Chain slings are known for their durability and they are one of the toughest categories of rigging. Industrial lifting slings that are made up of chain guarantee better performance compared to polyester round slings, nylon web slings, and twin-path slings. Much preferred for their adjustability, chain rigging slings exhibit better temperature tolerance and cut resistance. Notably, the chain is manufactured in various grades. The strength of the rigging chain is indicated in terms of the lifting chain’s grade number and the larger grade number indicates greater chain strength. Chains numbered as Grade 30 or Grade 40 are often found at hardware stores and they can be used safely for segmenting parking lots, but they are not fit for use in serious lifting operations.
Trucking and transportation companies normally use Grade 70 transport chains to tie down loads, but such tie-down-chains should never be used as rigging applications. Chain slings with grades 80, 100, and 120 can only be used for lifting purposes in industrial settings. This is mainly due to the fact that the metal used to make these slings demonstrates a strong capability to stretch and elongate. This becomes one of the major considerations when annual inspections are conducted to measure chain slings. These days, most rigging chain manufacturers have started focusing on manufacturing grade 100 lifting chains that are stronger yet lighter than grade 80 rigging chains.
Chain slings come in standard form as well as with custom-made fittings that are designed to suit specific conditions. The manufacture of chain slings is governed by industry standards that demand proof-testing and certification of all individual components that are used in the fabrication of rigging chains. Popularly, alloy steel is used to manufacture chain slings that are used for overhead lifting applications. Stringent quality control techniques are applied to 8600 series alloy before it is approved for use in overhead lifting operations. Alloy steel chains demonstrate the appropriate strength, mechanical properties, and chemical content that is required to adhere to the industry standards. The standards require chain slings to have minimum proof-test and elongation values and require chain slings to bear specifications regrading minimum statistical breaking strengths and working load limits.
It is critical to be able to distinguish alloy steel from other popular grades of welded chain and you can identify alloy chain through its hallmark or identification code that normally comes engraved into chain links. Make sure that you do not use chain slings for overhead lifting unless you verify that it is made out of alloy steel.