![The world's smallest diameter atmospheric cutter head shield machine]( "The world's smallest diameter atmospheric cutter head shield machine")
On March 31, 2021, the atmospheric pressure cutterhead TBM “Changtong” with the world's smallest diameter (7.95m), developed by China Railway Engineering Equipment Group Co., Ltd. affiliated to CRHIC, is launched in Shanghai. The machine will be used in the Yangtze River Tunnel Project of China-Russia East-Route Natural Gas Pipeline Project (Yongqing-Shanghai), which is the longest underwater tunnel under construction, and it will set the record of underwater TBM blind heading distance in China.
![The world's smallest diameter atmospheric cutter head shield machine]( "The world's smallest diameter atmospheric cutter head shield machine")
The China-Russia East-Route Natural Gas Pipeline Project, being an important strategic energy cooperation project between China and Russia which is instructed, witnessed and promoted by General Secretary Xi Jinpinga, is a model project of implementing such national strategies as the “Belt and Road Initiative”, the “Four Revolutions and One Cooperation” and the “High-quality Development of the Yangtze River Economic Belt”, and also an integral part of China's four major oil and gas strategic channels.