Keeping Cool. WEG’s New Water-Cooled Motors Take the Heat Off

When air-cooled motors aren’t enough, engineers start running out of options fast. With environments such as tunnel boring machines, ship engine rooms, and injection molding lines, these applications don’t exactly offer the luxury of vast open space or even clean airflow to the machines. Dust, humidity, and confined layouts make it difficult to keep traditional motors cool, which can cut efficiency and shorten service life.

That’s the problem WEG’s new W22 water-cooled motor line is built to handle. Instead of relying on external fans or ventilation ducts, the system circulates water through an internal jacket to draw heat directly from the motor. This approach allows for higher power density in smaller packages, prevents waste heat from being pushed back into the environment, and keeps performance steady even where air circulation is practically nonexistent.

WEG’s W22 water-cooled motors are ideal for tunnel boring, marine, and injection molding applications. Image (modified) used courtesy of WEG

Built for Environments Where Airflow Isn’t an Option

The W22 water-cooled motors remove the fan assembly entirely, eliminating one of the main sources of noise and mechanical wear. The motors feature cast-iron housing that includes smooth contours that prevent dust buildup, and the water jacket is fully sealed to resist contamination from particles or other types of debris that can be found in abrasive conditions, such as mining machinery or tunnel boring systems.

Because heat is removed directly through water circulation, the motor does not pass excess energy into the surrounding environment. This makes it particularly effective in areas where thermal control is critical, such as plastic injection molding, chemical processing operations, and even data centers.

Close-up cut out of the W22’s sealed water jacket, designed to maintain consistent cooling performance in harsh environments. Image (modified) used courtesy of WEG

Compact Power, Certified for Reliability

The W22 water-cooled line is capable of delivering outputs up to 450 kW, with frame sizes ranging from 324T to 506/7T and features configurations from two to six poles. Each unit operates at up to 460 V and 60 HZ, making it built to handle continuous duty under heavy loads. The system achieves protection ratings up to IP55, with insulation class options F or H.

WEG’s new motors are tested and certified to meet UL Listed, CE, and UKCA standards, giving them the approvals required for global installation. The cooling system follows the IC71W standard, which allows it to integrate easily into systems that already use water circuits for other processes. This makes it a strong fit for marine, textile, and wastewater applications.

WEG’s standard paint carries C4 protection against high corrosivity. Image (modified) used courtesy of WEG

Staying Cool in Harsh Conditions

Beyond tunnel boring and marine systems, WEG designed the new series of motors for compact installations and noise-sensitive environments. This includes machinery such as mixers, water treatment pumps, and textile spindles, where quiet operation and efficient heat management are just as important as raw horsepower. In facilities where airflow is restricted or temperature control is essential, switching to water cooling simplifies system design and extends motor lifespan.

In industries where heat is constant and space is scarce, WEG’s new W22 water-cooled series offers a straightforward way to increase performance without sacrificing reliability. By managing heat internally instead of fighting it externally, WEG has turned a long-standing challenge into an advantage for plants that never get a break from harsh conditions.