Natural ventilation device, also called the roof ventilator and natural ventilation ball, is ventilation equipment put on the top sides of the industrial buildings. Without electricity supply, it brings enough outdoor fresh air in 24 hours, promoting the plant air circulation convection and improved working environment.
Common material on the market: color steel and stainless steel (201 and 201 stainless steel material). This product is oil and electricity free, no need to repair with simple installation. It only needs 3.2 km/h wind or more than three degrees Celsius temperature difference between indoor and outdoor conditions to ensure operating 24 hours a day. It can reach the goal of ventilation.
Function: Produce air convection, heat release, reduce air conditioning load and increase indoor fresh air. It can also drain moisture, mildew and steam humidity from the roof, keeping the proof dry. Compared with heavy electric blowers, it reduces support costs and noise and saves electricity.

Application: Applicable to all factories, warehouses, and the roof ventilation, aeration, air release spaces.

Working principle:

1. Using principle air convection in nature, flow any parallel direction air, speed up and shift to vertical air flow.

2. Using stack effect produced by the buildings and equipment combination to achieve indoor ventilation.

Natural ventilation device airflow parameter list:  air units: m3/hr

External wind speed Specification	0.5	1	1.5	2	2.5	3	3.5	4	4.5
Ф300	7	15	67	126	187	352	668	1683	2472
Ф450	34	131	334	423	600	833	1417	2834	3960
Ф500	39	151	384	486	690	1015	1630	3259	4554
Ф600	61	173	684	985	1397	1890	2457	3410	4946
Ф800	92	260	1026	1478	2096	2835	3686	5115	7419