People who investigate rigging failures for a living say that all lifting devices should be inspected before they are put into service. Taking a minute to check over shackles, slings and hooks to make sure they are safe to use can save lives.
Construction projects are moving faster than ever before, and that means that rigging should be inspected more carefully. “Our trades are much more mobile now,” explains Bradley D. Closson, president of CRAFT Forensic Services Inc., Bonita, Calif. Construction also is hard on rigging gear, typically wearing it out faster than other industries, adds Mike Parnell, president of Industrial Training International Inc., Woodland, Wash.
Rigging experts say the most common failure of synthetic slings is cutting from rubbing against the sharp edges of loads or damaged hardware. Always use edge protectors when lifting with synthetic slings, they say, and never exceed a device’s rated capacity. Before each lift, synthetic slings should be inspected for such common damage as knots, burns, holes, cuts, abrasion, broken stitching, chemical spills and ultraviolet fading. Polyester roundslings, whose sheaths are cut open and its internal, core yarns are exposed, should be thrown out. The best way to dispose of a sling, Parnell advises, is to cut out the eyes. If it is an endless sling, cut it up so that no one else can use it in the future.
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| Damaged web slings, hooks, shackles and wire rope (clockwise) can be deadly. (All images courtesy of Industrial Training International INC) | |
Likewise, wire rope and chain slings are not indestructible. Common problems with wire rope are kinks, crushing, broken strands, improper splicing, heat or slag damage from welding, abrasion, untwisting and corrosion.
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Related Link: Chain slings should be checked for links that are elongated, deformed, twisted, gouged or bent. An easy way to check chain is to stretch the sling out on the ground, take one end of the sling and fold it back against the other end. If the links don’t match up with each other, something is wrong, Parnell says. Also, never drag slings or hardware on the ground to pull a load, he adds.
Hardware, such as hooks and shackles, are also important to inspect for damage. Hooks that have severe metal loss or unusually wide or bent openings should be thrown away. Shackles that are deformed or elongated are ripe for disposal. A common problem is using the wrong bolt, Closson notes. The correct bolt is designed for tension; others can shear under load. Finally, the experts say never use rigging that is missing identification, including load capacity.
