Design, Construction, and Manufacture of Squirrel Cage Rotors

This chapter presents the essential features of the design, construction, and manufacture of squirrel cage induction rotors. It provides knowledge for industrial engineers, who use Motor Current Signature Analysis (MCSA) to determine if there are any cage winding breaks in their squirrel cage induction motors (SCIMs). Die‐cast windings are used because they are much less expensive to manufacture and more intricate and variable bar shapes can be obtained, since the bars take the form of the slots in the rotor core. The bars in copper or copper alloy windings are most commonly connected to the shorting rings by brazing them together, but some manufacturers have used a tungsten inert gas (TIG) welding process. The chapter summarizes squirrel cage winding design and manufacturing features that should minimize catastrophic failures that can cause consequential damage to other motor parts, including the stator winding.