9. Since the flow, total pressure, main shaft speed and shaft power of the fan have a fixed relationship, the main shaft speed should not be changed when the motor capacity does not change. If the main shaft speed increases, the motor may be burned due to overload. The motor power used by the fan refers to the power not required when the air inlet and outlet are fully open in terms of mechanical losses and due reserves under a specific mine. If the outlet or inlet of the fan is not connected to the pipeline or is idle without external resistance, the motor may also be burned out. For safety, a valve shall be added to the outlet or inlet pipeline of the fan, and it shall be closed when starting the motor. After turning, the valve shall be slowly opened until the specified working condition is reached, and attention shall be paid to whether the current of the motor exceeds the specified value. High power motors must be started in proper ways, such as voltage reduction, frequency conversion, etc.
Foshan major Wet electrostatic precipitator 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、 Wet electrostatic precipitator Price 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
2. The influence of the total pressure deviation Δ H of the fan itself was not considered during selection. When the actual total pressure of the fan was positive deviation, the flow increased; When the actual total pressure of the fan is negative deviation, the flow decreases. See (a) below. The relationship between the deviation of the pipe network characteristic curve and the total pressure and the flow can be eliminated by one of the following methods when the fan starts to officially operate after new installation, or when the flow is too large or too small during use. 1. Use the opening and closing of throttling device to adjust the flow. 2. Increase or decrease the flow by increasing or decreasing the fan speed. 3. Use a new fan with higher or lower pressure to increase or decrease the flow. 4. Change the pipe network to reduce the resistance coefficient of the pipe network to increase the flow. It must be pointed out that throttling devices are generally used to regulate the flow. However, when the actual flow is much larger than the required flow, this method wastes too much power and is very uneconomical. If conditions permit, the fan speed is usually reduced or the fan with lower pressure is replaced. When the throttling device is fully open, the flow is still too small. At this time, the throttling device has lost its function, so try to reduce the resistance coefficient of the pipe network to increase the flow, or increase the fan speed and replace the fan with higher pressure. However, the speed of the fans directly connected to the motor and the coupling cannot be changed generally. Only the fan driven by the pulley can increase or decrease the speed by changing the diameter of the pulley, but the speed of the fan cannot exceed the speed max in the performance and selection table.
Foshan major Wet electrostatic precipitator 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. Wet electrostatic precipitator Price 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