Wavelet transform and mathematic morphology algorithms are used to process multi-pass seam image to get weld pass and groove 's edges .

结合二维小波变换方法与数学形态学方法对多层焊填充层焊道图像进行处理，实现对 焊道边缘及坡口边缘的提取。

Conventional TIG welding is known as its low productivity and limited weld depth in a single pass .

常规TIG焊生产效率低，单 道焊可 焊厚度小。

The etched section also reveals that multiple weld passes were made over the top of the original submerged arc weld pass .

从酸蚀断面还可以看出：在原自动埋弧焊的上面覆盖有多层 焊道。

The pipeline girth weld is composed of different passes such as the root pass hot pass filler and cap passes etc.

管道环 焊缝是由根 焊、热焊、填充 焊、盖面 焊等不同焊道组成。

Weld seam formation control of root pass for pipeline MIG welding based on an embedded DSP visual servo platform

基于嵌入式DSP视觉伺服平台的管道MIG 打底焊 焊缝成形控制