土堤敷设管线
earth embankment lay pipe
导线穿管敷设
conductor installed in conduit
X80电阻焊管线管
X80 grade electric resistance welding linepipe
地下管线管理
underground pipeline management
Management of Underground Pipelines
地下管线管理系统
underground pipeline management system
钩形集极晶体管管线
hook collector transistor
管线管理系统
tubeline management system
海底无缝管线管
submarine seamless line pipe