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WEG introduces SM40 series of synchronous motors

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Hydrocarbon Engineering,

WEG has introduced a new series of robust and efficient synchronous motors, the SM40 series, for the power range from 5 to 35 MW. The motors provide exceptional reliability in demanding applications with extended maintenance intervals, enabling users to reduce servicing costs and increase process uptime. With shaft and rotor made from a single piece of forged steel and high starting torque, the new SM40 is ideal for high-inertia applications including centrifugal compressors in air separation plants or the oil and gas industry, large fans in the steel industry or power plants, and high-power pumps and pulp mills.

The SM40 motor has a robust rotor construction with high mechanical strength and stability, and has been designed to eliminate the risk of detachment of individual pole shoes or pole mounting screws. The stator consists of high-quality, low-loss silicon steel laminations and top-grade bobbin windings insulated using a special vacuum/pressure impregnation (VPI) process while an optimised thermal design ensures uniform temperature distribution along the stator, prolonging the service life of the winding insulation.

The motors have a high starting torque and low starting current enabling users to achieve significant energy savings, which is particularly important in energy-intensive applications. The low starting current also minimises the impact of the motor on the power supply network and means starting aids such as starting chokes, autotransformers or variable speed drives become unnecessary, thus bringing costs down further.

SM40 motors can also help plants reduce power costs and improve the efficiency of the power network to which they are connected because they deliver high efficiency over a wide power range and enable users to correct the power factor. As a result, they deliver a short investment payback time and the SM40 series is ideal for industries where 24/7 operation is the norm.

Equipped with the Sync-Rite synchronisation module, the motors can be optionally configured to allow parameters such as excitation current, voltage and synchronisation status to be read and indicated over a BlueTooth link.

The SM40 motor’s housing is made from welded steel plates and profile sections to ensure high bending strength and robustness. This design enables the motors to withstand substantial mechanical loads and keep vibration levels low, even under high stress. Various housing and cooling options are available for matching the motors to application specifications.

Available in the power range from 5 to 35 MW and in frame sizes from IEC 800 to IEC 1250, the new SM40 high-performance four-pole motors are designed as horizontal synchronous motors with solid salient pole rotors for voltages up to 13.8 kV at 50 or 60 Hz. The motors can be used in explosion hazards areas with certification conforming to IEC (ATEX, IEC Ex, INMETRO, TR CU or others on request) and NEC/CEC (CSA) for protection classes Ex nA or Ex pz/Ex px, as well as Class I Division 2.

Edited from press release by

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