The structure and technical parameters of all commercially available galvanized square Exhaust fan are basically the same. The main models are 1380*1380*400mm1.1kw, 1220*1220*400mm0.75kw, 1060*1060*400mm0.55kw, 900*900*400mm0.37kw. The speed of all galvanized square Exhaust fan is 450 rpm, the motor is 4-pole 1400 rpm, the motor protection grade is IP44, and the B-class insulation. Individual smaller-sized Exhaust fan lose their significance as Exhaust fan due to small air volume, high noise, and low air extraction efficiency, and will not be described here. Relatively large Exhaust fan have higher ventilation efficiency and more energy saving.

FRP horn-shaped Exhaust fan are divided into two types: belt type and direct connection type according to the transmission structure. The belt-type speed is 370-450 rpm, and the six-pole or four-pole aluminum shell motor protection grade is IP55 F-class insulation, and the noise of the product with low speed is relatively low. There are mainly three types of direct motors: 12-pole 440 rpm, 10-pole 560 rpm, and 8-pole 720 rpm. 12-pole motors are used the most, and fans with high speed are noisy.

Belt-type products are the most energy-saving, economical and durable, and direct-connected products are suitable for use in places where belt-type products cannot work, such as oil pollution or corrosion to belts. FRP trumpet-shaped Exhaust fan blades mainly include 6 blades, 7 blades, 3 blades, and 5 blades. The blades are mainly made of die-casting aluminum alloy, engineering plastics (nylon plus fiber), and fiberglass. Fan blades with different number of blades, blade angle and radian need to be reasonably matched with the speed and power. A single data cannot explain the ventilation performance of the fan.