[WRE | SPOTLIGHT]
Removal From Service OSHA specifics that wire rope slings must be removed from service should any of the following conditions become present or should occur:
• Ten randomly distributed broken wires in one rope lay, or five broken wires in one strand in one rope lay.
• Wear or scraping of one-third the original diameter of outside individual wires.
• Kinking, crushing, bird caging, or any other damage resulting in distortion of the wire rope structure.
• Evidence of heat damage, which is evident by wire discoloration, burn marks, weld splatter, etc.
• End attachments that are cracked, deformed, or worn.
• Hooks that have been opened more than 15 percent of the normal throat opening measured at the narrowest point or twisted more than 10 degrees from the plane of the unbent hook.
• Corrosion of the rope or end attachments. Only extreme corrosion is necessary to reject a sling. Light corrosion does not substantially affect the strength of a sling. (Rigging Gear Inspector Levels I & II, 42)
ASME B30.9 has similar standards to the terms stipulated above in addition to the following:
• Bent hooks can be no more than 5 percent over the normal throat openings, measured at the narrowest point from the plane of the unbent hook.
• Any evidence of eye splices that have slipped, tucked strands have moved, or pressed sleeves show serious damage may be sufficient cause to reject a sling.
• A very common cause of damage is the kink which results from pulling through a loop while using a sling, thus causing wires and strands to be deformed and pushed out of their original position. Tis unbalances the sling, reducing its strength.
Should a sling be determined as worn out or damaged beyond use because of any of the aforementioned reasons, the inspector should immediately tag the sling as Do Not Use. Afterwards, the sling should realistically be destroyed as soon as possible by cutting the eye and fittings from the rope with a torch. Cutting the body of the sling is also appropriate. Tis method of destruction should deter another employee from mistakenly using a sling that has been formally retired from service. Any inspection program, however thorough, is of no value if the slings that have been rejected or retired are not disposed of properly. (ASME B30.9-2014, 15)
Repairs According to ASME B30.9, should a sling become damaged and be eligible for repair, a restoration should only be conducted by the manufacturer itself or a qualifying individual with the appropriate experience and certifications. For example, if an end fitting such as a hook becomes bent beyond guidelines, you would need to send that back to the manufacturer regardless if the wire rope sling is in tact and undamaged. All repairs conducted on wire rope slings will require marks, tags, or some kind of proof of its restoration and parts that need
replacement can only be substituted for the same original parts that were used in its manufacturing. Should the wire rope used to craft the sling itself become damaged, it is not to be repaired under any circumstances. For example, if one of the wires is damaged by weld splatter or heat damage, it is simply not possible to remove the one strand of wire and replace it. It’s also not necessarily cost-effective for that matter either. Repairs such as these could be more expensive than what the sling is even worth at that point. When a vehicle is involved in an accident, if the price of repair outweighs the total value of the vehicle, it’s considered totaled. Same principles apply to equipment such as wire rope slings. When repairs are worth more than the equipment itself, it’s time to scrap the wire rope sling. (ASME B30.9-2014, 15) Moreover, if a repair is warranted and completed, a proof test
of its structural integrity should be conducted. With wire rope slings, the proof test is a 200% load test.
Conclusion When and how often you should inspect a wire rope sling are often the subjects of debate. Te amount of usage the wire rope sling receives should equate to an appropriate number of inspections it receives every year. A wire rope sling that’s used a few times a year does not require the same number of inspections as a wire rope sling that’s used more frequently, for longer periods of time, and in compromising environments. A general rule of thumb when it comes to how often you should inspect a wire rope sling, at bare minimum, is once a year. However, if the wire rope sling is used frequently or in severe atmospheres where it could be exposed to extreme temperatures where the sling’s integrity can become challenged, then it’s advisable to inspect the wire rope every month or quarterly at least. It’s also essential to keep written records of when the wire rope was last inspected, so you can have proof of it’s inspection and rest assured when using it. If there was an accident or cause for concern, people will want to see those records. As long as those records match what you’ve been doing, you can protect yourself. It’ll also prevent someone from sending out a wire rope sling that’s unsafe or hasn’t been inspected. Because after all, the most important thing on a jobsite is maintaining safety. Safety must always come first. y
Ken Deheve is the Market Research and Content Writer for Lifting Gear Hire, rental equipment specialists. Learn more about wire rope slings and rigging equipment safety at
http://www.RentLGH.com.
References Cited in this Article: Klinke, Jerry. Rigging Handbook. 5th ed., ACRA Enterprises, Inc., 2016.
Industrial Training International, Inc. Rigging Gear Inspector Levels I & II Resource Manual. Parnell Services Group Inc.
Wire Rope Technical Board. Wire Rope Sling Users Manual. Tird ed., Wire Rope Technical Board, 1990.
ASME. ASME B30.9-2014. ASMe, 2014.
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