Summary and cognition on safe operation for Mohe-Daqing Crude Oil Pipeline

Sino-Russian Mohe-Daqing Crude Oil Pipeline is the first large-diameter and long-distance oil pipeline passing through permafrost areas in China. It attracts unprecedented attention because of its special geographic position, hostile operation condition and difficulty in maintenance. This paper gives an overview on the basic information of this transnational pipeline and analyzes all kinds of risks encountered since its operation in detail, introduces the methods and successful experiences in the countermeasure against the risks and summarizes all kinds of achievements since the operation including a series of precautions and prevention measures like prudent defect repairs, management of frozen earth disaster and transformation of low temperature maintenance equipment. Based on analysis results and experience summary, this paper puts forward optimization suggestions on the design and construction process of pipeline in extremely cold permafrost areas, which can provide a reference to the design, construction and technology development of pipelines in extremely cold areas in China.