埋地钢质管道新型三层PE防腐层的结构设计

以我国用于埋地长输螺旋焊缝钢质管道三层PE防腐层的结构在原《埋地钢质管道聚乙烯防腐层技术标准》（SY／T4013－95）的基础上进行了新结构设计和耐蚀性研究。提出了FBE层的新结构方案即FBE厚度为120－160μm；粘胶剂层厚度为170－250μm；三层PE防腐层厚度为1.8-2.0mm；焊缝处防腐层厚度不低于1.0mm。在保持防腐性能的前提下，对防腐层结构进行调整，合理减薄聚乙烯层厚度，增加环氧粉末厚度，实现防腐层最佳的性价比，减少成本投资。

Structural Design on the Polyethylene Coating of Long Distance Buried Spiral-Welded Steel Pipeline

The new structure design and research on multi-polyethylenecoating of long distance buried spiral-welded steel pipeline have been carried out based on some standards and codes like CAN/CSA-Z245.21 98 and SY/T4013 95 and the corresponding foreign standards．A new kind of structure for the multi-polyethylene coating of oil/gas pipeline has been proposed．The technical data for the FBE coating is that the thickness of FBE layer is between 120～160 μm，the thickness of binder layer is between 170～250 μm；the PE thickness is between 1.8～2.0 mm，the thickness of coating layer at spiral seam is not less than 1.0 mm．The authors consider that this new multi-polyethylene coating can achieve a optimal performance price ratio and decrease production cost，but it needs to be further verified in actual site application．