ASME B18.5-2008 pdf – Round Head Bolts(Inch Series)
ASME B18.5-2008 pdf – Round Head Bolts(Inch Series).
2.1.3 Undertiead Fillets. All bolts having flat bearing surface type heads shall have a definite fillet at the junction of head and shank. The minimum radius of fillet shall be equal to one-half of the maximum values specified in the respective dimensional tables, The radius of Fillet shall not exceed the values specified in the respective dimensional tables except for bolts produced From nonferrous and corrosion-resistant materials. on which maximum fillets shall be subject to agreement between manufacturer and purchaser.
2.2 Square Neck
2.2.1 Depth of Square. The depth of square shall be measured, paraLlel to the axis of bolt at the midpoint of the flats of square, from the bottom of square to the bea ring surface fur bolts having flat bearing surface type heads, and to the intersection of flats of square with the conical bearing surface for bolts having countersunk heads.
2.2.2 Corners ol Square. The corners of square neck ma be rounded to the extent specified in the respective dimensional tables and need not be filled out for the total depth of square.
2.3 Body Diameter
2.3.1 FuLl Diameter Body. Unless otherwise specilied, all bolts covered by this Standard, except round head square neck bolts and round head short square neck bolts, will be furnished with full diameter body of limits given in the dimensional tables.
2.3.2 Round Head Square Neck and Round Head Short Square Neck Bolt Diameter Body. Unless otherwise specified, round head square neck bolts and round head short squaw neck bolts shall be furnished with a body diameter having a maximum limit equal to that of the full diameter body and a minimum limit equal to the minimum pitch diameter of the thread as given in the dimensional tables.
2.3.3 SweLl or Fin. A swell or fin under the head or under corners of squaw neck shall be permissible. provided it dues not affect serviceability, nor exceed the basic bolt diameter by more than the following:
(a) 0.030 in. for sizes up to and including 4 in.
(k) 0.050 In. for sizes over !‘ In. to 3 in., Inclusive
(c) 0.063 in. for sizes over 3/4 in. to 1 in. inclusive
(d) 0.093 in. for sizes over l4 in.
Bolts of nominal lengths too short to accommodate the minimum thread lengths shall be threaded for full length. The length from the head or neck to the first complete (full form) thread shall not exceed the length of 21/2 threads for sizes up to and including 1 in., and 31/ threads for sizes over I in.
Bolts need not be pointed.
2.8 Materials and Mechanical Properties
2.8.1 Steel. Unless otherwise specified, chemical and mechanical properties of steel bolts, except step bolts and elevator bolts, shall conform to Grade A of ASTM A 307, and shall be stress relieved as required by the Standard. Due to peculiarities of the head configurations, steel step bolts and elevator bolts are considered conforming if the tensile strength in pounds is equal to or greater than the values indicated in the applicable material standard.
2.8.2 Other Materials. Nonferrous materials are covered in ASTM F 468. Corrosion-resistant steels are covered in ASTM F 593.
2.9 Identification Symbols
2.9.1 Grade Symbols. Each of the products included in this Standard shall be marked in accordance with the requirements of the applicable specification for its chemistry and mechanical properties.
2.9.2 Source Symbols. Each of the products included in this Standard shall be marked to identify the source accepting responsibility for the conformance of the bolt to this and other applicable specifications.
Unless otherwise specified, round head bolts shall be supplied with natural (as processed) finish, unpiated or uncoa ted.
Bolts shall be free from surface imperfections such as burrs, seams, laps, loose scale, and other surface irregularities that could affect serviceability.
When engineering requirements of the application require control of surface discontinuities, the purchaser shall specify conformance to ASTM F 788/F 788M in the original inquiry and purchase order.