Special motor with 10-ton rotor for steel mill – Menzel Elektromotoren

By provisioning preventative maintenance programs in good time, plant operators avoid costly downtimes. This is all the more important for non-standard configurations. An Argentinian steel mill operator commissioned Menzel Elektromotoren to build a special motor based on an existing motor having the type of construction IM 7311. In order to future-proof and since this is a considerable investment, the old, still operational motor is to be stored as backup. Therefore, the new machine must replicate it in every detail, although, due to modern design techniques, Menzel implemented a performance increase at the customer’s request.

The new slip ring motor provides a nominal torque of      43245 Nm at 6600 V rated voltage and 1345 kW rated power. The format is unusual: at a total weight of 21.9 tons, the rotor alone weighs full 10.4 tons. Various accessories were installed, including HALL effect current transformers to measure the rotor current, customer-specified accelerometers on the bearings, and a level sensor for the electrolyte in the starter. The motor features IP23 protection and IC 01 cooling (open-circuit ventilation). It has to withstand ambient temperatures up to 45 °C in the rolling mill.

The German, family-run company counts special motors among its core business and also designed the starter in such a way that it caters for the new motor and the original one equally. Before shipping, the motor underwent a complete type test with additional tests according to customer specifications, including partial discharge and dissipation factor measurement (tan δ). Menzel will also handle the mill drive commissioning, which the operator will schedule to suit production planning.

More information about customized motors: https://www.menzel-motors.com/modification/

Caption: The customized motor replaces an old model in the steel mill