Customer Job Reference:
Main 150kW 1400 4Pole crusher motor
JJ Loughran Job Reference:
Job No: 3565C
The Original Brief: JJ Loughran engineers where called to site to investigate why a plant critical 150kW slip ring motor had failed under load. Following on-site tests, JJ Loughran engineers found that due to a line fault to earth, the motor had shorted and was “Burned out”. JJ Loughran engineers disconnected the motor and carried out all appropriate lock off procedures. Motor was transported back to Workshop for evaluation.
As plant downtime was not an option, JJ Loughran where able to supply the customer with an off the shelf temporary replacement 150 kW slip ring motor, while the customer’s original was rewound and overhauled.
The spare motor supplied was installed and commissioned in less than 3 hours, thus keeping customer down time to a minimum.
JJ Loughran engineers initially carried out insulation resistance tests between windings, and windings to earth at 500 Volts. Insulation resistance was found to be below acceptable level.
Motor was dismantled and internal rotor removed from stator. Stator was inspected, as motor was burned out, windings where stripped, and the stator was coated with insulator before new copper coils where formed and installed. Stator was stoved and varnished, slip rings and brush gear assessed and inspected before motor rebuild. New bearings where also installed before motor was reassembled, tested and delivered back to site.