1.1 This specification establishes allowable limits for thevarious types of surface discontinuities that may occur during themanufacture and processing of bolts, screws, and studs, includingheat-treated machine screws, tapping screws, and sems (the washersof screw-washer assemblies are excluded). This specification coversmetric series products with nominal diameters of 4 mm and largerand with specified minimum tensile strengths of 420 MPa and higher;and inch series products with nominal diameters of No. 5 (0.1250in.) and larger and with specified minimum tensile strengths of 60000 psi and higher.
1.2 When the engineering requirements of the applicationnecessitate control of surface discontinuities on bolts, screws, orstuds, the purchaser shall specify conformance to ASTMSpecification F 788/F 788M, in the original inquiry and purchaseorder.
1.2.1 When the engineering requirements of the applicationnecessitate that surface discontinuities on bolts, screws, andstuds be controlled within limits closer than those specified inthis specification, the purchaser shall specify the applicablelimits in the original inquiry and purchase order.
1.3 The allowable limits established in this specification formetric bolts, screws, and studs with nominal diameters from 4 to 24mm inclusive, are essentially identical with requirements given inISO 6157/I. There are no ISO standards for surface discontinuitieson any inch-series products.
1.4 The values stated in either SI (metric) or inch-pound unitsare to be regarded separately as standard. The values stated ineach system are not exact equivalents, therefore, each system mustbe used independently of the other. Combining values from the twosystems may result in nonconformance with the specification.