The Anatomy of an Alloy Chain Sling Failure

//The Anatomy of an Alloy Chain Sling Failure

Contributed by Bob Kozickie, Technical Sales Support Manager

Alloy steel chain slings are the most durable products used for lifting and rigging. So, why do alloy chain slings fail? Every year we read and hear stories of catastrophic chain sling breaks. When these failures happen, the broken sling components are then sent back to the sling manufacturer or an independent third party for detailed examination, testing, and laboratory analysis. The resulting failure analysis report frequently comes back to one of a short list of conclusions. We will take a look at some of the most common reasons that these incidents occur.

The first reason to look at why a chain sling failure occurs is due to failure to inspect. OSHA 1910.184 states that alloy steel chain slings shall be inspected on a daily basis by a competent person as designated by the employer. Employers are also required to have a documented written inspection for every alloy chain sling at intervals not greater than once every 12 months. These records must also be made available for examination. Chain sling inspections may be required to be inspected on a more frequent basis depending on frequency of use, the severity of service conditions, and the nature of lifts being made. Inspections detect sling component areas where the criteria for removal are noted. Alloy chain slings that have remained in service for extended period of time without being thoroughly inspected are most susceptible to failure.

Ensuring that a Lift Plan, Risk Assessment, and Load Control are followed will significantly reduce the possibility of a chain sling failure. A qualified or certified rigger knows the specific information they need to have in order to properly and safely lift their loads. The key facts are the weight of the load, number and locations of the attachment points, amount of headroom, and the center of gravity (COG). Failure to take the time to verify these key pieces of data can result in a catastrophic chain sling failure. This, in addition to using industry approved and properly inspected rigging hardware components, will minimize the risk of the sling failure. Many times riggers have used componentry or grades of chain other than grade 80 or 100 to lift their loads. Grade 80 and 100 is the only chain and attachments approved for overhead lifting by OSHA, ASME, and manufacturers’ recommendations.

The remaining common reasons that alloy steel chain slings fail is abuse and misuse. These can include: overloading the rated sling capacity, twisting the chain or tying it in knots to shorten a leg, failure to store the slings properly, not padding the corners of sharp loads, and dragging chain slings across a concrete floor among other possible conditions. Respect for rigging leads to higher safety standards for the company, employees, co-workers, property, but most of all yourself and your family!

There are a number of steps that we can take to limit the possibility of an alloy steel chain sling failure from occurring. The first step is performing a daily sling inspection to help to catch a damaged sling between the required annual inspection intervals. Taking the time to properly prepare a Rigging Plan will significantly reduce the chances of any rigging failures. Finally, extensive knowledge and understanding of basic safety information, proper training, and safety education all result in a safer work environment.

June 4th, 2018|