Asme B 18.2.2

+7 (495) 133-39-24
INMOTEH.RU
ТРУБЫ, ФЛАНЦЫ,
КРЕПЕЖ, ДЕТАЛИ
ТРУБОПРОВОДА
ПО МЕЖДУНАРОДНЫМ
СТАНДАРТАМ:
ASME, DIN, NF, UNI, EN, JIS И ДР.
INMOTEH.RU
ДАННЫЙ МАТЕРИАЛ ПРЕДОСТАВЛЕН ИСКЛЮЧИТЕЛЬНО ДЛЯ ОЗНАКОМЛЕНИЯ

ASME B18.2.2-2010
[Revision of ASME/ANSI B18.2.2-1987 (R2005)]
Nuts for General

Applications: Machine
Screw Nuts, Hex,
Square, Hex Flange,
and Coupling Nuts
(Inch Series)
A N A M E R I C A N N AT I O N A L STA N DA R D
INTENTIONALLY LEFT BLANK
ASME B18.2.2-2010
[Revision of ASME/ANSI B18.2.2-1987 (R2005)]
Nuts for General

Applications: Machine
Screw Nuts, Hex,
Square, Hex Flange,
and Coupling Nuts
(Inch Series)
A N A M E R I C A N N AT I O N A L S TA N D A R D
Three Park Avenue • New York, NY • 10016 USA

Date of Issuance: November 30, 2010
This Standard will be revised when the Society approves the issuance of a new edition. There will
be no addenda issued to this edition.
ASME issues written replies to inquiries concerning interpretations of technical aspects of this
Standard. Periodically certain actions of the ASME B18 Committee may be published as Cases. Cases
and interpretations are published on the ASME Web site under the Committee Pages at
http://cstools.asme.org as they are issued.
ASME is the registered trademark of The American Society of Mechanical Engineers.
This code or standard was developed under procedures accredited as meeting the criteria for American National
Standards. The Standards Committee that approved the code or standard was balanced to assure that individuals from
competent and concerned interests have had an opportunity to participate. The proposed code or standard was made
available for public review and comment that provides an opportunity for additional public input from industry, academia,
regulatory agencies, and the public-at-large.
ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.
ASME does not take any position with respect to the validity of any patent rights asserted in connection with any
items mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability for
infringement of any applicable letters patent, nor assumes any such liability. Users of a code or standard are expressly
advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is
entirely their own responsibility.
Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted as
government or industry endorsement of this code or standard.
ASME accepts responsibility for only those interpretations of this document issued in accordance with the established
ASME procedures and policies, which precludes the issuance of interpretations by individuals.
No part of this document may be reproduced in any form,

in an electronic retrieval system or otherwise,
without the prior written permission of the publisher.
The American Society of Mechanical Engineers

Three Park Avenue, New York, NY 10016-5990
Copyright © 2010 by
THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
All rights reserved
Printed in U.S.A.
CONTENTS
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Committee Roster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Correspondence With the B18 Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
3 General Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Tables
1-1 Dimensions of Square and Hex Machine Screw Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1-2 Dimensions of Small Pattern Hex Machine Screw Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Dimensions of Square Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Dimensions of Hex Flat Nuts and Hex Flat Jam Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 Dimensions of Hex Nuts and Hex Jam Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5 Dimensions of Hex Slotted Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6 Dimensions of Hex Thick Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7 Dimensions of Hex Thick Slotted Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
8 Dimensions of Heavy Square Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9 Dimensions of Heavy Hex Flat Nuts and Heavy Hex Flat Jam Nuts . . . . . . . . . . . . . . . 13
10 Dimensions of Heavy Hex Nuts and Heavy Hex Jam Nuts . . . . . . . . . . . . . . . . . . . . . . . . 14
11 Dimensions of Heavy Hex Slotted Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
12 Dimensions of Hex Flange Nuts and Large Hex Flange Nuts . . . . . . . . . . . . . . . . . . . . . . 16
13 Dimensions of Hex Coupling Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Mandatory Appendix
I Slot Gages and Gaging for Slotted Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Nonmandatory Appendices
A Formulas for Nut Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
B Wrench Openings for Square and Hex Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
iii
FOREWORD
American National Standards Committee B18 for the standardization of bolts, screws, nuts,
rivets, and similar fasteners was organized in March 1922 as Sectional Committee B18 under
the aegis of the American Engineering Standards Committee (later the American Standards
Association, then the United States of America Standards Institute, Inc.) with the Society of
Automotive Engineers and the American Society of Mechanical Engineers as joint sponsors.
Subcommittee 2 was subsequently established and charged with the responsibility for technical
content of standards covering wrench head bolts and nuts.
Subcommittee 2, after appraisal of the requirements of industry, developed a proposed standard
series of bolt head and nut dimensions. This proposal was finally approved and designated a
Tentative American Standard in February 1927.
A first revision of the document was designated as an American Standard in March 1933 and
was followed by a second revision that was granted approval as an American Standard in
January 1941.
Following reorganization of the B18 Committee in 1947, Subcommittee 2 was asked to expand
the standard on head proportions into a complete product standard. A proposal covering square
and hexagon head bolts and nuts, hexagon head cap screws, and automotive hexagon head bolts
was prepared and submitted to the B18 Committee in April 1950. While this draft was under
consideration, the B18 Committee received a proposal from the British Standards Institution
for unification of dimensions on products incorporating unified screw threads. The Committee
welcomed the opportunity of discussing the proposals and an American-British-Canadian
Conference was held in New York on June 1 and 2, 1950.
It was agreed in the conference that the essentials of unification could be accomplished by
selection of mutually satisfactory across-the-flats dimensions, since this would permit the use of
the same wrenches and because other features would rarely affect interchangeability. After due
consideration, suitable existing across-the-flats dimensions were selected for the hexagon products
affected.
In its meeting of October 13, 1950, Subcommittee 2 agreed to incorporate into the proposed
standard the conference recommendations on 1⁄4 in. hexagon head bolts, 5⁄8 in. hexagon head cap
screws and automotive hexagon head bolts, and 7⁄16 in. light and regular hexagon and square
nuts. At a subsequent meeting of Subcommittee 2, further changes were adopted in order to
combine the light and regular series of nuts, and to combine the automotive hexagon head bolt,
hexagon head cap screw, and regular hexagon head close tolerance bolt.
In view of the progress made in the United States and the urgency of standardization for
mutual defense, the British Standards Institution sponsored a second conference in London in
April 1951 to complete the unification of certain hexagon bolts and nuts.
At a meeting on June 8, 1951, Subcommittee 2 reaffirmed its acceptance of the unified dimensions
that correspond with those in the March 1951 draft, but attempted to select better nomenclature
for the unified products. A final draft incorporating the nomenclature “Finished Hexagon Bolts
and Nuts” and containing numerous editorial changes was submitted for letter ballot in September
1951. Following approval by the B18 Committee and the sponsors, the proposal was presented
to the American Standards Association for approval and designation as an American Standard.
This was granted on March 24, 1952.
It was recognized that the standard was in need of additional refinements, therefore
Subcommittee 2 began work immediately to eliminate these shortcomings. A proposed revision
removing inconsistencies with respect to fillets, improving the length tolerances on heavy hexagon
bolts, and incorporating numerous other corrections and clarifications of an editorial nature
resulted. The most noteworthy editorial change was a decision to combine the coverage for
hexagon cap screws and square head set screws from the B18.2 standard with the coverage for
slotted head cap screws and slotted headless set screws from the B18.6 standard for publication
in a separate document. The requirements for the unified hexagon cap screws and finished
iv
hexagon bolts being identical in the overlapping sizes, the data would now be available in two
publications. Following approvals by the B18 Committee and sponsor organizations, the proposal
was submitted to the American Standards Association and declared an American Standard on
February 2, 1955.
A revision of this Standard comprised of numerous editorial corrections and inclusion of an
appendix for grade markings was duly approved and designated an American Standard on
April 18, 1960.
At a meeting in February 1960, Subcommittee 2 approved a recommendation to reduce the head
heights for heavy, heavy semifinished, and heavy finished hexagon bolt, which was subsequently
approved by letter ballot of the B18 Committee on August 16, 1960. A proposed standard for
heavy hexagon structural bolts submitted and accepted by Subcommittee 2 at its October 17,
1960 meeting was approved by letter ballot of the B18 Committee on May 9, 1961. To meet the
urgent needs of the steel construction industry, it was considered necessary to publish the standard
for the structural bolts immediately. Consequently, Appendix IV to ASA B18.2-1960 containing
coverage for the revised heavy hexagon bolts and the new heavy hexagon structural bolts was
released in 1962.
In October 1961, Subcommittee 2 appointed a subgroup to review all product standards for
square and hexagon bolts, screws, and nuts, and to recommend simplifications that would be
compatible with technical, production, and distribution advances that had occurred over the prior
several years. The subgroup presented its recommendations at a meeting of Subcommittee 2 in
October 1962. It was agreed that the internally and externally threaded products should be
published in separate documents as suggested, and draft proposals for each were completed.
The proposed revision for square and hex nuts incorporated the following subgroup recommen-
dations: discontinuation of regular semifinished nuts; elimination of regular hexagon and heavy
hexagon nuts in sizes 1⁄4 in. through 1 in.; elimination of finished hexagon nuts in sizes larger
than 11⁄2 in.; elimination of the washer face semifinished style on finished series nuts in sizes
5
⁄8 in. and smaller and heavy series nuts in sizes 7⁄16 in. and smaller; removal of machine screw
nuts (these nuts are now contained in B18.6.3); and adoption of an abbreviated product nomencla-
ture. Letter ballot of this proposal to the B18 Committee resulted in approval. Following acceptance
by the sponsor organizations the revision was submitted to the American Standards Association
and designated ASA B18.2.2 on September 8, 1965.
Subcommittee 2 continued to further develop refinements initiated by the simplification sub-
group and to study changes suggested by consumer interests. This work culminated in Subcom-
mittee acceptance of a 1970 proposal incorporating, in addition to numerous editorial changes,
revisions to the requirements on angularity of bearing face and countersink diameters for the
various hex nuts and heavy hex nuts, and inclusion of an appendix covering the gaging of slots
in slotted nuts.
The proposed revision, after approval by letter ballot of the B18 Committee in March 1970,
was subsequently approved by the sponsors and submitted to the American National Standards
Institute for designation as an American National Standard. This was granted on January 18, 1972.
A proposed revision of this Standard agreed upon by Subcommittee 2 incorporated a provision
to enable consumers to specify heavy hex nuts and heavy hex jam nuts with close bearing face
angularity, when required; clarified intent with regard to width across flats on nuts produced
from bar stock; deleted coverage for hex castle nuts from the appendices; and included numerous
editorial refinements. This proposal was formally approved by letter ballot of the subcommittee
and the B18 Committee. Following its acceptance by the sponsor organizations the revision was
referred to the American National Standards Institute and granted approval as an American
National Standard on February 27, 1987.
In March 2009 the B18.2 Subcommittee undertook a revision of this Standard. The format has
been updated to meet the requirements of ASME B18.12.1. Regular pattern machine screw nuts
have been moved from ASME B18.6.3, and the small pattern machine screw nuts have been
added to this Standard. The hex flange nut that was previously referred to as IFI-145 has been
added. Coupling nuts have been added. Many of the sizes came from the IFI-128 and others
were based on what has been used for many years by industry. This proposal was formally
approved by letter ballot of the subcommittee and the B18 Committee. Following its acceptance
by the sponsor organizations, the revision was referred to the American National Standards
Institute and granted approval as an American National Standard on August 24, 2010.
v
ASME B18 COMMITTEE
Standardization of Bolts, Nuts, Rivets, Screws,
Washers, and Similar Fasteners
(The following is the roster of the Committee at the time of approval of this Standard.)
STANDARDS COMMITTEE OFFICERS

J. Greenslade, Chair
D. S. George, Vice Chair
R. D. Strong, Vice Chair
C. J. Gomez, Secretary
STANDARDS COMMITTEE PERSONNEL

V. Cartina, Autocraft Industrial W. H. Kopke, Consultant
D. A. Clever, Consultant W. J. Lutkus, Emhart Technologies
P. Cockman, Ford Motor Co. D. McCrindle, Canadian Fasteners Institute
C. A. Dugal de la Garza, TSP, Inc. M. D. Prasad, Contributing Member, Global M&F Solutions, Inc.
D. S. George, ND Industries S. Savoji, ITW Medalist
C. J. Gomez, The American Society of Mechanical Engineers W. Schevey, Contributing Member, BGM Fastener Co., Inc.
Q. M. Smith III, Oregon Department of Transportation
J. Greenslade, Industrial Fasteners Institute
W. R. Stevens, Ramco Specialties, Inc.
J. J. Grey, Contributing Member, Fastener Consulting Services, Inc.
R. D. Strong, Consultant
B. Hasiuk, Contributing Member, Defense Supply Center S. W. Vass, Consultant
Philadelphia C. B. Wackrow, MNP Corp.
A. Herskovitz, Consultant W. K. Wilcox, Consultant
J. Hubbard, Leland-Powell Fasteners, Inc. C. B. Williamson, Fastenal Co.
J. Jennings, Contributing Member, Naval Surface Warfare Center C. J. Wilson, Consultant
W. H. King, Porteous Fastener Co. R. B. Wright, Contributing Member, Wright Tool Co.
J. F. Koehl, Contributing Member, Spirol International Corp. J. G. Zeratsky, National Rivet and Manufacturing Co.
SUBCOMMITTEE 16 — NUTS
W. R. Stevens, Chair, Ramco Specialties, Inc. J. Jennings, Naval Surface Warfare Center
V. Cartina, Vice Chair, Consultant J. F. McCarrick, Defense Supply Center Philadelphia
A. P. Cockman, Ford Motor Co. W. L. Sakowski, Account Managers LLC
R. M. Serabin, Freundlich Supply Co.
B. A. Dusina, Federal Screw Works
D. F. Sharp, GMS Structural Engineers
M. A. Elmi, Caterpillar D. J. Soscia, Electric Boat Corp.
D. S. George, ND Industries W. K. Wilcox, Consultant
J. Greenslade, Industrial Fasteners Institute C. B. Williamson, Fastenal Co.
J. J. Grey, Fastener Consulting Services, Inc. C. J. Wilson, Consultant
vi
CORRESPONDENCE WITH THE B18 COMMITTEE
General. ASME Standards are developed and maintained with the intent to represent the
consensus of concerned interests. As such, users of this Standard may interact with the Committee
by requesting interpretations, proposing revisions, and attending Committee meetings. Corre-
spondence should be addressed to:
Secretary, B18 Standards Committee
The American Society of Mechanical Engineers
Three Park Avenue
New York, NY 10016-5990
http://go.asme.org/Inquiry
Proposing Revisions. Revisions are made periodically to the Standard to incorporate changes
that appear necessary or desirable, as demonstrated by the experience gained from the application
of the Standard. Approved revisions will be published periodically.
The Committee welcomes proposals for revisions to this Standard. Such proposals should be
as specific as possible, citing the paragraph number(s), the proposed wording, and a detailed
description of the reasons for the proposal, including any pertinent documentation.
Proposing a Case. Cases may be issued for the purpose of providing alternative rules when
justified, to permit early implementation of an approved revision when the need is urgent, or to
provide rules not covered by existing provisions. Cases are effective immediately upon ASME
approval and shall be posted on the ASME Committee Web page.
Requests for Cases shall provide a Statement of Need and Background Information. The request
should identify the standard, the paragraph, figure or table number(s), and be written as a
Question and Reply in the same format as existing Cases. Requests for Cases should also indicate
the applicable edition(s) of the standard to which the proposed Case applies.
Interpretations. Upon request, the B18 Standards Committee will render an interpretation of
any requirement of the Standard. Interpretations can only be rendered in response to a written
request sent to the Secretary of the B18 Standards Committee.
The request for an interpretation should be clear and unambiguous. It is further recommended
that the inquirer submit his/her request in the following format:
Subject: Cite the applicable paragraph number(s) and the topic of the inquiry.
Edition: Cite the applicable edition of the Standard for which the interpretation is
being requested.
Question: Phrase the question as a request for an interpretation of a specific requirement
suitable for general understanding and use, not as a request for an approval
of a proprietary design or situation. The inquirer may also include any plans
or drawings that are necessary to explain the question; however, they should
not contain proprietary names or information.
Requests that are not in this format may be rewritten in the appropriate format by the Committee
prior to being answered, which may inadvertently change the intent of the original request.
ASME procedures provide for reconsideration of any interpretation when or if additional
information that might affect an interpretation is available. Further, persons aggrieved by an
interpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME does not
“approve,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity.
Attending Committee Meetings. The B18 Standards Committee regularly holds meetings that
are open to the public. Persons wishing to attend any meeting should contact the Secretary of
the B18 Standards Committee.
vii
viii
ASME B18.2.2-2010
Nuts for General Applications: Machine Screw Nuts, Hex,

Square, Hex Flange, and Coupling Nuts (Inch Series)
1 INTRODUCTION ASME B18.12, Glossary of Terms for Mechanical

Fasteners
1.1 Scope
ASME B18.18.2, Inspection and Quality Assurance for
1.1.1 This Standard is intended to cover the com- High-Volume Machine Assembly Fasteners
plete general and dimensional data for the various types ASME B18.24, Part Identifying Number (PIN) Code
of inch series square and hex nuts, including machine System for B18 Fastener Products
screw nuts and coupling nuts, recognized as American ASME B107 Series, Standards for Hand Tools
National Standard. Also included are appendices cov- Publisher: The American Society of Mechanical
ering gaging of slots in slotted nuts, wrench openings Engineers (ASME) Three Park Avenue, New York, NY
for nuts, and formulas on which dimensional data are 10016-5990; Order Department: 22 Law Drive, P.O.
based. It should be understood, however, that where Box 2900, Fairfield, NJ 07007-2900 (www.asme.org)
questions arise concerning acceptance of product, the
dimensions in the tables shall govern over recalculation ASTM A 563, Standard Specification for Carbon and
by formula. Alloy Steel Nuts
ASTM F 467, Standard Specification for Nonferrous
1.1.2 The inclusion of dimensional data in this Nuts for General Use
Standard is not intended to imply that all of the products ASTM F 594, Standard Specification for Stainless Steel
described herein are stock production sizes. Consumers Nuts
are requested to consult with manufacturers concerning ASTM F 812/F 812M, Standard Specification for Surface
lists of stock production sizes. Discontinuities of Nuts, Inch and Metric Series
ASTM F 1941, Specification for Electrodeposited
1.2 Comparison to ISO Standards Coatings on Threaded Fasteners [Unified Inch Screw
There are no comparable ISO inch fastener standards. Threads (UN/UNR)]
Publisher: American Society for Testing and Materials
1.3 Dimensions (ASTM International), 100 Barr Harbor Drive, West
Unless otherwise indicated, units of measurement are Conshohocken, PA 19428 (www.astm.org)
expressed in inches.
SAE J995, Mechanical and Material Requirements for
1.4 Options Steel Nuts
Publisher: SAE International, 400 Commonwealth Drive,
Where options are allowed, they shall be selected at
Warrendale, PA 15096 (www.sae.org)
the manufacturer’s discretion unless otherwise specified
by the purchaser.
3 GENERAL DATA
1.5 Terminology References
3.1 Width Across Flats
For definitions of terminology not specifically defined
The width across flats of nut shall be the distance
in this Standard, refer to ASME B18.12.
measured, perpendicular to the axis of nut, overall
between two opposite sides of the nut in accordance
2 REFERENCES with the notes on respective dimensional tables.
Maximum width across flats shall not be exceeded,
Unless otherwise specified, the standards referenced
except as stated below. No transverse section through
shall be the latest edition at the time of order placement.
the nut between 25% and 75% of the actual nut thickness
ASME B1.1, Unified Inch Screw Threads (UN and UNR as measured from the bearing surface shall be less than
Thread Form) the minimum width across flats.
ASME B1.3, Screw Thread Gaging Systems for NOTE: Nonferrous milled-from-bar hex nuts: The minimum
Acceptability: Inch and Metric Screw Threads (UN, across flats dimensions of nonferrous milled-from-bar hex nuts
UNR, UNJ, M, and MJ) shall not be less than the values tabulated in Tables 1-1 through
1
ASME B18.2.2-2010
13. The maximum across flats size may be greater than the tabu- slots shall be at manufacturer’s option. Requirements
lated values in Tables 1-1 through 13, but shall not be equal to or for gaging slots are specified in Mandatory Appendix I.
greater than the minimum wrench opening shown in Table B-1,
Nonmandatory Appendix B.
3.8 True Position of Tapped Hole
3.2 Corner Fill 3.8.1 Hex Nuts. The axis of tapped hole in hex nuts
A rounding or lack of fill at junction of hex corners shall be located at true position with respect to the axis
with chamfer shall be permissible, provided the width of nut body within a tolerance zone having a diameter
across corners is within specified limits at and beyond equivalent to 4% of the maximum width across flats
a distance equal to 17.5% of the basic thread diameter for 11⁄2 in. nominal size nuts or smaller and 6% of the
from the chamfered face. maximum width across flats for nuts larger than 11⁄2 in.,
regardless of feature size.
3.3 Tops of Nuts and Chamfers
3.8.2 Square Nuts. The axis of tapped hole in square
Tops of nuts shall be flat and chamfered. Unless other- nuts shall be located at true position with respect to
wise specified by the purchaser or in this Standard, nuts the axis of nut body within a tolerance zone having a
in sizes 5⁄8 in. nominal size and smaller shall be double- diameter equivalent to 10% of the maximum width
chamfered. Larger size nuts shall be double-chamfered across flats, regardless of feature size.
or have washer-faced bearing surface and chamfered
top. 3.9 Bearing Surface Perpendicularity
3.3.1 Single-Chamfered Nuts. Diameter of the Bearing surface shall be flat and perpendicular to the
chamfer circle shall be equal to the maximum width axis of the threaded hole within the specified full indica-
across flats within a tolerance of −15%. The length of tor measurement (FIM) limit indicated in the tables.
chamfer at hex corners shall be from 5% to 15% of the
basic thread diameter. The surface of the chamfer may 3.10 Threads
be slightly convex or rounded. 3.10.1 Thread Class. Threads shall be Unified
3.3.2 Double-Chamfered Nuts and Washer-Faced Standard, Class 2B, of the series specified in the notes
Nuts. The diameter of chamfer circle on on respective dimensional tables, in accordance with
double-chamfered nuts and washer-faced nuts shall be ASME B1.1. Class 3B may be specified by the purchaser
within the limits of the maximum width across flats and if designated at the time of inquiry and order.
95% of the minimum width-across-flats. 3.10.2 Thread Gaging. Unless otherwise specified
by the purchaser, gaging for screw thread dimensional
3.4 Countersink
acceptability shall be in accordance with Gaging System
Unless otherwise specified in this Standard, tapped 21 as specified in ASME B1.3, Screw Thread Gaging
holes shall be countersunk on the bearing faces. The Systems for Dimensional Acceptability.
maximum countersink diameter shall be the thread basic
(nominal) major diameter plus 0.030 in. for 3⁄8 in. nominal 3.11 Material
size nuts and smaller, and 1.08 times the basic major Unless otherwise specified by the purchaser or else-
diameter for nuts larger than 3⁄8 in. No part of the where in this Standard, chemical and mechanical prop-
threaded portion shall project beyond the bearing erties of steel nuts shall conform to Grade A of
surface. ASTM A 563, Carbon and Alloy Steel Nuts or Grade 2
(square nuts only) of SAE J995. Nuts of other materials
3.5 Nut Thickness
such as corrosion resistant (stainless) steel, brass, bronze,
The nut thickness shall be the overall distance, mea- and aluminum alloys shall have properties as agreed
sured parallel to the axis of nut, from the top of the nut upon between the manufacturer and purchaser. Refer
to the bearing surface and shall include the thickness to ASTM F 594 for information on corrosion resistant
of the washer face where provided. alloy steel requirements and ASTM F 467 for information
on nonferrous materials.
3.6 Washer Face Diameter
Unless otherwise specified, the diameter of washer 3.12 Finish
face shall be within the limits of the maximum width Unless otherwise specified, nuts shall be supplied
across flats and 95% of the minimum width across flats. with a natural (as-processed) finish, unplated or
uncoated. If electroplated finishes are required, reference
3.7 Slots ASTM F 1941. Other finishes may be specified as indi-
When specified in the respective dimensional table, cated in the applicable mechanical and performance
slots shall be normal to nut flats. Contour of bottom of standards.
2
ASME B18.2.2-2010
3.13 Designation AEN24 and AEN25 family types under ASME B18.6.3
3.13.1 Nuts shall be designated by the following until ASME B18.24 is revised to list the types covered
data in the sequence shown: product name; dimensional in this Standard.
standard, nominal size (fraction or decimal); threads per
inch; mechanical and performance standard, and grade 3.14 Grade and Manufacturer’s Identification
protective finish (including specification and thickness), Marking
if required. Grade and manufacturer’s markings shall be applied
EXAMPLES: as required by the applicable mechanical and perform-
(1) Square Nut, ASME B18.2.2, 1⁄2-13, ASTM A 563 Grade A, Zinc ance standard except that markings are not required for
Plated per ASTM F 1941 Fe/Zn 3A
the machine screw nuts per Tables 1-1 and 1-2.
(2) Hex Nut, ASME B18.2.2, 3⁄4-16, SAE J995 Grade 5, Steel
(3) Hex Thick Slotted Nut, ASME B18.2.2, 1.000-8, ASTM F 594
(Alloy Group 1) Corrosion Resistant Steel 3.15 Inspection and Quality Assurance
3.13.2 For part identification numbers (PIN), refer Unless otherwise specified, product quality shall be
to ASME B18.24. For machine screw nut PINS, use the determined according to ASME B18.18.2.
3
ASME B18.2.2-2010
Table 1-1 Dimensions of Square and Hex Machine Screw Nuts
Chamfered
F H F H H
G1
G 30 deg 30 deg
No chamfer
allowed Bottom
chamfer
optional
Machine Screw Nuts [Note (1)]
Width Across Corners

Basic Major Bearing Surface
Nominal Diameter Width Across Flats, F Square, G Hex, G1 Thickness
Runout to Thread Axis,
Size of Thread Basic Min. Max. Min. Max. Min. Max. Min. Max. FIM
5
0 0.060 ⁄32 0.150 0.156 0.206 0.221 0.171 0.180 0.043 0.050 0.005
5
1 0.073 ⁄32 0.150 0.156 0.206 0.221 0.171 0.180 0.043 0.050 0.005
3
2 0.086 ⁄16 0.180 0.188 0.247 0.265 0.205 0.217 0.057 0.066 0.006
3
3 0.099 ⁄16 0.180 0.188 0.247 0.265 0.205 0.217 0.057 0.066 0.006
1
4 0.112 ⁄4 0.241 0.250 0.331 0.354 0.275 0.289 0.087 0.098 0.009
5
5 0.125 ⁄16 0.302 0.312 0.415 0.442 0.344 0.361 0.102 0.114 0.011
5
6 0.138 ⁄16 0.302 0.312 0.415 0.442 0.344 0.361 0.102 0.114 0.011
11
8 0.164 ⁄32 0.332 0.344 0.456 0.486 0.378 0.397 0.117 0.130 0.012
3
10 0.190 ⁄8 0.362 0.375 0.497 0.53 0.413 0.433 0.117 0.130 0.013
7
12 0.216 ⁄16 0.423 0.438 0.581 0.619 0.482 0.505 0.148 0.161 0.015
1 7
⁄4 0.250 ⁄16 0.423 0.438 0.581 0.619 0.482 0.505 0.178 0.193 0.015
5 9
⁄16 0.312 ⁄16 0.545 0.562 0.748 0.795 0.621 0.65 0.208 0.225 0.020
3 5
⁄8 0.375 ⁄8 0.607 0.625 0.833 0.884 0.692 0.722 0.239 0.257 0.021
GENERAL NOTES:
(a) For additional requirements refer to section 3, General Data.
(b) Material. Unless otherwise specified, machine screw nuts shall be made of carbon steel.
(c) Mechanical Property Requirements. Unless the purchaser specifies otherwise in the inquiry and purchase documents, machine screw
nuts have no mechanical requirements.
NOTE:
(1) As shown in the figure, no countersink is required.
4
ASME B18.2.2-2010
Table 1-2 Dimensions of Small Pattern Hex Machine Screw Nuts

Chamfered
F H H
G1
30 deg 30 deg
Bottom
chamfer
optional
Note (1)
Bearing
Width Across Surface
Corners Runout
Basic Major to
Nominal Diameter of Width Across Flats, F Hex, G1 Thickness
Thread
Size Thread Basic Min. Max. Min. Max. Min. Max. Axis, FIM
1
0 0.060 ⁄8 0.121 0.125 0.134 0.140 0.043 0.050 0.005
1
1 0.073 ⁄8 0.121 0.125 0.134 0.140 0.043 0.050 0.005
5
2 0.086 ⁄32 0.150 0.156 0.171 0.180 0.057 0.066 0.006
5
3 0.099 ⁄32 0.150 0.156 0.171 0.180 0.057 0.066 0.006
3
4 0.112 ⁄16 0.180 0.188 0.205 0.217 0.087 0.098 0.009
1
5 0.125 ⁄4 0.241 0.25 0.275 0.289 0.102 0.114 0.011
5
6 0.138 ⁄16 0.302 0.312 0.344 0.361 0.102 0.114 0.011
11
8 0.164 ⁄32 0.332 0.344 0.378 0.397 0.117 0.13 0.012
3
10 0.19 ⁄8 0.362 0.375 0.413 0.433 0.117 0.13 0.013
GENERAL NOTES:
(b) Material. Unless otherwise specified, machine screw nuts shall be made of carbon steel.
(c) Mechanical Property Requirements. Unless the purchaser specifies otherwise in the inquiry and purchase documents, machine screw
nuts have no mechanical requirements.
NOTE:
5
ASME B18.2.2-2010
Table 2 Dimensions of Square Nuts
G H H
25 deg
approx.
F
25 deg 25 deg
approx. approx.
Optional
Note (1)
Bearing Surface
Basic Major Width Across Flats, F Width Across Runout to
Nominal Diameter of [Note (2)] Corners, G Thickness Thread Axis,
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. FIM
1 7 7
⁄4 0.2500 ⁄16 0.425 0.438 0.554 0.619 ⁄32 0.203 0.235 0.011
5 9 17
⁄16 0.3125 ⁄16 0.547 0.562 0.721 0.795 ⁄64 0.249 0.283 0.015
3 5 21
⁄8 0.3750 ⁄8 0.606 0.625 0.802 0.884 ⁄64 0.310 0.346 0.016
7 3 3
⁄16 0.4375 ⁄4 0.728 0.750 0.970 1.061 ⁄8 0.356 0.394 0.019
1 13 7
⁄2 0.5000 ⁄16 0.788 0.812 1.052 1.149 ⁄16 0.418 0.458 0.022
5 35
⁄8 0.6250 1 0.969 1.000 1.300 1.414 ⁄64 0.525 0.569 0.026
3
⁄4 0.7500 11⁄8 1.088 1.125 1.464 1.591 21
⁄32 0.632 0.680 0.029
7
⁄8 0.8750 15⁄16 1.269 1.312 1.712 1.856 49
⁄64 0.740 0.792 0.034
1 1.0000 11⁄2 1.450 1.500 1.961 2.121 7
⁄8 0.847 0.903 0.039
11⁄8 1.1250 111⁄16 1.631 1.688 2.209 2.386 1 0.970 1.030 0.029
11⁄4 1.2500 17⁄8 1.812 1.875 2.458 2.652 13⁄32 1.062 1.126 0.032
13⁄8 1.3750 21⁄16 1.994 2.062 2.708 2.917 113⁄64 1.169 1.237 0.035
11⁄2 1.5000 21⁄4 2.175 2.250 2.956 3.182 15⁄16 1.276 1.348 0.039
GENERAL NOTE: For additional requirements, refer to section 3, General Data.

NOTES:
(1) See para. 3.1.
6
ASME B18.2.2-2010
Table 3 Dimensions of Hex Flat Nuts and Hex Flat Jam Nuts
F H H1
Note (1)
Width Across
Width Across Flats, F Corners, G Thickness Hex Flat Thickness Hex Flat
Basic Major Bearing Surface
[Note (2)] [Note (3)] Nuts, H Jam Nuts, H1
Nominal Diameter of Runout to Thread
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Basic Min. Max. Axis, FIM
11⁄8 1.1250 111⁄16 1.631 1.688 1.859 1.949 1 0.970 1.030 5

⁄8 0.595 0.655 0.029
11⁄4 1.2500 17⁄8 1.812 1.875 2.066 2.165 13⁄32 1.062 1.126 3
⁄4 0.718 0.782 0.032
13⁄8 1.3750 21⁄16 1.994 2.062 2.273 2.382 113⁄64 1.169 1.237 13
⁄16 0.778 0.846 0.035
11⁄2 1.5000 21⁄4 2.175 2.250 2.480 2.598 15⁄16 1.276 1.348 7
⁄8 0.839 0.911 0.039

NOTES:
(2) See para. 3.1.
(3) See para. 3.2.
7
ASME B18.2.2-2010
Table 4 Dimensions of Hex Nuts and Hex Jam Nuts
F H H H1 H1
0.016 in. 0.016 in.
approx. approx.
Maximum Runout of Bearing

Surface to Thread Axis, FIM
Hex Nuts
Specified Proof Hex Jam
Load Nuts
Basic Major Width Across Width Across Thickness Hex Thickness Jam Up to 150,000 All
Nominal Diameter of Flats, F Corners, G Nuts, H Nuts, H1 150,000 psi and Strength
Size Thread Min. Max. Min. Max. Min. Max. Min. Max. psi Greater Levels
1
⁄4 0.2500 0.428 0.438 0.488 0.505 0.212 0.226 0.150 0.163 0.015 0.010 0.015
5
⁄16 0.3125 0.489 0.500 0.557 0.577 0.258 0.273 0.180 0.195 0.016 0.011 0.016
3
⁄8 0.3750 0.551 0.563 0.628 0.650 0.320 0.337 0.210 0.227 0.017 0.012 0.017
7
⁄16 0.4375 0.675 0.688 0.768 0.794 0.365 0.385 0.240 0.260 0.018 0.013 0.018
1
⁄2 0.5000 0.736 0.750 0.840 0.866 0.427 0.448 0.302 0.323 0.019 0.014 0.019
9
⁄16 0.5625 0.861 0.875 0.982 1.010 0.473 0.496 0.301 0.324 0.020 0.015 0.020
5
⁄8 0.6250 0.922 0.938 1.051 1.083 0.535 0.559 0.363 0.387 0.021 0.016 0.021
3
⁄4 0.7500 1.088 1.125 1.240 1.299 0.617 0.665 0.398 0.446 0.023 0.018 0.023
7
⁄8 0.8750 1.269 1.312 1.447 1.516 0.724 0.776 0.458 0.510 0.025 0.020 0.025
1 1.0000 1.450 1.500 1.653 1.732 0.831 0.887 0.519 0.575 0.027 0.022 0.027
11⁄8 1.1250 1.631 1.688 1.859 1.949 0.939 0.999 0.579 0.639 0.030 0.025 0.030
11⁄4 1.2500 1.812 1.875 2.066 2.165 1.030 1.094 0.687 0.751 0.033 0.028 0.033
13⁄8 1.3750 1.994 2.062 2.273 2.382 1.138 1.206 0.747 0.815 0.036 0.031 0.036
11⁄2 1.5000 2.175 2.250 2.480 2.598 1.245 1.317 0.808 0.880 0.039 0.034 0.039
15⁄8 1.6250 2.35 2.43 2.679 2.805 1.364 1.416 0.868 0.944 0.044 0.038 0.044
13⁄4 1.7500 2.538 2.625 2.893 3.031 1.460 1.540 0.929 1.009 0.048 0.041 0.048
17⁄8 1.8750 2.722 2.813 3.103 3.247 1.567 1.651 0.989 1.073 0.051 0.044 0.051
2 2.0000 2.900 3.000 3.306 3.464 1.675 1.763 1.050 1.138 0.055 0.047 0.055
21⁄4 2.2500 3.263 3.375 3.719 3.897 1.890 1.986 1.155 1.267 0.061 0.052 0.061
21⁄2 2.5000 3.625 3.750 4.133 4.330 2.105 2.209 1.401 1.427 0.068 0.058 0.068
23⁄4 2.7500 3.988 4.125 4.546 4.763 2.319 2.431 1.522 1.556 0.074 0.064 0.074
3 3.0000 4.350 4.500 4.959 5.196 2.534 2.654 1.643 1.685 0.081 0.070 0.081
31⁄4 3.2500 4.713 4.875 5.373 5.629 2.749 2.877 1.748 1.814 0.087 0.075 0.087
31⁄2 3.5000 5.075 5.250 5.786 6.062 2.964 3.100 1.870 1.943 0.094 0.081 0.094
33⁄4 3.7500 5.438 5.625 6.199 6.495 3.178 3.322 1.990 2.072 0.100 0.087 0.100
4 4.0000 5.800 6.000 6.612 6.928 3.393 3.545 2.112 2.201 0.107 0.093 0.107
8
ASME B18.2.2-2010
Table 5 Dimensions of Hex Slotted Nuts

F H H
0.016 in. T
approx.
Maximum
Runout of
Width Across Unslotted Bearing
Basic Major Width Across Flats, F Corners, G Thickness, T Width of Slot, S Surface to
Nominal Diameter of [Note (1)] [Note (2)] Thickness, H [Note (3)] [Note (3)]
Thread Axis,
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Min. Max. Min. Max. FIM [Note (4)]
1 7 7
⁄4 0.2500 ⁄16 0.428 0.438 0.488 0.505 ⁄32 0.212 0.226 0.12 0.14 0.07 0.10 0.015
5 1 17
⁄16 0.3125 ⁄2 0.489 0.500 0.557 0.577 ⁄64 0.258 0.273 0.16 0.18 0.09 0.12 0.016
3 9 21
⁄8 0.3750 ⁄16 0.551 0.562 0.628 0.650 ⁄64 0.320 0.337 0.19 0.21 0.12 0.15 0.018
7 11 3
⁄16 0.4375 ⁄16 0.675 0.688 0.768 0.794 ⁄8 0.365 0.385 0.21 0.23 0.12 0.15 0.018
1 3 7
⁄2 0.5000 ⁄4 0.736 0.750 0.840 0.866 ⁄16 0.427 0.448 0.27 0.29 0.15 0.18 0.019
9 7 31
⁄16 0.5625 ⁄8 0.861 0.875 0.982 1.010 ⁄64 0.473 0.496 0.29 0.31 0.15 0.18 0.020
5 15 35
⁄8 0.6250 ⁄16 0.922 0.938 1.051 1.083 ⁄64 0.535 0.559 0.32 0.34 0.18 0.24 0.021
3
⁄4 0.7500 11⁄8 1.088 1.125 1.240 1.299 41
⁄64 0.617 0.665 0.38 0.40 0.18 0.24 0.023
7
⁄8 0.8750 15⁄16 1.269 1.312 1.447 1.516 3
⁄4 0.724 0.776 0.49 0.52 0.18 0.24 0.025
1 1.0000 11⁄2 1.450 1.500 1.653 1.732 55
⁄64 0.831 0.887 0.56 0.59 0.24 0.30 0.027
11⁄8 1.1250 111⁄16 1.631 1.688 1.859 1.949 31
⁄32 0.939 0.999 0.61 0.64 0.24 0.33 0.030
11⁄4 1.2500 17⁄8 1.812 1.875 2.066 2.165 11⁄16 1.030 1.094 0.67 0.70 0.31 0.40 0.033
13⁄8 1.3750 21⁄16 1.994 2.062 2.273 2.382 111⁄64 1.138 1.206 0.78 0.82 0.31 0.40 0.036
11⁄2 1.5000 21⁄4 2.175 2.250 2.480 2.598 19⁄32 1.245 1.317 0.82 0.86 0.37 0.46 0.039

NOTES:
(1) See para. 3.1.
(2) See para. 3.2.
(3) See para. 3.7.
(4) See paras. 3.3 and 3.9.
9
ASME B18.2.2-2010
Table 6 Dimensions of Hex Thick Nuts
F H H
0.016 in.
approx.

Width Across [Note (3)]
Basic Major Width Across Flats, F Corners, G Specified Proof Load

Nominal Diameter of [Note (1)] [Note (2)] Thickness, H Up to 150,000 psi
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. 150,000 psi and Greater
1 7 9
⁄4 0.2500 ⁄16 0.428 0.438 0.488 0.505 ⁄32 0.274 0.288 0.015 0.010
5 1 21
⁄16 0.3125 ⁄2 0.489 0.500 0.557 0.577 ⁄64 0.320 0.336 0.016 0.011
3 9 13
⁄8 0.3750 ⁄16 0.551 0.562 0.628 0.650 ⁄32 0.398 0.415 0.017 0.012
7 11 29
⁄16 0.4375 ⁄16 0.675 0.688 0.768 0.794 ⁄64 0.444 0.463 0.018 0.013
1 3 9
⁄2 0.5000 ⁄4 0.736 0.750 0.840 0.866 ⁄16 0.552 0.573 0.019 0.014
9 7 39
⁄16 0.5625 ⁄8 0.861 0.875 0.892 1.010 ⁄64 0.598 0.621 0.020 0.015
5 15 23
⁄8 0.6250 ⁄16 0.922 0.938 1.051 1.083 ⁄32 0.706 0.731 0.021 0.016
3
⁄4 0.7500 11⁄8 1.088 1.125 1.240 1.299 13
⁄16 0.798 0.827 0.023 0.018
7
⁄8 0.8750 15⁄16 1.269 1.312 1.447 1.516 29
⁄32 0.890 0.922 0.025 0.020
1 1.0000 11⁄2 1.450 1.500 1.653 1.732 1 0.982 1.018 0.027 0.022
11⁄8 1.1250 111⁄16 1.631 1.688 1.859 1.949 15⁄32 1.136 1.176 0.030 0.025
11⁄4 1.2500 17⁄8 1.812 1.875 2.066 2.165 11⁄4 1.228 1.272 0.033 0.028
13⁄8 1.3750 21⁄16 1.994 2.062 2.273 2.382 13⁄8 1.351 1.399 0.036 0.031
11⁄2 1.5000 21⁄4 2.175 2.250 2.480 2.598 11⁄2 1.474 1.526 0.039 0.034

NOTES:
(1) See para. 3.1.
(2) See para. 3.2.
10
ASME B18.2.2-2010
Table 7 Dimensions of Hex Thick Slotted Nuts
F H H
0.016 in. T
approx.
Maximum
Runout of
Width Across Unslotted Bearing
Basic Major Width Across Flats, F Corners, G Thickness, T Width of Slot, S Surface to
Nominal Diameter of [Note (1)] [Note (2)] Thickness, H [Note (3)] [Note (3)] Thread Axis,
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Min. Max. Min. Max. FIM [Note (4)]
1 7 9
⁄4 0.2500 ⁄16 0.428 0.438 0.488 0.505 ⁄32 0.274 0.288 0.18 0.20 0.07 0.10 0.015
5 1 21
⁄16 0.3125 ⁄2 0.489 0.500 0.557 0.577 ⁄64 0.320 0.336 0.22 0.24 0.09 0.12 0.016
3 9 13
⁄8 0.3750 ⁄16 0.551 0.562 0.628 0.650 ⁄32 0.398 0.415 0.27 0.29 0.12 0.15 0.017
7 11 29
⁄16 0.4375 ⁄16 0.675 0.688 0.768 0.794 ⁄64 0.444 0.463 0.29 0.31 0.12 0.15 0.018
1 3 9
⁄2 0.5000 ⁄4 0.736 0.750 0.840 0.866 ⁄16 0.552 0.573 0.40 0.42 0.15 0.18 0.019
9 7 39
⁄16 0.5625 ⁄8 0.861 0.875 0.982 1.010 ⁄64 0.598 0.621 0.41 0.43 0.15 0.18 0.020
5 15 23
⁄8 0.6250 ⁄16 0.922 0.938 1.051 1.083 ⁄32 0.706 0.731 0.49 0.51 0.18 0.24 0.021
3
⁄4 0.7500 11⁄8 1.088 1.125 1.240 1.299 13
⁄16 0.798 0.827 0.55 0.57 0.18 0.24 0.023
7
⁄8 0.8750 15⁄16 1.269 1.312 1.447 1.516 29
⁄32 0.890 0.922 0.64 0.67 0.18 0.24 0.025
1 1.0000 11⁄2 1.450 1.500 1.653 1.732 1 0.982 1.018 0.70 0.73 0.24 0.30 0.027
11⁄8 1.1250 111⁄16 1.631 1.688 1.859 1.949 15⁄32 1.136 1.176 0.80 0.83 0.24 0.33 0.030
11⁄4 1.2500 17⁄8 1.812 1.875 2.066 2.165 11⁄4 1.228 1.272 0.86 0.89 0.31 0.40 0.033
13⁄8 1.3750 21⁄16 1.994 2.062 2.273 2.382 13⁄8 1.351 1.399 0.98 1.02 0.31 0.40 0.036
11⁄2 1.5000 21⁄4 2.175 2.250 2.480 2.598 11⁄2 1.474 1.526 1.04 1.08 0.37 0.46 0.039

NOTES:
(1) See para. 3.1.
(2) See para. 3.2.
(3) See para. 3.7.
11
ASME B18.2.2-2010
Table 8 Dimensions of Heavy Square Nuts
G H H
F
25 deg 25 deg 25 deg
approx. approx. approx.
Optional
Note (1)
Bearing
Surface
Basic Major Width Across Flats, F Width Across Runout to
Nominal Diameter of [Note (2)] Corners, G Thickness, H
Thread
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Axis, FIM
1 1 1
⁄4 0.2500 ⁄2 0.488 0.500 0.640 0.707 ⁄4 0.218 0.266 0.026
5 9 5
⁄16 0.3125 ⁄16 0.546 0.562 0.720 0.795 ⁄16 0.280 0.330 0.030
3 11 3
⁄8 0.3750 ⁄16 0.669 0.688 0.889 0.973 ⁄8 0.341 0.393 0.036
7 3 7
⁄16 0.4375 ⁄4 0.728 0.750 0.970 1.060 ⁄16 0.403 0.456 0.039
1 7 1
⁄2 0.5000 ⁄8 0.850 0.875 1.137 1.237 ⁄2 0.464 0.520 0.046
5
⁄8 0.6250 11⁄16 1.031 1.062 1.386 1.503 5
⁄8 0.587 0.647 0.056
3
⁄4 0.7500 11⁄4 1.212 1.250 1.635 1.768 3
⁄4 0.710 0.774 0.065
7
⁄8 0.8750 17⁄16 1.394 1.438 1.884 2.033 7
⁄8 0.833 0.901 0.075
1 1.0000 15⁄8 1.575 1.625 2.132 2.298 1 0.956 1.028 0.082
11⁄8 1.1250 113⁄16 1.756 1.812 2.381 2.563 11⁄8 1.079 1.155 0.063
11⁄4 1.2500 2 1.938 2.000 2.631 2.828 11⁄4 1.187 1.282 0.070
13⁄8 1.3750 23⁄16 2.119 2.188 2.879 3.094 13⁄8 1.310 1.409 0.076
11⁄2 1.5000 23⁄8 2.300 2.375 3.128 3.359 11⁄2 1.433 1.536 0.082

NOTES:
(2) See para. 3.1.
12
ASME B18.2.2-2010
Table 9 Dimensions of Heavy Hex Flat Nuts and Heavy Hex Flat Jam Nuts
F H H1
Note (1)
Bearing
Width Across Surface
Basic Major Width Across Flats, F Corners, G Thickness Heavy Hex Thickness Heavy Hex Runout to
[Note (2)] [Note (3)] Flat Nuts, H Flat Jam Nuts, H1
Nominal Diameter of Thread Axis,
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Basic Min. Max. FIM
11⁄8 1.1250 113⁄16 1.756 1.812 2.002 2.093 11⁄8 1.079 1.155 5
⁄8 0.579 0.655 0.032
11⁄4 1.2500 2 1.938 2.000 2.209 2.309 11⁄4 1.187 1.282 3
⁄4 0.687 0.782 0.034
13⁄8 1.3750 23⁄16 2.119 2.188 2.416 2.526 13⁄8 1.310 1.409 13
⁄16 0.747 0.846 0.038
11⁄2 1.5000 23⁄8 2.300 2.375 2.622 2.742 11⁄2 1.433 1.536 7
⁄8 0.808 0.911 0.041
13⁄4 1.7500 23⁄4 2.662 2.750 3.035 3.175 13⁄4 1.679 1.790 1 0.929 1.040 0.048
2 2.0000 31⁄8 3.025 3.125 3.449 3.608 2 1.925 2.044 11⁄8 1.050 1.169 0.054
21⁄4 2.2500 31⁄2 3.388 3.500 3.862 4.041 21⁄4 2.155 2.298 11⁄4 1.155 1.298 0.061
21⁄2 2.5000 37⁄8 3.750 3.875 4.275 4.474 21⁄2 2.401 2.552 11⁄2 1.401 1.552 0.067
23⁄4 2.7500 41⁄4 4.112 4.250 4.688 4.907 23⁄4 2.647 2.806 15⁄8 1.522 1.681 0.074
3 3.0000 45⁄8 4.475 4.625 5.102 5.340 3 2.893 3.060 13⁄4 1.643 1.810 0.080
31⁄4 3.2500 5 4.838 5.000 5.515 5.774 31⁄4 3.124 3.314 17⁄8 1.748 1.939 0.087
31⁄2 3.5000 53⁄8 5.200 5.375 5.928 6.207 31⁄2 3.370 3.568 2 1.870 2.068 0.093
33⁄4 3.7500 53⁄4 5.562 5.750 6.341 6.640 33⁄4 3.616 3.822 21⁄8 1.990 2.197 0.100
4 4.0000 61⁄8 5.925 6.125 6.755 7.073 4 3.862 4.076 21⁄4 2.112 2.326 1.06

NOTES:
(2) See para. 3.1.
(3) See para. 3.2.
13
ASME B18.2.2-2010
Table 10 Dimensions of Heavy Hex Nuts and Heavy Hex Jam Nuts
F H H H1 H1
0.016 in. 0.016 in.
approx. approx.

[Note (3)]
Heavy Hex Nuts Heavy
Specified Proof Hex Jam
Width Across Load Nuts
Basic Major Width Across Flats, F Corners, G Thickness Heavy Hex Thickness Heavy Up to 150,000 All
Nominal Diameter [Note (1)] [Note (2)] Nuts, H Hex Jam Nuts, H1 150,000 psi and Strength
Size of Thread Basic Min. Max. Min. Max. Basic Min. Max. Basic Min. Max. psi Greater Levels
1 1 15 11
⁄4 0.2500 ⁄2 0.488 0.500 0.556 0.577 ⁄64 0.218 0.250 ⁄64 0.156 0.188 0.017 0.011 0.017
5 9 19 13
⁄16 0.3125 ⁄16 0.546 0.562 0.622 0.650 ⁄64 0.280 0.314 ⁄64 0.186 0.220 0.020 0.012 0.020
3 11 23 15
⁄8 0.3750 ⁄16 0.669 0.688 0.763 0.794 ⁄64 0.341 0.377 ⁄64 0.216 0.252 0.021 0.014 0.021
7 3 27 17
⁄16 0.4375 ⁄4 0.728 0.750 0.830 0.866 ⁄64 0.403 0.441 ⁄64 0.247 0.285 0.022 0.015 0.022
1 7 31 19
⁄2 0.5000 ⁄8 0.850 0.875 0.969 1.010 ⁄64 0.464 0.504 ⁄64 0.277 0.317 0.023 0.016 0.023
9 15 35 21
⁄16 0.5625 ⁄16 0.909 0.938 1.037 1.083 ⁄64 0.526 0.568 ⁄64 0.307 0.349 0.024 0.017 0.024
5
⁄8 0.6250 11⁄16 1.031 1.062 1.175 1.227 39
⁄64 0.587 0.631 23
⁄64 0.337 0.381 0.025 0.018 0.025
3
⁄4 0.7500 11⁄4 1.212 1.250 1.382 1.443 47
⁄64 0.710 0.758 27
⁄64 0.398 0.446 0.027 0.020 0.027
7
⁄8 0.8750 17⁄16 1.394 1.438 1.589 1.660 55
⁄64 0.833 0.885 31
⁄64 0.458 0.510 0.029 0.022 0.029
1 1.0000 15⁄8 1.575 1.625 1.796 1.876 63
⁄64 0.956 1.012 35
⁄64 0.519 0.575 0.031 0.024 0.031
11⁄8 1.1250 113⁄16 1.756 1.812 2.002 2.093 17⁄64 1.079 1.139 39
⁄64 0.579 0.639 0.033 0.027 0.033
11⁄4 1.2500 2 1.938 2.000 2.209 2.309 17⁄32 1.187 1.251 23
⁄32 0.687 0.751 0.035 0.030 0.035
13⁄8 1.3750 23⁄16 2.119 2.188 2.416 2.526 111⁄32 1.310 1.378 25
⁄32 0.747 0.815 0.038 0.033 0.038
11⁄2 1.5000 23⁄8 2.300 2.375 2.622 2.742 115⁄32 1.433 1.505 27
⁄32 0.808 0.880 0.041 0.036 0.041
15⁄8 1.6250 29⁄16 2.481 2.562 2.828 2.959 119⁄32 1.556 1.632 29
⁄32 0.868 0.944 0.044 0.038 0.044
13⁄4 1.7500 23⁄4 2.662 2.750 3.035 3.175 123⁄32 1.679 1.759 31
⁄32 0.929 1.009 0.048 0.041 0.048
17⁄8 1.8750 215⁄16 2.844 2.938 3.242 3.392 127⁄32 1.802 1.886 11⁄32 0.989 1.073 0.051 0.044 0.051
2 2.0000 31⁄8 3.025 3.125 3.449 3.608 131⁄32 1.925 2.013 13⁄32 1.050 1.138 0.055 0.047 0.055
21⁄4 2.2500 31⁄2 3.388 3.500 3.862 4.041 213⁄64 2.155 2.251 113⁄64 1.155 1.251 0.061 0.052 0.061
21⁄2 2.5000 37⁄8 3.750 3.875 4.275 4.474 229⁄64 2.401 2.505 129⁄64 1.401 1.505 0.068 0.058 0.068
23⁄4 2.7500 41⁄4 4.112 4.250 4.688 4.907 245⁄64 2.647 2.759 137⁄64 1.522 1.634 0.074 0.064 0.074
3 3.0000 45⁄8 4.475 4.625 5.102 5.340 261⁄64 2.893 3.013 145⁄64 1.643 1.763 0.081 0.070 0.081
31⁄4 3.2500 5 4.838 5.000 5.515 5.774 33⁄16 3.124 3.252 113⁄16 1.748 1.876 0.087 0.075 0.087
31⁄2 3.5000 53⁄8 5.200 5.375 5.928 6.207 37⁄16 3.370 3.506 115⁄16 1.870 2.006 0.094 0.081 0.094
33⁄4 3.7500 53⁄4 5.562 5.750 6.341 6.640 311⁄16 3.616 3.760 21⁄16 1.990 2.134 0.100 0.087 0.100
4 4.0000 61⁄8 5.925 6.125 6.755 7.073 315⁄16 3.862 4.014 23⁄16 2.112 2.264 0.107 0.093 0.107
GENERAL NOTES:
(b) Chamfers and Washer Faces. Nuts in sizes 7⁄16 in. nominal size and smaller shall be double-chamfered. Larger size nuts shall be dou-
ble-chamfered or have washer-faced bearing surface and chamfered top.
(c) Optional Bearing Surface Runout. Where purchaser specifies close runout of bearing face style heavy hex or heavy hex jam nuts in nom-
inal sizes 2 in. to 4 in., nuts shall be so processed as to have a maximum bearing face runout of 0.010 in. FIM.
NOTES:
(1) See para. 3.1.
(2) See para. 3.2.
14
ASME B18.2.2-2010
Table 11 Dimensions of Heavy Hex Slotted Nuts
F H H
0.016 in. T
approx.
Maximum
Runout of
Bearing
Width Across Unslotted Width of Surface
Basic Major Width Across Flats, F Corners, G Thickness, T Slot, S to Thread
Nominal Diameter of [Note (1)] [Note (2)] Thickness, H [Note (3)] [Note (3)] Axis, FIM
Size Thread Basic Min. Max. Min. Max. Basic Min. Max. Min. Max. Min. Max. [Note (4)]
1 1 15
⁄4 0.2500 ⁄2 0.488 0.500 0.556 0.577 ⁄64 0.218 0.250 0.13 0.15 0.07 0.10 0.017
5 9 19
⁄16 0.3125 ⁄16 0.546 0.562 0.622 0.650 ⁄64 0.280 0.314 0.19 0.21 0.09 0.12 0.020
3 11 23
⁄8 0.3750 ⁄16 0.669 0.688 0.763 0.794 ⁄64 0.341 0.377 0.22 0.24 0.12 0.15 0.021
7 3 27
⁄16 0.4375 ⁄4 0.728 0.750 0.830 0.866 ⁄64 0.403 0.441 0.26 0.28 0.12 0.15 0.022
1 7 31
⁄2 0.5000 ⁄8 0.850 0.875 0.969 1.010 ⁄64 0.464 0.504 0.32 0.34 0.15 0.18 0.023
9 15 35
⁄16 0.5625 ⁄16 0.909 0.938 1.037 1.083 ⁄64 0.526 0.568 0.35 0.37 0.15 0.18 0.024
5
⁄8 0.6250 11⁄16 1.031 1.062 1.175 1.227 39
⁄64 0.587 0.631 0.38 0.40 0.18 0.24 0.025
3
⁄4 0.7500 11⁄4 1.212 1.250 1.382 1.443 47
⁄64 0.710 0.758 0.47 0.49 0.18 0.24 0.027
7
⁄8 0.8750 17⁄16 1.394 1.438 1.589 1.660 55
⁄64 0.833 0.885 0.59 0.62 0.18 0.24 0.029
1 1.0000 15⁄8 1.575 1.625 1.796 1.876 63
⁄64 0.956 1.012 0.69 0.72 0.24 0.30 0.031
11⁄8 1.1250 113⁄16 1.756 1.812 2.002 2.093 17⁄64 1.079 1.139 0.75 0.78 0.24 0.33 0.033
11⁄4 1.2500 2 1.938 2.000 2.209 2.309 17⁄32 1.187 1.251 0.83 0.86 0.31 0.40 0.035
13⁄8 1.3750 23⁄16 2.119 2.188 2.416 2.526 111⁄32 1.310 1.378 0.95 0.99 0.31 0.40 0.038
11⁄2 1.5000 23⁄8 2.300 2.375 2.622 2.742 115⁄32 1.433 1.505 1.01 1.05 0.37 0.46 0.041
13⁄4 1.7500 23⁄4 2.662 2.750 3.035 3.175 123⁄32 1.679 1.759 1.20 1.24 0.43 0.52 0.048
2 2.0000 31⁄8 3.025 3.125 3.449 3.608 131⁄32 1.925 2.013 1.38 1.43 0.43 0.52 0.055
21⁄4 2.2500 31⁄2 3.388 3.500 3.862 4.041 213⁄64 2.155 2.251 1.62 1.67 0.43 0.52 0.061
21⁄2 2.5000 37⁄8 3.750 3.875 4.275 4.474 229⁄64 2.401 2.505 1.74 1.79 0.55 0.64 0.068
23⁄4 2.7500 41⁄4 4.112 4.250 4.688 4.907 245⁄64 2.647 2.759 1.99 2.05 0.55 0.64 0.074
3 3.0000 45⁄8 4.475 4.625 5.102 5.340 261⁄64 2.893 3.013 2.17 2.23 0.62 0.71 0.081
31⁄4 3.2500 5 4.838 5.000 5.515 5.774 33⁄16 3.124 3.252 2.41 2.47 0.62 0.71 0.087
31⁄2 3.5000 53⁄8 5.200 5.375 5.928 6.207 37⁄16 3.370 3.506 2.65 2.72 0.62 0.71 0.094
33⁄4 3.7500 53⁄4 5.562 5.750 6.341 6.640 311⁄16 3.616 3.760 2.90 2.97 0.62 0.71 0.100
4 4.0000 61⁄8 5.925 6.125 6.755 7.073 315⁄16 3.862 4.014 3.15 3.22 0.62 0.71 0.107
GENERAL NOTES:
(a) For additional requirements, refer to section 3, General Data.
(b) Chamfers and Washer Faces. Nuts in sizes 7⁄16 in. nominal size and smaller shall be double-chamfered. Larger size nuts shall be
double-chamfered or have washer-faced bearing surface and chamfered top.
NOTES:
(1) See para. 3.1.
(2) See para. 3.2.
(3) See para. 3.7.
15
ASME B18.2.2-2010
Table 12 Dimensions of Hex Flange Nuts and Large Hex Flange Nuts
H
B
J
F
K
Slight rounding
permissible
30 deg REF
Maximum
Runout of
Minimum Bearing
Basic Major Width Across Width Across Diameter Nut Thickness, Minimum Flange Surface
Nominal Diameter of Flats, F Corners, G Flange, B H Wrenching Thickness, to Thread
Size Thread Min. Max. Min. Max. Min. Max. Min. Max. Length, J K Axis, FIM
Hex Flange Nuts

No. 6 0.1380 0.302 0.312 0.342 0.361 0.406 0.422 0.156 0.171 0.10 0.02 0.014
8 0.1640 0.334 0.344 0.381 0.397 0.452 0.469 0.187 0.203 0.13 0.02 0.016
10 0.1900 0.365 0.375 0.416 0.433 0.480 0.500 0.203 0.219 0.13 0.03 0.017
12 0.2160 0.428 0.438 0.488 0.505 0.574 0.594 0.222 0.236 0.14 0.04 0.020
1
⁄4 0.2500 0.428 0.438 0.488 0.505 0.574 0.594 0.222 0.236 0.14 0.04 0.020
5
⁄16 0.3125 0.489 0.500 0.557 0.577 0.660 0.680 0.268 0.283 0.17 0.04 0.023
3
⁄8 0.3750 0.551 0.562 0.628 0.650 0.728 0.750 0.330 0.347 0.23 0.04 0.025
7
⁄16 0.4375 0.675 0.688 0.768 0.794 0.910 0.937 0.375 0.395 0.26 0.04 0.032
1
⁄2 0.5000 0.736 0.750 0.840 0.866 1.000 1.031 0.437 0.458 0.31 0.05 0.035
9
⁄16 0.5625 0.861 0.875 0.982 1.010 1.155 1.188 0.483 0.506 0.35 0.05 0.040
5
⁄8 0.6250 0.922 0.938 1.051 1.083 1.248 1.281 0.545 0.569 0.40 0.05 0.044
3
⁄4 0.7500 1.088 1.125 1.240 1.299 1.460 1.500 0.627 0.675 0.46 0.06 0.051
Large Hex Flange Nuts
1
⁄4 0.2500 0.428 0.438 0.488 0.505 0.700 0.728 0.281 0.312 0.15 0.04 0.024
5
⁄16 0.3125 0.489 0.500 0.557 0.577 0.790 0.820 0.343 0.375 0.20 0.04 0.028
3
⁄8 0.3750 0.551 0.562 0.628 0.650 0.885 0.915 0.390 0.406 0.24 0.04 0.031
7
⁄16 0.4375 0.675 0.688 0.768 0.794 1.100 1.131 0.437 0.468 0.26 0.04 0.038
1
⁄2 0.5000 0.736 0.750 0.840 0.866 1.175 1.205 0.485 0.515 0.29 0.06 0.041
9
⁄16 0.5625 0.861 0.875 0.982 1.010 1.260 1.300 0.546 0.578 0.37 0.06 0.044
5
⁄8 0.6250 0.922 0.938 1.051 1.083 1.280 1.360 0.600 0.640 0.42 0.06 0.045
GENERAL NOTES:
(b) Concentricity of Tapped Hole. Axis of tapped hole shall be concentric with axis of nut body within a tolerance equal to 3% (6% FIM) of
the maximum width across flats.
16
ASME B18.2.2-2010
Table 13 Dimensions of Hex Coupling Nuts

F H
Note (1)
0.5H
Basic Major Width Across

Nominal Diameter of Width Across Flats, F Corners, G Length, H
Size Thread Basic Min. Max. Min. Max. Basic Min. Max.
5 1
#6 0.138 ⁄16 0.302 0.312 0.344 0.361 ⁄2 0.470 0.510
5 5
#8 0.164 ⁄16 0.302 0.312 0.344 0.361 ⁄8 0.595 0.645
5 3
#10 0.190 ⁄16 0.302 0.312 0.344 0.361 ⁄4 0.711 0.760
1 7
⁄4 0.250 ⁄16 0.428 0.438 0.488 0.505 13⁄4 1.690 1.760
5 1
⁄16 0.312 ⁄2 0.489 0.500 0.557 0.577 13⁄4 1.690 1.760
3 9
⁄8 0.375 ⁄16 0.551 0.562 0.628 0.650 13⁄4 1.690 1.760
7 5
⁄16 0.437 ⁄8 0.607 0.625 0.692 0.722 13⁄4 1.690 1.760
1 11
⁄2 0.500 ⁄16 0.663 0.688 0.756 0.794 13⁄4 1.690 1.760
9 13
⁄16 0.562 ⁄16 0.782 0.813 0.891 0.939 21⁄8 2.067 2.135
5 13
⁄8 0.625 ⁄16 0.782 0.813 0.891 0.939 21⁄8 2.067 2.135
3
⁄4 0.750 1 0.963 1.000 1.097 1.155 21⁄4 2.190 2.260
7
⁄8 0.875 11⁄4 1.212 1.250 1.382 1.443 21⁄2 2.440 2.510
1 1.000 13⁄8 1.325 1.375 1.511 1.588 23⁄4 2.690 2.760
11⁄8 1.125 11⁄2 1.450 1.500 1.653 1.732 3 2.940 3.010
11⁄4 0.125 15⁄8 1.575 1.625 1.825 1.876 3 2.940 3.010
11⁄2 1.500 2 1.950 2.000 2.275 2.309 31⁄2 3.440 3.510
15⁄8 1.625 29⁄16 2.481 2.562 2.828 2.959 47⁄8 4.830 4.910
13⁄4 1.750 23⁄4 2.662 2.750 3.035 3.175 51⁄4 5.210 5.290
17⁄8 1.875 215⁄16 2.844 2.938 3.242 3.392 55⁄8 5.580 5.670
2 2.000 31⁄8 3.025 3.125 3.448 3.608 6 5.950 6.040
21⁄4 2.250 31⁄2 3.388 3.500 3.862 4.041 63⁄4 6.700 6.800
21⁄2 2.500 37⁄8 3.750 3.875 4.275 4.474 71⁄2 7.440 7.550
23⁄4 2.750 41⁄4 4.112 4.250 4.688 4.907 81⁄4 8.190 8.310
3 3.000 45⁄8 4.475 4.625 5.101 5.340 9 8.940 9.060
31⁄4 3.250 5 4.838 5.000 5.515 5.773 93⁄4 9.680 9.810
31⁄2 3.500 53⁄8 5.200 5.375 5.928 6.206 101⁄2 10.430 10.570
33⁄4 3.750 53⁄4 5.562 5.750 6.340 6.639 111⁄4 11.170 11.320
4 4.000 61⁄8 5.925 6.125 6.754 7.072 12 11.920 12.080
41⁄4 4.250 61⁄2 6.288 6.500 7.168 7.506 123⁄4 12.670 12.830
41⁄2 4.500 67⁄8 6.650 6.875 7.581 7.939 131⁄2 13.420 13.580
43⁄4 4.750 71⁄4 7.012 7.250 7.994 8.372 141⁄4 14.160 14.340
5 5.000 75⁄8 7.375 7.625 8.408 8.805 15 14.910 15.090
51⁄4 5.250 8 7.738 8.000 8.821 9.238 153⁄4 15.650 15.850
51⁄2 5.500 83⁄8 8.100 8.375 9.234 9.671 161⁄2 16.400 16.600
53⁄4 5.750 83⁄4 8.462 8.750 9.647 10.104 171⁄4 17.150 17.350
6 6.000 91⁄8 8.825 9.125 10.060 10.537 18 17.890 18.110
17
ASME B18.2.2-2010
Table 13 Dimensions of Hex Coupling Nuts (Cont‘d)

GENERAL NOTES:
(a) For additional requirements, refer to section 3, General Data.
(b) Concentricity of Tapped Hole. Axis of tapped hole shall be concentric with axis of nut body within a
tolerance equal to 3% (6% FIM) of the maximum width across flats.
(c) Countersink. Tapped hole may be countersunk on both faces.
(d) When specified by the purchaser, different thread sizes or series shall be tapped into the nut from
opposite ends with each thread extending to approximately 0.5H. All other nut dimensions shall
comply with Table 13 unless otherwise agreed to by the supplier and purchaser.
(e) The dimensions in Table 13 are considered standard, but purchasers may specify across flats sizes
and/or lengths that differ from this table.
(f) Hex coupling nuts must conform to the proof load requirements of ASTM A 563, Grade A for heavy
hex nuts.
NOTE:
(1) Nuts shall be furnished without a hole, unless specially ordered by the purchaser. In some
applications it may be desirable to assure that the threaded parts joined by a coupling nut are
each engaged to approximately one-half nut thickness. As a visual inspection aid, a hole drilled
through one side of the nut is recommended. The hole should be located at mid-nut thickness,
and have a diameter of 0.2 to 0.4 times nominal nut size for sizes 21⁄2 in. and smaller, and 1 in.
for sizes 23⁄4 in. and larger.
18
ASME B18.2.2-2010
MANDATORY APPENDIX I
SLOT GAGES AND GAGING FOR SLOTTED NUTS
The gages specified in Table I-1 shall be used to deter- adjacent faces of the nut, consecutively. Slot alignment
mine the acceptability of the alignment and bottom con- shall be considered satisfactory if the gage pin fits into
tours of the slots in slotted nuts in accordance with the the slots without interference at all three gaging posi-
following procedure. tions. The bottom contour shall be acceptable if the gage
The gaging for slot alignment provides for equal varia- pin contacts the bottom surfaces of opposite slots during
tions in the location of the cotter pinhole in the bolt and the alignment gaging at all three positions.
the location of the slots in the nut. Some deviations from the specified gage plug diame-
To inspect the nut, the slotted end of the gage shall ters, D, may be necessary to compensate for variations
be inserted through the threaded hole from the bearing in the nut thread minor diameter due to differences in
surface of the nut. The gage pin shall then be inserted manufacturing practices. To ensure adequate service life,
--`,`,````,`,``,```,``,,``,,,,`,-`-`,,`,,`,`,,`---
into both the gage slot and the nut slots through three gages and gage pins shall be suitably hardened.
19
ASME B18.2.2-2010
Table I-1 Dimensions of Slot Gages and Gage Pins

Pin must be round
Contour beyond this
and straight for
face optional A C
this length H
B
F
G
ED
Contour of head
Hole for attaching optional
0.03R
pin to gage
Gage Gage Pin
Gage Plug
Diameter, D
[Note (1)] Gage Gage Gage Pin
Minimum Maximum Minimum
Coarse Fine Pilot Slot Diameter,
Gage Gage Gage Minimum
Basic Major Pilot Plug Face Thread Thread Diameter, Width, F G Gage Pin
Nominal Diameter of Length, Length, Diameter, +0.000 +0.000 E +0.002 +0.000 Length,
Size Thread A B C −0.001 −0.001 ±0.005 −0.000 −0.002 H
1
⁄4 0.2500 0.288 0.110 0.375 0.196 0.211 0.181 0.065 0.065 1.00
5
⁄16 0.3125 0.316 0.150 0.406 0.252 0.267 0.237 0.085 0.085 1.06
3
⁄8 0.3750 0.415 0.180 0.500 0.307 0.330 0.292 0.115 0.115 1.19
7
⁄16 0.4375 0.463 0.200 0.562 0.360 0.383 0.345 0.115 0.115 1.25
1
⁄2 0.5000 0.573 0.260 0.625 0.417 0.446 0.402 0.145 0.145 1.38
9
⁄16 0.5625 0.621 0.280 0.703 0.472 0.502 0.457 0.145 0.145 1.44
5
⁄8 0.6250 0.731 0.310 0.781 0.527 0.565 0.512 0.175 0.175 1.56
3
⁄4 0.7500 0.827 0.370 0.938 0.642 0.682 0.627 0.175 0.175 1.75
7
⁄8 0.8750 0.922 0.480 1.109 0.755 0.798 0.740 0.175 0.175 1.94
1 1.0000 1.018 0.550 1.250 0.865 0.910 0.850 0.235 0.235 2.12
11⁄8 1.1250 1.176 0.600 1.406 0.970 1.035 0.955 0.235 0.235 2.31
11⁄4 1.2500 1.272 0.660 1.562 1.095 1.160 1.080 0.305 0.305 2.50
13⁄8 1.3750 1.399 0.770 1.718 1.195 1.285 1.180 0.305 0.305 2.69
11⁄2 1.5000 1.526 0.810 1.875 1.320 1.410 1.305 0.365 0.365 2.88
13⁄4 1.7500 1.759 1.190 2.188 1.534 ... 1.519 0.425 0.425 3.25
2 2.0000 2.013 1.370 2.500 1.759 ... 1.744 0.425 0.425 3.62
21⁄4 2.2500 2.251 1.610 2.818 2.009 ... 1.994 0.425 0.425 4.00
21⁄2 2.5000 2.505 1.730 3.125 2.229 ... 2.214 0.545 0.545 4.38
23⁄4 2.7500 2.759 1.980 3.438 2.479 ... 2.464 0.545 0.545 4.75
3 3.0000 3.013 2.160 3.750 2.729 ... 2.714 0.615 0.615 5.12
31⁄4 3.2500 3.252 2.400 4.062 2.979 ... 2.964 0.615 0.615 5.50
31⁄2 3.5000 3.506 2.640 4.375 3.229 ... 3.214 0.615 0.615 5.88
33⁄4 3.7500 3.760 2.890 4.688 3.479 ... 3.464 0.615 0.615 6.25
4 4.0000 4.014 3.140 5.000 3.729 ... 3.714 0.615 0.615 6.62
NOTE:
(1) Diameters tabulated are equivalent to the minimum minor diameters of Class 2B threads. If the nuts are not threaded with unified
coarse (UNC) or fine (UNF) threads, the diameter of gage shall be the same as the diameter of the GO thread plug gage for the bore.
20
ASME B18.2.2-2010
NONMANDATORY APPENDIX A
FORMULAS FOR NUT DIMENSIONS
Ta b l e A - 1 s p e c i f i e s f o r m u l a s f o r va ri ou s n ut
dimensions.
21
ASME B18.2.2-2010
Table A-1 Formulas for Nut Dimensions

Width Across Flats Nut Thickness Width Across Corners
Basic Tolerance Basic Tolerance Limits, G

Nut Type Nut Size [Note (1)] (Minus) [Note (2)] (Plus or Minus) Min. Max.
Square 1
⁄4 to 5⁄8 F p 1.500D + 0.050D H p 0.875D 0.016D + 1.373 ⴛ (Min. F ) 1.4142 ⴛ (Max.F )
0.062 0.012 −0.030
3
⁄4 to 11⁄2 F p 1.500D 0.050 D H p 0.875D 0.016D + 1.373 ⴛ (Min. F ) 1.4142 ⴛ (Max.F )
0.012 –0.030
Hex Flat 11⁄8 to 11⁄2 F p 1.500D 0.050D H p 0.875D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.012
Hex Flat Jam 11⁄8 F p 1.500D 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.062 0.012
11⁄4 to 11⁄2 F p 1.500D 0.050 D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.125 0.012
Hex and Hex Slotted 1

⁄4 F p 1.500D + 0.015D + H p 0.875D 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.062 0.006 0.003
5
⁄16 to 5⁄8 F p 1.500D 0.015D + H p 0.875D 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.006 0.003
3
⁄4 to 11⁄8 F p 1.500D 0.050 D H p 0.875D − 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.016 0.012
11⁄4 to 11⁄2 F p 1.500D 0.050 D H p 0.875D − 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.031 0.012
Hex Jam 1
⁄4 F p 1.500D + 0.015D + H p See Table 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.062 0.006 0.003
5
⁄16 to 5⁄8 F p 1.500D 0.015D + H p See Table 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.006 0.003
3
⁄4 to 11⁄8 F p 1.500D 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.047 0.012
11⁄4 to 11⁄2 F p 1.500D 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.094 0.012
Hex Thick, and Hex 1

⁄4 F p 1.500D + 0.015D + H p See Table 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
Thick Slotted 0.062 0.006 0.003
5
⁄16 to 5⁄8 F p 1.500D 0.015D + H p See Table 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.006 0.003
3
⁄4 to 11⁄2 F p 1.500D 0.050D H p See Table 0.015D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.003
Heavy Square 1
⁄4 to 11⁄2 F p 1.500D + 0.050D H p 1.000D 0.016D + 1.373 ⴛ (Min. F ) 1.4142 ⴛ (Max.F )
0.125 0.012 − 0.030
[Note (3)]
Heavy Hex Flat 11⁄8 to 4 F p 1.500D + 0.050D H p 1.000D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.125 0.012
[Note (3)]
Heavy Hex Flat Jam 1
⁄4 to 11⁄8 F p 1.500D + 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.125 0.062 0.012
[Note (4)]
11⁄4 to 21⁄4 F p 1.500D + 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.125 0.125 0.012
[Note (4)]
21⁄2 to 4 F p 1.500D + 0.050D H p 0.500D + 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
0.125 0.250 0.012
[Note (4)]
22
ASME B18.2.2-2010
Table A-1 Formulas for Nut Dimensions (Cont’d)

Width Across Flats Nut Thickness Width Across Corners
Basic Tolerance Basic Tolerance Limits, G

Nut Type Nut Size [Note (1)] (Minus) [Note (2)] (Plus or Minus) Min. Max.
Heavy Hex and 1

⁄4 to 11⁄8 F p 1.500D 0.050D H p 1.000D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
Heavy Hex Slotted + 0.125 − 0.016 0.012
11⁄4 to 2 F p 1.500D 0.050D H p 1.000D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
+ 0.125 − 0.031 0.012
+ 0.125 − 0.047 0.012
+ 0.125 − 0.062 0.012
Heavy Hex Jam 1

⁄4 to 11⁄8 F p 1.500D 0.050D H p 0.500D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
+ 0.125 + 0.047 0.012
+ 0.125 + 0.094 0.012
21⁄4 F p 1.500D 0.050D H p 0.500D 0.016D + 1.14 ⴛ (Min. F ) 1.1547 ⴛ (Max.F )
+ 0.125 + 0.078 0.012
+ 0.125 + 0.203 0.012
+ 0.125 + 0.188 0.012
NOTES:
(1) Adjusted to sixteenths.
(2) 1⁄4 in. to 1 in. sizes adjusted to sixty-fourths. 11⁄8 in. to 21⁄2 in. sizes adjusted upward to thirty-seconds. 23⁄4 in. to 4 in. sizes adjusted
upward to sixteenths.
(3) Plus tolerance only. Minus tolerance adjusted so that minimum thickness is equal to minimum thickness of heavy hex nut.
(4) Plus tolerance only. Minus tolerance adjusted so that minimum thickness is equal to minimum thickness of heavy hex jam nut.
where
D p nominal nut size or basic diameter of the thread
F p width across flats
G p width across corners
23
ASME B18.2.2-2010
NONMANDATORY APPENDIX B
WRENCH OPENINGS FOR SQUARE AND HEX NUTS
Table B-1 specifies wrench openings for square and

hex nuts.
24
ASME B18.2.2-2010
Table B-1 Wrench Openings for Square and Hex Nuts

Allowance
Between Nominal Nut Sizes
Maximum Nut Flats Hex Flat, Hex Flat Jam,
Basic Nut and Hex, Hex Jam, Hex Heavy Square, Heavy
Size of Across Wrench Wrench Openings Machine Slotted, Hex Thick, Hex Hex Flat, Heavy Hex Flat
Wrench, Flats Jaws Tolerance Screw Square Thick Slotted, Heavy Jam, Heavy Hex, Heavy
W [Note (1)] [Note (2)] Min. [Note (2)] Max. Nuts Nuts Hex Slotted Hex Jam
5
⁄32 0.156 0.002 0.158 0.005 0.163 #0, #1 ... ... ...
3
⁄16 0.188 0.002 0.190 0.005 0.195 #2, #3 ... ... ...
1
⁄4 0.250 0.002 0.252 0.005 0.257 #4 ... ... ...
5
⁄16 0.312 0.003 0.315 0.006 0.321 #5, #6 ... ... ...
11
⁄32 0.344 0.003 0.347 0.006 0.353 #8 ... ... ...
3
⁄8 0.375 0.003 0.378 0.006 0.384 #10 ... ... ...
7
⁄16 0.438 0.003 0.440 0.006 0.446 #12, 1⁄4 1
⁄4 1
⁄4 ...
1 5 1
⁄2 0.500 0.004 0.504 0.006 0.510 ... ... ⁄16 ⁄4
9 5 5 3 5
⁄16 0.562 0.004 0.566 0.007 0.573 ⁄16 ⁄16 ⁄8 ⁄16
5 3 3
⁄8 0.625 0.004 0.629 0.007 0.636 ⁄8 ⁄8 ... ...
11 7 3
⁄16 0.688 0.004 0.692 0.007 0.699 ... ... ⁄16 ⁄8
3 7 1 7
⁄4 0.750 0.005 0.755 0.008 0.763 ... ⁄16 ⁄2 ⁄16
13 1
⁄16 0.813 0.005 0.818 0.008 0.826 ... ⁄2 ... ...
7 9 1
⁄8 0.875 0.005 0.880 0.008 0.888 ... ... ⁄16 ⁄2
15 5 9
⁄16 0.938 0.006 0.944 0.009 0.953 ... ... ⁄8 ⁄16
5
1 1.000 0.006 1.006 0.009 1.015 ... ⁄8 ... ...
11⁄16 1.063 0.006 1.068 0.009 1.077 ... ... ... 5
⁄8
11⁄8 1.125 0.007 1.132 0.010 1.142 ... 3
⁄4 3
⁄4 ...
11⁄4 1.250 0.007 1.257 0.010 1.267 ... ... ... 3
⁄4
15⁄16 1.313 0.008 1.320 0.011 1.331 ... 7
⁄8 7
⁄8 ...
17⁄16 1.438 0.008 1.446 0.011 1.457 ... ... ... 7
⁄8
11⁄2 1.500 0.008 1.508 0.012 1.520 ... 1 1 ...
15⁄8 1.625 0.009 1.634 0.012 1.646 ... ... ... 1

111⁄16 1.688 0.009 1.696 0.012 1.708 ... 11⁄8 11⁄8 ...
113⁄16 1.813 0.010 1.822 0.013 1.835 ... ... ... 11⁄8
17⁄8 1.875 0.010 1.885 0.013 1.898 ... 11⁄4 11⁄4 ...
2 2.000 0.011 2.011 0.014 2.025 ... ... ... 11⁄4
21⁄16 2.063 0.011 2.074 0.014 2.088 ... 13⁄8 13⁄8 ...
23⁄16 2.188 0.012 2.200 0.015 2.215 ... ... ... 13⁄8
21⁄4 2.250 0.012 2.262 0.015 2.277 ... 11⁄2 11⁄2 ...
23⁄8 2.375 0.013 2.388 0.016 2.404 ... ... ... 11⁄2
29⁄16 2.563 0.014 2.576 0.017 2.593 ... ... ... 15⁄8
23⁄4 2.750 0.014 2.766 0.017 2.783 ... ... ... 13⁄4
215⁄16 2.938 0.016 2.954 0.019 2.973 ... ... ... 17⁄8
31⁄8 3.125 0.017 3.142 0.020 3.162 ... ... ... 2
31⁄2 3.500 0.019 3.518 0.022 3.540 ... ... ... 21⁄4
37⁄8 3.875 0.020 3.895 0.023 3.918 ... ... ... 21⁄2
41⁄4 4.250 0.022 4.272 0.025 4.297 ... ... ... 23⁄4
45⁄8 4.625 0.024 4.649 0.027 4.676 ... ... ... 3
5 5.000 0.026 5.026 0.029 5.055 ... ... ... 31⁄4
53⁄8 5.375 0.028 5.403 0.031 5.434 ... ... ... 31⁄2
53⁄4 5.750 0.030 5.780 0.033 5.813 ... ... ... 33⁄4
61⁄8 6.125 0.032 6.157 0.035 6.192 ... ... ... 4
NOTES:
(1) Wrenches are normally marked with “Basic Wrench Size,” which corresponds to the basic (maximum, in most cases) width across flats
dimension of the respective nut. For specific requirements applicable to wrenches, refer to the appropriate ASME B107 standard, which
covers the particular wrench type.
(2) Allowance (minimum clearance) between maximum width across flats of the nut and jaws of wrench equals (0.005W + 0.001). Toler-
ance on wrench opening equals plus (0.005W + 0.004 from minimum), where W p nominal size of wrench.
25
26
B18 AMERICAN NATIONAL STANDARDS FOR BOLTS, NUTS, RIVETS, SCREWS,
WASHERS, AND SIMILAR FASTENERS
Small Solid Rivets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.1.1-1972 (R2006)

Large Rivets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.1.2-1972 (R2006)
Metric Small Solid Rivets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.1.3M-1983 (R2006)
Square, Hex, Heavy Hex, and Askew Head Bolts and Hex, Heavy Hex, Hex Flange,
Lobed Head, and Lag Screws (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.1-2010
Nuts for General Applications: Machine Screw Nuts, Hex, Square, Hex Flange,
and Coupling Nuts (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.2-2010
Metric Hex Cap Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.1M-1999 (R2005)
Metric Formed Hex Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.2M-2005
Metric Heavy Hex Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.3M-1979 (R2001)
Metric Hex Flange Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.4M-2001 (R2006)
Metric Hex Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.5M-1979 (R2006)
Metric Heavy Hex Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.6M-1979 (R2006)
Metric Heavy Hex Structural Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.7M-1979 (R2006)
Metric Heavy Hex Flange Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.3.9M-2001 (R2006)
Metric Hex Nuts, Style 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.1M-2002 (R2007)
Metric Hex Nuts, Style 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.2M-2005
Metric Slotted Hex Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.3M-1979 (R2006)
Metric Hex Flange Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.4M-1982 (R2005)
Metric Hex Jam Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.5M-2008
Metric Heavy Hex Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.4.6M-2010
Metric Flanged 12-Point Head Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.5M-2009
Fasteners for Use in Structural Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.6-2010
Metric 12-Spline Flange Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.7.1M-2002 (R2007)
Clearance Holes for Bolt, Screws, and Studs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.8-1999 (R2010)
Straightness Gage and Gaging for Bolts and Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.2.9-2010
Socket Cap, Shoulder, and Set Screws, Hex and Spline Keys (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3-2003 (R2008)
Socket Head Cap Screws (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.1M-1986 (R2008)
Metric Series Hexagon Keys and Bits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.2M-1979 (R2008)
Hexagon Socket Head Shoulder Screws (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.3M-1986 (R2008)
Hexagon Socket Button Head Cap Screws (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.4M-1986 (R2008)
Hexagon Socket Flat Countersunk Head Cap Screws (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.5M-1986 (R2008)
Metric Series Socket Set Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.3.6M-1986 (R2008)
Round Head Bolts (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.5-1990 (R2003)
Metric Round Head Short Square Neck Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.5.2.1M-2006
Metric Round Head Square Neck Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.5.2.2M-1982 (R2005)
Wood Screws (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.6.1-1981 (R2008)
Slotted Head Cap Screws, Square Head Set Screws, and Slotted Headless Set Screws (Inch Series) . . . . . . . . . . . . . . . B18.6.2-1998 (R2010)
Machine Screws and Machine Screw Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.6.3-2003 (R2008)
Thread Forming and Thread Cutting Tapping Screws and Metallic Drive Screws (Inch Series). . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.6.4-1998
Metric Thread-Forming and Thread-Cutting Tapping Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.6.5M-2000 (R2010)
Metric Machine Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.6.7M-1999 (R2010)
Wing Nuts (Inch Series). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.6.9-2010
General Purpose Semi-Tubular Rivets, Full Tubular Rivets, Split Rivets and Rivet Caps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.7-2007
Metric General Purpose Semi-Tubular Rivets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.7.1M-2007
Clevis Pins and Cotter Pins (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.8.1-1994 (R2000)
Taper Pins, Dowel Pins, Straight Pins, Grooved Pins, and Spring Pins (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.8.2-2000
Spring Pins: Coiled Type, Spring Pins: Slotted, Machine Dowel Pins: Hardened Ground,
and Grooved Pins (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.8.100M-2000 (R2005)
Cotter Pins, Headless Clevis Pins, and Headed Clevis Pins (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.8.200M-2000 (R2005)
Plow Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.9-2007
Track Bolts and Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.10-1982 (R2005)
Miniature Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.11-1961 (R2005)
Glossary of Terms for Mechanical Fasteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.12-2001 (R2006)
Screw and Washer Assemblies — Sems (Inch Series). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.13-1996 (R2008)
Screw and Washer Assemblies: Sems (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.13.1M-1998 (R2003)
Forged Eyebolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.15-1985 (R2008)
Prevailing-Torque Type Steel Metric Hex Nuts and Hex Flange Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.16M-2004 (R2009)
Serrated Hex Flange Locknuts 90,000 psi (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.16.4-2008
Nylon Insert Locknuts (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.16.6-2008
Inspection and Quality Assurance for General Purpose Fasteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.18.1-2007
Inspection and Quality Assurance for High-Volume Machine Assembly Fasteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.18.2-2009
Inspection and Quality Assurance for Special Purpose Fasteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.18.3M-1987 (R2005)
Inspection and Quality Assurance for Fasteners for Highly Specialized Engineered Applications . . . . . . . . . . . . . . . . B18.18.4M-1987 (R2005)
Inspection and Quality Assurance Plan Requiring In-Process Inspection and Controls. . . . . . . . . . . . . . . . . . . . . . . . . B18.18.5M-1998 (R2009)
Quality Assurance Plan for Fasteners Produced in a Third Party Accreditation System . . . . . . . . . . . . . . . . . . . . . . . . B18.18.6M-1998 (R2009)
Quality Assurance Plan for Fasteners Produced in a Customer Approved Control Plan . . . . . . . . . . . . . . . . . . . . . . . . B18.18.7M-1998 (R2009)
Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.21.1-2009
Lock Washers (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.21.2M-1999 (R2005)
Double Coil Helical Spring Lock Washers for Wood Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.21.3-2008
Metric Plain Washers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.22M-1981 (R2010)
Part Identifying Number (PIN) Code System for B18 Fastener Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.24-2004
Square and Rectangular Keys and Keyways. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.25.1M-1996 (R2008)
Woodruff Keys and Keyways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.25.2M-1996 (R2008)
Square and Rectangular Keys and Keyways: Width Tolerances and
Deviations Greater Than Basic Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.25.3M-1998 (R2008)
Tapered and Reduced Cross Section Retaining Rings (Inch Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.27-1998 (R2005)
Helical Coil Screw Thread Inserts — Free Running and Screw Locking (Inch Series). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.29.1-2010
Helical Coil Screw Thread Inserts: Free Running and Screw Locking (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.29.2M-2005
Open-End Blind Rivets With Break Mandrels (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.30.1M-2000 (R2005)
Metric Continuous and Double-End Studs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.31.1M-2008
Continuous and Double-End Studs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.31.2-2008
Threaded Rods (Inch Series). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.31.3-2009
Threaded Rod (Metric Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B18.31.4M-2009
The ASME Publications Catalog shows a complete list of all the Standards published by the Society. For a complimentary catalog, or the latest
information about our publications, call 1-800-THE-ASME (1-800-843-2763).
ASME B18.2.2-2010
M04310

Asme B 18.2.2

Uploaded by

Copyright:

Available Formats

Asme B 18.2.2

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Asme B 18.2.2

Uploaded by

Copyright:

Available Formats

+7 (495) 133-39-24

ДАННЫЙ МАТЕРИАЛ ПРЕДОСТАВЛЕН ИСКЛЮЧИТЕЛЬНО ДЛЯ ОЗНАКОМЛЕНИЯ

Nuts for General

Nuts for General

Three Park Avenue • New York, NY • 10016 USA

ASME is the registered trademark of The American Society of Mechanical Engineers.

No part of this document may be reproduced in any form,

The American Society of Mechanical Engineers

STANDARDS COMMITTEE OFFICERS

STANDARDS COMMITTEE PERSONNEL

Nuts for General Applications: Machine Screw Nuts, Hex,

1 INTRODUCTION ASME B18.12, Glossary of Terms for Mechanical

Table 1-1 Dimensions of Square and Hex Machine Screw Nuts

Machine Screw Nuts [Note (1)]

Width Across Corners

Table 1-2 Dimensions of Small Pattern Hex Machine Screw Nuts

Table 2 Dimensions of Square Nuts

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

11⁄8 1.1250 111⁄16 1.631 1.688 1.859 1.949 1 0.970 1.030 5

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Table 4 Dimensions of Hex Nuts and Hex Jam Nuts

Maximum Runout of Bearing

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Table 5 Dimensions of Hex Slotted Nuts

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Table 6 Dimensions of Hex Thick Nuts

Maximum Runout of Bearing

Basic Major Width Across Flats, F Corners, G Specified Proof Load

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Table 7 Dimensions of Hex Thick Slotted Nuts

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Table 8 Dimensions of Heavy Square Nuts

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

GENERAL NOTE: For additional requirements, refer to section 3, General Data.

Maximum Runout of Bearing

Table 11 Dimensions of Heavy Hex Slotted Nuts

Hex Flange Nuts

Table 13 Dimensions of Hex Coupling Nuts

Basic Major Width Across

Table 13 Dimensions of Hex Coupling Nuts (Cont‘d)

Table I-1 Dimensions of Slot Gages and Gage Pins

Table A-1 Formulas for Nut Dimensions

Basic Tolerance Basic Tolerance Limits, G

Hex and Hex Slotted 1

Hex Thick, and Hex 1

Table A-1 Formulas for Nut Dimensions (Cont’d)

Basic Tolerance Basic Tolerance Limits, G

Heavy Hex and 1

Heavy Hex Jam 1

Table B-1 specifies wrench openings for square and

Table B-1 Wrench Openings for Square and Hex Nuts

15⁄8 1.625 0.009 1.634 0.012 1.646 ... ... ... 1

Small Solid Rivets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B18.1.1-1972 (R2006)

You might also like