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.
major Centrifugal fan The reasons for failure caused by unstable operation are: improper temperature control of insulator box; The gas distributor grid is blocked, and the sediment electrode has too thick scale; Improper adjustment of water film; The oxygen content in the system exceeds the standard. ① Insufficient steam pressure and blocked steam pipeline may cause low temperature of insulator box. In the long run, the insulator surface temperature is low, and tar and dust particles accumulate, causing electric field short circuit. If the temperature of insulator box rises too fast, or the temperature changes violently during operation, the insulator will be cracked. ② Centrifugal fan company If intermittent flushing cannot be carried out as required during operation, the tar accumulated on the sediment pipe wall is difficult to be thoroughly cleaned, which, accumulated over time, not only causes excessive resistance to equipment operation, but also leads to damage to the electric field. ③ During maintenance, the water film is not adjusted as required, the water film is uneven or not thick enough, and after putting into operation, the phenomenon described in fault (4) will occur. The above situation also occurs when the water film is damaged during operation. ④ The reason for the explosion of the electrostatic precipitator is that the oxygen content in the gas exceeds the standard, the mixed explosive gas is formed in the equipment and reaches the explosion limit, and the explosion occurs when encountering electric sparks.
Preparations for fan installation. major 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. Chongzuo Centrifugal fan company 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.
major 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, Chongzuo 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, Centrifugal fan company 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.
(3) The main faults and causes of the fan may occur during the operation of the fan. For the faults generated, the causes must be quickly identified and solved in time to prevent accidents. Faults in the Operation of 4-72-12 Centrifugal Fan and the Causes Table Fault Name Causes Severe Vibration of Bearing Box 1. The fan shaft is different from the motor shaft, and the coupling is installed askew. 2. The casing or air inlet rubs with the impeller. 3. The foundation stiffness is not enough or firm. 4. Impeller rivet is loose or wheel disc is deformed. 5. The impeller shaft disk and shaft are loose, and the coupling bolt is movable. 6. The connection between casing and bracket, bearing box and bracket, bearing box and seat is loose. 7. The air inlet and outlet pipes of the fan are poorly installed, causing vibration. 8. The rotor is unbalanced. Bearing temperature rise is too high 1. The bearing box vibrates violently. 2. The lubricating grease is poor in quality, deteriorated or overfilled, or contains dust, sand, dirt and other impurities. 3. The tightening force of connecting bolts of bearing cover seat is too large or too small. 4. The shaft and rolling bearing are installed askew, and the front and rear bearings are not concentric. 5. The rolling bearing is damaged. The motor current is too high and the temperature rise is too high. 1. The throttle valve in the air inlet pipe is not closed tightly when driving. 2. The flow exceeds the specified value, or the air duct leaks. 3. The gas density conveyed by the fan is too high. 4. The input voltage of the motor is too low or the power supply is cut off individually. 5. The coupling is improperly connected, the leather ring is too tight or the gap is uneven. 6. Affected by the violent vibration of the bearing box. 7. Affected by deterioration or failure of parallel fans. When the belt slides down, the two pulleys are not in the same plane with each other. Belt runout The distance between two pulleys is too close or the belt is too long.
The wet electrostatic precipitator is a new kind of dust removal equipment used to treat micro dust and micro particles, major Centrifugal fan It is mainly used to remove dust, acid mist, water droplets, aerosols, odor, PM2.5 and other harmful substances in humid gases, and is an ideal equipment for controlling atmospheric dust pollution. The wet electrostatic precipitator is usually referred to as WESP, which has the same basic principle as the dry electrostatic precipitator. It goes through three stages: charging, collection and dust removal. The principle of wet electrostatic precipitator is the same as that of dry electrostatic precipitator, Chongzuo Centrifugal fan The dust is charged by high-voltage corona discharge, and the charged dust reaches the dust collecting plate/tube under the action of electric field force. The dry electrostatic precipitator mainly deals with dry gas with very low water content, while the wet electrostatic precipitator mainly deals with wet gas with high water content or even saturation. There is a big difference between WESP and DESP in the way of removing the dust collected on the dust collecting plate/pipe. The dry electrostatic precipitator generally uses mechanical rapping or acoustic cleaning to remove the dust on the electrode, while the wet electrostatic precipitator uses regular flushing to remove the dust along with the flow of flushing fluid