Contributed by Bob Kozickie, Technical Sales Support Manager
Edited by Christy Kutchma, Product & Marketing Associate
All alloy chain sling assemblies are required to be certified by the sling manufacturer, however, not all are necessarily required to be physically proof tested. The proof testing requirements for welded versus mechanically assembled alloy chain slings are not the same.
A proof test does provide assurance that the manufacturing processes were followed correctly and the sling will function safely when used within the parameters of its working load limits. Given the fact that alloy chain slings are lifting heavy loads, usually near people and equipment, this requirement is in best practice to maintaining a safe working environment.
OSHA, the statutory requirement for all lifting slings, states in 1910.184(e)(4) that alloy chain slings shall be proof tested prior to use. This includes any new, repaired, or reconditioned alloy chain slings.
This OSHA Standard goes on to state that this involves all welded components.
This statement may cause some confusion as to the proof testing requirements for both the welded and mechanical alloy chain slings.
CPL or Compliance directives are written instructions for compliance policies and enforcement procedures on certain subjects. These directives are designed to give field offices uniform enforcement of the CFR (Code of Federal Regulation) within OSHA.
Welded Alloy Chain Slings
CPL 02-01-14B, Alloy Steel Chain Sling Proof Testing, references welded alloy steel chain sling assemblies. Guideline Number 1 states “When an alloy steel chain sling is assembled with components that require welding in assembly, the completed sling must be proof tested by the sling manufacturer or equivalent entity, before the sling is used.” This includes all new, repaired, or reconditioned chain slings that have been subjected to a welding procedure during assembly.
The main reason for concern is that when a welded chain sling is assembled or repaired, it involves welding and heat treating processes. These processes can inflict a variety of defects, both human and mechanical, into the components that make up the sling.
The proof test, at twice the working load limit, certifies that the sling will meet the working requirements as stated on the ID Tag.
Mechanical Alloy Chain Slings
CPL 02-01-14B, Alloy Steel Chain Sling Proof Testing, also references mechanical assembled alloy steel chain slings. Guideline Number 3 states that “Proof testing is not required when the sling is made up of components not requiring welding to assemble. The capacity of the sling shall be no greater than the rated capacity of the weakest component. ”
This is the statement that allows assembly and certification of mechanical alloy chain slings without a proof test following assembly. The physical proof test exemption is valid provided that the component manufacturers used within in the assembly all provided certificates of proof test when purchased.
It is also understood that the entities that assemble mechanical alloy chain slings can go above and beyond the requirements of the OSHA Standard and perform a proof test if they desire or it is requested by the purchaser.
All alloy chain slings are required to be proof tested, however, the proof test can come in the form of an actual pull test performed as a completed sling assembly or be certified based on the fact that all components used to assemble the sling had been proof tested prior to assembly. The sling manufacturer is still ultimately responsible for proper tagging and certification.