in excess on 怎么理解? if the pipe or tube thickness is over 7 mm, the specimen thickness shall be reduced to 5 mm by machining material in excess on the opposite side from that (those) in contact with the process fluid. 如果管子厚度超过7mm,试件厚度应在材料与工艺流体接触面的背面进行加工,减薄至5mm。查看更多