ASME B18.2.2:2022 pdf free download.Nuts for General Applications: Machine Screw Nuts; and Hex,Square,Hex Flange,and Coupling Nuts(Inch Series).
3 GENERAL DATA
3.1 Width Across flats
The width at-ross flats of nut shall be the overall distance measured. perpendicular to the axis of nut. between two opposite sides of the nut in accordance with the notes on respective dimensional tables.
Maximum width across flats shall not be exceeded, except as stated below. No transverse section through the nut between 25% and 75% of the actual nut thickness as measured from the bearing surface shall be less than the minimum width across flats,
NOTE: Nonferrous milled-from-bar hex nuts: The minimum across flats dimensiossa olnonferrous inllled-Irom-bar hex nuts shall not be less than the values tabuLated in Tables 1.1.1-1 through 1.1.1-15. The maximum across flats size may be greater than the tabulated values in Tables 111-1 through 1.1.1-IS but shall not be equal to or greater than the minimum wrench opening shown in Nonnuindatory Appendix B, Table Il-I.
3.2 Corner flU
A rounding or lack of fill at junction of hex corners with chamfer shall be permissible, provided the width across corners Is within specified limits at and beyond a distance equal to 17.5% of the basic thread diameter from the chamfered face.
3.3 Tops of Nuts and Chamfers
Tops of nuts shall be flat and chamfered, except castle nuts where chamfer is optional. Unless otherwise specified by the purchaser or in this Standard, nuts of nominal size % in. and smaller shall be double-chamfered. Larger size nuts shall be double-chamfered or have washer-faced bearing surface and chamfered top,
3.3.1 SingLe-Chamfered Nuts and Washer-Faced Nuts. Diameter of the chamfer cirde shall be equal to the maximum width across flats within a tolerance of—15%. The length of chamfer at hex corners shall be from 5% to 15% of the basic thread diameter. The surface of the chamfer may be slightly convex or rounded.
3.3.2 DoubLe-Chamfered Nuts. Diameter of the chamfer circle shall be equal to the maximum width across flats with a —10% tolerance.
3.4 Countersink
Unless otherwise specifIed in this Standard, tapped holes shall be countersunk on the bearing faces, The maximum countersink diameter shall be the thread basic (nominal) major diameter plus 0.030 In. for nuts of nominal size In. and smaller, and 1.08 times the basic major diameter for nuts larger than 34 In. No part of the threaded portion shall project beyond the bearing surface.
3.5 Nut Thickness
The nut thickness shall he the overall distance, measured parallel to the axis olnut, from the top of the nut to the bearing surface and shall include the thickness of the washer face where provided.
3.6 Washer Face Diameter
Unless otherwise specified, the outside diameter of washer face shall be equal to the maximum width across flats with a — 10% tolerance.
3.7 SLots
When specified In (hr respective dimensional table, slots shall be normal to nut flats, The contour of the bottom of slots shall be at manufacturer’s option. Requirements (or gaging slots are specifIed in Mandatory Appendix I.
ASME B18.2.2:2022 pdf free download
