The principle of centrifugal cooling fan and its correct operation method
The centrifugal cooling fan is a machine that relies on the input mechanical energy to increase the gas pressure and discharge the gas. It is a driven fluid machine. Buy a centrifugal cooling fan, and find Tongchi automobile air conditioners, a professional manufacturer of centrifugal cooling fans. Centrifugal fans are widely used in grease factories, mainly including: ventilation and dust removal: used for oil cleaning, meal/hull crushing, ventilation and dust removal during oil/meal transportation; pneumatic conveying: such as wind transportation of soybean hulls and white soil Conveyor, air separation of skin/kernel, conveyance of coal ash; ventilation and drying: such as air induction of tempering tower, drying/cooling of puffed materials, drying/cooling of meal, etc. The structure of the centrifugal cooling fan: the centrifugal cooling fan is mainly composed of the impeller, the casing, the air inlet, the regulating damper and the driving device. Impeller: It consists of a front disc, a rear disc and blades installed between the two discs; Casing: The casing of the radiating fan is a volute shape and is welded with thin steel plates. Its function is to collect the gas from the impeller and make It is smoothly guided to the outlet of the cooling fan along the rotating direction of the impeller and pressurizes the gas. Air inlet: The head end of the suction pipe section plays a role of collecting air, so it is also called a collector. The working principle of the centrifugal cooling fan: When the impeller rotates with the rotating shaft, the gas between the blades also obtains inertial centrifugal force with the rotation of the impeller, and the gas is thrown out from the outlet between the blades. The thrown out gas squeezes into the casing, so the pressure of the gas in the casing increases, and is finally directed to the outlet to be discharged. After the gas is thrown out, the pressure in the center of the impeller drops. Outside air can be sucked in from the suction port of the radiator fan through the orifice in the center of the front disc of the impeller, and the gas is continuously delivered. The main performance parameters of the centrifugal cooling fan: flow Q: the amount of fluid delivered by the cooling fan per unit time, usually expressed in volume flow, in m3/s or m3/h, and related to the structure, size and speed of the cooling fan. Pressure head p: u200bu200bthe effective energy provided by the cooling fan to the unit volume flow, the unit is pa. Efficiency η: In the actual operation of the cooling fan, due to various energy losses, the actual (effective) pressure head and flow rate are lower than the theoretical value, and the input power is higher than the theoretical value. The parameter that reflects the magnitude of energy loss is called efficiency. The efficiency is related to factors such as the type, size, machining accuracy, gas flow and properties of the cooling fan. Generally, the efficiency of a small cooling fan is 50% to 70%, and a large cooling fan can reach 90%. Shaft power N and effective power Ne: Shaft power is the power input to the cooling fan shaft of the motor in W or kW. The effective power of a centrifugal cooling fan refers to the energy obtained by the gas from the impeller in a unit time, and Neu003dQp, Nu003dNe/ηu003d Qp/η. Rotation speed n: The number of revolutions per minute of the cooling fan and the cooling fan impeller is 'r/min'. Correct use and operation methods: 1. Preparations before starting the cooling fan. 1) Close the adjusting air door and close the air inlet and outlet doors of the cooling fan; 2) Manually crank, check the gap between the parts of the cooling fan, rotate the impeller and the casing to see if There is friction; 3) The coupling and pulley protection passport are installed in place; 4) Whether the oil level of the bearing box meets the lubricating oil level during operation; 5) For the cooling fan with water-cooled bearings, check the water supply of the cooling water pipe Good; 6) Determine the steering of the cooling fan by electric, and check for water and oil leakage, vibration, abnormal noise, and odor. 2. Start of the cooling fan 1) Start the cooling fan (pay attention to whether the operation is stable); 2) After the cooling fan is started, gradually open the large damper until the actual air volume required for production; when opening the large damper, pay attention to the running current of the motor to prevent the opening of the damper Excessive size will cause the cooling fan to be overloaded; 3) Check the bearing temperature of the cooling fan after starting, and the temperature rise of the bearing should not exceed 40 degrees of the ambient temperature on site. 3. Check the cooling fan during operation 1) Listen to whether the cooling fan is running smoothly, whether there is abnormal noise or friction; 2) Check whether the anchor bolts are loose; 3) Check the temperature and lubrication of the bearing; 4) Bearing lubrication Whether the oil cooling water is unblocked, and whether there is a temperature difference between the inlet and outlet pipes; 5) Whether there is lubricating oil leakage in the bearing box; 6) Whether the bearing box and bearing are running abnormally, and whether the rotation is stable; 7) Check whether the current operation is stable. 4. Emergency stop 1) A violent noise from the cooling fan is detected; 2) There is friction between the impeller and the casing; 3) The casing vibration suddenly increases; 4) The bearing temperature continues to rise and exceeds the allowable temperature rise range; 5) The current suddenly rises High and cannot be restored within 2 minutes; 6) The bearing box is seriously leaking; 7) The cooling water is interrupted for more than half an hour. 5. Stop the cooling fan 1) Now stop the cooling fan operation after reducing the load; 2) Close the cooling water inlet and outlet valves; 3) If the hot air is being delivered, the temperature of the cooling fan outlet should be reduced to 40 degrees after the heater is stopped. Stop the cooling fan at any time; 4) After the cooling fan is stopped, open the drain valve at the bottom of the casing for drainage; at the same time, close the inlet and outlet air doors of the cooling fan. Tongchi Automotive Air Conditioner is a professional cooling fan manufacturer integrating Ru0026D, marketing and after-sales service. Since Tongchi entered the field of cooling fans, it has always insisted on cooperating with aviation research units, combining aviation technology and cooling fan technology, and established the company's characteristics as a technology-based enterprise. Tongchi has always insisted on integrating the essence of Chinese and foreign cooling fan equipment, independently developed the 'Tongchi' brand, and has become a cooling fan manufacturer with complete product specifications, strong production strength and full of potential. It is an important production base for domestic cooling fans and provides national services. hotline:.