0027-nd rev 11.2 8-jul-16 guidelines for marine lifting and lowering operations
GUIDELINES FOR MARINE LIFTING & LOWERING OPERATIONS 0027/ND Rev 11 Page 63 of 84 18.1.9
The following parameters should normally be monitored manually/visually or by monitoring systems if
needed to obtain sufficient accuracy and/or to ensure adequate response time:
hook load(s)
crane radius
crane slew angle
crane boom angle
crane block elevation
environmental conditions
tilt of lifted object, especially for multi-hook lifts
relative motions of lifted object
position and orientation
clearances
hoisting or lowering velocity.
18.1.10
When evaluating a subsea operation, the relevant of the parameters listed below should be taken into
account prior to establishing the operation and design criteria for inclusion into the operating manual:
water depth
tide
on bottom visibility
accuracy of survey equipment
available current data
wave/wind statistics for area in question
the expected operation reference period
expected time to reverse the operation
type of operation
contingency procedures, e.g. retrieval or abandonment of object
type of installation vessel/equipment
weather forecast and monitoring uncertainties
vessel response characteristics
deck handling/over-boarding restrictions
type of lifting gear
crane capacity and specifications
weight of crane wire (in deep water)
crane tip motion
crane hoisting/lowering speed
hydrostatic and hydrodynamic effects (air filled structure or not)
entrapped air
submerged weight
tugger line forces
operational restrictions on tugger line disconnection
guide wire forces and winch speed limitations
soil conditions, soil properties and seabed topography
load reducing systems (heave compensation capacities)
vessel DP capability /position keeping systems
ROV station keeping capability and working range
complexity of ROV tasks (e.g. ROV Interfaces on structure).
18.1.11
For operations requiring the removal of old installations, it shall be documented that no hazardous
material is present which could cause an issue to the safety of personnel (e.g. cutting operations at
locations where lead based paint has been used, asbestos fire proofing has been used etc.). Where a
hazardous material has been identified, procedures are to be implemented to ensure that safety of
personnel and the environment is not compromised.
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