Advantages to be retarded fire exhaust fan ventilation: cooling effect is good; low energy consumption, is particularly important in promoting energy today; ventilation exhaust fan is easy to master the principles of opportunity, less prone to condensation; without a separate fan with a convenient and flexible . Due to the development of the machinery industry, to promote the country's economy also is in constant and rapid development, such as some machinery and equipment early years, the only exhaust fan installed from abroad, and now China has a strong technical and economic strength. Technology and manufacturing level exhaust fan the fire of the product with a very large increase exhaust fan manufacturers, constant research and development of new products to determine axial fan duct according to the exhaust fan air flow and wind speed (wind speed 10-15 m / s or so) cross-sectional area. Duct aspect ratio should not exceed 2: 1 (to save material and reduce the drag). Wind speed, wind pipe cross-sectional area, elbows, reducers, etc. to calculate the drag (ie fan static pressure required). Can not claim senior civil use of variable speed or multi-speed drive form, in order to achieve one machine (that usually use through ventilation and fire temperature exhaust) aims to use the exhaust fan, up Swiss machinery, Inner Mongolia smoke Fan ventilation and air conditioning provided by the liter Swiss mechanical and electrical equipment factory. L Rui HVAC Electrical Equipment Factory (www.dzsrxfkt.com) to provide "damper, fan coil motor" business, the company has "L Swiss" and other brands. Focus on the fan, ventilation equipment and other industries, have higher visibility in Dezhou. Welcomes inquiries, contact: province.