The fan is allowed to start at full voltage or at reduced voltage, but it should be noted that the current at full voltage starting is about 5~7 times the rated current, and the reduced voltage starting torque is proportional to the square of the current. When the grid capacity is insufficient, the reduced voltage starting should be used. (When the power is greater than 11KW, it is advisable to adopt the step-down starting.) When the fan is in test run, Axial flow fan Price Carefully read the product manual and check whether the wiring method is consistent with the wiring diagram; Carefully check whether the working voltage of the power supply to the fan meets the requirements, whether the power supply is out of phase or in phase, and whether the capacity of the electrical components provided meets the requirements. During commissioning, the number of people shall not be less than two. One person shall control the power supply and the other person shall observe the operation of the fan. If any abnormality is found, stop the machine immediately for inspection; First, check whether the rotation direction is correct; After the fan starts to run, immediately check whether the running current is balanced and whether the current exceeds the rated current; major Axial flow fan If there is no normal phenomenon, stop the machine for inspection. After five minutes of operation, stop the machine to check whether the fan is abnormal, and start the machine again after confirming that there is no abnormal phenomenon. When the two speed fan is tested, start the low speed fan first and check whether the rotation direction is correct; When starting the high-speed train, the fan must be stopped before starting to prevent the switch tripping and motor damage caused by high-speed reverse rotation. When the fan reaches the normal speed, check whether the input current of the fan is normal, and the operating current of the fan cannot exceed its rated current. If the operating current exceeds its rated current, check whether the voltage supplied to the fan is normal. The motor power required by the fan refers to the higher power required for centrifugal fan and fan box when the air inlet is fully open under certain working conditions. If the air inlet is fully opened for operation, the motor may be damaged. During fan commissioning, it is better to close the valve on the inlet or outlet pipeline of the fan, open the valve gradually after operation until the required working condition is reached, and pay attention to whether the operating current of the fan exceeds the rated current

Axial flow fan Price The work starts before the fan is used. one Qiandongnan Axial flow fan Price Carefully read the fan operation instructions and product samples, and be familiar with and understand the fan specifications, forms, impeller rotation direction and air flow in and out direction; Check whether all parts of the fan are in good condition again, or they can be installed and used only after being repaired. 2. The fan must be installed with safety devices to prevent accidents, and installed and wired by professionals familiar with relevant safety requirements. 3. The air duct connecting the inlet and outlet of the fan has separate support, and it is not allowed to add the overlapping weight of the duct to the components of the fan; When installing the fan, pay attention to the horizontal position of the fan, and adjust the connection between the joint surface of the fan and the foundation and the air outlet pipe to make it coincide naturally. Forced connection is not allowed. four major Axial flow fan After the fan is installed, move the impeller by hand or lever to check whether it is too tight or rubbed, and whether there is any object that hinders the rotation. The test run can be carried out only when there is no abnormal phenomenon. The exposed part of the fan transmission device should be equipped with a protective cover (provided by the user). If the fan inlet is not connected, a protective screen or other installation device (provided by the user) should also be added. 5. The power distribution control box of the fan must match the corresponding fan (power, voltage, pneumatic mode, control mode, etc.). 6. The fan wiring should be made by a professional electrician, and the wiring must be correct and reliable. Especially, the wiring number at the electric control box should be consistent with the number on the fan terminal. The fan shell should be reliably grounded. The grounding must be reliable, and zero connection cannot be used instead of grounding. 7. After all fans are installed, check whether there are any left tool box sundries inside the fan

major Axial flow fan Common fault: the working medium of the fan in the cement industry often contains a certain amount of homogeneous particles with different sizes and shapes, such as the induced draft fan of the dust removal system and the blower for pneumatic conveying. Because these fans work in the dusty air flow, the dust particles in the air flow will not only wear the fan, but also attach ash on the fan blades, and the wear and ash deposition are uneven. As a result, the balance of the fan rotor is destroyed, which causes the fan vibration and shortens the life of the fan. In serious cases, the fan can not work normally. Especially, the fan blades are worn most seriously, Axial flow fan Price It not only destroys the flow characteristics in the fan, but also easily leads to major accidents such as blade fracture and runaway. The wear of transmission parts is also a common problem of fans, including various shafts, rollers, reducers, motors, pumps and other bearing positions, bearing seats, keyways, threads and other parts. The traditional repair welding machine processing method is easy to cause material damage, resulting in deformation or fracture of parts, with greater limitations; Brush plating and spray re machining methods often require outsourcing, which not only requires long repair cycle and high cost, but also can not fundamentally solve the causes of wear (poor impact resistance and yield of metal) because the repair materials are metal materials; Many parts can only be scrapped and replaced, which greatly increases the production cost and inventory of spare parts, leaving the enterprise's good resource advantage idle and wasted

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.

（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.