中亚天然气管道工艺细节设计

针对中亚天然气管道项目工艺设计中钢管低温脆性、管道水压试验、阀门压力等级和材质选择、放空立管防雨水功能4个代表性问题进行了分析。在低温时,通过采取保温措施、控制材料低温韧性或制定相应站场操作原则,避免管道出现低温脆性断裂;关于管道水压设计,设计方在提交给钢管厂家的技术条款中应增加现场强度试压的压力值和试压所维持时间的信息项,钢管厂家投标时应将工厂内的水试验压力指标列入标书中;在选择阀门压力等级和材质方面,采用标准磅级、特殊磅级、提高磅级或者中间额定4种方案,以解决阀门不满足设计压力和设计温度要求的问题;针对目前中亚项目放空立管防雨水存在的缺陷,提出了新的放空立管设计方案。

Process-oriented design of Trans-Asia Natural Gas Pipeline

With regard to four typical problems existed in the process design ofTrans-Asia Natural Gas Pipeline,the fragility of pipe under lowtemperature,pipeline hydrotest,pressure grade and material selection of valves,waterproof of vertical venting pipe are analyzed.Under low-temperature,cracking of pipe can be prevented by insulating,controlling low-temperature flexibility of material and transforming corresponding codes for the construction of pump station.For the determination of water pressure,the design party provides the information about "pressure strength of field hydrotest and hydrotest duration" to the technical clauses to pipe supplier,and the pipe supplier lists the relevant yard hydrotest indices in bidding contract.For the selection of pressure grade and material of valves,the requirements in the design pressure and temperature are satisfied by applying standard class,special class and enhanced class or rated class.Considering the waterproof design defect in venting vertical pipe,a new design scheme is presented based on international design theory.