In wind power equipment, shaft forgings, as key transmission components, directly affect the operational reliability and service life of wind turbines. A wind power machinery factory in Shangrao, Jiangxi (hereinafter referred to as "the factory") encountered multiple technical challenges during the mass production of shaft forgings. To improve product quality and production stability, the factory partnered with Jianing Forging to jointly optimize the manufacturing solutions for shaft forgings.

Customer pain points

The factory faced three major bottlenecks in the early stages of production:

• Material performance fluctuations: Some batches of forgings have unstable fatigue strength and toughness, leading to early failure of finished products during bench tests.
• Insufficient dimensional accuracy: Under traditional forging processes, shaft-type forgings have large coaxiality and roundness deviations, making it difficult to control subsequent finishing allowances, which increases defect rates and processing costs.
• Tight delivery cycles: The plant's order volume continues to grow, but the original forging suppliers face capacity constraints and lack specialized process support for the wind power industry, making it difficult to meet requirements for rapid delivery and consistent quality.

Product advantages

To address these pain points, Jianing Forging offers a customized overall shaft forging solution:

• Material selection and validation: Alloy structural steel that meets wind power industry standards (such as 34CrNiMo6) is selected. Each batch undergoes chemical composition analysis and low-magnification microstructure testing, helping to ensure the purity and uniformity of raw materials.
• Multi-directional forging process: uses multiple heats and high pressure forging to effectively break the cast structure, refine grains, and improve internal density and isotropy of forgings. By controlling forging temperature and deformation, product performance is stably met customer requirements for tensile strength and low-temperature impact toughness.
• Fine shape control and heat treatment: Equipped with CNC ring grinding machines and specialized molds, it achieves efficient forming of shaft forgings, with dimensional tolerances controlled within ±1.5mm. Subsequent quenching and tempering treatment (quenching + high-temperature tempering) is used, equipped with a real-time temperature monitoring system to help hardness uniformity deviation below 3HRC.
• Full-process inspection system: Each forging undergoes ultrasonic testing (UT) and magnetic particle testing (MT), with mechanical property retesting added to key areas. Inspection data is archived and traceable, providing customers with complete quality reports.

Through these improvements, the first-pass pass rate for shaft forgings has risen to over 99%, finishing allowance has decreased by 30%, and the overall production cycle has been shortened by 15%. Since their cooperation, more than 2,000 shaft forgings have been delivered in total, with no batch quality feedback occurring.