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CN-122012903-A - Wind power main shaft and control method of residual stress of wind power main shaft

CN122012903ACN 122012903 ACN122012903 ACN 122012903ACN-122012903-A

Abstract

The invention discloses a wind power main shaft and a control method of residual stress of the wind power main shaft, and belongs to the technical field of manufacturing of large-sized high-end equipment. The method comprises the following steps of normalizing a wind power main shaft forging, tempering at a high temperature to obtain a first intermediate workpiece, rough machining and first stress relief aging treatment of the first intermediate workpiece, semi-finishing and second stress relief aging treatment of the first intermediate workpiece to obtain a second intermediate workpiece, and finishing and vibration aging treatment and deep cooling treatment of the second intermediate workpiece. The method can form a stable and uniform residual compressive stress layer on the surface of the wind power main shaft, can effectively inhibit the initiation and the expansion of fatigue cracks, and simultaneously improves the size stability, the wear resistance and the stress corrosion resistance.

Inventors

  • GAN CHUNLEI
  • LI XIAOHUI
  • SONG DONGFU
  • CHEN LIJIE
  • LIU LIANHAO
  • XU JING
  • NONG DENG

Assignees

  • 广东省科学院新材料研究所
  • 佛山大学
  • 中集海洋工程有限公司

Dates

Publication Date
20260512
Application Date
20260214

Claims (10)

  1. 1. A control method of residual stress of a wind power main shaft is characterized by comprising the following steps of normalizing a wind power main shaft forging, tempering at high temperature to obtain a first intermediate workpiece, rough machining and first stress relief aging treatment are carried out on the first intermediate workpiece, semi-finishing and second stress relief aging treatment are carried out on the first intermediate workpiece to obtain a second intermediate workpiece, and fine machining, vibration aging treatment and deep cooling treatment are carried out on the second intermediate workpiece.
  2. 2. The control method according to claim 1, wherein the normalizing treatment is performed at 870 ℃ to 890 ℃ for 6h to 10h.
  3. 3. The control method according to claim 1, wherein the high temperature tempering treatment is performed at 630 ℃ to 650 ℃ for 18h to 22h.
  4. 4. The control method according to claim 1, wherein the first stress relief aging treatment is performed by heating at a rate of 65 ℃ to 75 ℃ per hour to 550 ℃ to 600 ℃ and maintaining the temperature for 6 to 8 hours.
  5. 5. The control method according to claim 4, wherein the second stress relief aging treatment is performed by heating to 500 ℃ to 550 ℃ at a rate of 45 ℃ to 55 ℃ per hour and maintaining the temperature for 4 to 6 hours.
  6. 6. The control method according to claim 5, wherein after the first stress relief aging treatment, the furnace is cooled to 240 ℃ to 260 ℃ and then discharged for air cooling; and/or cooling to 170-190 ℃ along with the furnace after the second stress relief aging treatment.
  7. 7. The method according to claim 1, wherein the vibration aging treatment comprises performing multi-frequency vibration within a range from 20Hz to 200Hz, and maintaining the treatment for 25-35 min when the dynamic stress reaches 30% -40% of the theoretical yield strength of the material.
  8. 8. The control method according to claim 1, wherein the cryogenic treatment comprises cooling to-160 ℃ to-190 ℃ at a rate of 1.5 ℃ per minute to 2.5 ℃ per minute and maintaining the temperature for 2h to 4h.
  9. 9. A wind power main shaft, characterized in that it is obtained by the control method according to any one of claims 1 to 8.
  10. 10. The wind power spindle of claim 9, wherein the surface residual stress of the wind power spindle is a compressive stress of-200 MPa to-250 MPa; And/or the pressure distribution uniformity of the wind power main shaft is more than or equal to 90%.

Description

Wind power main shaft and control method of residual stress of wind power main shaft Technical Field The invention relates to the technical field of manufacturing of large-sized high-end equipment, in particular to a wind power main shaft and a control method of residual stress of the wind power main shaft. Background The wind power main shaft is a core transmission component of the wind power generator set, has a severe service environment and needs to bear complex alternating load, torque and wind load impact. Because wind power main shafts are usually formed by forging and heavy cutting large forgings (such as 42CrMo4, 34CrNiMo6 and other alloy steels) repeatedly, a large amount of macroscopic and microscopic residual stresses are inevitably generated in the manufacturing process. These residual stresses are the main contributors to the deformation of the spindle after machining, poor dimensional stability, and reduced fatigue performance in service, even with early stress corrosion cracking. At present, one of the residual stress relief methods commonly used in the industry is stress relief annealing, and the other is natural aging. The former can eliminate partial stress, but has the problems of long production period (usually requiring tens of hours), high energy consumption, difficult control of the overall heating uniformity of large-scale workpieces, and the like, and can not effectively interfere with new stress introduced by machining, while the latter takes too long (months or even years), and is difficult to meet the requirement of efficient production. In view of this, the present invention has been made. Disclosure of Invention The invention aims to provide a wind power main shaft and a control method of residual stress thereof so as to solve or improve the technical problems. The invention can be realized as follows: The invention provides a control method of residual stress of a wind power main shaft, which comprises the following steps of normalizing a wind power main shaft forging, tempering at high temperature to obtain a first intermediate workpiece, rough machining the first intermediate workpiece, performing first stress relief aging treatment, performing semi-finishing and second stress relief aging treatment to obtain a second intermediate workpiece, and performing finish machining, vibration aging treatment and deep cooling treatment on the second intermediate workpiece. In an alternative embodiment, the normalizing treatment is carried out for 6-10 hours under the condition of 870-890 ℃. In an alternative embodiment, the high temperature tempering treatment is carried out at 630-650 ℃ for 18-22 hours. In an alternative embodiment, the first destressing aging is heated to 550-600 ℃ at a rate of 65-75 ℃ per hour and held for 6-8 hours. In an alternative embodiment, the second stress relief aging treatment is heated to 500-550 ℃ at a rate of 45-55 ℃ per hour and incubated for 4-6 hours. In an alternative embodiment, after the first stress relief aging treatment, cooling to 240-260 ℃ along with the furnace, and discharging and air cooling; and/or cooling to 170-190 ℃ along with the furnace after the second stress relief aging treatment. In an alternative embodiment, the vibration aging treatment comprises multi-frequency vibration within the range of 20Hz to 200Hz, and the treatment is maintained for 25-35 min when the dynamic stress reaches 30-40% of the theoretical yield strength of the material. In an alternative embodiment, the cryogenic treatment comprises cooling to-160 ℃ to-190 ℃ at a rate of 1.5 ℃ per minute to 2.5 ℃ per minute and maintaining the temperature for 2 hours to 4 hours. In a second aspect, the invention provides a wind power main shaft obtained by the control method according to any one of the preceding embodiments. In an alternative embodiment, the surface residual stress of the wind power main shaft is the compressive stress of-200 MPa to-250 MPa; And/or the pressure distribution uniformity of the wind power main shaft is more than or equal to 90 percent. The beneficial effects of the invention include: The method provided by the invention realizes closed-loop management of generation-elimination-regeneration-elimination of residual stress by leading and penetrating the stress control node into the whole process of forging-rough machining-semi-finishing, and controls stress accumulation from the source. The vibration aging treatment and the cryogenic treatment are matched, so that the advantages of rapid vibration homogenization stress and thorough cryogenic stress relief are combined, the vibration aging treatment provides a more active microscopic state for the cryogenic treatment, the cryogenic treatment consolidates and deepens the effect of the vibration aging treatment, and the vibration aging treatment and the cryogenic treatment are matched with each other, so that the effect of far and ultra-single process can be achieved in a short time. Compared with