Selection and application of fan performance (I) Description of fan performance: 1. № 10, 12, 16, 20 are converted according to dimensionless performance of № 10 model. 2. № 5, 6, 8 are converted according to dimensionless performance of № 5 model. 3. № 5 and below shall be determined according to the performance of the measured prototype. Note: According to the dimensionless performance curve conversion formula, total pressure H=ρ u2 H (Pa) flow Q=900 π D22 uQ (m3/h) shaft power N=N × D22u3 ρ/4000 (kw), where D2 - impeller outer diameter (m) u - impeller outer edge linear speed (m/s) ρ - gas density (Kg/m3), the required power rate shall be based on shaft power plus mechanical loss and motor reserve. 4. The solid line is № 5 model, and the dotted line is № 10 model. The performance of the fan is expressed by the flow, total pressure, main shaft speed, shaft power, efficiency and other parameters of the fan, and there are certain relationships between the parameters, which are listed in the following table. The relationship of fan performance parameters changes density ρ, speed n changes speed n, atmospheric pressure P, gas temperature t Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 ρ 1/ρ 2 N1/N2=(n1/n2) 3 ρ 1/ρ 2 η 1=η 2 Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 (P1/P2) (273+t2/273+t1) N1/N2=(n1/n2) 3 (P1/P2) (273+t2/273+t1) η 1=η 2 Note: 1. In the middle, Q represents flow (m3/h), H represents total pressure (Pa), N represents shaft power (kw), η represents full pressure efficiency, ρ represents density (kg/m3), t represents temperature (℃), n represents speed (r/min), and P represents atmospheric pressure (Pa). 2. The footnote symbol 2 indicates the known performance and related parameters, and the footnote symbol 1 indicates the required performance and related parameters. （

Wuzhou major Boiler centrifugal fan WESP has the advantages of high dust removal efficiency, small pressure loss, simple operation, low energy consumption, no moving parts, no secondary dust, low maintenance costs, short production downtime, can work below the flue gas dew point temperature, can be combined with other flue gas treatment equipment due to its compact structure, and diversified design forms. The wet electrostatic precipitator uses liquid to wash the dust collector surface for dust removal, which can effectively collect fine particles (PM2.5 dust, SO3 acid mist, aerosol), heavy metals (Hg As、Se、Pb、Cr）、 Organic pollutants (PAHs, dioxins), etc. After the wet electrostatic precipitator is used, the smoke and dust emission in the wet flue gas can reach 10mg/m3 or even below 5mg/m3, and the dust collection performance has nothing to do with the dust characteristics, Boiler centrifugal fan manufactor It is suitable for the treatment of wet flue gas, especially for the treatment of dusty flue gas after wet desulfurization in power plants and steel plants. However, the equipment investment cost is high, and it needs to be used together with other dedusting equipment. Its investment, technical economy and operating cost should be evaluated from an overall perspective.

Wuzhou major Boiler centrifugal fan Installation requirements a. The foundation of the fan shall be level and solid, and the foundation height shall be ≥ 200mm. b、 The fan and air duct shall be connected by flexible hose (flexible material and non combustible), the length shall not be less than 200mm, and the pipe diameter shall be the same as the inlet and outlet size of the fan. In order to ensure that the hose will not be twisted or deformed during the system operation, it should be installed with appropriate tightness. The canvas hose installed at the suction end of the fan can be slightly tightened to prevent the fan from being sucked in during operation and reduce the sectional size of the canvas hose. c、 Boiler centrifugal fan manufactor The steel support of the fan must be fixed on the concrete foundation, and a rubber damping pad must be added between the steel support of the fan and the foundation. All fan and motor components are installed on the whole steel support, and the steel ground frame is installed on the damping pad at the top of the foundation. The damping pad is preferably made of perforated rubber plates. d、 The pipe diameter at the outlet of the fan can only be increased, but not decreased. At the end of the outlet, an insect screen should be installed. When the fan is inclined to the upper outlet, a rain cap should be added

major Boiler centrifugal fan The wet electrostatic precipitator mainly has two structural forms. One is to use corrosion-resistant conductive materials (which can be non-metallic materials with excellent conductivity or metal materials with corrosion-resistant characteristics) as the dust collector, and the other is to use non-conductive non-metallic materials as the dust collector by forming a conductive water film through water spray or overflow. Wet electrostatic precipitators can also be divided into cross flow type (horizontal) and vertical flow type (vertical) according to the flow direction of waste gas. The cross flow type is mostly plate structure, Wuzhou Boiler centrifugal fan The gas flows in and out in the horizontal direction, and the structure is similar to the dry electrostatic precipitator; The vertical flow type is mostly tubular structure, and the gas flow direction is vertical. Generally speaking, the efficiency of vertical flow wet electrostatic precipitator is twice as high as that of cross flow wet electrostatic precipitator under the condition of the same ventilation cross-sectional area. The dust deposited on the electrode plate can be washed down by water. Wet dust removal can avoid the re flying of captured dust and achieve high dust removal efficiency. Since there is no rapping device, the operation is also more reliable. The device that forms conductive film on the surface of the dust collector by means of water spray or overflow water has problems of corrosion, sludge and sewage treatment. It is only used when the dust concentration of the gas is low and the dust removal efficiency is required to be high; The wet electrostatic precipitator using corrosion-resistant conductive materials as dust collector does not need long-term water spraying or overflow water, Boiler centrifugal fan manufactor Regular flushing is only carried out according to the operating conditions of the system, and only a small amount of water is consumed. This part of water can be recycled, and the dust collection system is basically free of secondary pollution.

Wuzhou major Boiler centrifugal fan Fan performance parameters. The performance parameters of fan mainly include flow, pressure, power, efficiency and speed. In addition, the size of noise and vibration is also the main fan design index. Flow, also known as air volume, is expressed by the volume of gas flowing through the fan in unit time; Pressure, also known as wind pressure, refers to the pressure rise value of gas in the fan, including static pressure, dynamic pressure and total pressure; Power refers to the input power of the fan, namely shaft power. The ratio of effective power of fan to shaft power is called efficiency. Boiler centrifugal fan manufactor The total pressure efficiency of fan can reach 90%. Fans are widely used for ventilation, dust discharge and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings; Ventilation and induced draft of boiler and industrial furnace; Cooling and ventilation in air conditioning equipment and household appliances; Drying and selection of grain; Wind source of wind tunnel and inflation and propulsion of hovercraft. The working principle of the fan is basically the same as that of the turbine compressor, but because the gas flow rate is low and the pressure changes little, it is generally unnecessary to consider the change of gas specific volume, that is, treat the gas as an incompressible fluid

Preparations for fan installation. major Boiler centrifugal fan Before unpacking the fan, check whether the package is intact, whether the nameplate parameters of the fan meet the requirements, and whether all accompanying accessories are complete. Carefully check whether the fan is deformed or damaged during transportation, whether the fasteners are loose or fall off, and whether the impeller is scratched, and check all parts of the fan. Wuzhou Boiler centrifugal fan manufactor If any abnormality is found, it shall be repaired before use. Use a 500V megger to measure the insulation resistance between the fan housing and the motor winding. The value should be greater than 0.5 megohm. Otherwise, the motor winding should be dried. The temperature during drying should not exceed 120 ℃. Prepare various materials, tools and sites required for fan installation.