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SeaTech Solutions International (S) Pte Ltd

LIFTING OPERATIONS

The maximum heeling moment developed by multiplying the weight of the hook load andboom by the horizontal distance to port or s d of the hook load and boom center of gravityfrom centerline, considering the full range of crane elevations and weights, is to be

determined. The resulting heeling moment is to be converted to a heeling arm at zerodegrees of inclination by dividing by the barge's displacement. The heeling arm thusachieved is to be superimposed on the righting arm curve and is to be taken as ahorizontal line.

The righting arm curve is to be corrected for the increase in the vertical center of gravitydue to the load

6. Then:

(a) For any condition of loading, the first intercept of the heeling armcurve with the righting arm curve (equilibrium point) is to occur priorto submergence of the deck edge.

(b) The residual area between the first intercept and the angle of

downflooding, the second intercept or 40, whichever occurs first, isnot to be less than 0.03 meter-radians.

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It is nesecery to check that the counterballast provided for each lift is sufficientto withstand the sudden loss of the hook load in each condition ofloading and operation. For details of how this requirement is to beassessed see page no 9

The free surface effects are to be considered for those tanks, which areballasted.

Counter Ballasting

The following Crane Operating criteria is used along with IMO Pontoon Criteria

during crane operation conditions

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HM(1) = the heeling moment curve due to the combined heelingmoments of the hook load and the counterballast at thedisplacement with hook load.

HM(2) = the heeling moment curve due to the counterballast atthe displacement without hook load.

c = the angle of static equilibrium due to the combined hookload and counterballast heeling moments.

f = the downflooding angle on the counterballasted side ofthe vessel.

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