针对中俄东线高钢级大口径输气管道自动焊的设计提升

中俄东线天然气管道首次选用外径1 422 mm、输送压力12 MPa、X80钢级的设计参数组合，并且首次全面采用自动焊施工。为了提高自动焊的焊接效率、保证焊接质量，从管道线路选线、管道敷设、材料及焊接等方面对设计方法和技术进行了改进与提升，重点针对管道路由选择、管道转向、管道穿越障碍物、线路用管技术条件、不等壁厚焊接坡口和管道可靠性校核等方面开展了相关技术研究。研究结果表明：①在线路选线原则上尽可能地保持线路走向顺直，坡度控制在12°以下；②在管道转向设计中，在空间允许范围内尽可能地使用大角度弹性敷设代替冷弯管和热煨弯管；③在穿越等级公路时，优先采用了新式盖板涵代替传统套管；④在管材方面，加强钢管不圆度等参数控制；⑤在焊接方面，采用新型不等壁厚内孔锥形焊接坡口；⑥在管道整体安全性方面，进行线路可靠性评价。结论认为，上述设计提升措施有效地提高了自动焊的施工效率和焊缝质量，使管道线路段的可靠性能够满足规范中的目标可靠度要求，在中俄东线的自动焊现场实施过程中取得了显著成效，可以为自动焊在后续工程中的全面应用提供技术支撑。

Design improvement measures for the automatic welding of high-steel-grade and large-diameter gas line pipes in the project of the China–Russian Eastern Gas Pipeline

The design parameter combination of OD 1 422 mm, transportation pressure 12 MPa and steel grade X80 is adopted in China–Russian Eastern Gas Pipeline for the first time, and automatic welding is fully carried out for the first time. In order to improve the welding efficiency of automatic welding and ensure the welding quality, this paper improved and upgraded design methods and technologies from the aspects of pipeline route selection, laying, material and welding. And a series of technological researches were carried out mainly on pipeline routing, pipeline turning, pipeline crossing obstacles, technological condition of line pipes, welding groove with unequal wall thickness and pipeline reliability check. And the following research results were obtained. First, according to the route selection principles, the route shall be kept smooth and straight as much as possible and the slope shall be controlled below 12°. Second, in the design of pipeline turning, wide-angle elastic laying shall be used to replace cold and hot bends as much as possible within the allowable space. Third, in crossing a highway, a new type of slab culvert is preferentially adopted to replace the traditional casing. Fourth, speaking of pipe materials, it is necessary to strengthen parameter control, e.g. out of roundness. Fifth, as for pipeline welding, a new type of inner conical welding groove with unequal wall thicknesses is adopted. Sixth, to ensure the overall pipeline safety, route reliability shall be evaluated. In conclusion, above mentioned design improvement measures effectively improve the construction efficiency and seam quality of automatic welding, so the reliability of pipeline section can reach the target value stipulated in the regulation. Their application to the automatic welding of the China–Russian Eastern Gas Pipeline is remarkable, and they can provide technical support for the full-scale implementation of automatic welding in the following projects.