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1. Before selecting the fan, should understand the domestic fan production and product quality, such as the production of fan varieties, specifications and a variety of products for special purposes, new product development and promotion, etc., should also take full account of environmental protection In order to choose the preferred fan.
2. According to the ventilator transport gas physical and chemical properties of different, choose different purposes of the fan. Such as the transport of explosives and flammable gases should be selected explosion-proof fan; dust or transport of coal should be selected dust or pulverized coal fan; corrosive gas should be transported to choose anti-corrosion fan; work at high temperatures or Conveying high temperature gas should be selected high temperature fan and so on.
3. In the fan selection performance chart to find more than two kinds of fans to choose from, should give priority to select the higher efficiency, smaller machine: a larger range of adjustment, of course, should be compared, trade-off The pros and cons of the decision.
4. If the selected fan impeller diameter is much larger than the original fan impeller diameter, in order to take advantage of the original motor shaft, bearings and bearings, etc., must be the motor start time, the original parts of the fan strength and the critical axis Speed ??and so on.
5. When selecting the centrifugal fan, when the motor power is less than or equal to 75KW, it can not be installed only for the start of the valve. When the high temperature flue gas or air and the choice of centrifugal boiler fan, the start should be used to prevent the cold valve caused by overload operation.
6. For ventilation systems with muffling requirements, first select the ventilator with high efficiency and impeller peripheral speed and make it work at the highest efficiency point. Also, according to the noise and vibration propagation mode of the ventilation system, Muffler and damping measures. Ventilator and motor vibration control measures, generally can be used vibration base, such as spring shock absorber or rubber shock absorber and so on.
7. When selecting a fan, try to avoid using the fan in parallel or in series. When the inevitable, should choose the same model, with the performance of the fan work together. When using the series, the first stage of the fan to the second stage between the fans should have a certain pipeline connection.
8. The selected new fan should consider making full use of the original equipment, suitable for on-site production and installation and safe operation and other issues.