When a mining operation in Asia commissioned a new ventilation solution for their pit fans in June 2016, Menzel Elektromotoren from Berlin constructed and delivered two special motors within an short reaction time.
The two three-phase squirrel cage motors with 1,700 kW, 992 min-1 and 6,000V required especially adapted housings to match the desired motor dimensions. Since the motors were to be incorporated directly in the tubular fan housing, the connecting cables had to be fed out of the housing.
The spatial limitations posed a challenge to the engineers responsible for the project. The fan wheel, for instance, which weighs in at more than a ton had to be installed directly on the shaft. Despite the fact that this results in high radial and axial loads on the motor bearings, Menzel was able to configure both motors so as to reliably ensure a calculated service life of more than 100,000 hours as requested by the customer.
To this end, the motor manufacturer's engineers implemented an adequate special bearing design in cooperation with the bearing manufacturer. The two pit motors are now ready to operate in the particularly demanding mining conditions.