
PUMP FORHYDRAULICSYSTEMS - page7 of71
Installationandmaintenancemanual
ULTRAFLEX
ENGLISH
1.2Warningsforthecorrectproductuse
1PRODUCTDESCRIPTION
1.1Hydraulicsteeringsystemoperation
All ULTRAFLEX hydraulicsteeringsystemsaredesignedinconformitywithUNI-EN-ISO10592 andA.B.Y.C.P21
regulations.AllULTRAFLEX steeringsystemscanoperateattemperatures between-18°C(0°F)and+77°C
(+170°F).All thecomponentsaremadeforthemarineenvironment,usingmaterialsandworkingprocesses
whichofferlonglifeandsafetyunderthemostextremeconditions. Ahydraulicsteeringsystemconsistsof
asteeringpumplocatedonthedashboard,acylindertiedtothe
rudderortotheoutboardorsterndriveengineandtheconnecting
hoses (seepicture).Undernormaloperatingconditions,aturnof
thesteeringwheelwill pumptheoil,whichflowsinthroughthe
hoses tothecylinder,accordingtotheturndirection.Withthe
consequentcylindermovementtheoilwill flowtothepumpthrough
thehoses andatthesametimemoves theengineorthehelmwhich
areconnectedtothecylinder.Thepumpsequippedwithanonreturn
valve, whichpreventsoutgoingfluidfromreturningalongthesame
hose. allowtheoperationofthesteeringsystemswithtwoormore
steeringstations.Thecylindersaredouble-actingandtheycanbe
balancedorunbalanced.Inunbalancedcylindersthetwochambers
havedifferentvolumes andthereforetheyrequireadifferentnumber
ofsteeringwheelturnsandadifferentsteeringwheelrotationeffort
withthe samemovementinthetwo directions. The balancedcylinders
requirethesamenumberofturnsofthesteeringwheeltomovethehelmfromthecentretotheendof
strokeinthetwoopposeddirections.
Awellbalancedsteeringsystemneedsacorrectchoiceofthepumpforthecylinder. ULTRAFLEX produces
differentpumpmodels,whichhavedifferentcapacity(cm3ofoilmovedeachsteeringwheelturn)andfor
eachtypeofinstallation.Whilechoosingthepumpitisimportanttoconsiderthecylindervolume.The
numberofstarboard andportturnsis determinedbytheratio betweenthecylindervolumeandthepump
capacity.
Example:ifthepumphas acapacityof28cm3 [1,7cu.in.]andthecylinderhas avolumeof120 cm3 [7,3cu.in.],the
formulalookslikethis: 120/28=4,2.Accordingly,thesteeringwheelwill turnabout4times beforethecylinder
willcompletelyturnfromonesidetotheother.Incase ofinstallationswithdoublecylindersconnectedin
parallelthecylindervolumemustbeadded.Applicationswithless than4turnsarenotrecommended,as
theyneedahighereffort,also applicationswithmorethan8turnsarenotrecommended,as theresponse
oftheboattosteeris slowly.
ULTRAFLEX steeringsystemsmustnotbeinstalledonraceboats.
All ULTRAFLEX steeringsystemsmustnotbeinstalledonboatsequippedwithengines whose maximum
horsepowerishigherthanthehorsepowerratingapprovedbyboatmanufacturer.
Do notmodifythepumpinanywaytofitittoyourapplication,otherwise thepumpwill nolongeroperatein
safetyanditwillendangertheboatandtheoccupants.
WARNING
WARNING
DANGER
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hydraulichoses
cylinder
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