GB/T13793-1992直缝电焊钢管管道环焊缝多焊炬自动内焊机关键技术分析
Analysis on key technologies for pipeline internal circumferential automatic welding machine with multi-torch
高频直缝电焊钢管焊接质量的控制
Control of Weld Quality of Longitudinally High-Frequency Welded Pipe