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442703/B
Gatevalveinstallationoverview
Toprotectthetransducer,agatevalvecanbeaddedtothehullunitinstallation.By
meansofamechanicalconstructionitshutsoffthebottomoftheinstallationtrunk
whentheST90isnotused.
Prerequisites
Thistaskmusttakeplaceindrydock.Theshipyardmustprovideallnecessarytools
andmanpower.Relevantcranesandliftingequipmentmustbeavailable.Freeaccess
throughthehullorthedecksmustbeprovided.
Note
Thegatevalveisheavy.Appropriateliftingequipment(liftingtackle,portablecraneor
ship’ scrane)isrequired.Alwaysuseappropriateliftingequipmenttominimizeriskof
personnelinjuryorequipmentdamages.Onlycertiedequipmentmustbeused.
Context
Onlythebasicstepsofthetaskareoffered.Formoreinformation,refertotheother
descriptionsandtasksinthischapter.
Note
Itisveryimportantthatthegatevalvemechanismsareinterfacedwiththehullunit
controller.Whenthegatevalveisclosed,itmustnotbepossibletolowerthetransducer.
Whenthetransducerislowered,itmustnotbepossibletoclosethegatevalve.
Theinstallationtrunkisnotusedwhenagatevalveismounted.Theinstallationtrunk
isthenreplacedwithatransducerdock.
Procedure
1Denethephysicallocationofthemountingange.
2Cutoutaholeinthevessel’shullwithadiameterlargeenoughtoaccommodatethe
mountingange.
3Orientatethemountingangecorrectly,andwelditintoposition.
4Installthegatevalveontopofthemountingange.
5Installthetransducerdockontopofthegatevalve.
6Dependingonmechanicalsupportprovidedbytheexistingdecksand/orbulkheads,
design,manufactureaninstalladditionalmechanicalsupportforthetransducer
dock.
7Ifrelevant,installthehydraulicsystem.
8Doaclosevisualinspectionofthemountingange,gatevalveandtransducerdock
toverifythequalityoftheinstallationwork.
SimradST90InstallationManual