Lifting Equipment Types: Understanding Hoists, Cranes, Slings, And Accessories
Sling types, accessories, and load-handling methods related to hoists, cranes, slings, and accessories
Sling types commonly used with hoists and cranes include wire rope slings, chain slings, synthetic web slings, and round slings. Each material class has distinct mechanical properties: wire rope offers high abrasion resistance and heat tolerance; chain slings provide durability and can be repaired by replacing links; synthetic slings are lightweight and gentler on finished surfaces but may be more susceptible to cuts and chemical exposure. Selection often depends on load weight, temperature, surface condition, and the required sling angle, all of which influence sling tension and effective capacity.
Lifting accessories such as shackles, swivels, hooks with safety latches, spreader beams, and lifting magnets expand handling options and change load distribution. For multi-leg sling arrangements, spreader beams or lifting frames may be used to reduce sling angle and lower stresses in sling legs. Shackles and connecting links are typically specified by their rated working load limit and must match sling hardware ratings. Accessories add complexity to load charts and require attention to bearing surfaces and pin integrity during inspections.
Rigging techniques affect load stability and equipment loading. Sling angles influence tension in legs: as sling angle decreases from vertical, tension in each leg often increases, which can substantially reduce allowable load per sling. Center-of-gravity assessment and use of tag lines or load restraining methods can control rotation and reduce collisions during transit. For irregular loads, riggers may use choker hitches, basket hitches, or bridle arrangements, selected based on balance and contact area to minimize slippage or damage.
Inspection practices for slings and accessories generally involve checking for deformation, corrosion, broken wires or stitches, damaged fittings, and proper identification tags. Synthetic slings are checked for cuts, abrasion, and chemical attack; wire rope for broken wires and core issues; chain slings for elongation and cracked links. Many jurisdictions and standards bodies recommend specific inspection intervals based on service frequency and exposure; maintaining clear records supports consistent replacement and retirement decisions.