The development of high-efficiency products is the key to energy-saving fans. Relevant statistics show that the electricity consumption of fan products in use in the country accounts for about 10% of the total power generation in the country. Among them, the electricity consumption of fans used in metal mines accounts for 30% of the total electricity consumption of mining in the country; the electricity consumption of fans used in the iron and steel industry accounts for 20% of the total electricity consumption of its production; and the electricity consumption of fans used in the coal industry accounts for 17% of the total electricity consumption of the coal industry in the country. Therefore, for the fan industry, how to produce more energy-saving and environmentally friendly fan products is an issue that requires great attention. Industry insiders believe that energy conservation and environmental protection are the eternal themes of the development of the fan industry. So, where should the fan manufacturer start?

Relevant experts believe that the research and development of energy-saving fan products should not only start from the product design, but also from the operation of the fan.

First of all, in the design, through the application of impeller, volute and other components of scientific research results, and further improve the manufacturing accuracy, and strive to make a variety of fan efficiency increased by an average of 5% to 10%. At present, the most advanced centrifugal fan due to the use of ternary flow impeller, its maximum efficiency can reach more than 87%; high efficiency of axial flow fan, its maximum efficiency has reached 92%.

For example, the 4-71 and 4-74 ternary flow impeller centrifugal fans successfully developed by Shenyang Blower Research Institute in 1992 for the upgrading of medium and low pressure centrifugal fans are new products with high efficiency and energy saving. Their efficiency is 4% higher than that of the same type of old fans, and the average annual power saving of each fan is about 2000 kW per hour. However, because the manufacturing process of the ternary flow blade used by the fan is more troublesome, the manufacturing cost is higher than that of the ordinary blade fan, and the technology transfer fee of the product is high, the manufacturing cost of the whole fan is increased, the user can not afford it, and it can not be fully promoted in the whole industry.

Secondly, the introduction of technology to develop energy efficient fan. For example, Shanghai Blower Factory Co., Ltd. and Shenyang Blower (Group) Co., Ltd. have introduced the moving blade adjustable axial fan technology of German TLT and Danish Nuo Wenke Company respectively; Chengdu Electric Power Machinery Factory and Shenyang Blower (Group) Co., Ltd. have introduced the static blade adjustable axial fan technology of German KKK Company; Wuhan Blower Co., Ltd. has introduced the moving blade adjustable axial fan technology of Mitsubishi Heavy Industries; guangzhou Fan Factory has introduced the axial flow and centrifugal fan technology of Denmark Nordisk Ventilation Equipment Company. Chongqing General Motors (Group) Co., Ltd. and Siping Jinfeng Co., Ltd. have introduced the high temperature fan technology of Britain's Hauteng Company. Shijiazhuang Fan Factory Co., Ltd. has introduced the centrifugal fan manufacturing technology of Japan's Ebara Company. Through the introduction of technology, it has effectively promoted the development of energy-saving ventilator products. During the "Eleventh Five-Year Plan" period, it is also necessary to appropriately introduce wind turbine technology and special-purpose fans according to market demand to fill the domestic gap.

In addition, whether the fan product is energy-saving or not, it is very important to adjust the speed change mechanism and change the operating conditions. At present, most of the fan speed change mechanism is relatively backward, individual products using the traditional triangle belt, worm gear pair, etc. as the speed control device, most of the use of regulating door adjustment. For the above reasons, although some fans have high internal efficiency (up to 86% or more), their device efficiency is not very high, and some even as low as 30%. With the application of hydraulic couplers and frequency converters in fans, the operating efficiency of fans has been greatly improved, but the number of applications is extremely limited.

At the same time, the "Eleventh Five-Year Plan" period should also vigorously carry out the development of energy-saving blowers, in this regard, foreign countries have been in the front. For example, Japan has made appropriate improvements to the shape of the flow passage parts such as volute and impeller, effectively preventing the generation of vortex and flow separation, and its thermal insulation efficiency is 5% ~ 10% higher than that of the original centrifugal blower. The large flow centrifugal blower made in Switzerland is equipped with an imported guide vane device at each stage, and its variable efficiency reaches 82%. The multi-stage centrifugal blower made in Japan adopts the continuous automatic adjustment of imported guide vanes, the energy saving rate is 20%; after the high-speed single-stage centrifugal blower adopts a high-speed, high-pressure ratio semi-open radial ternary impeller, its efficiency can be increased by 10%; and some are equipped with an exhaust turbine device at the other end of the blower main shaft, It not only meets the requirements of environmental protection, but also achieves the purpose of energy saving. Roots blower has adopted three-leaf Roots blower, which not only saves energy but also reduces noise.

In the development of centrifugal compressors, more ternary flow impellers should be used to increase the efficiency of the impeller by an average of 2% to 5%. For example, the three large-flow ternary flow impellers developed by the United States for natural gas pipeline transportation centrifugal compressors have impeller efficiency of 94% ~ 95%. The efficiency level of Japan's single-shaft multistage centrifugal compressor has also been further improved, and the adiabatic efficiency of its first-stage large-flow semi-open ternary impeller has reached 94%. The adjustment method should be more industrial steam turbine or gas turbine drive to change the speed to achieve the purpose of energy saving.