Electric motors for OEM and Middle East markets

25 May 2010

Weg’s NEMA W22 range of High and Premium efficiency three-phase electric motors offer the highest levels of energy efficient performance, reducing losses by between 10% and 40% when compared with competitive motor types. Designed in 2, 4, 6 and 8-pole configurations, the NEMA W22 motors exceed the requirements of the new IE2 (EFF1) High Efficiency, and IE3 (Premium) efficiency classes.

Electric motors for OEM and Middle East markets

Key to their improved energy performance is a new aerodynamic frame, which increases airflow and reduces operational temperatures, and also a repositioned motor terminal box, which optimises airflow over the motor.

The W22 NEMA range of 60-Hz motors is initially available in frame sizes from 364T to 587T, with progressive introductions of smaller frame sizes during the next year. Providing a package which delivers significantly lower energy consumption, lower noise and vibration, higher reliability, easier maintenance and lower cost of ownership, the range will appeal to export OEMs selling into North America and its environs, Canada, and also the Middle East, which uses large numbers of NEMA motors in its oil production activities.

The redesigned cooling system at the heart of the W22 design, not only improves energy performance across the life of the W22 motors, the increased airflow it generates across the motor also means fewer hotspots, and, therefore, higher reliability. In addition, lower temperatures further enhance the benefits of Weg ´s WISE insulation system (international patents pending), which offers high resistance to temperature degradation. The exclusive WISE insulation system increases the dielectrical resistance of the W22 windings, allowing VFD operation up to 575V, without any requirements to modify the W22 motor.

The lifetime of the W22 motors is also improved through the use of a robust cast iron (FC-200) frame, which is the same class as Flameproof, and offers high resistance to corrosion. The frame is designed to improve heat exchange and provide high levels of mechanical strength to cater for the most critical applications.

In addition, protecting the motor is Weg’s WSeal, which offers improved protection through a ‘V’Ring with double lip and metallic cap, and the motor casing, for example, is constructed from cast iron FC-200, which is the same class as Flameproof and which offers high resistance to corrosion.

The product also features solid integral feet which offer high mechanical stiffness and easy alignment, while a reinforced fan cover provides higher impact resistance. Maintenance of the product is simplified through features such as longer lubrication intervals and a fast-on fan assembly.

Another innovation introduced by the W22 is the terminal box. Positioned at the front of the frame to improve airflow, the box has also been redesigned to allow easier cable handling, better connection and flexible mounting (top/side). It also provides more space for accessories.