BS 6322-3:1982 紧固件公差 螺纹直径从 1 毫米到 150 毫米（含）的公制螺栓、螺钉和螺母垫圈公差规范 产品等级 A 和 C
Tolerances for fasteners.-Specification for tolerances of washers for metric bolts, screws and nuts with thread diameters from 1 mm up to and including 150 mm. Product grades A and C