A healthy, independent and reliable industrial chain is crucial to the development of wind power, in which self-research is the core foundation, manufacturing is the top priority, and ultimately leads to efficient and reliable delivery.
The level of understanding of the core components directly determines the improvement of the efficiency and safety of the entire wind turbine system. As a leader in the localization of wind turbines, Envision has been starting from basic research since 2009, insisting on doing the difficult but right thing, opening the black box of the design and manufacture of core components such as frequency converters, pitch systems, generators, blades, gearboxes, and main bearings, and continuously promoting a healthy balance between fan performance, reliability and cost.
After more than 30 years of development, China's wind power has entered a "no man's land", and there is not much experience to learn from in terms of technological innovation and product form. Envision uses national feelings to open up the "deep water area" of wind power technology, and represents the highest level of China's wind power in many fields and ranks among the world's first-class.
From simple system integration to gradually improving the localization rate of the whole machine, to self-developed and self-made core components, and vertical integration of the industrial chain, it has entered 3China's wind power industry in the 0 era has entered a "no man's land". This means that there is no precedent to follow, no experience to learn from, and we can only try and explore boldly.
As the "last mile" of wind turbine localization, the main bearing has long plagued China's wind power manufacturing industry, especially the large main bearing that matches the large megawatt wind turbine that has gradually become the mainstream, and there is also a lack of mass production experience in the world, let alone actual operation. Nowadays, Chinese wind companies are making history in the "no man's land" alone - Envision's self-developed and self-made main bearings have been delivered 4,600 units in 5 years, with zero failure in operation, forming a closed loop from design, manufacturing, testing and verification to reliable operation, which not only improves the performance and reliability of wind turbines to an unprecedented new height, but also more effectively promotes China's wind power chain to become a "cooperation chain" and "win-win chain", representing the highest level of China's manufacturing industry and ranking among the world's first echelon
Form a closed loop of the whole process
Realize the whole process management
The main bearing is a high-precision part, and the precision control requirements are as high as micron, which puts forward extremely high requirements for all aspects of design, manufacturing and quality management. Although the internationally renowned bearing brands that have long occupied China's wind power market have deep technical precipitation, there are also shortcomings: driven by profit targets, bearing products are unified and standardized as much as possible in order to reduce R&D and production costs, and are suitable for more markets and industries. Domestic bearing enterprises entered the wind power industry late, and also manufactured more general bearing products, and the understanding of the main bearing of wind power is not deep, and the product design matching the wind turbine is impossible to talk about.
How to start from the actual application conditions of the fan, customize the main bearing products, better realize the coordination with the fan control, and then create a main bearing that is fully suitable for the fan products and application scenarios, has become a difficult problem in front of the whole industry.
There is no other way than self-development and self-production.
However, it is no easy task to develop the main bearings in-house. Envision's self-developed bearing team said that in addition to matching the fan control and operation scenarios at the design source, the manufacturing of the main bearing also has high requirements for precision control, which not only requires advanced manufacturing equipment and high-standard materials, but also has to keep up with the related staffing and training, and also needs to achieve strict quality control of the whole process of batch product consistency. The ability to control the stability of mass manufacturing is the biggest test for bearing manufacturers.
Reliable main bearings are inseparable from the optimal design of the source, the test and verification of simulating the real working conditions of the fan, and the strict management of the manufacturing process. Five years ago, Envision set up a team that brings together top talents in various industries, formed a joint force with the first-class chain enterprises, and made simultaneous efforts in the three links of design source, manufacturing technology and quality control, and began to create the main bearing that is truly suitable for fan products and application scenarios.
Strictly control the quality
Stick to the source of innovation
Load carrying capacity is a key indicator of bearing performance, and high load carrying capacity main bearings make the wind turbine run longer life.
However, the final quality of the bearing is closely related to the basic raw materials and the underlying technology. For example, material fatigue can have a direct impact on the life of a main bearing. Only by removing the non-metallic inclusions to the greatest extent and strictly controlling the cleanliness of the steel can the occurrence of material fatigue be delayed.
It is precisely because of the great importance attached to the testing and control of the purity of raw materials that Envision has established its own bearing raw material standards and testing requirements, which are also the highest standards in the current industry.
In addition, in order to ensure that sufficient compressive stress is formed on the surface after heat treatment, we use new heat treatment technology to improve wear resistance while greatly delaying the propagation of local microcracks, so as to improve the overall bearing capacity and greatly improve the operating life of the bearing. Envision's self-developed bearing team said.
Due to the dynamic changes in the wind turbine load, the movement of the rollers can lead to slippage and wear during the operation of the main bearing, which is the origin of bearing spalling. In response to this phenomenon, Envision is the first in the world to apply the theory and technology of friction work to the field of wind power, effectively controlling the friction and wear caused by the load of the wind turbine, and significantly extending the life of the main bearing.
Theoretical and technical innovation is inseparable from rigorous testing and verification.
In the past few years, Envision has invested heavily in testing and verification: it has become the first wind turbine manufacturer in China to invest in a five-degree-of-freedom test platform, built the country's largest main bearing test bench with dynamic bending moment loading capacity, and has the only 20 MW transmission chain test bench in China that can achieve bending-torsion coupling.
China's largest wind turbine main bearing test bench with dynamic bending moment capability.
Envision's self-developed bearing team said that although some foreign brands of parts manufacturers also have their own test benches, most of them can only do the loading of static working conditions, while the actual working conditions of the wind turbine are changing rapidly, and the test platform that simulates the real working conditions to the greatest extent can better escort the quality of parts. In addition to the industry's conventional pure torque loading, the Envision test platform can also realize bending moment loading, torque and bending moment coupling loading, as well as shock load, alternating load and fluctuating load testing, which is as close as possible to the actual application conditions of wind turbines.
Envision's test benches can simulate the real input of the wind turbine. We have arranged hundreds of sensors in the main bearing and transmission chain, and have done very detailed attitude and force monitoring for the temperature, displacement, strain, deflection angle of the main bearing under fluctuating loads, especially for the rolling elements. From this monitoring data, we capture and build a theoretical model of friction and wear caused by external operating conditions. Envision's self-developed bearing team said.
Coupled with Envision's unique Galileo system to monitor the load and fatigue state of each wind turbine's main bearing, nearly 10,000 wind turbine data further revised the theoretical model obtained from the test bench. The more data is accumulated, the more accurate the model related to the reliability of the operation state of the batch wind turbine and the reliability of the bearing life, which is also the unique advantage of the whole machine manufacturer represented by Envision.
In the eyes of the industry, only wind turbine manufacturers can combine the basic characteristics of the bearing itself with the characteristics of wind turbine operation. Through bench test and wind farm operation data feedback, the load control of the wind turbine can also be realized according to the state of the bearing, which can improve the life of the bearing, and then improve the reliability of the whole system.
In the past five years, Envision has developed a total of 14 main bearing products, delivered more than 230 projects, and delivered a total of 4,600 units, with zero failure so far, which is a performance that has never been achieved by the world's top bearing manufacturers. Through the improvement of design, quality and cognition, the main bearing designed based on innovative concepts can help reduce the manufacturing and operating costs per kilowatt of wind turbines compared to the main bearings based on conventional cognitive design, especially in today's high operation and maintenance costs of offshore large megawatt wind turbines, the value creation of the main bearing reliability improvement is self-evident.
Empower parts manufacturers
Drive the whole industry chain
As the industry says, the slow localization process of the main bearing of the wind turbine is not a one-sided design, processing or quality management bottleneck, but each link is interlocking, and only by opening up all of them can we produce reliable and batch delivery products.
It is through years of experience accumulation that Envision has today's cognition, and has integrated this cognition into every link. For wind power developers, Envision provides complete machine products with better cost performance and higher reliabilityFor manufacturers of main bearings and other components, Envision empowers them with their deep understanding of the whole machine, systems and components, and helps them to manufacture main bearing products that are more suitable for the whole machine system and more suitable for actual operating conditions.
Envision's self-developed bearing team said: "We are the empowerment of the main bearing foundry in an all-round, whole-process and full-scale manufacturing system, not just in terms of process support or quality testing, in addition to its own design development and testing and verification activities, we are deeply involved in the equipment selection, production line layout, first-chain planning, process release, etc. With the improvement of delivery capabilities, in addition to the regular first-class business management activities, it also drives the digital and intelligent high-end manufacturing software and hardware configuration, accelerates the on-site automatic management and digital document management, and has efficient traceability capabilities, and then connects with Envision Smart Platform to achieve quality management throughout the life cycle. ”
Envision's management of the best business starts from the source, and there is a professional integrated development team responsible for the development, review, verification and release of the whole chain of steel, heat treatment, machining, assembly, factory inspection, etc., to ensure that the production factors and process control such as equipment, technology, and personnel can meet the requirements of high-quality delivery.
Although the 4,600 main bearings developed by Envision are all used in its own brand of wind turbines, in the process of cooperation with parts manufacturers, the latter can reuse its manufacturing and quality control capabilities in the whole field of manufacturing, which will drive the improvement of the level of China's wind turbine manufacturing industry chain as a whole.
It is precisely because the wind turbine manufacturers actively play the role of "chain master", actively empower the main bearing manufacturers, and then expand the overall delivery capacity of domestic manufacturers, in order to ultimately promote the competitiveness of the local wind turbine chain, and ensure the safety, stability and efficiency of China's wind turbine manufacturing industry chain.
At present, the localization ratio of main bearings in the wind power industry has increased from about 10% before 2021 to about 48%, and the average cost of self-developed main bearings has been reduced by more than 30% compared with foreign brands, which has strongly supported the high-quality development of the wind power industry and helped the wind power industry to pass through the cycle of low-price competition and become more competitive in the changes in the global chain pattern.
Text丨Zhuo Rui.