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 29 of 84 6.3 LIFT POINT LOADS 6.3.1
The basic vertical lift point load is the load at a lift point, taking into account the Design Weight as given
in Section 6.2.1 proportioned by the geometric distance of the centre of gravity, accounting for
Where a CoG envelope is used (see Section 8.4.1 of 0001/ND, Ref. [1]), the lift point loads
should be calculated for a CoG position at the extremes of the CoG envelope. For twin hook
lifts, the effect of tilt / hook elevation tolerances given in Section 5.4 should be accounted for.
Where no CoG envelope is used, the lift point loads are to be increased by the factor given in
Section 8.4.3 of 0001/ND, Ref. [1]. For twin hook lifts, the effect of tilt / hook elevation
tolerances given in Section 5.4 should be accounted for.
The basic lift point load is further increased by the following factors (as listed in Figure 5-1) as
appropriate for the lifting arrangement under consideration:
Dynamic Amplification Factor (see Section 5.5)
Yaw Factor (see Section 5.4.7) for twin hook lifts
Skew Load Factor (see Section 5.6)
Additional Factors (see Section 5.7.1)
6.3.2
If the lift points are at different elevations as shown in
Figure 6-1 then sling forces shall be resolved at the sling
intersection point, IP, which will be above the hook
(if connected directly to the hook) or, if connected to a
shackle /sling system suspended from the hook, the IP
will be above the connection point on the shackle. The
design sling loads should consider a CoG envelope and
the loads in the slings determined by positioning the
extremes of the CoG envelope under the IP and the sling
loads recalculated using the new sling angles α and β.
