遵循正确的技术方向合理确定西气东输二线技术方案

分析了国外发展长距离、大输量输气管道存在的两个不同的技术发展方向，指出我国事实上已经走上了与北美和西欧相似的技术发展道路，在建设西气东输二线时应当继续遵循这一技术方向。提出实施本项目任何技术方案的前提是所需要的管线钢和钢管必须基本立足国内，才能保证可靠的资源供给和减少投资，为此应当使该管道在一级地区能够使用螺旋缝埋弧焊接钢管。建议采用X80钢级、12MPa输气压力、1219mm（48in）管径的技术方案，这一方案的技术优势是:此时一级地区钢管的壁厚为18.4mm，国内可以提供全部X80钢级的热轧卷板和螺旋埋弧焊管。建议不再考虑管径1422mm的方案并分析了原因。指出要完成本项工程的关键是要有强有力的集中领导，能够把全国相关的力量协调起来，通力合作。建议在抓紧解决钢材、制管、弯管、管件等材料问题的同时，应注意以西气东输二线的需求带动高压、大直径输气管道关键设备的国产化。

Rationally Design the Technical Parameters for the Second WEGP Project Based on the Verified Developing Trend of Technology

The existing two different developing trends of technology for the long distance,large flow rate gas pipelines in the world were analyzed in this paper.Actually China has already made progress along the trend similar to what people have done in the North America and West Europe.Consequently China should go along this trend continuously to build up The 2nd WEGP Project.Pointed out that the precondition for any reasonable technological scheme of this project is that China could produce most of the steel plates,coils and linepipes needed by the scheme,to ensure the supply resources and lowering the cost.Therefore,it is necessary to use spiral welded pipes in the districts of 1st category.Suggest adopting the scheme with X80 grade,12MPa pressure and 1219mm diameter for the project,so that all the X80 steel coils and spiral welded pipes used for the 1st category districts could be produced domestically.Explain the advantages of this scheme and analyze the reasons of not introducing the 1422mm as diameter.Indicate that one of the key points to complete this project is forming a powerful leadership who could coordinate all the related enterprises and organizations in this country to cooperate closely.Advise paying attention to bring along the localization of the key equipments for the high pressure and large flow rate gas pipelines while solving the problems occurred in the areas of steel plates,pipes,induction heated bends and fittings.