Motor Rewinds from Morris Renew Crane Motors

Morris Material Handling, Oak Creek, Wis., offers motor rewinds to renew crane motors affected by age and usage. The service can revive original performance and quality, enhance reliability, and extend the life of the crane motor.

Instead of reverse engineering the motor, which can lead to performance loss, Morris’s motor rewinds restore the crane motor back to its original condition. Insufficient analysis of the motor can result in defective rewinding, leading to a pattern of frequent and premature motor failures. Experienced technicians analyze and pinpoint causes of failure through a 50 point repair summary. The motor is then returned to its original performance standards by repairing and replacing components according to the requirements of the specific motor, including correct wire size, sufficient varnish adhesion and insulation, correct end turn tension, and adequate assemblies.

Crane motors experience repeated stress, such as extreme temperature changes, abrupt starts, stops, and changes in direction. These external factors will degrade the components of the most rugged motors. Morris determines the proper specifications for the motor and restores components to original performance, enabling the motor to withstand external stresses with a reduced failure rate. Windings are stripped, all remnants of old laminations are removed, and the wire is replaced with new wire that is appropriate for the crane application. Using the correct wire gauge and type prevents excessive resistance, poor performance, and premature motor failure. All slots are hand cleaned to ensure proper seating and fit of new wire. To prevent wire abrasion and insulation failure, the stator and rotor of the rewound motor are dipped in varnish or epoxy repeatedly, according to the proper adhesion requirements of the original specifications.

Unlike other rewind service providers, Morris Material Handling replaces, rather than repairs, damaged shafts to avoid possible stress points that shorten motor life. Engineers test the motor for core loss and, if necessary, replace it with proper laminations and stack heights. Laminations are hand-stacked to ensure proper stacking and precise alignment. End turns are banded at the proper tension to prevent loosening and abrasion that can lead to short circuits. Brush holders and slip ring assemblies are replaced, instead of repaired or cleaned, to ensure adequate tension.

Motor rewinds from Morris Material Handling apply Class H Insulation, enabling motors to withstand higher temperatures. All motor rewinds are completed with a superior insulation system achieved through the vacuum pressure impregnation process, which ensures maximum penetration of resin throughout the rotor coils, stators, and end turns to further extend motor life, even in the highest moisture and corrosive environments.