On October 13, the opening ceremony of the 14th China International Patent Technology and Products Fair and the 25th China Patent Award Presentation Conference were held in Dalian, Liaoning. The invention patent of CREG, "A Pipe Jacking Machine for Three-Lane Rectangular Tunnel Construction," stood out and won the China Patent Gold Award, and was commended at the conference.

This is the second time the company has won the Patent Gold Award in this field, following "Shield Machine for Tunnel Cross Passage and Its Cross Passage Excavation Method," marking a major breakthrough in China's high-end equipment for underground space development and providing a new technical solution for urban tunnel construction.

During the fair, the "Three-Lane Rectangular Pipe Jacking Machine" model and related technological achievements exhibited by CREG attracted much attention, drawing many attending leaders and professional visitors. Lu Pengqi, Deputy Director of the China National Intellectual Property Administration, visited the CREG booth, focusing on the patented gold award product model, and expressed great concern about the development trend of domestic full-face tunnel boring machines in the international market, encouraging the company to continue deepening technological innovation and strengthening the protection and application of intellectual property.

A Pipe Jacking Machine for Three-Lane Rectangular Tunnel Construction

The rectangular pipe jacking machine is an innovative underground engineering construction equipment used for urban highway tunnels, underground pedestrian passages, underground commercial and civil air defense projects, etc. With the rapid development of comprehensive underground space development and higher requirements for efficient, safe, and environmentally friendly construction, equipment innovation faces new challenges. The awarded patent innovatively solves the problem of low space utilization efficiency in traditional circular tunnels, and can form a three-lane rectangular cross-section tunnel in one pass, effectively improving tunnel space utilization and reducing the impact of construction on the surrounding environment. Based on this patent, CREG developed the world's first three-lane rectangular pipe jacking machine, "Nanhu," and successfully applied it to the tunnel project under Nanhu Avenue on the Jiaxing urban expressway ring line in Zhejiang.

The tunnel project adopts a two-way 6-lane design, crossing through plain fill, silty clay, mucky silty clay, and other geological layers, with a tunnel cover depth of 5.68 to 6.54 meters. During construction, settlement must be precisely controlled to ensure safe traffic on the road surface while reducing the impact on the surrounding environment, placing extremely high demands on equipment and construction.

CREG carried out customized design for the project. "Nanhu" is 14.82 meters wide and 9.446 meters high. The machine adopts a "6 front + 8 rear" multi-cutterhead combined excavation design, optimized shield body block design, multi-screw machine mucking design, automatic friction reduction, and information-based detection technologies, solving technical challenges such as one-pass excavation forming for super-large cross-section rectangular pipe jacking machines, main machine posture control, and soil settlement control. It features no traffic disruption, no environmental damage, and safe and efficient operation, and pioneered the successful application of rectangular pipe jacking machines in one-way 3-lane rectangular tunnel construction.

Continuous Deepening of Rectangular Pipe Jacking Machine R&D

For a long time, the company has continued to deepen its research and development of rectangular pipe jacking machines, constantly seizing the world's technological high ground. From the "Zhongyuan No. 1" rectangular pipe jacking machine tailor-made in 2013 for the Hongzhuan Road underpass project on Zhongzhou Avenue in Zhengzhou, Henan, to the world's largest cross-section combined rectangular pipe jacking machine "Dayu · Tunneling" developed in 2023, the company has always adhered to an industry-university-research-application innovation mechanism, completing the transformation from catching up to leading.

In December 2016, the "Super-Large Cross-Section Rectangular Shield" project won the Gold Award at the 2nd "China Good Design." In January 2019, the project "Key Technologies for Design and Manufacturing of Special-Shaped Full-Face Tunnel Boring Machines and Their Application," which the company led the application for, won the Second Prize of the 2018 National Science and Technology Progress Award. In September 2019, the rectangular shield machine was successfully selected for the "Great Journey, Glorious Achievements—Exhibition Celebrating the 70th Anniversary of the Founding of the People's Republic of China."

Up to now, the company has designed and manufactured more than 30 rectangular pipe jacking machines, widely used in urban pedestrian tunnels, utility tunnels, underground parking lots, and other fields. It holds more than 40 authorized national invention patents and over 50 utility model patents in related fields, and has led the formulation of 2 national standards. This has not only promoted the collaborative innovation of new construction methods and new equipment for underground space development, but also led technological progress in the field of underground space development, making positive contributions to China's urban underground space construction.