Breakthroughs in wind power bearing technology in recent years

2019-12-24

Wind power bearings are considered by the industry to be one of the two parts that are difficult to localize, and the other is the wind power control system. In recent years, China's wind power bearing industry has gradually formed large-scale and serialized production, the industry has been continuously expanded, key technologies have been continuously breakthrough, and a number of technologies and products with independent intellectual property rights have completed reliability tests.


■■ High-end bearings have become


Wind power equipment manufacturing weakness


Despite the rapid development of China's equipment manufacturing industry, most of the high-end bearings supporting major equipment rely on imports. In addition, large-scale wind turbine bearings, deep well drilling turret bearings, offshore drilling platform bearings and other high-end energy equipment bearings are also the weaknesses of domestic enterprises.


Industry experts believe that as one of the important supporting equipment for wind turbines, the stress and vibration of wind power bearings are complex, and they must withstand huge shock loads, and the installation costs of yaw and pitch bearings are relatively large. 20 years of life. Due to the harsh working conditions of wind power equipment and the requirements for long life and high reliability, wind power bearings have high technical complexity, which is one of the two major parts (bearings and control systems) that are difficult to localize.



Domestic wind power bearings rely on foreign imports for a long period of time, which is expensive, increases the cost of wind power equipment per kilowatt, and restricts the reduction of wind power costs. According to experts, the technical threshold for yaw bearings and pitch bearings in wind power bearings is relatively low, while the technical content of spindle bearings and gearbox bearings is relatively high. Generator bearings are basically universal products with mature technology. At present, the production capacity of domestic wind power bearing companies is mainly concentrated on yaw bearings and pitch bearings, and it is mainly supporting bearings for wind power equipment below 3 MW. For the main shaft bearings and gearbox bearings, they basically rely on imports, and only a few domestic companies Get involved.


■■ Low-speed wind power


New requirements for wind turbines


Whether the wind turbine is good or not, the bearing is the core factor. In the traditional wind turbine, the bearing plays the role of "Mr. Key". Because wind turbines are installed at high altitudes, the maintenance costs are high, and the working environment is harsh, and they are susceptible to pollution by sand, dust, water mist, and freezing. This requires that the supporting bearings must have high rigidity and reliability. Meet its 20-year service life requirements.



The test of bearings in the field of low-speed wind power is more severe. In recent years, China has vigorously developed the clean onshore wind power industry and transferred it to power load centers such as the southern Middle East. Due to the characteristics of low local average wind speed and rapid changes in wind speed and wind direction, new requirements have been imposed on wind turbines.



The central and southern regions of China are typical low wind speed regions, located in the center of electric load, and have good grid access conditions, but the average wind speed is low, the wind speed and wind direction change rapidly, and they have the characteristics of low energy density and high turbulence intensity. This requires the energy capture capability of wind turbines. In particular, in order to be able to withstand random alternating aerodynamic impacts, it is necessary to research and develop low-speed wind turbines and their supporting bearings in a targeted manner. There is no precedent in the world, and independent innovation is extremely difficult.



■■ Powered by independent innovation


National green and low-carbon development



Difficulties have not stopped domestic bearing companies from moving forward in exploration. As the first domestic enterprise to carry out the research and development of supporting bearings for wind power, Luoyang LYC Bearing Co., Ltd. (hereinafter referred to as "Luosha") has undergone more than 60 years of construction and development, and has become a comprehensive company with a large production scale and strong supporting service capabilities in China's bearing industry. One of the bearing manufacturing enterprises still maintains a number of Chinese bearing industry records such as high bearing production accuracy grades, complex structures, and large dimensions.



According to Zhang Wenbin, the person in charge of the marketing department of Luosha Company, Luosha successfully developed the first domestically produced fan yaw bearing in January 1997. It has been operating in the wind farm for more than 20 years and has become the Chinese bearing industry. Companies that have long been qualified in the field. In 2007, Luo Shao presided over the drafting of the national machinery industry standard-JB / T10705-2007 "Rolling Bearing Wind Turbine Bearings", and in 2012 he also wrote the national standard for fan bearings-GB / T29717-2013 "Rolling Bearing Wind Turbine Partial Aviation and pitch bearings ", GB / T29718-2013" Rolling bearing wind turbine main shaft bearings ".



In addition, Luoyang LYC Bearing Co., Ltd. as one of the main participating units of the "high-efficiency low-wind speed wind turbine key technology research and development and large-scale engineering application" project won the "2018 National Science and Technology Progress Second Prize" for the domestic bearing industry The national award project.



Lu Bingheng, an academician of the Chinese Academy of Engineering, believes that the research and development of high-end bearings involves a series of technical problems such as materials, grease and lubrication, manufacturing, design, bearing manufacturing equipment, testing and testing, as well as contact mechanics, lubrication theory, tribology, fatigue and damage, heat treatment and Basic research and interdisciplinary studies such as material organization. Must focus on industrial development policies, technology development planning and other aspects to solve the problem of lagging development of high-end bearings in the equipment manufacturing industry.