Post on 12-Jan-2016
DL 105DL 105Marine SurvivalMarine Survival
DavitsDavits
BT ElliottBT Elliott
20112011
DavitsDavits A system to move a lifeboat from the stowed A system to move a lifeboat from the stowed position, outboard for launching and recoveryposition, outboard for launching and recovery
Radial Radial ObsoleteObsolete
Mechanical Mechanical ObsoleteObsolete
GravityGravity
Radial DavitsRadial DavitsManually swung out, first one then the other, Manually swung out, first one then the other, manila falls, two person operationmanila falls, two person operation
Mechanical DavitMechanical DavitHand cranked out, manila falls, 2 man op.Hand cranked out, manila falls, 2 man op.
Gravity DavitsGravity Davits Industry StandardIndustry Standard One man operationOne man operation Wire rope fallsWire rope falls No power needed to launchNo power needed to launch Brake controlled lowering speedBrake controlled lowering speed Electric winch for hoistingElectric winch for hoisting Manual cranking gear with safety deviceManual cranking gear with safety device Launch able with vessel listing and trimmingLaunch able with vessel listing and trimming
Types of Gravity DavitsTypes of Gravity Davits
Roller Gravity Roller Gravity
Single PivotSingle Pivot
Multi-PivotMulti-Pivot
Free-FallFree-Fall
FixedFixed
Roller GravityRoller Gravity
Single PivotingSingle Pivoting
Multi-PivotingMulti-Pivoting
Multi-PivotingMulti-PivotingUsed when height is restricted, deck aboveUsed when height is restricted, deck above
Free FallFree Fall
Free FallFree Fall
FixedFixedDrill rigs, no concerns about listing and Drill rigs, no concerns about listing and trimmingtrimming
Training ShipTraining Ship
Lifeboats 1, 2, 3, 4 use Roller Gravity DavitsLifeboats 1, 2, 3, 4 use Roller Gravity Davits
Lifeboats 5, 6 use Single Pivot Gravity Lifeboats 5, 6 use Single Pivot Gravity DavitsDavits
Roller Gravity DavitRoller Gravity DavitLifeboats #1, 2, 3, 4Lifeboats #1, 2, 3, 4
Pivoting DavitPivoting DavitLifeboats # 5, 6Lifeboats # 5, 6
Roller Gravity DavitsRoller Gravity Davits
Most common on TSGBMost common on TSGB
Style of Davit that the USCG is basing their Style of Davit that the USCG is basing their testing ontesting on
Main ComponentsMain ComponentsTrack way and Davit ArmTrack way and Davit Arm
Track WayTrack Way
Each supports and Each supports and guides an armguides an arm
Transfers weight and Transfers weight and forces to shipforces to ship
Provides mounting Provides mounting surfaces accessories surfaces accessories such as winches, such as winches, grips, locking bar and grips, locking bar and limit switchlimit switch
Davit ArmDavit Arm
Moving part of system Moving part of system using rollersusing rollers
Cradles lifeboatCradles lifeboat
Attachment point for Attachment point for wire sheaves, span wire sheaves, span wire and tricing wire and tricing pendentpendent
Electric WinchesElectric WinchesNot needed to launchNot needed to launch Track way or Deck MountTrack way or Deck Mount Closed gearingClosed gearing 2 Drums2 Drums Centrifugal Brake 120 Centrifugal Brake 120
ft/minute maximumft/minute maximum Dead Man brakeDead Man brake Overhauling WheelOverhauling Wheel Emergency cutoff switchEmergency cutoff switch Operating Controls on Rail Operating Controls on Rail
DrumsDrumsSized for 6x19 wire, Fleet Angle Sized for 6x19 wire, Fleet Angle ≤≤ 8 8 ۠۠
Davits 1, 2, 3, 4Davits 1, 2, 3, 4
Centrifugal BrakeCentrifugal Brake
Dead man BrakeDead man Brake
Manual Cranking with Manual Cranking with Safety deviceSafety device
Overhaul Wheel Overhaul Wheel
Emergency Cutoff Emergency Cutoff Operating ControlsOperating Controls
GripesGripesSecures lifeboat to Davit Arm in stowed positionSecures lifeboat to Davit Arm in stowed position
Tricing Pendent: brings boat alongside for loadingTricing Pendent: brings boat alongside for loadingFrapping Line: replaces tricing and controls boat Frapping Line: replaces tricing and controls boat
while loweringwhile lowering
Limit SwitchLimit SwitchCuts power to winch before final SecuringCuts power to winch before final Securing