An alligator shear, sometimes called a crocodile shear, is a metal-cutting shear with a hinged jaw, powered by a flywheel or hydraulic cylinder. Alligator shears are generally set up as stand-alone shears; however, there are types for excavators. The jaw size can range from 4 to 36 inch (100 to 910 mm) long. They are generally used to cut steel members, such as rebar, pipe, angle iron, or I-beams.
Operation
Older alligator shears were powered by a flywheel. These shears ran continuously, which posed a safety hazard. Now alligator shears are hydraulically actuated. When actuated, the piston arm extends and slowly closes the upper jaw of the alligator shear, which passes alongside the bed or lower jaw of the shear to perform the cut.
Uses
Alligator shears are used for cutting long metal stock or scrap, generally where accuracy is not an important consideration, and the size or shape of the material makes other cutting or shearing options impractical- often the only other cutting option is cutting with a torch. Alligator shears are often used in conjunction with large metal shredders in the metal recycling industry, to 'clean' or prepare scrap for shredding by removing unwanted fittings or other parts the shredder will not accept.