ASME B18.2.1-2012 (R2021)

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.