Fujian Zhongtian Transportation participated in the “2021 National Symposium on Maintenance and Upkeep of Tunnels and Underground Engineering, Leakage Control, Flood Disaster Prevention, and Technological Innovation Exchange & Observation Meeting.”

From June 5 to 6, 2021, the National Symposium on Maintenance and Upkeep of Tunnels and Underground Engineering, Leakage Control, Flood Disaster Prevention, and Technological Innovation in Construction was held in Chengdu. Experts attending the symposium and delivering reports included Chen Kui, a senior expert at China Railway Tunnel Bureau and a professor at Shenzhen University; Zhou Jianjun, deputy director of the State Key Laboratory of Shield Tunneling and Excavation Technology; Zhang Longguan, member of the Party Committee, Deputy General Manager, and Chief Engineer of China Railway Engineering Corporation Services; and Zhang Yanbo, General Manager of Fujian Zhongtian Transportation Engineering Technical Services Co., Ltd.

Zhao Yunlong, representative of Spain’s Zitron Company in China and a traffic technology consultant at Fujian Zhongtian, delivered a presentation at the conference titled “Key Technologies for Ventilation in Long Tunnels of the Sichuan-Tibet Railway.” In his presentation, Zhao provided an in-depth discussion on how to perform ventilation calculations and select appropriate fans, addressing the five major challenges faced during the construction of long tunnels on the Sichuan-Tibet Railway: high altitude, high geothermal heat, low temperatures, high ultraviolet radiation, and prolonged construction periods.

During the post-meeting exchange, Zhang Yanbo from Fujian Zhongtian Traffic Engineering Technical Service Co., Ltd. pointed out: The complexity of temporary ventilation during tunnel construction lies in the fact that, although theoretical calculations can predict the ventilation effect on-site, such predictions are rarely confirmed in practice. The underlying reason is that these calculations fail to account for wind pressure; without sufficient wind pressure, it’s impossible to deliver the required airflow to the intended locations. Moreover, the airflow output of fans is seldom precisely controlled, leading to discrepancies between the calculated and actual airflow requirements. In contrast, ZITRON (Yu Tie Long) fans feature precise airflow calculations throughout the entire construction process, ensuring that the required airflow at each location closely matches the actual demand. In Section 3 of the Dianzhong Water Diversion Project—Dali Segment 1, the large fan supplied by China Railway Tunnel Bureau for Xianglushan, model 2xZVN1-20-630/4, has a ventilation distance of 2,000 meters, operates at a variable frequency of 15 Hz, and consumes only 40 kilowatts per hour. Its ventilation range reaches 3,400 meters, with a return air velocity of 0.5 meters per second and energy consumption below 55 kilowatts. Yu Tie Long boasts the world’s largest AMCA-certified civil aerodynamic laboratory, achieving an accuracy rate exceeding 99%. During testing, a third-party notary agency, BV, dispatches personnel to the site for on-site verification and issues a formal test report. Since obtaining the exclusive domestic agency rights for Spanish ZITRON fans in 2019, Fujian Zhongtian Traffic has already validated the superior performance and low energy consumption of Yu Tie Long fans in numerous projects across China. Furthermore, Yu Tie Long fans will soon be showcased in China’s largest-diameter shield tunneling project—and the one with the longest total tunneling mileage—demonstrating their outstanding capabilities once again.

More than 200 scholars attended this innovation exchange and observation conference, during which the participating experts shared a total of 14 thematic reports.