High Power Electric Motors from 90 kW | NDR

High power electric motors from 90 kW upwards for shredders and mills

Manufacturers of industrial shredders, hammer mills and crushers work with machines that never run under a constant load. Material enters irregularly, torque peaks are frequent and vibrations are part of normal operation. For this reason, when it comes to high power electric motors, the choice of motor directly affects the reliability of the plant.

NDR offers motors from 90 kW upwards, available from stock. Let’s look at what to consider when choosing a high power motor for a heavy-duty application.

Operating conditions of shredders and hammer mills

A shredder or a hammer mill puts the motor under stresses that differ from those of a pump or a fan:

• starts under load, with high torque required right from start-up;
• sudden overloads when the material resists or jams;
• vibrations transmitted from the machine rotor to the structure and to the motor;
• in inverter-driven shredders, frequent reversals of rotation to free jammed material.

Consequently, the motor must be selected on the actual duty cycle, not just on rated power. We have also covered vibrations in our article “Shredder motors: how to counter vibrations”.

What to check when choosing a high power motor

Before defining the supply, it is worth analysing a few technical points.

Starting torque and overload. The motor must provide the torque needed at start-up and withstand load peaks without tripping the thermal protections.

Duty type. A machine running in continuous duty (S1) is sized differently from one subject to non-periodic load and speed variations (S9).

Bearings. With belt drives the radial load on the shaft is high, so the bearing type on the drive end must be checked.

Inverter supply. If the motor is inverter-driven, winding insulation must be assessed. Insulated bearings can be fitted to protect the motor from shaft currents.

Frame. At these power ratings, a cast iron frame provides the rigidity needed to contain vibrations and maintain alignment.

High power electric motors from stock: why it matters

When a large motor fails, the plant stops and the cost of downtime grows every hour. Likewise, a manufacturer who has to deliver a new machine cannot afford to wait for the motor. Having high power electric motors available from stock reduces these lead times, both for replacements and for new installations.

In addition to high power ratings, the range starts from 0.09 kW and includes 2, 4, 6 and 8 pole motors, also in brake, two-speed, ATEX and UL/CSA versions.

NDR support

NDR works alongside the manufacturer’s technical department in selecting the motor. We analyse the application data, check the available configurations and follow the quotation through to delivery.

Do you design shredders, hammer mills or crushers, or do you need to replace a high power motor? Contact us with your application data: together we will identify the most suitable solution and check availability.