ASME B18.2.3.2 pdf download

ASME B18.2.3.2 pdf download Metric Formed Hex Screws
6.6.5 Position of Body-to-Thread.
For products with cut threads, at maximum material condition, the axis of the screw body, D s (derived median line), over a length equal to the nominal screw diameter from the last scratch of thread, shall be within the positional tol- erance zone diameter specified in Table 2 with respect to the axis of the thread, over a length equal to the nom- inal screw diameter from the last complete thread. A gage and gaging procedure for checking body position is given in Nonmandatory Appendix B.
6.7 Screw Threads
6.7.1 Thread Series and Tolerance Class. Screw threads shall be general purpose metric screw threads with tolerance Class 6g conforming to ASME B1.13M, unless otherwise specified by the purchaser. For screws with additive finish, size limits for tolerance Class 6g apply prior to coating, and the thread after coating is subject to acceptance using a basic (toler- ance position h) size GO thread gage and tolerance Class 6g thread gage for either minimum material LO or NOT GO.
6.7.2 Thread Gaging. Unless otherwise specified, dimensional acceptability of screw threads shall be based on System 21 of ASME B1.3M. 6.8 Materials and Mechanical Properties
6.8.1 Steel. Unless otherwise specified, steel screws shall conform to the requirements of ASTM F 568M.
6.8.2 Corrosion-Resistant Steels. Unless other- wise specified, screws made of corrosion-resistant steels shall conform to the requirements of ASTM F 738M.
6.8.3 Nonferrous Metals. Unless otherwise speci- fied, nonferrous screws shall conform to the requirements of ASTM F 468M. 6.9 Finish Unless otherwise specified, screws shall be supplied with a natural (as processed) finish, unplated or un- coated, in a clean condition and lightly oiled.
6.10 Identification Symbols Identification marking symbols shall be on top of the screw heads and shall be raised or indented at the man- ufacturer’s option, unless otherwise specified at the time of ordering. Marking shall be legible to the unaided eye with the exception of corrective lenses. When raised, markings shall project not less than 0.1 mm for M14 and smaller screws, and 0.3 mm for M16 and larger screws above the surface of the head, and the total head height (head plus markings) shall not exceed the specified max- imum head height plus 0.1 mm for M5 and M6 screws, 0.2 mm for M8 and M10 screws, 0.3 mm for M12 and M14 screws, and 0.4 mm for M16 and larger screws. When indented, the depth of the marking shall not re- duce the load carrying capability of the screw.
6.10.1 Property Class Symbols. Each screw shall be marked in accordance with the applicable specifica- tion for its chemical and mechanical requirements.
6.10.2 Source Symbols. Each screw shall be marked to identify its source (manufacturer or private label distributor). 6.11 Workmanship Screws shall be free from surface imperfections such as burrs, seams, laps, loose scale, or other irregularities that could affect serviceability. When control of surface discontinuities is required, the purchaser shall specify conformance to ASTM F 788/F 788M.
6.12 Inspection and Quality Assurance Unless otherwise specified, acceptability of screws shall be determined in accordance with ASME B18.18.1.
6.13 Dimensional Conformance Products shall conform to the specified dimensions.
(a) Unless otherwise specified, the following provi- sions shall apply for inspection of dimensional charac- teristics. The designated characteristics are defined within the following table and shall be inspected in accordance with ASME B18.18.2 to the inspection level shown.