Edit this text for your title Edit this text for your sub-title Presenter name, location, date etc. MEK 4450 Marine Operations Kværner ASA / DNV, Fall 2012

Lift phases Load out Transportation Over boarding Removal of sea fastening Lift up Lifting route Start lowering Splash-zone Slamming Wave impacts Lowering Softer system,- resonance Landing Positioning

Deck layout

Deck area Deck strength Lifting route

Sea fastening Limiting weather criteria (transit, WoW) Low complexity Easy, swift and cost effective installation Swift removal. Minimized need for hotwork during removal

Lifting from deck of vessel

Well defined route of lift. Static capacity of crane (DAF=1.3?) Clearance to ship side Restraining load from unwanted motions Test lift for all complex routings! Vessel ballasting. Vessel roll reduction not to be used. Slewing before luffing. Sufficient analyses performed?

Splash zone

Often dimensioning for crane force Vessel listed towards lifted object Bouyancy reduces mass of object Ballasting of vessel Crane wire tension Sufficient time for air to evacuate No use of AHC Stability of lifted object Internal tanks Air filled compartment

Further lowering Is the total duration understood? Fatigue issues on the load Effects on the crane and wire Load rotation control Increased weight of the wire. Generally no use of AHC Deep water resonance Deep water effects

Landing Position control vs tolerances Position, Heading and Inclination Landing speed Damage module Soil damage (stiff clay) Reduction of tension in crane wire Vessel movement and ballasting Capacity of AHC Disconnection of rigging

Recovery

Rigging connection points Suction effects from seabed Water escapation Crane capacity Load control and means of load motion restraints Sufficient deck space Disconnect rigging Seafastening