A sketch of the southern part of the China-Russia east-route natural gas pipeline, which started construction in Haimen district, Nantong on July 28 [Photo/WeChat account: haimendianshitai]

A construction of a shield structure that is a key part of the China-Russia east-route natural gas pipeline started in Haimen district, Nantong on July 28.

The structure is a tunnel through which natural gas from Russia is transported to Shanghai. It is also the only channel across the Yangtze River that allows for natural gas to be transported to Jiangsu province.

The structure has an inner diameter of 6.8 meters, a horizontal length of 10.23 km and a maximum water pressure of 0.73 Mpa, setting a list of world records for cross-river shield structure construction with the longest single tunneling distance, deepest buried depth, highest water pressure and largest diameter in the oil and gas pipeline field.

The 5,111-kilometer China-Russia East natural gas pipeline is divided into three parts: north, south and middle. The northern segment was put into operation last year, while the middle section is expected to be completed by the end of this year. 

The tunnel belongs to the southern part, which stretches from Yongqing county in Hebei province to Baihe town in Shanghai. It is scheduled to be completed in June 2025.

By then, the pipeline is expected to transport 18.9 billion cubic meters of natural gas from Russia to the Yangtze River Delta region every year.