论文部分内容阅读
中俄东线天然气管道是中国首条大口径OD 1 422 mm输气管道,途经东北严寒地区,钢级为X80、设计压力为12 MPa,其断裂控制设计是难点。结合断裂失效模式,明确了该工程断裂失效的控制原则。根据中俄东线管输天然气组份、管道壁厚、流变应力、运行温度及管沟回填等参数,采用断裂力学理论及相关模型计算了钢管焊缝和热影响区的起裂韧性、钢管管体止裂韧性以及环焊缝的起裂韧性,制定了中俄管道的钢管和环焊缝韧性指标。对比工程推荐采用的指标,该断裂韧性推荐指标在符合计算需求量的基础上,均有一定的裕量,能够满足管道的断裂控制要求。同时为了确保管道吊装下沟时环焊缝安全,对管道的韧脆转变温度和下沟温度下限值提出了建议。
The Sino-Russian eastern natural gas pipeline is the first large-diameter OD 1 422 mm gas pipeline in China. It passes through the northeast cold region with a steel grade of X80 and a design pressure of 12 MPa. Its fracture control design is difficult. Combined with the failure mode, the control principle of the failure of the project is clarified. According to the parameters of natural gas components, pipe wall thickness, flow stress, operating temperature and gully backfill of the East China Line, the fracture toughness of the weld and HAZ of the pipe was calculated by using fracture mechanics theory and related models. The pipe body crack toughness and the initiation fracture toughness of the girth weld, the toughness index of the steel pipe and the girth weld of the Sino-Russian pipeline has been worked out. Comparing with the engineering recommended index, the fracture toughness recommendation index has a certain margin on the basis of meeting the calculation demand, and can meet the pipeline fracture control requirements. At the same time, in order to ensure the safety of the girth welds when the pipe is hoisted, the ductile-brittle transition temperature of the pipe and the lower groove temperature limit are put forward.