ASME B18.2.1:2010 pdf free download.Square, Hex, Heavy Hex, and Askew Head Bolts and Hex, Heavy Hex, Hex Flange, Lobed Head, and Lag Screws (Inch Series).
2 GENERAL DATA FOR BOTH BOLTS AND SCREWS
2.1 Heads
2.1.1 Top of Head. Top of head shall be full form and chamfered, with thcdiamcterofchamfercircleequal to the masimum width across fiats, on square or hex head produce and the ‘B dimension shown in Table 11 for lobed head screws with a tolerance of —15%.
2.1.2 Width Across Flats. The width across flats of head shall be the overall distance measured perpendicular to the axis of product between two opposite sides of the head in accordance with the notes in respective dimensional tables.
2.1.3 Head Height. The head height shall be the oserall distance measured parallel to the axis of pnuct from the top of the head to the bearing surface and shall include the thickness of the washer face where provided.
2.1.4 Position of Head. The runout of the flats or lobes of the head shall be no greater than 6. of the maximum width across flats or lobes. For reference purposes, the evaluation shall be made by indicating on the flats or outer surface of lobes while holding the body one bolt diameter from under the head and rotating the part.
2.2 Bolt or Screw Length
The bolt or screw length shall be the distance measured parallel to th axis of product froni the bearing surface of the head to the extreme end of the bolt or screw, including the point if the product is pointed.
2.3 Body Diameter
The bod’ diameter minimum/maximum limits are defined in each of the respective applicable tables. Unless otherwise specified by the purchaser, the body stle supplied shall be full-size body.
NCYrES:
(I) Only bolts and lag ecrews .ire permitted to have die seams eu their body thai exceed the body diameter. Die seams on the body and afl otlw styIe of screws that exceed the body diameter aie floe pvnmtted.
(2) For recommended clearance of hole sizes for bolts arid screws, refer to ASME Bl&2..
2.4 Points
Unless otherwise specified, bolts need not be pointed. l’roducts designated as screws, with the exception of lag screws, are required to have a chamfered point. The chamfer angle may vary depending on the manufacturing process. When specified. the chamfer angle should be considered a reference dimension only. The presence of a point is to reduce the possibility of damage to the leading threads and promote assembleahility with a tapped hole or nut. Point features not defined in a given product standard are at the discretion of the manufacturer.
ASME B18.2.1:2010 pdf free download
