YKK Series Induction Motors

YKK series induction motors are box-type high voltage squirrel cage asynchronous motors with air-to-air closed cooling, manufactured in compliance with IEC international standards. The YKK designation represents high voltage motor adopting box frame and IC611 air-to-air cooling structure. This series is engineered for continuous heavy-duty operation in harsh industrial environments, and it has become one of the most widely used driving equipment for large-scale industrial facilities. The closed internal air circuit separates the motor’s cooling loop from ambient air, effectively blocking dust, moisture and corrosive gas from contaminating windings and core components. This structural feature greatly reduces insulation aging and component fouling, extending service life and lowering routine maintenance workload.

Core Technical Parameters

The motor adopts welded box frame structure, which delivers higher rigidity and excellent vibration resistance compared with traditional cast iron housing. The stator core is stacked with high-performance low-loss silicon steel sheets. Electromagnetic parameters are optimized via finite element simulation to cut iron loss, stray loss and magnetic leakage. Stator windings are processed with vacuum pressure impregnation (VPI). The fully impregnated winding system achieves strong dielectric strength, anti-corona performance and thermal stability, capable of enduring frequent starting impact and transient voltage fluctuation during long-term continuous operation.

The squirrel cage rotor is available in cast aluminum and copper bar designs. Copper bar rotor models possess superior mechanical strength, lower rotor resistance and stable starting performance. They can output sufficient starting torque while limiting starting current, avoiding heavy impact on the factory high voltage power grid. Every rotor assembly goes through high-precision dynamic balance calibration to control vibration and noise within allowable range under full-load working condition. Heavy-duty rolling bearings or sliding bearings are equipped for different power grades. Temperature sensors can be embedded in bearings and stator windings as optional configuration, feeding real-time temperature signals to the central control system for over-temperature early warning.

IC611 air-to-air cooling system is the core advantage of YKK motors. Two independent air loops are arranged inside the unit. The internal circulating hot air exchanges heat with external fresh air through the built-in air-to-air heat exchanger. Since the internal cooling circuit remains sealed, dust and corrosive fumes from workshop cannot enter the motor interior. This design makes YKK motors particularly suitable for cement plants, mines and chemical workshops with poor ambient conditions.

YKK series motors serve multiple heavy industrial sectors. In cement industry, they drive raw material mills, main exhaust fans and kiln transmission equipment. In mining projects, they support ball mills, crushers and large belt conveyors. The motors are also widely used for large water pumps, blowers and compressors in power plants and metallurgical factories. Customization options include explosion-proof modification, anti-corrosion coating, special paint and additional vibration monitoring sensors according to site conditions.

All YKK motors undergo complete factory acceptance tests before delivery, covering insulation resistance test, no-load running test, load test, vibration and noise inspection. Featuring robust structure, stable performance, high reliability and convenient maintenance, YKK series induction motors offer dependable high-power driving solutions for global heavy industry customers with continuous production demands.