ASME B18.5.2.1M-2006 pdf download

ASME B18.5.2.1M-2006 pdf pdf download.Metric Round Head Short Square Neck Bolts.
1 INTRODUCTORY NOTES 1.1 Scope 1.1.1 This Standard covers the general and dimen- sional data for metric series round head short square neckbolts recognized as anAmerican National Standard and intended primarily for applications in thin metals. 1.1.2 The inclusion of dimensional data in this Standard is notintended to imply thatall sizes described are production stock items. Consumers should consult with suppliers concerning lists of stock production items. 1.2 Comparison With ISO 8678:1988 1.2.1 Steel bolts produced to this Standard are functionally interchangeable with bolts which conform to ISO 8678:1988. Differences between this Standard and ISO 8678 are: size M14, materials other than steel, and minor variations in tolerances, such as, permissible swell, fin, or die seam on the body of bolts with nominal lengths longer than 150 mm. Dimensional require- ments in addition to, or different from ISO 8678, are shown in bold type in this Standard. 1.2.2 Letter symbols designating dimensional characteristics are in accordance with ISO 225 and ISO 8678, except where capitals have been used instead of the lowercase letters used in the ISO standards. 1.3 Terminology Fordefinitions ofterms relatingto fasteners or compo- nent features used in this Standard, refer to ASME B18.12. 1.4 Dimensions 1.4.1 All dimensions in this Standard are in milli- meters (mm), and apply to unplated or uncoated prod- uct, unless stated otherwise. 1.4.2 Symbols specifying geometric characteristics are in accordance with ASME Y14.5M. 1.5 Clearance Holes The recommended sizes of clearance holes in materi- als to be assembled, using round head short square neck bolts, are given in Nonmandatory Appendix B.
1.6 Designation 1.6.1 Roundheadshortsquareneckbolts are desig- nated by the following data, preferably in the sequence shown: product name and designation of the standard, nominal diameter and thread pitch, nominal length, steel property class or material identification, and pro- tective coating, if required. EXAMPLES: Round head short square neck bolt B18.5.2.1M, M10 ? 1.5 ? 50 − 9.8 -zinc plated perASTMF 1941MFe/Zn5C. Round head short square neck bolt B18.5.2.1.M, M6 ? 1 ? 35, stainless steel class C1-50 ASTM F 738M. NOTE: It is common practice in ISO standards to omit thread pitchfromproductsizedesignations whenscrew threadsare metric coarse thread series (e.g., M10 is M10 ? 1.5). 1.6.2 For the recommended part number (PIN) system for metric round head short square neck bolts, see ASME B18.24. 1.7 Referenced Standards Unless otherwise specified, the standards referenced shall be the most recent issue at the time of order place- ment. The following is a list of publications referenced in this Standard. ASME B1.3M, Screw Thread Gaging Systems for Dimensional Acceptability — Inch and Metric Screw Threads (UN, UNR, UNJ, M, and MJ) ASME B1.13M, Metric Screw Threads — M Profile ASME B18.2.8, Clearance Holes for Bolts, Screws, and Studs ASME B18.12, Glossary of Terms for Mechanical Fasteners ASME B18.18.1M, Inspection and Quality Assurance for General Purpose Fasteners ASME B18.18.2M, Inspection and Quality Assurance for High-Volume Machine Assembly Fasteners ASME B18.18.3M, Inspection and Quality Assurance for Special Purpose Fasteners ASME B18.18.4M, Inspection and Quality Assurance for Fasteners for Highly Specialized Engineered Applica- tions — Metric ASME B18.24, Part Identifying Number (PIN) Code System Standard for B18 Fastener Products
2.2 Square Neck 2.2.1 Depth of Neck. The depth of the square neck is the distance, measured parallel to the axis, from the bearing surface to the plane where the corner chamfer would intersect the nominal bolt diameter. 2.2.2 Corner Depth. The corner depth is the dis- tance, measured at a corner of the square, from the plane of the bearing surface to the last plane at which the width across corners, E, is within its specified limits. 2.2.3 Width Across Corners. The corners of the square neck may be rounded or underfilled to the extent allowed by the minimum width across corners, E, and the minimum corner depth, F 1 . There may be a fin or die seam on the corners of the square not to exceed the maximum width across corners. 2.3 Fillets The radius of fillets at the junction of head and square neck and at the junction of square neck and shank shall be within the specified limits, except for bolts produced from nonferrous and corrosion resistance materials, on which maximum fillets shall be subject to agreement between manufacturer and purchaser.