Advancements and development trends in plastic forming technologies of hollow shafts

As a core component in the industrial sector， the efficient and high-precision forming of hollow shafts is crucial for ensuring product performance and improving production efficiency. However， traditional open die forging and closed die forging methods face significant challenges， such as low material utilization， insufficient forming precision， and limited production efficiency. These issues severely restrict the development and application of hollow shafts. This paper reviews the latest research advancements in hollow shaft manufacturing， analyzes the current technical challenges， and explores the prospects of emerging forming technologies as well as the application of digital and intelligent technologies in this field. The paper summarizes the applications and advantages of various technologies， including rotary forging， squeeze casting， wedge cross rolling， and three-roll skew rolling， in enhancing the manufacturing efficiency and forming precision of hollow shafts. Rotary forging， by rotating and forging the material， effectively improves material utilization and product performance. Squeeze casting achieves high precision and consistency by pressing liquid metal into molds under high pressure. Wedge cross rolling drives the billet through the mold for reverse rotation， causing radial compression and axial elongation deformation of the metal， ultimately forming the desired stepped shaft parts， thereby improving dimensional accuracy and production efficiency. Three-roll skew rolling technology optimizes the loading mechanism to achieve efficient and continuous axial plastic forming through localized loading. With the manufacturing industry moving towards digitalization and intelligence， hollow shaft manufacturing technology is expected to achieve significant advancements and breakthroughs in the future.