The Mazzella DOG grade 80 alloy steel double, fixed-leg welded chain sling has an oblong master link and a foundry hook on each of the two legs for lifting loads with a two-point bridle configuration in abrasive and high-temperature environments such as foundries and steel mills. This chain sling is made of grade 80 alloy steel, which is suitable for applications that require a lower load capacity than that of a grade 100 alloy steel chain sling. It has greater temperature and abrasion resistance than a web or wire rope sling. The sling has an oblong master link at the top of the sling and a grab hook on each of the two chain legs for two-point bridle lifting configurations. The length of the two legs extending from the master link cannot be adjusted, and the grab hooks have a narrower opening than foundry hooks or sling hooks for connecting to a chain link. The welded construction of this chain sling is more durable than mechanical construction. A chain sling does not stretch at its maximum load capacity, but it can stretch up to 20% before its breaking point, to provide shock resistance. This sling meets American Society of Mechanical Engineers (ASME) specification B30.9 and Occupational Safety and Health Administration (OSHA) specification 1910.184.
Slings are used to lift heavy objects for industrial applications. Types of slings include web slings, wire rope slings, chain slings, and mesh slings. The appropriate type of sling for an application depends on the strength-to-weight ratio, flexibility and resistance to bending, resistance to abrasion and cutting, resistance to crushing, resistance to stretching, and resistance to high temperatures and other environmental stressors. Slings have one, two, three, or four legs. Legs are support branches that extend from a single point at the top of the sling to the item being lifted so the weight of the load is distributed evenly among the branches. Slings have eyes (loops) or alloy steel fittings on the ends.
A vertical lifting configuration connects a crane hook directly to a load with a single, vertical sling, usually by means of a hook. In two-point, three-point, and four-point bridle configurations, the sling attaches to the load at two, three, and four locations, respectively, in such a way that each leg is at the same angle to the load. Load capacity is the maximum weight to be lifted in either a vertical configuration (single-leg slings) or at a 60-degree angle (two-, three-, and four-leg slings). A chain sling's capacity at a 45-degree angle is approximately equal to the 60-degree capacity times 0.8, and its capacity at a 30-degree angle is approximately equal to the 60-degree capacity times 0.57. For example, a chain sling with a capacity of 2,000 lb. at a 60-degree angle will have an approximate capacity of (2,000)(0.8)=1,600 lb. at a 45-degree angle and an approximate capacity of (2,000)(0.57)=1,140 lb. at a 30-degree angle.
Mazzella Lifting Technologies manufactures lifting solutions including slings, cranes, and hoists. Founded in 1954, the company is headquartered in Cleveland, OH.