In principle, the negative pressure fan is designed by using the principle of air convection and negative pressure air exchange. The negative pressure fan is installed in the place where the ventilation is poor. when working normally, the mechanical kinetic energy is used to make the fan run, and the stagnant hot air, odor and black smoke of the factory building are quickly discharged outside in a short period of time, and the fresh outdoor air and indoor air are recycled and exchanged at the same time, so as to achieve the purpose of ventilation and cooling to improve the environment of the workshop. The high temperature, muggy, smoke, dust and odor gas in the workshop are all discharged outdoors, so we can see that the negative pressure fan is also a smoke exhaust fan! 

In terms of exhaust air volume, the specification of smoke exhaust fan is in accordance with the provisions of the Code for Fire Protection Design of High-rise Civil buildings. The small air volume of the smoke exhaust fan is 7200m/h, and the large air volume should not exceed 60000m/h. It is enough to see that the negative pressure fan can also be used as a smoke exhaust fan. 

In terms of the use effect, the negative pressure fan is installed in the environment of poor ventilation such as high temperature, muggy heat and smoke, which requires a change of air every minute, thus it can be seen that the smoke exhaust effect is all good! In terms of operating costs, the power of the negative pressure fan is between 0.37 and 1.1KW. As a smoke exhaust fan, the negative pressure fan with such a small power and large exhaust air volume saves a lot of cost. Of course, I would also like to tell you that the negative pressure fan can only be used as a simple smoke exhaust fan, can not be used in machinery and equipment and high requirements of smoke exhaust.