Equipment for ventilation type "snail" is provided by electric motors with explosion-proof lids and housings. For the coloring of engine cases, a special protective structure is used.
Most of these are asynchronous mechanisms with fixed speeds. They connect to a single-phase or three-phase network, depending on the design. In special cases, engines with adjustable speed of rotation are used.

Dimensions The sizes of "snail" hoods can be different. The diameter of the unit varies from 250 to 1500 mm. "Snail" can be a single whole or be divided into several parts. In the case of small ventilators with a single snail, the angle of rotation can be neglected.

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