How long will it take for the localization of wind power spindle bearings?
　　With the increase of investment of domestic enterprises and the improvement of technology, in the next three to five years, domestic spindle bearings are expected to keep pace with foreign brands, and achieve a wider range of domestic substitution in the near future.
　　As the core component of the wind turbine, the main shaft bearing has complex and changeable loads, high reliability and precision requirements, and its design life needs to reach more than 25 years. Due to the high technical difficulty, foreign brands have long occupied most of the domestic market share with the accumulation of technology and experience. In recent years, with the improvement of domestic enterprises in scientific research, technology, craftsmanship, etc., coupled with the impact of the epidemic and cost pressure, domestic wind power spindle bearings are expected to keep pace with foreign brands within three to five years, and will be realized in the near future. A wider range of localized substitution.
　　The localization rate of spindle bearings is increasing year by year
　　The installed scale of wind power in my country has been on the rise for many years, so the demand for spindle bearings has increased rapidly. Due to the high requirements on life and reliability of wind turbine spindle bearings, for a long time, three foreign companies, Schaeffler, SKF and NTN, have occupied most of the domestic market share, while the spindle bearings used in offshore wind turbines are almost monopolized by foreign brands.
　　"In the past three years, the market share of foreign brands (onshore wind power) has gradually dropped to about 65% due to the substitution of localization. The gap between domestic spindle bearings and foreign products is narrowing from design to manufacturing. Major domestic bearing manufacturers, the 3~6.25MW main shaft bearings used in mainstream models have been installed and used in large quantities, and the main shaft bearings of offshore wind turbines below 10MW have also entered the stage of research and development and prototype trial. It is estimated that in 2022, the main shaft bearings (onshore) The conversion rate can be increased to 40%. As the bidding price of the main engine has dropped significantly, the OEMs are paying more attention to the cost of bearings and other components, and the localization of spindle bearings has become the general trend. Domestic spindle bearings are the premise of ensuring product quality. The lower price advantage is more obvious. In the next three years, it is inevitable that the market share of domestic spindle bearings will exceed that of imported bearings." Yu Haibo, general manager of Luoyang LYC Bearing Co., Ltd. (hereinafter referred to as "Luozhou"), told "Wind Energy".
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　　The difficulty of developing large megawatt spindle bearings increases
　　Spindle bearings are the most expensive bearings in wind turbines with high technical barriers. The rapid development of wind turbines in the direction of large-scale has brought many challenges to the localization of high-tech spindle bearings. It seems to be just an enlargement of the size, but the difficulty increases geometrically. Large size means higher load, plus high speed and long running time, all of which require a comprehensive upgrade of design, materials, cold and heat treatment processes, inspections, tests, etc., as well as more requirements for production equipment and testing equipment. demanding requirements.
　　There are three types of common spindle bearings: spherical roller bearings (SRB), tapered roller bearings (TRB), and three-row cylindrical roller bearings (CRB). Spherical roller bearings are mostly used for doubly-fed, 5MW or less models, and their advantage is that they have relatively strong resistance to deflection. Direct drive and semi-direct drive models mostly use tapered roller bearings and three-row cylindrical roller bearings, which are suitable for units with larger single capacity. At present, tapered roller bearings are the focus of research and development of domestic enterprises.
　　Design is the key link in the development of spindle bearings. In addition to the wind load, the main shaft bearing also bears the gravity load of the main shaft and the impeller, and the working conditions are complicated. In the design, the bearing is required to have good impact resistance, flexible centering performance, and excellent raceway fatigue resistance. According to Wang Yi, a bearing strategic purchaser of Shanghai Electric Wind Power Group Co., Ltd., some highly capable complete machine chambers of commerce will hire experts to design and hand over the design drawings to the bearing factory for production. If there is no professional ability in this area, the supplier needs to have the corresponding design ability or entrust a third party to design.
　　The difficulty of materials mainly lies in the fatigue life, which is related to the type, size and distribution of non-metallic inclusions in the raw materials. Among them, brittle inclusions and large-grained inclusions have the greatest impact on the life. Therefore, how to further improve the cleanliness of bearing steel, reduce the content and size of inclusions in the steel, and improve the uniformity of carbides has become the focus. In addition, the hardness, strength and core toughness of the spindle bearing are closely related to the material selection. In order to improve the hardness of parts and ensure that the hardness of the core surface is consistent, the material is required to have good hardenability, hardenability and process adaptability. At present, carburized steel, high hardenability steel and medium carbon alloy steel are mostly used for large megawatt wind power spindle bearings.
　　Industry experts said that in terms of bearing steel materials, foreign brands have cultivated domestic suppliers in recent years, and their technological level and smelting level have improved greatly. The purity and chemical composition of materials can be comparable to those of foreign companies, but there is still a gap. "The raw materials for the spindle bearings of foreign companies are also purchased from domestic suppliers. The suppliers are forged according to the customer's bar material. The steel used for the bearings is marked with a number plate, and the ratio of its metal content is one of their core secrets." An industry insider revealed to "Wind Energy".
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　　In terms of technology, domestic enterprises basically have no difficulties in the development and production of wind power spindle bearings below 5MW. However, the manufacturing process of larger megawatt spindle bearings has increased a lot, such as cold working dimensional accuracy, heat treatment deformation, rolling element modification, raceway crown, material internal structure control, better surface treatment technology, including how to solve boundary friction And the lubrication problem after the intervention of external pollutants. In addition, processing larger-sized bearings requires larger and more precise processing and testing equipment, and the equipment itself is expensive.
　　The advancement of domestic spindle bearing technology has also been affirmed by foreign companies. Schaeffler said in an interview reply to "Wind Energy" that with the accumulation of experience in the application of spherical roller bearings, domestic bearings can already provide solutions with imported brands for customer projects. And with the improvement of the technical level and smelting level of bearing steel materials, the application and promotion of induction hardening heat treatment, and the increase in investment in production, the development of domestic brands is very fast, and the experience and production capacity are reserved for subsequent project development.
　　Where is the gap with foreign brands?
　　The development history of foreign bearing brands such as Schaeffler, Timken, SKF and NSK is much longer than that of domestic enterprises, and some even have a history of hundreds of years, with strong technical background and rich experience. On the other hand, domestic enterprises have only begun to conquer wind power bearings after the country introduced the policy of "over 70% localization rate of wind power equipment" in 2006. The research and development of main shaft bearings has only taken more than ten years.
　　Relevant persons in charge of several domestic large bearing factories said that for large megawatt spindle bearings, there is no "bottleneck" from the perspective of research and development, and the main lack is the accumulation of experience. In this regard, "Wind Energy" once heard a similar statement in an interview with a foreign brand bearing company: "There is no problem with small production, but the quality is not stable enough after mass production, and the product qualification rate needs to be improved."
　　Schaeffler also pointed out in the interview reply that domestic spindle bearings lack R&D and application verification capabilities, and most of them need to be entrusted to external teams, which is not conducive to risk control. There is still room for improvement in practical application experience and theoretical basis, which is still the advantage of imported brand spindle bearings.
　　According to Cang Shiliang, director of the Wind Power Spindle Bearing Research Institute of Wafangdian Bearing Group Co., Ltd. (hereinafter referred to as "Wafang"), the gaps at home and abroad include: First, in terms of calculation, foreign bearing suppliers started early, and the verification machine There are many types, and the theoretical analysis experience and actual assembly experience are relatively rich; the second is the bearing capacity, the bearing capacity of foreign spindle bearings is generally higher than that of domestic spindle bearings, which depends on the design concept of each company; third, in terms of production equipment, foreign manufacturers It is more advanced than the domestic one, with a higher degree of automation of the production line, complete with high-precision CNC lathes, double-end grinders, manipulators, robots and other equipment, and the coverage of high-precision equipment of domestic bearing manufacturers is lower.
　　In terms of equipment, the lack of test benches with large megawatt bearings is also a shortcoming. "The test bench is mainly to simulate the working conditions, through accelerated fatigue, monitoring temperature rise, grease cleanliness, loading force, etc., and finally dismantling to check the bearing wear condition to verify whether it is the same as the design goal. For the bench test of the tile bearing, the samples usually need to be transported to foreign experimental machines such as Siemens Gamesa, GE, Vestas, etc. for verification, and the price is high. A single test costs two or three million yuan, not including the freight. ." Fan Jiaqiao, Marketing Director of Chengdu Tianma Railway Bearing Co., Ltd. (hereinafter referred to as "Chengdu Tianma") told "Wind Energy".
　　It is understood that the 8MW offshore wind power main shaft bearing sample of Chengdu Tianma, which was offline in August 2021, has been sent to Siemens Gamesa's test bench in Denmark for testing, and the test is expected to be completed in July this year.
　　At present, domestic leading bearing manufacturers have increased their investment in software and hardware. The State Key Laboratory of Aeronautical Precision Bearings established by Luozhou is the only state-level enterprise key laboratory in my country's bearing industry. It has purchased a number of world-leading analysis software and testing equipment. 4 meters. At the same time, the high-standard main bearing production line of Luozhou Axis will be ready for production before the end of June this year. The intelligent production base project of Luozhou New Energy Equipment Bearing has been launched, and it is planned to benchmark imported bearings.
　　Luoyang Xinqianglian Slewing Bearing Co., Ltd. (hereinafter referred to as "Xinqianglian") introduced a fully CNC non-soft-belt quenching machine tool from SAET, Italy. After a long period of exploration, the technical requirements for quenching without soft-belt were realized.
　　According to Xu Meng, general manager of Zwazhou Wind Power Sales Company, the company is currently investing in a new wind power bearing factory, which is dedicated to the production of wind power spindle bearings, gearbox bearings and motor bearings. It is expected to be put into production in 2023.
　　In terms of testing equipment, the leading domestic wind power bearing enterprises have gradually invested in imported phased array ultrasonic flaw detectors, roundness meters, profilers, three-coordinates and other testing equipment since 2019, which is basically no different from foreign companies.
　　However, domestic companies still need to learn from foreign companies in terms of production line design, 5S management, and environmental transformation. "The factories of foreign companies are very clean. Whether the environment is good or not also reflects the management level from one aspect. At present, some domestic companies have made corresponding improvements in this aspect in the audit of becoming foreign brand suppliers, which is worth learning from domestic counterparts. "Wang Yi told "Wind Energy".
　　Localization requires opportunity and trust
　　On January 12, 2010, the requirement that the localization rate of wind power equipment be more than 70% was cancelled. The influx of foreign-funded enterprises almost monopolized the domestic spindle bearing market. Since 2020, the supply of imported spindle bearings has been limited due to the impact of foreign epidemics. With the advancement of the domestic dual-carbon goal, the number of orders from major bearing manufacturers has increased, and now they have begun mass production of products above 4MW.
　　In November 2021, the 4MW self-aligning main shaft bearing developed by Luozhou was exhibited at the National "Thirteenth Five-Year" Science and Technology Achievement Exhibition
　　Among them, the 7.0MW platform main shaft bearing of Luozhou Axis will be installed and operated in the middle of this year, and the 12MW main shaft bearing prototype under development is expected to be delivered before the end of this year.
　　According to Hao Wenlu, technical director of Xinqianglian, since the company's three-row cylindrical roller spindle bearings were mass-produced in 2011, the indicators of the bearings have reached or even exceeded those of foreign bearings. In terms of tapered roller bearings, 3~4MW products have been Mass production, products above 5MW are being produced in small batches.
　　In 2021, the impact of the epidemic will gradually ease, and some development companies require the use of imported brands for spindle bearings, which is a challenge for domestic spindle bearing manufacturers.
　　One of the common phenomena is that development enterprises are not very enthusiastic about using domestic spindle bearings. "Wind Energy" learned from the main shaft factory and the complete machine dealer that the resistance mainly comes from the development enterprises. Because the development enterprises are relatively concentrated and pursue the power generation efficiency of wind farms, they have a greater right to speak in the bidding and will specify the brand of installation components. The whole machine market is full of competition. In order to get the order, the whole machine manufacturer basically accepts all the conditions put forward by the developer, and these conditions will be passed up to the component manufacturer.
　　In this regard, Xu Meng said: "For newly developed products, I hope that partners can give domestic suppliers more opportunities. This is a process of cyclical improvement, and foreign brands are also constantly revising from failures to create high-quality products. We are willing to Shared risk with partners.”
　　It is understood that when the spindle factory is put into production, it usually invests a few more sets in order to have more opportunities for process exploration and debugging. If scrap products are generated, they will be borne by themselves to ensure the delivery of qualified products.
　　"In fact, the most important thing when developing enterprise procurement is application performance. Customers pay more attention to the supplier's process control ability and hardware level, such as whether to perform finite element analysis for simulation calculation, through testing machine experiments, hanging prototypes, In the end, it comes to engineering applications. However, the domestic spindle bearings started late, the market influence is limited, and the product running time is shorter than that of foreign bearing suppliers. It is also necessary for developers to increase their understanding of domestic suppliers' products, and at the same time, we need to enhance the level of software and hardware." Yu Haibo Analysis Road.
　　However, the introduction of wind power bearing processing equipment costs a huge amount of more than 10 million yuan, and compared with other bearing processing equipment, the application scope of wind power bearing processing equipment is single. If the production capacity of this model is eliminated from the market, the equipment cost will be difficult to recover.
　　"Due to the vertical joint relationship between manufacturers and machine manufacturers, each product has different forms and sizes, resulting in a variety of product types in the market. At the same time, due to the continuous reduction of domestic machine prices, prices and demand in the domestic market are not enough. The wind power market in Europe is relatively stable, with fewer product models and punctual schedules, but some domestic suppliers are more willing to take orders from foreign customers. At present, the most important work we do is integration and standardization. We hope to be able to select standard bearings on the same platform as much as possible in a series or a megawatt level. From the perspective of reliability, cost and operation and maintenance, It is also conducive to the construction and development of the platform." Yu Haibo appealed.
　　Seize the opportunity to speed up the localization process
　　In the context of the increase in installed capacity and the rapid growth of wind turbine output, the wind power bearing industry has entered a period of rapid development, and the localization of large-megawatt products is in urgent need of breakthroughs.
　　Major domestic bearing enterprises promote the process of localization of high-end bearings for wind power
　　According to the forecast of the Wind Energy Professional Committee (CWEA) of the China Renewable Energy Society, the compound annual growth rate (CAGR) of the domestic wind power bearing market will reach 13% from 2021 to 2025, and the annual output value is expected to reach 10.6 billion yuan. Among them, the offshore wind power bearing market space will exceed 2.1 billion yuan (about 20%). The cost of wind power bearings accounts for about 5% of the total cost of wind turbines, while the spindle bearings account for about 1.5%. Based on this calculation, the annual output value of wind power spindle bearings is about 3 billion yuan.
　　The price of domestic brands is generally lower than that of imported brands, which has more price advantages. Due to the long application time of spherical roller bearings, the raw materials and process processing are relatively mature, and the price is about 90,000 to 150,000 yuan due to different specifications and sizes, which is about 40% to 50% lower than imported products. The price of tapered roller bearings is more than 200,000 yuan, which is 20% to 30% lower than imported products. The failure rate of three-row cylindrical roller bearings is lower than that of foreign products, which can completely realize import substitution, and the price is 20%~30% lower than that of foreign products.
　　In the current market, spherical roller bearings and tapered bearings account for almost half. With the emergence of larger megawatt units, double-fed units also tend to choose the form of tapered roller bearings.
　　Fan Jiaqiao analyzed that it is expected that in three to five years, tapered roller bearings will account for 80%, spherical roller bearings will be reduced to 10% to 15%. Because as the model develops towards large megawatts, the load will become larger, and the use of spherical roller bearings will be limited.
　　Hao Wenlu said that if the limitations can be overcome, three-row cylindrical roller bearings will also have good development potential in 2-5 MW, and even 7 MW direct-drive units.
　　In the face of an all-round approach to parity, under the guidance of the dual-carbon target policy, the industry's willingness to reduce costs and increase efficiency has been further enhanced.
　　"Spindle bearings have reached a critical point, foreign supply is also restricted by various factors, and the price is high." Cang Shiliang believes, "With the improvement of the technical accuracy of domestic spindle bearings in recent years, combined with the performance of bearings during operation , in the next 3 years, domestic spindle bearings are likely to surpass imported brands. The price is on the one hand, the delivery capacity can be guaranteed on the other hand, the logistics and transportation distance is relatively short, coupled with the continuous improvement of the professional service team's technology, the accumulation of experience, the service will also be have an advantage.”
　　He suggested that the government should take the lead, with wind power manufacturers as the center, unite with component manufacturers and development companies, and jointly establish a test wind farm to find common solutions for the design, manufacture and use of bearings, so as to form a long-term, sustainable A new model of sustainable green development.
　　At present, the state has also issued an incentive policy for the first set, and bearing enterprises can participate in related scientific research projects with development enterprises. However, some industry insiders suggested that appropriate exemption measures should be added to further mobilize the enthusiasm of development enterprises to apply domestic spindle bearings. . CWEA
　　Source: "Wind Energy" Magazine Text/Wang Fang