The sling, like many other technologies, has roots in warfare. Constructed in various forms since the dawn of civilization, slings were archaic missile launchers, firing projectiles with the energy that one could generate by swinging a rope. In the Modern Age, however, the quick and easy conversion of potential energy to kinetic energy by slings has increased the efficiency of numerous industrial practices needing to handle and transport heavy loads. However, if slings are faulty, injuries and even fatalities can result. Therefore, inspection and proper use of slings while considering their environmental conditions remain crucial.
Development of Slings in ASME B30
Since 1971, slings have been specified in ASME B30.9. This is actually a “chapter” or “volume” of the overarching ASME B30 standard. Developed by the ASME B30 Standards Committee, this “Safety Standard for Cableways, Cranes, Derricks, Hoists, Hooks, Jacks, and Slings” contains a range of provisions for the construction, installation, operation, inspection, testing, maintenance, and use of cranes and other lifting and material-movement-related equipment.
About ASME B30.9-2021
ASME B30.9-2021: Slings, an American National Standard (ANS), is the latest edition of this volume of the industrial safety standard. Its provisions apply to the fabrication, attachment, use, inspection, testing, and maintenance of slings used for load-handling purposes. For the most part, these slings are used in conjunction with equipment described in other volumes of ASME B30.
Specifically, ASME B30.9-2021: Slings addresses slings fabricated from alloy steel chain, wire rope, metal mesh, synthetic fiber rope, synthetic webbing, and polyester and high performance fiber yearns in a cover (or covers).
ASME B30.9-2021 revises and supersedes the 2018 edition of the same standard. Among its revisions, this new edition saw the following changes of note:
- Added new Nonmandatory Appendix A, “Sling Protection.”
- New definition for endless sling (alloy chain).
- Updated sections that address proof test requirements, rated loads, and operating practices.
Changes to ASME B30.9-2021
The previous edition of this standard, ASME B30.9-2018, was a substantial revision. Updating the 2014 edition of the same standard, this edition underwent the following changes:
- Added definitions for denier, high tenacity fiber, original language(s), shall, should, and tenacity.
- New section on “Rigger Responsibilities.”
- Section on “Original and Translated Technical and Safety-Related Information” revised entirely.
- Clarified that a qualified person should, if necessary, determine additional steps that need to be taken after identifying a hazard during inspection.
- Added guideline that slings in severe or special service should be inspected before each use.
- Added guideline for maintaining a written record of the most recent periodic inception of slings.
- Added guidelines for finishing fitting surfaces to remove edges in clause on wire rope, synthetic rope, synthetic webbing, metal mesh slings, and polyester roundslings.
- Added new section on sling components that employ wire rope slings other than those listed in the standard.
- Added new section on methods of fabrication for wire rope slings.
- Removed guideline prohibiting slings made with wire rope clips being used as a choker hitch.
- Clarified that a polyester roundsling does not need to be removed due to knots in the roundsling when there are core yarn knots inside the cover installed by the manufacturer during the fabrication process.