Design and manufacturing key technologies for low temperature monolithic insulation joints on the OD 1 422 mm X80 pipeline

In the China–Russia Eastern Gas Pipeline Project, large diameter (OD 1 422 mm), high pressure (12 MPa) and high grade steel (X80) pipelines were used to transport huge amounts of natural gas, so as to meet the needs of energy strategy. However, with the increase of pipe diameter, transmission pressure, steel grade and design coefficient, and the reduction in ambient temperature, the design and manufacturing difficulties of monolithic insulation joints have become the focus of the research. A series of technical innovation have been made and filled the domestic blank, e.g., the development of the monolithic insulating joints on the OD 1 422 mm X80 pipeline, the research on the key technologies for monolithic insulating joints in cold regions, the construction of large hydraulic pressure and bending test device. Therefore, a complete set of technology and equipment has been formed for the design and manufacture of monolithic insulation joints on OD 1 422 mm X80 pipeline, having great significance to the construction of natural gas pipeline in the China–Russia Eastern Gas Pipeline Project.