GY4-68 centrifugal fan

G4-68 and Y4-68 centrifugal draft fans are a series of products jointly designed by the fan industry in 1982, suitable for use in steam boilers with a capacity of 230t/h or less in thermal power plants. Unless otherwise specified, G4-68 type can also be used for mine ventilation and general ventilation. Both types of fans have the advantages of high efficiency, low noise, and high strength. The medium conveyed by the ventilation fan is air, with a maximum temperature not exceeding 80 ℃. The medium conveyed by the induced draft fan is flue gas, and the maximum temperature shall not exceed 250 ℃. Before the induced draft fan, a dust removal device with a dust removal efficiency of not less than 85% must be installed to reduce the dust content of the flue gas entering the fan and improve the service life of the fan.
The ventilation fan and induced draft fan are both single suction air inlet, with seven machine numbers including No.8, No.9, No.10, No.11, No.11.2, No.12.5, No.14, and No.16. Each type of fan can be made into two types: right-handed and left-handed rotation. Looking at the fan from one end of the motor, if the impeller rotates clockwise, it is called a right cyclone fan, represented by "right"; if the impeller rotates counterclockwise, it is called a left cyclone fan, represented by "left". The outlet position of the fan is represented by the angle of the air outlet of the casing, and "right" and "left" fans can be made into six angles: 0 °, 45 °, 90 °, 135 °, 180 °, and 225 °.
The transmission mode of the fan is all D-type, and the motor and fan are connected by elastic couplings for direct transmission. These two types of fans are mainly composed of impellers, casings, air inlets, regulating valves, and transmission components.
Impeller: consisting of 12 aft sloping wing shaped blades welded to the center of an arc-shaped cover and a flat disc. The impeller of the induced draft fan adopts a solid body at the blade head, and wear-resistant materials are added to the easily worn parts for welding, which improves the service life of the blades. The impellers have undergone static and dynamic balance tests to ensure smooth operation.
Shell: The shell is a snail shaped body welded from ordinary steel plates. The casing of a single suction fan is made in two different forms: the casing of No. 8 to 12.5 is made into a whole structure. One quarter of the chassis of No. 14 and No. 16 can be removed. For the induced draft fan, there is a dust removal door above the snail shaped plate, and it is appropriately thickened to prevent ash wear and extend its service life.
Air inlet: It is a convergent streamlined overall structure, fixed on the inlet side of the casing with bolts.
Regulating door: a device used to adjust the flow rate of a fan. № 8~12.5 consists of 13 flower shaped blades, all installed axially in front of the air inlet. Due to the use of an external transmission structure, it rotates flexibly and conveniently. The adjustment range is from 90 ° (fully closed) to 0 ° (fully open). Adjust the lever position of the door, looking from the direction of the air inlet, on the right side. For the right cyclone machine, pushing the lever from bottom to top is the direction from fully closed to fully open. For the left cyclone machine, pulling the lever from top to bottom is the direction from fully closed to fully open. In order to ensure the normal operation of various parts of the regulating door, good lubrication is necessary. The regulating door of the ventilation fan is lubricated with calcium sodium based grease. For the induced draft fan, due to the high gas temperature, molybdenum sulfide high-temperature (260 ℃) lubricating grease is used to ensure lubrication during high-temperature operation.
Transmission group: The transmission mode is all D-type. Composed of spindle, bearing box, coupling, etc. The spindle is made of high-quality steel. Adopting a rolling bearing water-cooled integrated bearing box. Therefore, it is necessary to install water pipes, and the water consumption varies depending on the ambient temperature, generally considered at 0.5~1 m3/h The bearing box is equipped with a thermometer and an oil level indicator. The lubricating oil is made of No. 30 mechanical oil, and the amount of oil added is according to the requirements of the oil level mark.