On March 18, 2008, a significant milestone was achieved at China's Double Forging Plant when a turbine forging shaft with a diameter of 4,125 mm was successfully machined. This was the main shaft for China’s two-way turbine system and marked the largest forged shaft body ever processed by the company to date. The shaft featured an annular groove on its outer surface, with a minimum width of 38 mm and a total length of 395 mm. The machining was carried out using a 20-meter heavy-duty lathe, whose tool holder was specifically designed and manufactured by China DuPont Forging Factory. However, the tool holder had a maximum machining diameter of only 2,700 mm, which posed serious challenges in terms of workpiece fixation and feeding. To address these issues, the workshop technicians and machine operators collaborated closely to develop custom solutions. They designed and fabricated a center support sleeve and high-strength support claws to securely hold the workpiece in place. In addition, they extended the tool holder using a lever mechanism to allow for a machining length of up to 1,000 mm. Due to the extension, the tool holder’s rigidity was significantly reduced, making it more prone to vibration and deformation. To mitigate this, the technicians implemented a step-by-step extension method as the machining depth increased, allowing them to maintain stability while minimizing tool wear and mechanical stress. Through their combined efforts and innovative problem-solving, the team successfully completed the machining of this oversized turbine forging shaft, showcasing both technical expertise and determination. This achievement not only demonstrated the capabilities of China’s manufacturing industry but also set a new standard for large-scale forging and machining processes.

ShenZhen Jakeconn Precision Technology Co., Ltd. , https://www.jakeconn.com