Weidu News, recently, China's first fully domestically produced heavy-duty electric servo stretching pad, with its core component—the largest-specification heavy-duty planetary roller screw—independently developed by the 704 Research Institute under China State Shipbuilding Corporation Limited, successfully passed rigorous full-process processing, performance testing, and verification at China First Heavy Industries Tianjin Heavy Industry Co., Ltd., and has officially entered mass production and deployment. This marks the end of decades of technological monopoly by overseas enterprises and fills the gap in China's independent development of core equipment for high-end stamping production lines.
The heavy-duty electric servo stretching pad is a core piece of equipment in automotive stamping production lines, directly determining the quality of body stamping and the overall vehicle manufacturing capacity. Among its components, the large-scale heavy-load planetary roller screw is the key core component enabling the servo stretching pad to achieve high precision and stable operation under heavy loads.
A planetary roller screw is a high-precision, high-load-capacity mechanical transmission device that transmits force and motion through the planetary movement of rollers between the screw shaft and nut. It features high load capacity, high precision, high rigidity, and high transmission efficiency, and is widely used in aerospace, marine, precision machine tools, industrial automation, and humanoid robots. For a long time, the design, manufacturing, and testing technologies for large-specification, high-load precision screws have been monopolized and blocked by overseas enterprises, becoming a key bottleneck restricting the localization of China's stamping equipment.
In the process of customizing the 150mm diameter, 220-ton rated load—China's largest-specification heavy-duty planetary roller screw—for the localization technology research project of China First Heavy Industries Tianjin Heavy Industry's heavy-duty electric servo stretching pad, the 704 Research Institute leveraged its deep expertise in precision transmission technology and flexible production system. It coordinated the entire chain of design, process, processing, and testing for efficient synergy, innovatively constructing a new design system for large-specification heavy-load screws. It successively overcame multiple industry technical barriers, including uniform heat treatment of ultra-large components, precision grinding of large-diameter threads, and simulation matching of heavy-load meshing. Notably, within just three months, it fully completed the entire workflow from forward design, special process development, and whole-machine performance verification to product delivery, forming an integrated R&D and manufacturing system tailored for large-specification planetary roller screws. This achievement produced the heavy-duty planetary roller screw, hailed as "unyielding steel backbone," breaking through technical barriers to support the localization and substitution of China's high-end automotive stamping line equipment. It realized a brilliant cross-industry transition from shipbuilding to the automotive industry, significantly enhancing China's complete independent supporting capabilities integrating R&D, manufacturing, and application in the field of heavy-load precision transmission, demonstrating the responsibility and commitment of central state-owned enterprises.
The delivery and deployment of China's first fully domestically produced heavy-duty electric servo stretching pad fundamentally eliminates the inherent defects of traditional hydraulic stretching equipment, such as high energy consumption, poor forming precision, slow dynamic response, and high maintenance costs, from the core transmission end. It fills the gap in key components for heavy-duty electric servo stretching equipment, opens up a fully autonomous and controllable channel for the entire chain of high-end automotive stamping equipment, and provides robust support for China's high-end stamping lines to completely break free from overseas technological constraints, contributing to the high-quality development of China's automotive industry.