The coal mine fan is favored by the coal mine for its high pressure, large flow, high efficiency, compact structure and easy anti wind. The details are as follows: high transmission efficiency. The impeller is directly installed on the motor shaft, which changes the conservative transmission structure, not only avoids the frequent damage of the transmission device, eliminates the energy loss, and improves the transmission efficiency of the coal mine fan device. The pressure value of the highest pressure point of the coal mine fan is higher. The pressure is 1.2-1.3 times higher than that of the axial flow fan with back guide. High static pressure efficiency. Due to the counter rotating structure, the guide vane between the two working wheels is reduced, the internal resistance loss of the fan is reduced, and the static pressure efficiency of the coal mine fan is improved. High efficiency and wide range of efficient operation. The maximum efficiency of coal mine fan is about 8% higher than that of two-stage fan with front guide vane, and 4% - 5% higher than that of two-stage fan with rear stationary vane, so it has a wide range of efficient operation. The use of coal mine fan is flexible. Two working wheels of coal mine fan are driven by two motors respectively.
Therefore, the coal mine fan can carry out various combinations corresponding to different use conditions; the first stage idling can form a leading plus moving blade stage or a moving plus rear guide blade stage, and can also be equipped with a static blade as an accessory; the grid distance can be adjusted to achieve variable air volume regulation. The coal mine fan has a good reverse air supply performance (that is, the reverse air is easy), and the return air volume can reach 60% - 70% of the supply air volume. Because the coal mine fan can use the reverse air of the motor, neither the diffuser and diffusion tower, nor the fan room and the reverse air duct need to be built, the construction process is simple, so the construction period can be greatly shortened. Compared with other fans, it has less auxiliary equipment, less control links, good safety and reliability, and can save 70% of civil engineering cost. Blades and volutes are the components of coal mine fans that are easy to wear, and the fans used in power plants are the most serious. 1. Blade wear ① forward blade. In the pulverized coal system, the wearing parts of the blades of 7-29 type pulverized coal fan are mostly at the inlet, outlet and near the root of the rear disc.
