Image Credit: DME Company | New Pig Corporation
Lifting slings or sling lifts are material handling accessories for load attachment to lifts, cranes, and hoists. They are used in heavy manufacturing and industrial rigging to ensure the safe handling of materials and the safety of operators.
Specifications for Lifting Slings
Lifting slings come in a variety of materials, including metal chains, metal wire, galvanized aircraft cable, nylon, and polyester. A braided lifting sling provides redundant layers of component slings, ensuring that if one component fails, the others will provide enough lift to ensure the safety of the operator, the payload, and the lifting equipment.
Nylon lifting slings are composed of heavy duty nylon webbing and are used in three different types of sling lifts: vertical, choker, and basket. These lifting slings are attached to a hook or rig using the eye loops on either end of the sling. A nylon lifting sling may also include built-in mechanisms to detect dangerous wear and tear, including color -contrasting inner layers or yarns or fiber optic cables.
Chain slings are lifting slings that consist of a series of interlocked oblong metal rings. A master or end link secures the chain sling to the lifting machinery and can be oblong or pear-shaped. Chain slings can have single or multiple chains and are configured with different hooks on the end, including sling hooks, grab hooks, foundry hooks, or locking hooks. The weight, size, and shape of the object elevated by a sling lift determines whether an operator uses a single, double, or triple chain sling.
Other lifting sling components include sling swivels, jointed components that allow the sling to turn or swivel while lifting. A sling swivel is constructed of two metal loops connected by a free-moving cylinder that allows the loops to pivot. Swivel joints keep chains and wire lifting slings from tangling and come in closed or open eye formations. Open eye swivels must be closed using a hammer.
ASTM A906/A906M - STANDARD SPECIFICATION FOR GRADE 80 AND GRADE 100 ALLOY STEEL CHAIN SLINGS FOR OVERHEAD LIFTING
ISO 3076 - ROUND STEEL SHORT LINK CHAINS FOR GENERAL LIFTING PURPOSES - MEDIUM TOLERANCE SLING CHAINS FOR CHAIN SLINGS - GRADE 8
SAA AS 1438 - ACCESSORIES FOR LIFTING EQUIPMENT - WIRE-COIL FLAT SLINGS