This Mawdsley’s DC motor was originally sold to a Plastics Engineering Company in 1999, for the manufacture of Packaging materials. Its basic rating is 28.9kW at 1760rpm when supplied with 460 volts to the armature.
The motor developed a fault and was sent to us for further investigation. Our Engineers found several issues needing attention, but the primary cause for the motor failure was a failed shunt field circuit. To correct this, a new set of 4 field coils had to be wound and fitted.
The frame and field assembly was steam cleaned to remove carbon and then stoved until it was thoroughly dry. The new coils were fitted and the complete frame and field assembly was dipped in insulating varnish and baked.
The motor received a full overhaul including commutator skim and undercut. New carbon brushes and bearings were fitted during re-assembly, prior to final testing.
This is one of many similar motors that were sold into the Plastics Industry for extruders, injection moulding and processing equipment. These DC motors continue to give good service life and can be repaired to ‘as new’ condition.