|
Summary:
Avoid unsafe rigging and lifting practices With
trilingual summary
By
Richard L. Nailen, EA Engineering Editor
Lifting heavy electrical equipment, either components
or complete assemblies, is necessary in service centers as well as
other industrial settings. Perhaps because most hoisting apparatus
in small shops handles loads weighing no more than 1000 kilograms,
safety standards governing lifting practices are often ignored,
resulting in damage or personal injury.
Essential to
lifting safety are:
1) proper
condition of the slings- chains, ropes, or woven webs-used to
suspend the load;
2) correct
attachment of slings to the load;
3) safe hoist
operator techniques.
Proper use of
slings involves, first, choosing the right type of sling for the
job. Some slings are unsuited to sharp edges on loads. Others may be
damaged by heat or chemicals present during lifting. To be avoided
are improper splices, knots, and defective hooks or other fittings.
Secondly, in
the United States, Occupational Safety and Health Administration
regulations and hoist industry recommendations call for slings to be
inspected for defects prior to each use. More thorough inspection,
at least once a year, is also required for alloy steel chain slings.
Cuts or tears in woven webs; kinks in wire rope; bent or elongated
chain links—all are cause for rejection.
Finally,
attaching slings to loads (the process known as "rigging") is also
subject to numerous safety rules, such as:
1. When
multiple slings are used, equalize the loading on each of them.
2. Avoid sling
attachment that could allow the load to tip or spin.
3. Make sure
the sling load rating is adequate, with due allowance for the angle
by which the sling deviates from vertical.
4. Eyebolts,
if used, must be fully threaded into the load, and their rating
reduced when the lifting force is not applied parallel to the
threaded shank of the bolt.
0nce the load is ready for safe lifting, the
operator should raise it a short way, slowly, to check the rigging,
keeping hands away from the slings and hooks. Movement should be in
only one direction at a time. A lifted load should never be left
unattended.
Copyright 2003, Barks Publications, Inc., Chicago.
Reproduction by any means prohibited.
|
