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 a two-way turbine system and marked the largest forged shaft body ever processed by the company to date. The complexity of the task was immense, as the shaft required an annular groove to be machined on its outer edge. The groove had a minimum width of 38 mm and a total length of 395 mm, making it a highly challenging operation. The machining was carried out using a 20-meter heavy-duty lathe, which was manufactured by China DuPont Forging Factory. However, the machine had limitations—its maximum machining diameter was only 2,700 mm, while the tool holder itself was just 350 mm in diameter. These constraints posed two major challenges: securing the workpiece firmly and ensuring stable feeding during the process. To overcome these difficulties, the workshop technicians and machine operators collaborated closely. They designed and fabricated a custom center support sleeve and high-strength support claws to stabilize the workpiece on the lathe. Additionally, they extended the tool holder using a lever mechanism to allow for a machining length of up to 1,000 mm. However, extending the tool holder significantly reduced its rigidity, increasing the risk of vibration and tool deflection. To address this, the team employed a step-by-step extension method for the tool holder rod as the depth of the groove increased. This approach helped minimize the impact of tool flexibility and reduced mechanical waste. Through their combined expertise and dedication, the team managed to complete the machining of this oversized turbine forging shaft successfully. It was not just a technical achievement, but also a testament to the teamwork and innovation that defined the project.

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