ASME B18.2.6M:2012 pdf download

ASME B18.2.6M:2012 pdf download.Metric Fasteners for Use in Structural Applications
1 INTRODUCTION
1.1 Scope 1.1.1 This Standard covers the complete general and dimensional data for products in the metric series recognized as AmericanNationalStandard forsizes M12 through M36. These four metric structural products include (a) metric heavy hex structural bolts: ASTM A325M and ASTM A490M (b) metric heavy hex nuts: ASTM A563M (c) metric hardened steel washers; circular, circular clipped, and beveled: ASTM F436M (d) metric compressible washer-type direct tension indicators: ASTM F959M 1.1.2 The inclusion of dimensional data in this Standard is not intended to imply that all products described herein are stock production sizes. Consumers should consult with suppliers concerning lists of avail- able stock production sizes. 1.2 Dimensions All dimensions in this Standard are in millimeters, unless stated otherwise, and apply to unplated or uncoated product. When plating or coating is specified, the finished product dimensions shall be as agreed upon between supplier and purchaser. Symbols specifying geometric characteristics are in accordance with ASME Y14.5.
2 METRIC HEAVY HEX STRUCTURAL BOLTS: ASTM A325M AND ASTM A490M
2.1 Metric Heavy Hex Structural Bolt Dimensions Bolts shall conform to the dimensions given in Table 1. 2.1.1 Top of Head. The top of the head shall be full form and chamfered or rounded with the diameter of the chamfer circle, or start of rounding being equal to the maximum width across flats within a tolerance of −15% of the maximum across flats dimension. 2.1.2 Width Across Flats. The width across flats of heads shall be the distance measured perpendicular to the axis of product, overall between two opposite sides of the head. 2.1.3 Head Taper. The maximum width across flats shall not be exceeded. No transverse section through the head between 25% and 75% of actual head height, as measured from the bearing surface, shall be less than the minimum width across flats. 2.1.4 Head Height. The head height shall be that overall distance measured parallel to the axis of the product from the top of the head to the bearing surface and shall include the thickness of the washer face. The raised grade and the manufacturer’s identification are excluded from the head height. 2.1.5 Position of Head. The runout of the flats of the head shall be no greater than 6% of the maximum width across flats. For referee purposes, the evaluation shall be made by indicating on the flats while holding the body one bolt diameter from under the head and rotating the part. 2.1.6 Bearing Surface. Bearing surface shall be flat and washer faced. However, a die seam across the bear- ing face shall be permissible. The diameter of the washer face shall be equal to the maximum width across the flats with a minus tolerance of 10%. The thickness of the washerfaceshallbe notless than0.04mmnorgreater than 0.08 mm. The plane of the bearing surface shall be perpendicular to the axis of the body within the FIM limits specified for total runout. The measurement of FIM shall extend as close to the periphery of the bearing surface as possible while the bolt is being held in a collet or other gripping device at a distance of one bolt diameter from the underside of the head. The angularity measurement shall be taken at a location to avoid inter- ference from a die seam. 2.1.7 Body Diameter. The body diameter limits are shown in Table 1. Any swell or fin under the head or any die seam on the body shall not exceed the basic bolt diameter by the following (a) 1.25 mm for M12 and M16 (b) 1.5 mm for M20 through M30 (c) 2.30 mm for M36 2.1.8 Bolt Length. The bolt length shall be the dis- tance measured parallel to the axis of the product from the bearing surface of the head to the extreme end of the bolt including point. Bolts are normally furnished in 5 mm length increments through 100 mm and 10 mm increments over 100 mm.