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Inspection of Slings | Up
Construction Electrician Basic - Electricity handbook for electricians | Next
Procedures and Precautions for Lifting Operations |
The least sign of binding at the juncture points of
links indicates collapse in the sides of the link caused by
stretching. Such a condition is dangerous, and the chain
should be removed from service.
Spreaders and Pallets
When hoisting with slings, you may often need to
use spreader bars to prevent crushing and damaging the
load. Spreader bars are short bars or pipes that have
eyes fastened to each end. By setting spreader bars in
the sling legs above the top of the load (fig. 1-14), you
change the angle of the sling leg and avoid crushing the
load, particularly the upper portion.
The use of cargo PALLETS in combination with
slings is a big advantage on jobs that involve the
hoisting and moving of small-lot items (fig. 1-15). You
may need to use spreader bars when hoisting pallets to
avoid damaging the pallets and load. The pallet
provides a small platform or board on which a number
of items can be placed and moved as a unit rather than
piece by piece. Palletizing obviously is quicker and
easier than moving each individual item separately.
MOVING MATERIALS AND
EQUIPMENT
The safe movement of equipment and materials
does not just happen. It takes knowledgeable people to
communicate, control, and rig movements. Personnel
safety, undamaged materials/ equipment, and
Figure 1-14.—Use of spreader bars in a sling.
Figure 1-15.—Cargo pallets in combination with slings.
operational efficiency are the responsibility of all
personnel involved.
SIGNALLING
CEs are frequently required to act as signalmen for
crane or hoist operators and for the positioning of
equipment. There are a number of precautions and
procedures that should be observed in these operations.
Whenever the operator’s view is obstructed so that
he cannot see the path of travel of any part of the
equipment, load, or components, a competent
signalman is required to be stationed in such a position
that he or she can be easily seen by the operator and
where the signalman has a full view of the intended path
of travel of the equipment, load, or components, yet
where he or she will be clear of the intended path of
travel. The signalman should assist the operator by
watching the load when it is out of view of the operator
and communicating with the operator by the use of
prearranged visual signals (app. III) or a suitable
communication system.
The signalman must
be fully qualified by experience with the
operation.
wear high-visibility gloves.
use hand signals only when conditions are such
that the signals are clearly visible to the operator.
be made responsible for keeping the public and
all unauthorized personnel outside the operating
radius of the crane or the path of the equipment.
direct the load so that it never passes over
anyone.
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