When bolt size are M30 and over, metric fine screw threads of 3 mm pitch series shall be used.

如果螺栓尺寸为m 30或以上，公制螺纹螺旋间距应为3mm。

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When bolt size are M30 and over, metric fine screw threads of 3 mm pitch series shall be used.

如果螺栓尺寸为m 30或以上，公制螺纹螺旋间距应为3mm。

youdao