Dezhou Plumper ventilation plant is specialized in the production of central air-conditioning equipment manufacturers supporting the end. Products in full accordance with the national standard, standard production line damper models, advanced equipment and fire dampers, technical stability of the cross-sectional axial fans generally airfoil. Blades may be fixed position, and to be rotating about its longitudinal axis. Blades and the blade pitch angle or the air flow may be adjustable or not adjustable. Changing the blade angle or pitch is one of the main advantages of axial fan. Small blade pitch angles produce lower flow rate, while increasing the spacing may produce a higher flow rate. Six proportional to the total noise level of the fan blade speed. According to the analysis of 70 degrees dampers, fan noise source is basically a dipole nature. Further to be launched, the noise is due to the blades on the fan effect on air flow through the veins caused power. Fans may think there are two discrete frequency noise source, a field with the pressure caused by the movement of the rotor blade propeller noise, and the other is powered leaf veins aerodynamic noise caused by interference. Wind maneuver, quiet distance between the blades is an important factor interference noise. Automatic fire dampers, ventilation equipment Plumper (certified), fire dampers are provided by Shandong Dezhou Plumper ventilation plant. Dezhou Plumper ventilation plant (www.frtfsb.com) is a leader in Dezhou, fans, ventilation equipment, over the years, the company implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Rich ventilation equipment in leadership with the staff warmly welcome all inquiries negotiations to create rich, ventilation a better future.