Download presentation
Presentation is loading. Please wait.
Published byBonnie Lang Modified over 9 years ago
1
DL 105 Marine Survival Davits BT Elliott 2011
2
Davits A system to move a lifeboat from the stowed position, outboard for launching and recovery Davits A system to move a lifeboat from the stowed position, outboard for launching and recovery Radial Obsolete Mechanical Obsolete Gravity
3
Radial Davits Manually swung out, first one then the other, manila falls, two person operation
8
Mechanical Davit Hand cranked out, manila falls, 2 man op.
11
Gravity Davits Industry Standard One man operation Wire rope falls No power needed to launch Brake controlled lowering speed Electric winch for hoisting Manual cranking gear with safety device Launch able with vessel listing and trimming
13
Types of Gravity Davits Roller Gravity Single Pivot Multi-Pivot Free-Fall Fixed
14
Roller Gravity
17
Single Pivoting
19
Multi-Pivoting
20
Multi-Pivoting Used when height is restricted, deck above
22
Free Fall
24
Fixed Drill rigs, no concerns about listing and trimming
25
Training Ship Lifeboats 1, 2, 3, 4 use Roller Gravity Davits Lifeboats 5, 6 use Single Pivot Gravity Davits
26
Roller Gravity Davit Lifeboats #1, 2, 3, 4
27
Pivoting Davit Lifeboats # 5, 6
28
Roller Gravity Davits Most common on TSGB Style of Davit that the USCG is basing their testing on
29
Main Components Track way and Davit Arm
30
Track Way Each supports and guides an arm Transfers weight and forces to ship Provides mounting surfaces accessories such as winches, grips, locking bar and limit switch
31
Davit Arm Moving part of system using rollers Cradles lifeboat Attachment point for wire sheaves, span wire and tricing pendent
32
Electric Winches Not needed to launch Track way or Deck Mount Closed gearing 2 Drums Centrifugal Brake 120 ft/minute maximum Dead Man brake Overhauling Wheel Emergency cutoff switch Operating Controls on Rail
33
Drums Sized for 6x19 wire, Fleet Angle ≤ 8۠
34
Davits 1, 2, 3, 4 Centrifugal Brake Dead man Brake Manual Cranking with Safety device Overhaul Wheel
35
Emergency Cutoff Operating Controls
36
Gripes Secures lifeboat to Davit Arm in stowed position
42
Tricing Pendent: brings boat alongside for loading Frapping Line: replaces tricing and controls boat while lowering
46
Limit Switch Cuts power to winch before final Securing
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.