first pass,sound weld metal 请教在句中什么意思? on plate test coupons which are vertically welded, the first pass may be run downwards,provided that it has been completely removed to sound weld metal in the preparation for welding the second side 我是这样翻译的:板材试件垂直焊接,首过可能向下,若其已经完全移动,则应测量焊接金属一杯第二遍焊接。 请各位指点一下,发表一下你们的建议查看更多