本标准涵盖八种英制系列方形和六角螺栓和螺钉的完整通用和尺寸数据。附件还包括螺纹跳动套筒规、检查螺栓和螺钉直线度的测量程序、钢螺栓和螺钉的等级标记、尺寸数据所依据的公式，以及有助于将产品识别为螺钉或螺栓的规范。然而，应当理解，如果出现与产品验收有关的问题，应以表格中的尺寸为准，而不是通过公式进行重新计算。重型六角结构螺栓，以前包含在ANSI B18中。2.1，现在已包含在ASME B18中。2.6.

This Standard covers the complete general and dimensional data for eight product types of inch series square and hex bolts and screws. Also included are appendices covering thread runout sleeve gages, gaging procedure for checking bolt and screw straightness, grade markings for steel bolts and screws, formulas on which dimensional data are based, and a specification to assist in identifying a product as being a screw or a bolt. It should be understood, however, that where questions arise concerning acceptance of product, the dimensions in the tables shall govern over recalculation by formula. Heavy hex structural bolts, formerly covered in ANSI B18.2.1, are now covered in ASME B18.2.6.