Fan selection is a highly technical work, the specific selection method is also many, such as: According to dimensionless characteristic curve selection, according to the logarithmic coordinate curve selection, according to a characteristic curve or performance table selection, Variant selection, according to pipe network resistance selection, there are still through the Web online selection system and the use of special selection software to selection. The method is complicated, and some methods need some professional knowledge. For general business people, familiar with and grasp of the performance table selection and fan selection software, two methods on it. These two methods are simple and easy to operate. Selection of fan, the first fan based on the required air volume, total pressure of these two basic parameters, you can through the fan with performance tables (each fan product manual has relevant data) to determine the fan model and machine number, which When more than one product may meet the requirements; then combined with fan use, process requirements, use occasions, select the type of fan, model and structure materials to meet the required working conditions, and strive to make the fan rated flow and rated pressure , As close to the flow and pressure requirements of the process, so that fan operating conditions point close to the high efficiency fan area characteristics. The specific principles are as follows: 1) In the choice of ventilator, you should understand the domestic fan production and product quality, such as the production of fan varieties, specifications and various products for special purposes, new product development and promotion, etc. Environmental protection should be fully considered in order to choose the best fan. 2) According to the different physical and chemical properties of ventilator conveying gas, select the ventilator for different purposes. Such as the transmission of explosive and flammable gas should be selected explosion-proof fan; dust or coal conveying dust should be selected or pulverized coal fan; conveying corrosive gases should choose anti-corrosion fan; work in high temperature or Transmission of high-temperature gas should be selected high-temperature ventilators. 3) In the fan performance chart to check there are more than two kinds of fan to choose from, you should give priority to select a higher efficiency, smaller number: a larger adjustment range, of course, should be compared to balance The pros and cons of the decision. 4) If the diameter of the selected fan impeller is larger than the diameter of the impeller of the original fan, in order to utilize the original motor shaft, bearings and bearings, etc., the starting time of the motor, the original strength of the fan and the critical Speed ​​and other accounting. This article comes from the fans should reach the official website, reproduced please indicate the source. 5) When choosing the centrifugal fan, when it is equipped with the motor power less than or equal to 75KW, not only for the installation of the valve. When the discharge of high temperature flue gas or air and select centrifugal boiler induced draft fan, should be set to start with the valve to prevent overload caused by cold operation. 6) Ventilation systems with muffling requirements should first select a fan with high efficiency and low circumferential speed of impeller, and make it work at the highest efficiency point. Correspondingly, according to the noise and vibration propagation mode produced by ventilation system, Noise reduction and vibration reduction measures. Fan and motor damping measures can generally be used to reduce vibration, such as spring shock absorber or rubber shock absorber. 7) In the choice of fan, fan should be avoided as far as possible in parallel or in series. When unavoidable, should choose the same model, the same performance of the fan work together. When using series, the first stage fan to the second stage fan should have some pipe connection. 8) The new fan should be selected to take full advantage of the original equipment for site production and installation and safe operation and other issues.