERwillneedtofieldverifyDryDockNo.2’scurrentdockweightandliftcapacitywithfieldmeasurementsatthenextsurveypriortoissuingacommercialcertification.IntactStabilityoftheDryDockDryDockNo.2wasrenovatedin2008byaddingsix(6)40’x12’sponsonsinordertoincreaseitstransverseintactstabilityfordockingphases3and4.HEGERhasdevelopedanallowableKGversusvesselweightcurveforthefloatingdrydockforaminimumGMof3.28feetasrequiredbyABS.ThestabilitycurveisshownFigure1below.Plottedpointsthatfallonorbelowthislineareacceptable,pointsaboveareunacceptable.
FIGURE1–IntactStabilityCurve
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 4
MaximumSubmergenceDraftsDryDockNo.2’scurrentsubmergenceberthlimitsthedock’smaximumpossiblesubmergenceto59’‐6”,witha6‐fttide(accordingtoBAE).AllowableHeadPressuresBasedonthemaximumachievabledraftandthecorrespondinginternalballasttankwaterlevels,HEGERhascalculatedthemaximumallowableheadpressuretobeabout28‐ft,duringadockingevolutionofacapacityvessel,providedanengineeredpumpingplanisfollowed.Anemptydockorunloadedtankexperiencesahydrostaticheadpressureofabout10‐ft,duringasubmergenceevolutionprovidedanengineeredpumpingplanisfollowed.ExternalShellThedesignofthedock’sexternalshellthicknessrequirementistypicallygovernedbythestrengthrequiredtoresisthydrostaticheadpressuresexperiencedduringadockingevolution.HEGERhascalculatedtheallowablehydrostaticheadpressuretheexternalshellcansafelyresistforagivencorrodedplatethicknessusingthedock’sdesignedstiffenerspacing(typically25”).Theoriginaldesignthicknessofthewingwallsideshellplatingwas7/16”or0.44inches.TheallowableheadpressureisbasedonbasedonABSRulesforBuilding&ClassingSteelFloatingDryDocks2009.TheresultsareasfollowsandareshowninFigure2:
PlateThickness Corrosion AllowableHeadPressure
0.35inches 20% 28.2feet 0.30inches 31% 18.4feet 0.25inches 43% 10.7feet
FIGURE2–AllowableHeadPressurevs.PlateThicknessCurve
10.0
15.0
20.0
25.0
30.0
35.0
40.0
0.24 0.26 0.28 0.30 0.32 0.34 0.36 0.38 0.40
Allo
wab
le Head
Pressure (ft)
Plate Thickness (in)
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 5
TocreatethechartinFigure2,theassumptionisthattheanglestiffenersweldedtotheshellplatehave15%corrosionorless.HEGERhasreviewedthedock’smostrecentUTsurveyconductedbyInternationalInspectioninJanuary2016inordertoevaluatethedock’scurrentcondition,after45yearsofservice,withtheintentofdetermininganallowableheadpressureonatankbytankbasis.Allowableheadpressureisbasedonremainingmaterialthicknessoftheshellplate.TheUTsurveyresultsofthedock’sexternalshellplatingindicateareasofsignificantmetalthicknessloss.AreasofextensivecorrosionwereconfirmedbyHEGER’sAugust2016visualinspectionwithnumerousobservedholesintheplating.Themostnotableareasofcorrosionare:
OutboardShellPlating,specificallyinwayofthesplashzone(2‐ftbelowthepontoondeckto10‐
ftabovethepontoondeck)
Connectionoftheinboardwingwallsandthepontoondeck
Therehavebeenongoingrepaireffortstothedock’soriginalexternalplatingtofixareasofextensivecorrosionandholed‐throughplating.Somelocationshavebeenrepairedbyinstallingdoublerplatesoverlocalizedholes.Otherareasoftheexternalshellhavebeenrepairedbycroppingandreplacing40‐ftx10‐ftstiffenedplatepanels.Thethicknessofthenewplatepanelshasbeenincreasedto1/2”fromtheoriginal7/16”.ThemajorityoftheexternalshellrepairshavebeenmadetotheEastandWestoutboardshellswithabout20%ofthedock’soriginalplatepanelsbeingreplaced.NOTE:Theamountofvesselloadplacedoveratankgroupwilldirectlycorrelatetotheamountofheadpressurethattankgroupexperiencesinadockingevolution.Therefore,theamountofvesselloadthatcanbepositionedoveraspecifictankgroupwillbelimitedbytheminimummeasuredUltrasonicThickness(UT)measurementsurveyedinthattankgroup.
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 6
PontoonDeck&TransverseBendingStrengthThedock’soriginalpontoondeckisseverelycorrodedasreflectedinthemostrecentultrasonicthickness(UT)measurementssurveyedbyInternationalInspectioninJanuary2016(seeReference2).UTmeasurementsweretakeninternallyandmeasuredthethicknessoftheoriginaldeckplateonly.Doublerplateshavebeeninstalledonthetopsideofthedrydock’soriginalpontoondeckplateoverabout65%ofthesurfacewithaconcentrationtowardsthedock’scenterline.Thedoublerplatesare1/2”inthicknessandareconnectedtothedock’soriginalpontoondeckplatevia2”x6”slotweldslocatedalongtransverseandlongitudinalstructure.Theseslotsweldsareconsideredessentialastheyprovidethedoublerplateswithrequiredbucklingcapacity.Thehalf‐inchdoublerplateswereinstalledtofortifytheoriginaldeckplateasanalternativetoremovingandreplacingthecorrodedplatingandstiffeners.HEGERhasanalyzedthedrydock’spontoondeckforbothlocalhydrostaticpressureandtransversestrengthrequirementswhenliftingakeellineloadingatthedock’scenterline.Hydrostaticpressurethicknessrequirementsaresimilartothoseoutlinedintheexternalshellsectionofthisletterasthestiffenerspacingissimilar.Anallowableheadpressureratingof28feetisrecommendedataminimum.Thetransversebendingcalculationswereanalyzedusingaloadingof68LT/fttoverifythelocalstructuralcapacitysuggestedbythedock’smostrecentFEAreport(seeReference4).IntheFEAreport,thedock’stransversecapacityisgovernedbyaconservativeremainingthicknessassumptionofthepontoonbottomplating.Thelatest2016UTmeasurementsshow20%corrosioninthemostsuspectplaces;theFEAanalysismodeledportionsofthebottomat50%toallowforfuturecorrosion.Belowisthepontoondeckthicknessrequirementstosupport68LT/FTbasedonlocationoffofdockcenterlinefromtheanalysis.
*Controlledbyhydrostaticheadpressureof28feet. Areviewofallowablepontoondeckvehiculartrafficlimitationswasnotconductedaspartofthisdesignreviewasitdoesnotinfluencethesafetyofthevesselindrydock.
LocationoffDockCenterline(ft)
PlateThicknessRequired(in)
0‐1.5 0.431.5‐3.5 0.383.5‐9 0.369‐27 0.4027‐32 0.35*32‐44 0.35*44‐50 0.35*50‐54 0.35*54‐67 0.35*
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 7
MooringInordertomeetHEGERcertificationrequirements,adrydockneedstobeadequatelymooredtothepier.InMayof2016,TroyGillum,PEofTritonEngineering,Inc.conductedanengineeringanalysisofDryDockNo.2’smooringtodeterminetheoperationalwindspeedrestrictions,basedonafewdifferentvesseltypesondrydockandthedirectionofthewind.SeeEnclosure2formoreinformation.ToobtainandmaintainHEGERcertification,BAEwillberequiredtoadheretothesewindspeedrestrictionstomaintainasafeoperationofthedrydock.Thismayprecludedockinglargervesselsuntilthemooringisstrengthened.Inaddition,ifavessel’ssailarealimitstheallowablewindspeedfromanydirectiontobelow65knots,basedonmooringstrength,itshouldnotbedocked.Ifwindeventsareforecastedthatmayexceedtheallowedwindspeedforaparticularvessel’ssailarea,proceduresneedtobeinplacetoundockthatvesselbeforethepredictedeventoccurs.The65knotlimitationisbasedona10yearmeanrateofoccurrencefortheSanFranciscolocationaccordingtotheAppliedTechnologyCouncil.HEGERrecommendsthatBAEbeginexploringmethodsofstrengtheningtheirmooringdolphinsinordertoincreasethemaximumallowablewindspeedstomeetcurrentASCEcriterion.LongitudinalStrengthHEGERhasreviewedthedrydock’slongitudinalbendingcalculationsshownintheFCR(seeReference3).Thedock’soriginaldeflectionlimitwas+/‐3inches.HEGERhasperformedcorrespondinglongitudinalstrengthcalculationtoverifythedockhasadequatelongitudinalstrength.BasedonUTreports,wehaveassumedalldockstructureiscorroded15%oforiginalthicknesswiththeexceptionofthepontoondeckwhichwehaveassumedtobe50%corroded.HEGERhasconcludedthedockhasadequatelongitudinalstrengthforthecurrent+/‐3inchesdeflectionlimit.Thedock’slongitudinaldeflectionshouldbemonitoredduringalldockoperationstoensurethelimitationsarenotexceeded.Anengineeredpumpingplanshouldbedevelopedfordockingandundockingevolutionstominimizelongitudinalstressanddeflection.ConclusionandRequiredRepairsforHEGERCertificationHEGER’sprimaryconcernwiththedock’scurrentstructuralconditionistheseverelycorrodedshellplating,withnumberofholed‐throughareas.Theholes,locatedthroughoutthedock,impedethewatertightintegrityofnumerousballasttanksandraisethefollowingconcerns:
1. Thedockcannotholddraftwithoutoperatingpumpstooffsettheleakingofballasttanks.ThiswasconfirmedandobservedinHEGER’ssubmergencetestconductedinthe2016controlinspection.
2. Theholed‐throughplatingcreateslocalhydrostaticstrengthdeficiencieswhichputcorrodedareasofthedockatriskoffailure.Duetolackofmaterialstrength,thereisthepotentialfortheseholestoenlargesignificantlyduringadockingevolution,toapointwheretheamountofexternalleakagecannotbeoffsetbythedock’spumps.Itshouldalsobenotedthatthedockdoesnothaveemergencycross‐connectvaluesintheevent
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 8
anindividualtank’spumpislost,thuslosingtheabilitytooffsetexternalleakage.InorderforHEGERtocertifythisdock,BAEwillberequiredtorepairthestructurallydeficientareasoftheexternalshellandmakerepairstoholesintheexternalshelltore‐establishthedock’swatertightintegrityandensuresafedockoperations.BasedonHEGER’sknowledgeofthedock’sdesignreview,visualconditionsurvey,andmostrecentUTsurvey,areasofthedock’sstructuraldeficiencieshavebeenmappedoutontheinboardandoutboardwingshellsandthepontoondeckinthedrawingslistedbelow.HEGERhasassignedaPriority1or2totheareasofmoststructuralconcern.Priority1areaswillneedtoberepairedpriortoHEGERcertification.Theseareasareeitherheavilycorrodedasindicatedbythedock’sUTsurveyorcontainholesorotherdeficienciesnotedinthe2016controlinspection.ThesquarefootageofPriority1areasisapproximately21,600sqft.Priority2areaswillneedtoberepairedbeforethesubsequentHEGERre‐certification.Theseareasalsoshowsignsofsignificantcorrosion.Untilthepriority2areasarerepaired,therewillneedtobeoperationalrestrictionsregardingallowedheadpressureintheseareas.ThesquarefootageofPriority2areasisapproximately41,400sqft.Inthedrawingslistedbelow,allareasaregenerallymappedoutonatankbytankbasis.Itisrecommendedtheexternalshellintheseareasbecroppedoutandreplacedwithafabricatedinsertplatetoproperlyrepairthearea.Intheeventofsmallisolatedholes,adoublerplatemaybeinstalledasatemporaryfix.SeethefollowingdrawingsinEnclosure1formoreinformationonUTmeasurementsandPriority1or2repairareas:
A‐002 PONTOONDECK‐1OF2A‐003 PONTOONDECK‐2OF2A‐004 WESTOUTBOARDWINGWALLA‐005 EASTOUTBOARDWINGWALLA‐006 WESTINBOARDWINGWALLA‐007 EASTINBOARDWINGWALLA‐008 PONTOONBOTTOM‐1OF2A‐009 PONTOONBOTTOM‐2OF2
Themajorityofthepontoondeckhasbeencoveredwitha1/2"doublerplate.Thisisnotaviablelongtermsolutionforthedock.HEGERrecommendsamaintenanceplanbedevelopedtoproperlyreplacethecorrodeddeckpanelswithinsertplates.Notethatthedockwasoriginallydesignedwith1/2”highstrengthsteel(yieldpointof50ksi).HEGERrecommendsanypontoondeckreplacementsbe3/4"highstrengthsteel.Notethatthismaycorrespondtoasmallreductionintheliftcapacityofthedockduetoanincreaseindockweight,butwillbuildinadditionalcorrosionallowance.SeeSection4.1ofHegerDryDock’s2016controlinspectionreport(Reference3)foratankbytanklistofnoteddeficiencies.Allrepairsrecommendedtobeaccomplishedassoonaspossibleinsection6ofthereportshouldbeconsideredPriority1andaddressedpriortoHEGERcertification.
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Heger Dry Dock, Inc. BAE Systems Ship Repair Holliston, MA San Francisco, CA
Letter 16-87L Page 9
OncePriority1repairshavebeenaccomplished,HEGERwillfieldverifytheconditionofthedockandtakelightdockfreeboardsinordertocertifythedockinaccordancewithUSGCSFLCSTDSPEC8634iftheconditionsowarrants.Basedontheresultsofthisdesignreviewthedockisexpectedtohavethefollowingoperationallimitations:
LiftCapacity(18”Freeboard).................................................55,800LTLiftCapacity(12”Freeboard).................................................58,000LTMaxKeelLineLoad.....................................................................68LT/ft ExternalWaterDifferential.....................................................varies,max28feet InternalWaterDifferential......................................................20ftMaxSubmergenceDraft(on6’tide)....................................59’‐6”LongitudinalDeflection.............................................................+/‐3inchesMaxTrim.........................................................................................2ftper100ftMaxList............................................................................................2degreesAllowedWindSpeed..................................................................variesbyship,65knotsmin.required
Duetotheextentoftheexternalshellplatecorrosion,thedockwillhavemaximumexternalheadpressurerestrictiononatankbytankbasis.Themaximumheadpressurethatcanbeappliedtoatankwillbegovernedbytheleastmaterialthicknessmeasurementofthattank.Theexternalheadpressurelimitationswilldirectlyaffecttheamountofvesselloadthatcanbeappliedtothetank.Anemptydockseesapproximately10‐ftofheadpressure.Asmorevesselloadisappliedtothetank,theheadpressureincreases.Eachdockingwillhavetobecarefullylookedattoensurethatatank’soperationalrestrictionisnotexceeded.Duetothevariousoperationalrestrictionspresentedinthisreview,thecertificationissuedbyHEGERwillincludeaclausethatdockingplansandcalculationsforanyvesselexceeding60%ofthedock’sratedliftcapacitywillneedtobereviewedandapprovedbyaHEGERengineerpriortoitsdocking(untilPriority2repairsarecomplete).Pleasecontactmeifyouhaveanyquestionsorcommentsregardingthisletter.
Sincerely,HEGERDRYDOCK,Inc.MichaelNaylorEngineer
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ENCLOSURE1HEGERDrawingPackage
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R
G
H
E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
BAE SYSTEMS SHIP REPAIR
SAN FRANCISCO, CA.
COMMERCIAL CERTIFICATION OF FLOATING DRY DOCK #2
DRYDOCK #2 OPERATIONAL LIMITSGENERAL DRAWING INDEX
G-001
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
PLAN VIEW B1
MIDSHIP SECTION A1
DOCK CHARACTERISTICS
PLAN - TYPICAL BALLAST TANK CONFIGURATION A4
A-001
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
PLAN - PONTOON DECK - UT MEASUREMENTS A1
SYMBOLS KEYA-002
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
PLAN - PONTOON DECK - UT MEASUREMENTS A1
SYMBOLS KEYA-003
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
ELEVATION - WEST OUTBOARD WINGWALL - UT MEASUREMENTS C1
ELEVATION - WEST OUTBOARD WINGWALL - UT MEASUREMENTS A1
SYMBOLS KEY
A-004
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
ELEVATION - EAST OUTBOARD WINGWALL - UT MEASUREMENTS C1
ELEVATION - EAST OUTBOARD WINGWALL - UT MEASUREMENTS A1
A-005
SYMBOLS KEY
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
ELEVATION - WEST INBOARD WINGWALL - UT MEASUREMENTS C1
ELEVATION - WEST INBOARD WINGWALL - UT MEASUREMENTS A1
A-006
SYMBOLS KEY
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E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
ELEVATION - EAST INBOARD WINGWALL - UT MEASUREMENTS C1
ELEVATION - EAST INBOARD WINGWALL - UT MEASUREMENTS A1
A-007
SYMBOLS KEY
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E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
PLAN - PONTOON BOTTOM - UT MEASUREMENTS A1
A-008
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R
G
H
E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
PLAN - PONTOON BOTTOM - UT MEASUREMENTS A1
A-009
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G
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E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
S-301
SECTION - TYP TRANSVERSE A1
SECTION C1
SECTION C3
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G
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E E
DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
S-302
DETAIL C1
SECTION - TRANSVERSE NWT BHD A1
DETAIL - KEEL GIRDER 1'-4 5/8" OFF CENTERLINE D3
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SECTION - TRANSVERSE WT/NWT BHD A1
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DRY DOCK, Inc.
HEGER
DESIGN, INSPECTION AND CERTIFICATION
DRY DOCK ENGINEERS
531 CONCORD STREET
HOLLISTON, MA 01746
(508) 429-1800
BAE
SYST
EMS
S-303
DETAIL C1
DETAIL C4
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ENCLOSURE2TRITONMooringLimitations
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PROJECT:
FOR:
CLIENT:
DRY DOCK NO. 2 WIND STUDY
BAE Systems, Inc. San Francisco Ship Repair
BAE SYSTEMS, INC.
Contact: Justin Gleaton, Dockmaster
6-30-16
May 27, 2016
Troy E. Gillum, P.E.
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