70年代末从国外引进换热器内孔焊技术,相继从国外又引进了高性能的管子、管板专用焊接设备。国内也研制出类似的焊机。由于焊枪结构的限制,内孔焊接深度一般在200mm左右(见图1),更远距离的内孔焊工艺在国内还未见报导。为解决更远距离的内孔焊接,我们 The late 70s imported heat exchanger from abroad hole welding technology, one after another from abroad and the introduction of high-performance pipe, tube sheet welding equipment. Domestic also developed a similar welding machine. Due to the structure of the torch, the depth of the inner hole welding is generally around 200mm (see Figure 1). The inner hole welding technology with longer distance has not been reported yet in China. In order to solve the more long distance bore welding, we