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Rigging Safe Operating Procedures | Up
Steelworker Volume 02 - Building manual for how to work with steel | Next
Figure 6-60.—Multi-legged bridle sling lifting a load. |
Figure 6-58.—Hoisting with shears.
15. Do not shorten a sling by knotting or using wire
rope clips.
16. Do not inspect wire rope slings by passing bare
hands over the rope. Broken wires, if present, can cause
serious injuries. When practical, leather palm gloves
should be worn when working with wire rope slings.
17. Center of Balance. It is very important that in
the rigging process that the load is stable. A stable load
is a load in which the center of balance of the load is
directly below the hook, as shown in figure 6-59. When
a load is suspended, it will always shift to that position
below the hook. To rig a stable load, establish the center
of balance (C/B). Once you have done this, simply
swing the hook over the C/B and select the length of
slings needed from the hook to the lifting point of the
load.
18. When using a multi-legged bridle sling, do not
forget it is wrong to assume that a three- or four-leg
hitch will safely lift a load equal to the safe load on one
leg multiplied by the number of legs. With a four-legged
bridle sling lifting a rigid load, it is possible for two of
the legs to support practically the full load while the
other two only balance it (fig. 6-60).
6-36
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