我们用检测规来检查螺纹对位问题？？可老外的意思让我模糊，求解！！
在加拿大 In order to find the problem and try to locate it: could you check 30 valves which are in the tolerance of +/-6° (checked by your gauge). These valves should be marked with a identification, in order to know which production batch it comes...华人论坛