Overhauling and Reconditioning of Electric Motors

Leong Hing undertakes reconditioning and overhauling of flooded and dirt contaminated motors in harsh environment of all sizes. Below are images of some of the motors which we have done remedial work to restore them to full the original condition.

Reconditioning and overhauling of a 500 HP 8 Pole Teco three phase induction motor weighing about 3.4 tonnes.
In reconditioning of motors, the following works are carried out:
  • Steam cleaner is used, typically in the proportions of 15 to 20 pounds of steam cleaning compound and 1 quart of butyl alcohol to 1,000-gallons of water is used.
  • The coils, windings, and structural members are cleaned until all carbon dust, oil, grease, and foreign deposits are removed.  Clean lint-free cloths are used to check for cleaning effectiveness.
  •  At the conclusion of a wash cycle, the windings are rinsed using hot fresh water. Washing and rinsing cycles are carried out until the machine is clean. 
  •  Immediately after cleaning, rinsing and hand drying, the windings are baked in an oven until they are completely dry. 
  • Upon satisfactory completion of cleaning, drying, and any other authorized repairs, insulation treatment of the rotor and stator windings is carried out
  • The windings are solvent-varnish dipped and baked. Varnishes are of Grade CB per MIL-I-24092/2; an industrial electrical grade polyester solvent-varnish compatible with the original varnish is also used.
  • Vacuum-pressure impregnation is carried out then after. The treated windings finally cured in accordance with the varnish manufacturer’s recommendations.