25 February 1987
SUPERSEDING
ANSI/ASME B 1 8 -3.1EI-1986
21 June1982
ACCEPTANCE NOTICE
T h i s non-Governmentdocument
was adoptedon 25 February1987,and
is
approved for u s e by t h e DoD. The i n d i c a t e di n d u s t r yg r o u ph a sf u r n i s h e d
the c l e a r a n c er e q u i r e d by e x i s t i n gr e g u l a t i o n s .C o p i e s
of the document
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Forms
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C o n t r a c t o r sa n dI n d u s t r yg r o u p sm u s to b t a i nc o p i e sd i r e c t l yf r o m :
The
AmericanSociety of M e c h a n i c a lI n g i n e e r sU n i t e dE n g i n e e r i n gC e n t e r ,3 4 5
E. 4 7 t hS t r e e t , New York, NY 10017 o r TheAmerican
N a t i o n a lS t a n d a r d s
New York, NY 10018.
I n s t i t u t e , 1430
Broadway,
T i t l e of Document:
Screw,
Socket
Cap,
Head-Metric
Series
Document Number:
ASME/.ANSI B18.3.1M-1986
Date o S
f p e c i f i cI s s u eA d o p t e d :
29 August
1986
R e l e a s i Inngd u s t r y
The American S o c i e t y Mechanical
of
Engineers
Group:
NOTICE:
When
r e a f f i r m a t i o n , amendment, r e v i s i o n , or c a n c e l l a t i o n of
t h i s s t a n d a r d is i n i t i a l l y p r o p o s e d , t h e i n d u s t r y g r o u p r e s p o n s i b l e f o r
m i l i t a r y c o o r d i n a t i n g a c t i v i t y of t h e
thisstandardshallinformthe
p r o p o s e dc h a n g ea n dr e q u e s tp a r t i c i p a t i o n .
Custodians:
AR
Army
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AS
Air F o r c e
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MilitaryCoordinatingActivity:
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( P r o j e c t 5305-1672)
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Review A c t i v i t i e s :
Army
AT, AV, CR,
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IS
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EA, MI
User A c t i v i t i e s :
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COPYRIGHT American Society of Mechanical Engineers
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1-1
A AN M E R I C A N A T I O N A SL T A N D A R D
Socket Head Cap Screws
(Metric Series)
'6-2
ASMEIANSI B1 8.3.1 "1986
Government Key Words:
Screw, Cap, Socket Head - Metric
. I
(REVISION OF ANSVASME B18.3.1M-1982)
i
- .
SPONSORED ANDPUBLISHED
T H EA M E R I C A NS O C I - E T Y
United
Engineering
Center
OF
M E C H A N I C A LE N G I N E E R S
3 4 5 East 47th
Street
New
York,
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COPYRIGHT American Society of Mechanical Engineers
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BY
N. Y. 1 O 0 1 7
Date of Issuance: February 15, 1987
This Standard will be revised when the Society approves the issuance of a new edition.
There will be no addenda or written interpretations of the requirements of this Standard
issued to thisEdition.
This code or standard was developed under procedures accredited as meeting the criteria for
American National Standards. The Consensus Committee that approved the code or standard was
balanced t o assure that individuals from competentand concerned interests have had an opportunity
tq participate. The proposed code or standard was made available for public review and comment
which 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 t o the validity of any patent rights asserted in
connection with any items mentioned in this document, and does not undertake t o insure anyone
utilizing a standard against liability forinfringement of any applicableLetters Patent, nor assume any
such liability.Users of a code or standard are expresslyadvised that determination of the validityof
any such patentrights, and the risk of infringement of suchrights, is entirely their own responsibility.
Participation by federal agency representative(s) or person(s1 affiliated with industry is nott o be
interpreted as government or industryendorsement of this code or standard.
ASME accepts responsibility for only those interpretations issued in accordance with governing
ASMEproceduresandpolicieswhich
preclude the issuance ofinterpretations by individual
volunteers.
No part of thisdocument may bereproduced in any form,
in an electronic retrieval system or otherwise,
without theprior written permission of the publisher.
Copyright 0 1987 by
THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
All Rights Reserved
Printed in U.S.A.
? Society of Mechanical Engineers
COPYRIGHT American
Licensed by Information Handling Services
FOREWORD
(This Foreword is not part of ASME/ANSI B18.3.1hA-1 986.)
s.&
American National Standards CommitteeB18 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 and, as of
October 6, 1969, the American National Standards Institute)with the Society of Automotive Engineers and the American Society of Mechanical Engineers as joint sponsors.
Subcommittee No.9 was established in April 1929 to undertake development and oversee
maintenance of standards covering socket head cap screws and set screws. In line with a general realignment of the Subcommittee structure onApril 1 , 1966, Subcommittee 9 was redesignated Subcommittee 3. Over the intervening years this activity has produced several
versions of American National Standardscovering inch series socket cap, shoulder, andset
screws bearing the B18.3 designation.
B18, SubAt theDecember-4, 1974 meeting of American National Standards Committee
committee 3 was assigned the task of preparing standards for metric series socket screw
products paralleling that containedin the latestANSI B18.3 document. The Subcommittee
was also instructed to continue coordinating thatactivity with the International Standards
Organization, IS0 Technical Committee 2, and Working Group 3, and to the extent possible, keep the proposalsfor metric standards underdevelopment in conformance with agreements reached therein.
At the February19,1975 meeting of Subcommittee 3, it was agreed that thefollowing basic principles be considered in developing the metric version of the standard.
(a) To assure consumers continuity of performance integrityconsistent with inch socket
screw products, the metric standards should maintain the
same quality levels as their inch
counterparts.
(b) To facilitate and expedite the processing, acceptance, and adoptionof the metric versions, proposals for the
various product categories should be prepared as separate andcomplete product standards.
(c) To promote understanding and assimilation during the transition to metric, the dimensional symbols, designations, terminology, and basic formats of the metric standards
should be kept similar to those used in the ANSI B18.3 document.
In line with the foregoing, itwas also agreed that a proposal covering metric series socket
head cap screws based on the socket screw industry document, recognizing only alloy steel
screws conforming to IS0
property class 12.9 and containing data
paralleling that under development by ISO/TC2/WG3 for updating the IS0R861 standard, becirculated for Subcommittee consideration. It was noted that due todiverse methods of tolerancing, several
noncritical dimensions such as head diameter, head height, key engagement, and wall thickness reflected minor differences from the I S 0 values at their extremes. Consequently, a
draft standard documenting these dimensional differences in an appendix and denoting
that screws would be considered both functional andacceptable to these dimensions during
the transitionperiod was prepared and adoptedby Subcommittee 3. Letter ballot of the initial proposal to Committee B18 resulted in extensive comments. A redraft incorporating
iii
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..
-
. .
resolutions of these comments, changes appearing inI S 0 4762-1977, plus contemplated revisions thereto, and addition of government procurement data, was accepted by the B18
Committee inSeptember 1977. After approvalby the sponsororganizations, the proposed
standard was submitted to the American National Standards Institute and granted
recognition as an American National Standard on April 5 , 1978.
Updating of the standardwas initiated at the May1979 meeting of Subcommittee 3, and
discussions held over two ensuingmeetings resulted in agreement that the document should
be revised to incorporate changes to the tolerance on length, the grip, body lengths, and
thread documentation; add dimensions for drilled head screws as an appendix; and eliminate theextensive data pertaining to nondimensional and performance requirements in favor of referencing the ASTM A 574M specification which had been releasedin the interim.
A proposal embodying these changes álong with extensive editorial refinements was prepared. Subsequent to Subcommittee acceptance, the proposalwas approved by letter ballot
to American National Standards Committee B18 and duly submitted for approvalby the
sponsor organizations and the
American National Standards Institute. The
revision was officially designated an American National Standard on February 18, 1982.
A periodicreview of the standard, undertakenby the Subcommittee in 1985, resulted in
agreement that the standardbe revised to reflect interchangeability with screws made to IS0
documents and to incorporate by reference the new ASTM documents for the appropriate
mechanical, chemical, and testing requirements of metric socket head cap screws. A proposal containing these changes, as well as editorial corrections, was prepared for and balloted by letter ballotto ASME Committee B18. Following approval by ASME, the proposal
was submitted to the American National Standards Institute anddesignated an American
National Standard on August 29, 1986.
r
!
iv
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Society of Mechanical Engineers
.
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f
Y,
ASME STANDARDS COMMITTEE B18
Standardization of Bolts, Nuts, Rivets, Screws, Washers, and Similar Fasteners
(The following is the roster
of the Committee atthe timeof approval of this Standard.)
OFFICERS
J. B. Levy, Chairman
H. W. Ellison, Vice Chairman
E. Schwartz, Vice Chairman
R. W. McGinnis, Secretary
COMMITTEE PERSONNEL
AMERICAN SOCIETY OF AGRICULTURAL ENGINEERS
E. R. Friesth, Don E. Williams Co., Rock Island, Illinois
AMERICAN SOCIETY OF MECHANICAL ENGINEERS
A. R. Machell, Webster, New York
K. E. McCullough, SPS Technologies Inc., Jenkintown, Pennsylvania
ENGINE MANUFACTURERS ASSOCIATION
G. A. Russ, Cummins Engine Co., Columbus, Indiana
FARM & INDUSTRIAL EQUIPMENT INSTITUTE
D. A. Clever, Deere & Co., Moline, Illinois
HAND TOOL INSTITUTE
R. B. Wright, Wright Tool Co., Barberton, Ohio
INDUSTRIAL FASTENERS INSTITUTE
D.J. Broomfield, Illinois Tool Works Inc., Elgin, Illinois
D. A. Garrison, Russell, Burdsall &Ward Corp., Rock Falls, Illinois
R. M. Harris, Bethlehem Steel Corp., Lebanon, Pennsylvania
D. Littel, Greensburg, Pennsylvania
J. C. McMurray, Alternate, Russell, Burdsall & Ward Inc., Cleveland, Ohio
J. S.Orlando, Chicago, Illinois
E. Sterling, Emhart Corp., Cambellsville, Kentucky
J. A. Trilling, Holo-Krome Co., West Hartford, Connecticut
S.Vass, Lake Erie Screw Corp., Cleveland, Ohio
C. J. Wilson, Industrial Fasteners Institute, Cleveland, Ohio
METAL CUTTING TOOL INSTITUTE
D. Emanuelli, TRW-GreenfieldTap & Die, Greenfield, Massachusetts
NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION
J. B. Levy, Scotia, New York
W. F. Montavon, Alternate, National Electric Manufacturers.Association, Washington, D.C.
F. F. Weingruber, Westinghouse Electric Corp., Pittsburgh, Pennsylvania
NATIONAL FASTENERS DISTRIBUTORS ASSOCIATION
J. F. Sullivan, Accurate Fasteners, Inc., South Boston, Massachusetts
V
COPYRIGHT American Society of Mechanical Engineers
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ASME B118*3.LM 86
m
0 7 5 7 6 7 0 00434115 7 W
SOCIETY OF AUTOMOTIVE ENGINEERS
H. W. Ellison, General Motors Corp., Warren, Michigan
R. S.Piotrowskl, Mack Trucks Inc., Allentown, Pennsylvania
TUBULAR & MACHINE INSTITUTE
R. M. Byrne, Trade Association Management Inc., Tarrytown, New York
J. G. Zeratsky, National Rivet& Manufacturer CÖ., Waupun, Wisconsin
U. S.. DEPARTMENT OF THEARMY
M. E. Taylor, U. S. Army Armament, Munitions & Chemical Command, Dover, New Jersey
A. Herskovitz, Alternate, U. S.Army Armament, Munitions & Chemical Command, Dover, New Jersey
J. E. Long, Alternate, U. S.Tank Command, Warren, Michigan
U. S, DEPARTMENT OF DEFENSE
E. Schwartz, Defense Industrial Supply Center, Philadelphia, Pennsylvania
L. Pieninck, Alternate, Defense Industrial Supply Center, Philadelphia, Pennsylvania
U. S. DEPARTMENT OF THE NAVY
J. E. Hass, Department of the Navy; Washington, D.C.
M. S. Orysh, Alternate, Department of the Navy, Philadelphia, Pennsylvania
INDIVIDUAL MEMBERS
A. R. Breed, Lakewood, Ohio
R. A. Flor, Chrysler Corp., Detroit, Michigan
G. A. Gobb, Ford Motor Co,, Dearborn, Michigan
F. E. Greves, F. E. Graves Associates, Fairfield, Connecticut
J. J. Naesset, Clark Equipment Co., Battle Creek, Michigan
J. F. Nagy, Ford Motor Co., Dearborn, Michigan
PERSONNEL OF SUBCOMMITTEE 3 - SOCKET HEAD CAP AND SET SCREWS (BI 8)
J. A. Trilling, Chairman, Holo-Krome Co., West Hartford, Connecticut
R. M. Byrne, U. S. Screw Service Bureau, White Plains, New York
A. Herskovitz, U. S. Army Armament R & D Command, Dover, New Jersey
K. E. Mcdullough, SPS Technologies, Jenkintown, Pennsylvania
L. Pieninck, Defense Industrial Supply Center, Philadelphia, Pennsylvania
F. F. Weingruber, Westinghouse Electric Corp., Pittsburgh, Pennsylvania
C. J. Wilson, Industrial Fasteners Institute, Cleveland, Ohio
vi
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CONTENTS
...............................................................
.........i . . .................................
iii
v
..........................................................
..........................................
.......................
1
2
11
Foreword
StandardsCommittee Roster..
1
2
3
General..
Dimensional Characteristics
Materials, Processing, and Mechanical Properties.
Figures
..................................................
..................................................
Socket
1
Edge Detail
2CompoundHole
for Checking Runout Between Thread,
Body, andHead
Tables
1
2
3
4
5
6A
6B
7
.........................
................................
...........................
.............................
......................................................
Dimensions of Metric Socket Head Cap Screws.
Dimensions of Metric Hexagon Sockets
Dimensions of Metric Spline Sockets.. .................................
Dimensions of Metric Hexagon Socket Gages
Dimensions of Metric Spline Socket Gages.
Body and Grip Length Dimensions for Metric Socket Head
Cap Screws.
Thread Lengths for Determining Body and Grip Lengths on
Screws Beyond Diameters and Lengths Tabulated in Table 6A. ..........
Functional Limits for Runout of Head, Body, andThread on
Metric Socket Head Cap Screws..
...................................
Appendices
I
Drill andCounterbore Sizes for Metric Socket Head Cap Screws.
II
Dimensions of Drilled Head Metric Hexagon Socket Head
Cap Screws..
III Formulas for Dimensions
:
IV I S 0 Dimensional Variations Due to Tolerance Deviations.
V
GovernmentStandard Items andPart Numbering System.
VI Dimensions of Metric Threads f m Small Sizes of Socket
Screw Products
..........
.....................................................
............................................
... ............
................
...................................................
vii
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/
\
5
11
3
5
5
6
7
9
10
12
13
15
16
17
18
21
ASMElANSl B1 8.3.1M-I986
4
SOCKET HEAD CAP SCREWS (METRIC SERIES)
4"
=!
L.
'
i
-23
1 GENERAL
1.4 Options
1.IScope
Options, where specified, shall be at the discretion
of the manufacturer unless agreed upon otherwise by
manufacturer and purchaser.
1.1.1 This Standard contains
complete general and
dimensional data for metric series hexagon socket
head cap screws in sizes from 1.6 mm to 48 mm and for
metric series spline socket head cap screws in sizes
from 1.6 mm to 8 mm recognized as American National Standard, Also included are appendices covering drill and counterbore sizes (Appendix I), drilled
head dimensions (Appendix II), formulas for dimensions (Appendix III), IS0 dimensional variations (Appendix IV), part numbering system and preferred sizes
for government use (Appendix V), and threaddimensions (Appendix VI).
1.5 Responsibility for Modification
The manufacturer shall not be held responsible for
malfunctions of product dueto plating or other modifications, when such plating or modification is not accomplished under his control or direction.
1.6 Terminology
1.1.2 The inclusion of dimensional data in this
Standard is not intended to imply that all of the products described are stock production sizes. Consumers
should consult with manufacturers concerning lists of
stock production sizes.
For definitions of terms relating to fasteners or to
component featuresthereof used in this Standard, refer to ANSI B18.12, Glossary of Terms for Mechanical Fasteners.
1.2 Interchangeability With Screws Made to IS0
Documents' .
1.7 Designation
Metric socket head cap screws conforming to this
Standard shall bedesignated by the following data in
the sequence shown:
(a) Specification (ASME/ANSI document) number followed by a dash;
(b) Nominal size of screw;
(c) Thread pitch, preceded by x ;
(d)Nominal screw length, preceded by X ;
(e) Product name. If desired, the product name
may be abbreviated SHCS.
u> Material and property class. Alloy steel screws
shall be supplied to property class 12.9 as specified in
ASTM A 574M. For corrosion-resistant steel screws,
the property class and material requirements shall be
as specified in ASTM F 837M (see para. 3.1).
(g) Drive. Unless specified otherwise, the socket
shall be hexagon.
Screws made to this Standard arefunctionally interchangeable with screwsthat conform to International
Standard I S 0 4762-1977. Minor variations indimensions due to diverse tolerancing practices are documented in Appendix IV.
1.3 Dimensions
All dimensions in this Standard are given in millimeters (mm) and apply before plating unless stated
otherwise.
'IS0 documents areavailable for purchase from the American National StandardsInstitute, 1430 Broadway, New York, N.Y. 10018.
1
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ASME B l 1 8 - 3 ~ 3 M
86
13759670 0043438 9
SOCKET HEAD CAP SCREWS (METRIC SERIES)
ASMElANSl 818.3.1 M-1986
screw being held within a distance equal to onescrew
diameter from the underside of head but beyond the
underhead fillet.
(h) Protective finish, if required (see para. 3.3).
Examples:
B18.3.1M -6
I
+:ber
I
X
1 X 20 Hexagon Socket Head Cap Screw, Alloy
Steel
\ \
\
\z?f-y>
B18.3.1M - 10 X 1.5
B18.3.1M - 8 X 1.25
X
X
'
2.1.6 Underhead Fillet. For all lengths of screws
the form of the fillet at junction of head and shank
shall be optional within the following provisions. The
'fillet shall be a smooth and continuous
concave curve
fairing into the bearing surface within the limits for
diameter B , with a juncture radius of not less than F,
and blending into the shank at a distance from the
head not exceeding E, as determined at the basic screw
diameter D.
ProductName
or Abbreviation
40 SHCS, Alloy Steel Zinc Plated
30 Spline SHCS Al-70.
1.8 Part Numbering System
For users who needa definitive part numbering system, one is suggested in Appendix V.
2.2 Sockets
2 DIMENSIONAL CHARACTERISTICS
2.2.1 Socket Type. Hexagon sockets shall be supplied, unless spline sockets are specified by the customer for screw sizes in which they are available.
The following requirements supplement the dimensional data presented in Tables 1, 2, and 3 and shall
apply to the respective features of screws.
2.2.2 Socket Size. Sockets shall be nominal size J
for hexagon sockets and Mfor spline sockets specified
in Table 1 for thecorresponding screw size, and shall
conform to the dimensions given in Tables 2 and 3, respectively, as determined by gaging or measurement in
accordance with para. 2.2.4,
2.1 Heads
2.1 .I Head Diameter. Heads may beplain or
knurled at the optionof the manufacturerunless specified otherwise by the customer. For knurled screws
the maximum head diameter shall be measured across
the topsof the knurland the minimum head diameter
shall be the diameter of the unknurled portion. The
minimum head diameter should be measured just
above the radius or chamfer at the bottomedge of the
head, For nominal screw sizes 5 mm and larger, the
heads shall be marked as specifed in para. 3.2.
z
"
2.2.3 KeyEngagement. The key engagement
depth shall conformto the minimum values specified
for TinTable 1,as determined by gaging or measurement in accordance with para. 2.2.4.
2.2.4 Socket Gaging. Acceptability of hexagon
sockets of nominal socket sizes up to and including 24
mm and all spline sockets shall be ascertained by the
use of the socket gages specified in Tables 4 and 5 , respectively. The sockets shall allow the GO member of
the gage to enter freely to the minimum key engagement depth. The NOT GO gage member shall be permitted to enter only to a depth equivalent to 10% of
the nominal socket size for the 1.5 nominal size and
7.5% of the nominal socket size for larger sockets.
Suitability of hexagon sockets of nominal sizes larger
than 24 mm shall be determined by direct measurement.
To determine the acceptability of sockets in plated
products after plating, a GO gage identical in design
and tolerances to thatshown in Tables 4 and 5 for hexagon or spline sockets, respectively, except having
minimum dimensions equal to the nominal size, shall
be employed.
2.1.2 Top of Head. The top of head, excluding
socket, shall be flat and chamfered or radiused at the
periphery. The .length of the chamfer or rounding
measured on the side of the head shall not exceed the
tabulated value for S given in Table l .
2.1.3 Edge of Head. The edge between the bearing
surface and the side of the head
may be broken
(rounded or chamfered), If broken, the radius or
chamfer measured along the bearing surfaceshall not
exceed the vaiues'listed for k in Table l .
2.1.4 Bearing Surface. The plane of the bearing
surface shall be perpendicular to the axis of the screw
within a maximum deviation of 1 deg.
-
:
2.1.5 Head Concentricity.The head shall be con.
centric with the axis of the screw shank within an
amount equal to 2% of the basic screw diameter or
0.15 mm, whichever is greater, FIM (Full Indicator
Movement). Concentricity shall be measured with the
2.2.5 Edge of Socket.The edge at the junctionof
the socket with the top of .the head may be broken
(rounded or chamfered) as depicted in Fig, 1. provided
2
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COPYRIGHT American Society of Mechanical Engineers
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3.00
4.00
5.00
M3
M4
M5
M6 x 1
M8 x 1.25
Ml0
x 1.5
6.00
8.00
10.00
1.60
2.00
2.50
Ml.6
x 0.35
M2 x 0.4
M2.5
x 0.45
x 0.5
x 0.7
x 0.8
Max.
Body
Diameter
Nominal
Size and
Thread
Pitch
D
M
-t-
1
5.82
7.78
9.78
2.86
3.82
4.82
1.46
1.86
2.36
Min.
b
+-A
A
Head
Diameter
1
5.32
6.80
8.27
9.74
12.70
15.67
10.00
13.00
16.00
2.87
3.65
4.33
Min.
5.50
7.00
8.50
3.00
3.80
4.50
Max.
+
J
TABLE 1
-
b
+-A
-
6.00
8.00
10.00
3.00
4.00
5.00
1.60
2.00
2.50
Max.
Head
Height
H
5.85
7.83
9.81
2.89
3.88
4.86
1.52
1.91
2.40
Min.
DIMENSIONS
S-B
--I
2.5.4
0.60
0.80
1 .oo
0.30
0.40
0.50
0.16
0.20
0.25
Max.
Chamfer or
Radius
5.0
6.0
8.0
2.5
3.0
4.0
1.5
1.5
2.0
lexagor
Socket
Size
J
5.486
7.391
. . .
2.819
3.378
4.648
1.829
1.829
2.438
Spline
Socket
Size
M
3.00
4.00
5.00
1.50
2.00
2.50
0.80
1 .oo
1.25
Min.
IEngagement
Key
T
2.28
3.20
4.00.
1.02
1.52
1.90
0.54
0.68
0.85
Min.
Wall
Thickness
G
OF METRIC SOCKET HEAD CAP SCREWS
Para.
6.8
9.2
11.2
3.6
4.7
5.7
2.0
2.6
3.1
Max.
Transition
Diam.
B
(Table
6.5
8.8
10.8
3.2
4.4
5.4
31.8
2.2
2.7
Min.
Fillet
1 continues
0.68
1.02
1.02
0.51
0.60
0.60
0.34
0.51
0.51
Max.
Transition
Length
T
Underhead
E
0.25
0.40
0.40
0.10
0.20
0.20
0.10
0.10
0.10
Min.
K
page)
0.20
0.20
0.20
0.13
0.13
0.13
0.08
0.08
0.08
Max.
Chamfer or
Radius
on next
Juncture
Radius
F
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P
x 3.5
x 4
x 4.5
x 5
M36
M42
M48
NOTE:
(1) The
14
See Para.
36.00
42.00
48.00
20.00
24.00
30.00
12.00
14.00
16.00
Max.
2.4.2
Body
Diameter
35.61
41.61
47.61
19.67
23.67
29.67
11.73
13.73
15.73
Min.
A
54.00
63.00
72.00
30.00
36.00
45.00
18.00
21 .oo
24.00
53.37
62.31
71.27
29.53
35.48
44.42
17.63
20.60
23.58
Min.
designs.
36.00
42.00
48.00
20.00
24.00
30.00
12.00
14.00
16.00
Max.
Head
Height
H
DIMENSIONS
for use in new
2.1.1
Head
Diameter
Max.
x 2 mm size is not recommended
x 2.5
M20
~24
M30
x 3
x 1.75
x 2 (1)
x 2
Ml2
Ml4
Ml6
Nominal
Size and
Thread
Pitch
D
TABLE 1
2.5.4
2.6
35.64
41.61
47.58
19.73
23.70
29.67
11.79
13.77
15.76
Min.
2.1.2
3.60
4.20
4.80
2.00
2.40
3.00
1.20
1.40
1.60
Max.
fer or
Radius
s
2.2.2
27.0
32.0
36.0.
17.0
19.0
22.0
10.0
12.0
14.0
.
.
.
.
.
.
2.2.2
.
.
.
.
.
.*.
.
.
.
.
.
Nom.
.
.
.
e
.
.
.
.
Spline
Socket
Size
lexagon
Socket
Sire
Nom.
M
J
2.2.3
18.00
21 .oo
24.00
10.00
12.00
15.00
6.00
7.00
8.00
Min.
14.40
16.80
19.20
8.00
9.60
12.00
4.80
5.60
6.40
Min.
Wall
Thickness
Key
Ingagemant
G
T
B
39.4
45.6
52.6
22.4
26.4
33,4
14.2
16.2
18.2
Max.
Min.
2.1.6
Underhead
.
38.0
44.4
51.2
21.6
25.6
32.0
13.2
15.2
17.2
Fillet
E
Transition
Length
2.89
3.06
3.91
2.04
2,04
2.89
1.87
1.87
1.87
Max.
I
Transition
Diam.
OF METRIC SOCKET HEAD CAP SCREWS (CONT’D)
Para.
-Para.
’
1 .oo
1.20
1.60
0.80
0.80
1.00
0.60
0.60
0.60
Min.
Juncture
Radius
F
2.1.3
0.25
0.25
0.25
fer or
Radius
K
J
_
r-
SOCKET HEAD CAP SCREWS (METRIC SERIES)
-)1 T
ASME/ANSI B18.3.1M-1986
Table 1
(a) Forged Socket
4 L D e p t h of chamfer
Width of overcut
(para. 2.2.6)
or rounding
T
It- Table 1
FIG. 1
SOCKET EDGE DETAIL
of flat
M
T+-+Table
1
(b)Broached Socket
4
4"
t
L
c
TABLE 2 DIMENSIONS OF METRIC
HEXAGON SOCKETS
i
Nominal
Hexagon
Socket
Size
1.5
2
2.5
I
J
C
Across
Socket
WidthFlats
Socket Width
Across Corners
1.545
2.045
2.560
Min.
Min.
1,520
2,020
2.520
1.73
2.30.
2.87
TABLE 3
DIMENSIONS OF METRIC
SPLINE SOCKETS
M
Socket
Major
Diameter
N
P
Socket
Minor
Diameter
Width
of
3
4
5
3.071
4.084
5.084
3.020
4.020
5.020
3.44
4.58
5.72
Nominal
Spline
Socket
Size
6
8
10
6.095
8.1 15
10.127
6.020
8.025
10.025
6.86
9.1 5
11.50
1.829
2.438
2.819
1.8796 1.8542 1.6256 1.6002
2.4892 2.4638 .2.0828 2.0320
2.9210
2.4384 2.4892
12
14
17
12.146
14.159
17.216
12.032
14.032
17.050
13.80
16.09
19.56
3.378
4.648
5.486
3.4798 3.4290 2.9972 2.9464
4.7752 4.7244 4.1402 4.0894
5.6134 5.5626 4.8260
4.7752
19
22
24
19.243
22.319
24.319
19.065
22.065
24.065
21.87
25.31
27.60
7.391
7.5692 7.5184
27
32
36
27.31 9
32,461
36.461
27.065
32.080
36.080
31 .O4
36.80
41.38
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
~
Max.
Min.
Max.
,
Tooth
Min.
2.8702
6.4516 6.4008
GENERAL NOTE:
The tabulated dimensions represent direct metric conversions
of the equivalent inch size spline sockets shownin ASME/ANSI
818.3, Socket Cap, Shoulder, and Set Screws (Inch Series).
Therefore, the spline keys and bits showntherein are applicable
for wrenching the corresponding size metric spline sockets.
SOCKET HEAD CAP SCREWS (METRIC SERIES)
ASMElANSl BI 8.3.1 M-I986
r
PAI
D
1
y Standard handle
NOT GO
member
t
7"
L Mark with size
Truncate hexagon
t o dimension
LF
L Mark with size
(E max.)
( A min.)
Truncate hexagon
t o dimension
7
FD-1
5 deg. chamfer optional
GO Member
Optional
Construction
for Small Sizes
TABLE 4
"
i
-1
Nominal
Hexagon
Socket
Size
DIMENSIONS
NOT GO Member
Construction
for Small Sizes
OF METRIC HEXAGON SOCKET GAGES
A
B
C
GO Gage
Width Across
Flats
GO Gage
Width Across
Corners
GO
Gage
Length
Usable
NOT GO
Length
Width
Min.
Min.
F
I
NOT GO
Gage
Thickness
I
Max.
Min.
...
..,
,.,
...
...
Max.
Min.
5.0
5.0
7.0
1.545
2.045
2.560
1.543
2.043
2.554
7.0
7.0
7.0
7.0
7.0
7.0
3.071
4.084
5.084
3.066
4.079
5.079
1.ao
2.30
6.855
9.145
11.495
8.0
8.0
12.0
12.0
16.0
20.0
6.095
8.115
10.1 27
6.091
8.1o9
10.122
2.80
3.80
4.80
2.75
3.75
4.75
13.800
16.090
19.560
13.795
16.085
19.555
12.0
12.0
19.0
24.0
28.0
34.0
12.146
14.159
17.216
12.141
14.154
17.211
5.75
6.75
8.10
5.70
6.70
8.05
21.870
25.310
27.600
21.865
25.305
27.595
19.0
22.0
25.0
38.0
44.0
48.0
19.243
22.31 9
24.319
19.238
22.314
24.314
Max.
Min.
Max.
Min.
1.5
2.0
2.5
1.523
2.023
2.525
1.520
2.020
2.520
1.730
2.300
2.870
1.725
2.295
2.865
5.0
5.0
7.0
3.0
4.0
5.0
3.025
4.025
5.025
3.020
4.020
5.020
3.440
4.580
5.720
3.435
4.575
5.71 5
6.0
8.0
10.0
6.025
8.030
10.030
6.020
8.025
10.025
6.860
9,150
11.500
12.0
14.0
17.0
12.037
14.037
17.055
12.032
14.032
17.050
19.0
22.0
24.0
19.070
22.070
24.070
19.065
22.065
24.065
-
...
...
...
1.75
2.25
9.10 9.05
10.50 10.45
11.50 11.45
-
G
NOT GO Gage
Corners
Width
Across
Max.
Min.
1.68
2.23
2.79
1.66
2.21
2.77
3.35
3.33
.
. ..
...
...
,..
. ..
...
...
...
...
,.
...
...
I
...
...
...
...
...
...
s..
...
...
...
GENERAL NOTES:
(a) Gages shall be madefrom steel, hardened andtempered t o a hardness of HRC 60 minimum. They shall be thermally stabilized and
given suitable surface treatment to obtain maximum abrasion resistance.
(b) The form of hexagonal gage members shall be within thetolerance zone specified. See ANSI Y14.5M. Engineering Drawing and
Related Documentation Practices, Dimensioning and Tolerancing.
(cl The surface roughness on hexagonal flats shall be 0.2 pm (arithmetical average) ma$mum.See ANWASME 846.1, Surface
Texture.
(d) The gage handles shall conform t o ANSI 647.1, Gage Blanks.
6
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
7..
ASMElANSl B18.3.1M-1986
SOCKET HEAD CAP SCREWS (METRIC SERIES)
y
\i
I
tL
Standard handle
GO . _ _ _ . _ _ _NOTGO
_
Mark with size
( A min.)
E
GO member
NOT
-q
r
I +
"
Mark with size
(Gbasic)
GO member
T
4
k
d
e
g
i
.
Detail of GO Gage Member
TABLE 5
DIMENSIONS OF METRIC SPLINE SOCKET GAGES'
I
I
Nominal
Number
Spline
of
Socket
Teeth
Size
I
A
GO Gage Major
Diameter
Min.
Max.
I
B
C
Minor
Diameter
Max.
Min.
Max.
6
1.5926 1.8415 1.8466
6 2.0193
2.4562
0.5664 0.5715
1 2.3825 2.0244 2.451
2.3825 2.8626
2.4308 2.8575
3.378
4.648
5.486
7.391
6
6
6
2.3825
4.7625
4.7117
6
6.3932
7.5057
6.3500
D
E
F
G
GO Gage
NOT GO
GO Gage GO
Gage Space GO Gage Gage
Shoulder
Diameter
Length
Length Diameter
Width
1.829
2.438
2.81 9
4.7168
5.5550
7.5103
I
Min.
Min.
0.4140
k0.0508
Min.
0.4191
1.5875 1.5875
1.a542 4.7498
2.4892
6.3500
2.4257 0.6426 0.6477
6.3500
6
0.7747 2.4163 2.4214
2.9388
2.9337
0.9982 1.0033
4.0767
4.0818
4.7625
6.3881
Basic
1.6256
2.0828
2.489'2
2.8702
2.9972
0.7696
3.4544 6.3500
4.1402
4.7625 9.5250
1.2776
5.5550 1.2827
11 .O998
4.7625
4.7676
4.8260
1.7348
7.5387 1.7399
15.8750
6.451 6
GENERAL NOTES:
(a) Gages shall be made from steel, hardened and tempered t o a hardness of HRC 60 minimum. They shall be thermally stabilized and
given suitable surface treatment t o obtain maximum abrasion resistance.
(b) The form of hexagonal gage members shall be within the tolerance zone specified. See ANSI Y14.5M. Engineering Drawing and
Related Documentation Practices, Dimensioning and Tolerancing.
(c) The surface roughness on spline surfaces shall be 0.2 pm (arithmetical average) maximum. See ANSVASME B46.1, Surface
Texture.
(d) The gage handles shall conform t o ANSI 647.1, Gage Blanks.
..
NOTE:
(1 The tabulated dimensions represent direct metric conversions of the equivalent inch size splinesocket gages shown inASMElANSl
B18.3, Socket Cap, Shoulder, and Set Screws (Inch Series). Therefore,the spline socket gages shown therein are applicablet o gaging of thecorresponding size metric spline sockets.
7
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
-7
5.5499
SOCKET HEAD CAP SCREWS (METRIC SERIES)
ASMElANSl B18.3.1M-1986
portion of shank shall bewithin D maximum and the
specified minimum pitch diameter of the thread.
the depthof chamfer or rounding does not violate the
NOT GO gage penetration limit specified in para.
2.2.4.
2.2.6 Broached Sockets. For hexagon broached
sockets at or near the maximum size limit, the overcut
resulting from drilling shall not exceed 20% of the
length of any flatof the socket on nominal socketsizes
up to and
including 24 mm and 30% on larger sockets.
See Table 2, sketch (b).
2.2.7 Socket TruePosition. The axis of the socket
shall be located at true position relative to the axis of
the screw within a tolerance zone having a diameter
equal to 3% of the basic screw diameter or 0.26 mm,
whichever is greater, for nominal screw sizesup to and
including 12 mm; and equal to 6% of the basic screw
diameter for sizes larger than 12 mm - regardless of
feature size.
2.5 Threads
2.5.1 Thread Series and Form. Unless specified
otherwise, threads shall be themetric coarse series in
accordance with ANSVASME B1.13M, Metric Screw
Threads - M Profile.
2.5.2 Thread Tolerance Class. Threads shall be
tolerance class 4g6g. For plated screws, the allowance
g may be consumed by the thickness of plating so that
the maximum size limit after plating shall be that of
tolerance class 4h6h. Thread limits shall be in accordance with ANWASME B1.13M. See Appendix VI
wherein the allowance g shown for sizes up to and including 4 mm has been increased over that specified
for corresponding sizes in theIS0 documents to better
accommodate plating requirements. However,
because the minimum limits are unchanged, the screws
will be totally interchangeable.
,
2.3 Length
2.3.1 Measurement. The length of the screw shall
be measured,parallel to the axis of the screw, from the
plane of the bearing surface under thehead to the extreme end of the shank.
2.5.3 Thread Gaging. Acceptabilityof screw
threads shall bedetermined based upon System 22 of
ANWASME B1.3M.
2.3.2 ToleranceonLength.
The tolerance on
length shall be bilateral as tabulated below:
2.5.4 ThreadLength. The length of complete
thread L, shall be controlled by the grip length L, as
described in para. 2.5.4.1, and the length of total
thread L, shall be controlled by the body length LB
as set forth inpara. 2.5.4.2. The L,minimum and L,
maximum values shown in Table 6B are reference dimensions intended for calculation purposes only inaccordance with para. 2.5.4.4. See sketch Table 6B.
,J
Nominal Screw Size
Nominal Screw Length
Up to 16 mm, incl.
Over 16 mm to 50 mm, incl.
Over 50 mm to 120 mm, incl.
Over 120 mm to 200 mm, incl.
Over 200 mm
M1.6 M12
Through Through
M20
M10
Over
M20
Tolerance on Length, mm
-10.3
*0.4
-10.3
-10.4
f 1 .O
f 1.5
.. .
-,.
f.
3.
-10.7
2.5.4.1 Grip Length. The griplength L, shall be .
maximum
and represents the minimum design grip
f 1 .O
f3.0
f 2 . 5length
& 2 .of
0 the screw. It shall be measured, parallel to
the axis of screw, from the bearing surface of the head
2.3.3 Standard Lengths. The standardlengths for
to the faceof a GO thread ring gage, having the counsocket head cap screws shall be as
follows: 2.5,3,4,5,
tersink and/or counterboreremoved, which has been
6, 8, 10, 12, 16, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65,
assembled by hand as far as the thread will permit.
70,80,90,100,110,120,130,140,150,160,180,200,
The L, maximum length is a criterion for acceptance
220,240,260, and 300.
and shall conform to the values givenin Table6 or, for
diameter/lengthcombinations not showntherein,
shall be as calculated per para. 2.5.4.4.
2.4 Body
rj
-10.7
f 1.5
f 2.0
2.5.4.2 Body Length. The body length LB shall
be-minimum and represents the minimum full body
length of the screw. It shall be measured, parallel to
the axis of the screw, from thebearing surface of the
head to the top of the extrusion angle or to the last
scratch of the thread. The
LBminimum length is a criterion foracceptance and shall conformt o the values
2.4.1 Body Length. The body length (unthreaded
portion of shank) shall be asspecified in para.2.5.4.2.
2.4.2 Body Diameter. The diameter of body
throughout the bodylength shall be within the limits
for D specified in Table 1. For screws that are
threaded full length, the diameter of the unthreaded
8
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
f"---7
"
o
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
w
Ml.0
-
.-.
. .
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..
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60
90
100
110
120
130
140
150
160
160
200
220
240
260
300
,
.
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55
60
65
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3.c
8.C
13s
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20
25
30
35
40
45
Nominal
length
-
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.
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10.7
15.7
20.7
25.7
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32.C
37.c
t2.c
t7.c
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7.c
12.c
I7.C
22.c
27.C
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31.E
36.5
41 .I
Q6.E
6.t
11.5
16.E
2l.E
-
60.C
.. .
..s
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3o.c
35s
4o.c
45.c
5o.c
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78.C
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56.C
66.c
76.C
86.C
96.C
be threaded
..,
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54.0
34.0
14.0
...
. ..
24.0 26.c
29.0 3l.C
34.0 36.C
39.0 41.c
14.0 46.c
11.c
16.c
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22.0
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52.0
62.0
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82.0
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22.0
27.0
32.0
37.0
42.0
LQ
.8
full length.
.
9
.
.
. ..
.. .
,..
*..
...
51.c
51 .c
71.c
Bl .C
91.c
-
21 .c
26.C
31 .c
36.C
4l.C
6.C
1l.C
16.C
9.0
14.0
19.0
-
-LB
-
13.c
18.C
23.C
LG
M6
T
47LG
T
I
-
-
-
combinations
above heavy line shall
lengths
not tabulated,
see para. 2.5.4.4.
.
.
.
.
.
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
2.t
7.t
12s
17.t
&c
. ..
-LB
-
M5
.
.
.
.
.
168.0
.. .
.. .
.. .
.. .
98.0
108.0
118.0
128.0
148.0
48.0
58.0
88.0
78.0
88.0
18.0
23.0
28.0
33.0
38.0
See para.
.
.
.
.
.
96.7
105.7
115.7
125.7
...
45.7
55.7
65.7
75.7
65.7
15.7
20.7
25.7
30.7
35.7
.
.
.
.
.
1
2.5.4.3.
-60.5
.. .
.. .
.. .
. . .
90.5
00.5
10.5
20.5
40.5
40.5
60.5
60.5
70.5
80.5
10.5
15.5
20.5
25.5
30.5
43
64.0
94.0
04.0
.. .
.-.
94.0
04.0
14.0
24.0
44.0
44.0
54.0
64.0
74.0
64.0
24.0
29.0
34.0
LQ
Ml2
155.2
175.2
195.2
.. .
...
95.2
95.2
105.2
115.2
135.2
35.2
45.2
55.2
65.2
75.2
15.2
20.2
25.2
43
Ml4
60.0
80.0
!OO.O
!20.0
...
90.0
100.0
110.0
120.0
40.0
40.0
50.0
60.0
70.0
80.0
25.0
30.0
LQ
r r
15o.a
I7o.a
t 90.0
ti0.a
.. .
e0.a
90.0
loo.0
1io.a
I 30.a
30.0
4o.c
5o.c
60.0
70.0
15.c
20x
LB
Ml6
56.0
76.0
96.0
!I 6.0
156.0
88.0
96.0
06.0
18.0
36.0
38.0
46.0
56.0
68.0
76.0
26.0
-
-LG
T
146.0
166.0
186.0
!06.0
!46.0
76.0
86.0
96.0
106.0
128.0
26.0
36.0
48.0
66.0
66.0
16.0
LB
M20
48X
68.0
88.0
08.C
48.C
-
79.c
88.C
98.C
08.C
28.0
38-C
48.C
58.C
68.C
-
-LQ
-
r
FOR METRIC SOCKET HEAD CAP SCREWS
LBI LG
10.7
BODY AND GRIP LENGTH DIMENSIONS
T T T T T T
GENERAL
NOTES:
(a) Screws
of diameter/length
(b) For screw
sizes and/or
-
Nominal
size
TABLE 6A
35.5
55.5
75.5
95.5
135.5
65.5
75.5
85.5
95.5
15.5
25.5
35.5
45.5
55.5
69
140.0
,60.0
180.0
!OO.O
!40.0
70.0
80.0
90.0
100.0
120.0
40.0
50.0
80.0
M24
125.0
145,o
165.0
185.0
225.0
55.0
65.0
75.0
85.0
105.0
25.0
35.0
45.0
SOCKET HEAD CAP SCREW% (METRIC SERIES)
ASMElANSl 818.3.1 M-1986
I
Table 6A or, for nominal sizes larger than 24 mm,
lengths that areequal to orshorter than Lm shall be
threaded for full length. On these screws for nominal
sizes from 1.6 mm through 16 mm, the complete (full
form) threads-as determined by a GO thread ring
gage, having the countersink and/or counterbore removed, assembled by hand as far as the thread will
permit-shall extend to within 2 pitches (threads) of
the underside of head. Forsizes larger than 16 mm, the
complete threads shall extend as close to the head as
practicable.
TABLE 6BTHREAD
LENGTHS FOR
DETERMINING BODY AND GRIP
LENGTHS ON SCREWS BEYOND
DIAMETERS AND LENGTHS
TABULATED IN TABLE 6A
L,
Nominal
Size
or Basic
Screw
Diameter
.
.
L,
Thread
Length
Total Thread
Length [Note (111
Min.
Max.
M1.6
M2
M2.5
15.2
16.0
17.0
17.0
18.0
19.3
M3
M4
M5
18.0
20.0
22.0
20.5
23.5
26.0
M6
M8
M10
24.0
28.0
32.0
29.0
34.3
39.5
M l2
M14
M l6
36.0
40.0
44.0
44.8
50.0
54.0
52.0
60.0
72.0
64.5
75.0
89.5
84.0
96.0
108.0
104.0
118.5
133.0
M20
M24
M30
M36
M42
M48
-
2.5.4.4 Nontabulated Sizes and Lengths. For
screws of nominal lengths not listed in Table 6A and
for nominal sizes larger than 24 mm, the maximum
grip length L , and minimum body length LB shall be
determined from the following formulas:
LG = L - L ,
L -L n
LB =
where:
L = nominal screw length
L , = minimum thread length from Table 6B
LTT = maximum total thread length from Table 6B
Screwshavingnominallengthsfalling
between
those for whichL, and LB values are tabulated in Table 6A shall havel, and LB dimensions conforming to
those of the next shorter tabulated nominallength for
the respective screw size.
2.6 Point
The end on screws of 5 mm nominal size and larger
and of nominal lengths equivalent to 0.75 times the
basic screw diameter or longer shall be chamfered.
Thechamfer shall extend slightly below the root ofthe
thread, and the edge between the flat and chamfer
may be slightly rounded. The included angle of the
point shall be approximately 90 deg. Chamfering on
screw sizes up to and including 4 mm and of larger
sizes having lengths shorter than 0.75 times the basic
screw diameter shall be optional.
NOTE:
(1) Tabulated values are equal to LT.plus 5 times the pitch of
the coarse thread for the respectwe screw sizes.
2.7 Total Runout
The total runout between the thread, body, and
head on socket head cap screws shall be such that
screws will assembleinto a compound
hole (see Fig. 2)
that is threaded at one endto the basic thread size (tolerance class 6H minimum), for a depth equivalent to
1.5 times the basic screw diameter, and counterbored
given in Table 6A or, for diameter/length combinations not shown therein, shall be as calculated in accordance with para. 2.5.4.4.
2.5.4.3 Threaded Full Length Screws. Screws
of nominal lengths above theheavy horizontal line in
10
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
&u-?-
ASMElANSl B18.3.1M-1986
SOCKET HEAD CAP SCREWS (METRIC SERIES)
(-
’-.I
3 MATERIALS, PROCESSING, AND
MECHANICAL PROPERTIES
Socket head cap screws shall conform to the following requirements pertaining to materials, processing,
and mechanical and physical properties.
3.1 Material and Heat Treatment
FIG. 2 COMPOUND HOLEFOR CHECKING
RUNOUT BETWEEN THREAD, BODY,
AND HEAD
.
c
33
s.:
e
at the otherend to diameter A , and through thecenter
portion to diameter D,as specified in Table 7. Diameters D,and A , shall be concentric with the axis of the
thread within the equivalent of 10% of the thread
pitch diameter tolerance. The length of the center portion shall be equal to the nominal screw length minus
two times thebasic
screw diameter.Thestarting
thread
shall be chamfered,
and
the
corner
at
juncture
of diameters A , and D,shall be chamfered or rounded
to a diameter equal to B maximum as given in Table l .
2.8 Surface Roughness
For alloy steel screws of nominal sizes up to and
including 16 mm and nominal lengths equal to or less
than 8 times the basic screw diameter, the surface
roughness on the screws before plating shall not exceed 1,6 pm AA on the fillet and head bearing surfaces, nor exceed 0.8 pm AA on thethreads.
For longerlengths,larger
sizes, and corrosionresistant steel screws, the surface roughness of the
screws prior to plating shall not exceed 3.2 pm AA on
the body, fillet, and head bearing surfaces.
Normally, it shall .be sufficient to ascertain that
these surfaces on screws have the equivalent of a
smooth machined finish by visual comparison with
known surface standards.However, where it is practical and deemed necessary to measure those surfaces
with commercially available equipment, roughness
measurements shall be takenaxially on thebody and
fillet surfaces, and circumferentially on the bearing
surface.
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
3.1.1 Alloy Steel. Alloy steel metric socket head
cap screws shall conform to property class 12.9.2They
shall be fabricated fromalloy steel, and all nondimensional, mechanical, and physical properties of screws,
fabrication processes, and testing requirements shall
conform to ASTM Specification A 574M, Alloy Steel
Socket Head Cap Screws met ri^).^
3.1.2 Corrosion-ResistantSteel. Corrosionresistant steel metric socket head cap screws shall be
fabricated from a corrosion-resistant steel, and all
nondimensional, mechanical, and physical properties
of screws, fabrication processes, and testing requirements shall conform to ASTM specification F 837M,
Stainless Steel Metric Socket Head Cap Screws. Unless specifiedotherwise,thestandardcorrosionresistant steel SHCS property class shall be Al-70.
3.2 Marking Practice
All socket head cap screws of 5 mm size and larger
shall bepermanently marked to identify the property
class. In addition, screws shall be marked with the
manufacturer’s identification symbol. Markings may
be placed on the side of the head or onthe top of the
head.
3.3 Finish
The finish on alloy steel screws shall be an oiled
black oxide coating (thermal or chemical) unless
a protective plating or coating is specified by the
purchaser.
The surface finish for corrosion-resistantsteel
screws shall be passivated in accordance with ASTM
F 837M, unless specified otherwise.
%he propertyclass 12.9 designation is consistent with IS0 practices
wherein the numeral 12
symbolizes approximately1/100of the minimum tensile stress in MPa, and the decimal .9 symbolizes the approximate ratio of the minimum yield stress to the minimumtensile
stress.
’Available from American Society for Testing and Materials, 1916
Race Street, Philadelphia, Pennsylvania 19103.
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
5
14.17
14.34
14.50
14.64
14.64
25
50
70'
100
150
Length
To, lncl
50
100
150
200
250
150
300
450
600
0
25
50
70
100
Nominal
0
50
100
150
200
0
Over
i
4
20
35
60
70
100
150
300
450
.
.
.
.
.
.
.
.
.
. .
. .
. .
. .
*..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
0
20
35
60
70
5P
. *
... .
. .
. .
Ii
25
35
50
60
0
12
25
35
1.66
1.72
1.80
1.85
. . .
4
.
.
.
.
Ml.6
6
12
20
25
35
To, Incl.
Length
Size
.
.
.
.
.
.
.
.
.
.
Ml4
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4
4
.
.
.
,
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2.05
2.11
2.18
2.22
2.31
. . .
. . .
..,
. . .
21.45
21.62
21.78
21.92
21.92
.
.
.
.
.
.
.
.
.
*
.
.
.
.
.
3.21
3.27
3.35
3.40
. . .
49
FUNCTIONAL
0
6
12
20
25
Nominal
Nominal
TABLE 7
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1 ..
,
4
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Ml6
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. .
. .
*.:
. .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. .
..I
. .
. .
. .
.
.
*
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
M20
.
.
.
.
.
.
.
.
.
.
3.09
3.18
3.25
3.36
3.44
s.75
t.85
t-93
5.05
. . .
20.14
20.28
20.42
20.56
20.64
4
.
.
.
.
.
.
.
.
.
.
4
...
...
...
...
...
. . .
. . .
. . .
. . .
. . .
. . .
4
.
.
.
.
*
.
.
.
.
.
.
*
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Hole
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . .
. .
.
.
.
.
.
*
.
.
.
.
.
.
.
.
.
.
.
.
24.13
24.26
24.38
24.51
24.64
.
.
.
.
Diameters
.
.
.
.
.
4.13
4.22
4.38
4.44
4.63
. . .
. . .
‘.
. . .
. . .
. . .
43
. . .
5.74
5.83
5.90
5.01
3.09
Dd
for Shank
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5.12
5.20
5.34
5.39
5.56
.
.
.
.
.
.
.
.
36.61
36.74
36.86
36.99
37.12
.A,
.
.
.
.
for Shank
.
.
.
.
.
7.28
7.37
7.53
7.59
7.78
.
.
.
.
.
.*.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
M30
.
.
.
.
.
8.77
8.85
8.99
9.04
9.21
.
.
.
.
.
s
.
v
.
.
.
.
.
.
m
.
.
30.38
30.75
31.12
31.50
.
4
.
.
.
.
.
45.98
46.35
46.72
47.10
4
.. .
. ..
. ..
.. .
. ..
A,
36.38
36.75
37.12
37.50
...
. ..
.. .
.. .
-. .
10.18
10.41
10.51
10.66
10.79
6.13
6.26
6.36
6.51
6.64
. ..
.. .
. ..
. ..
. .*
.. .
.. *
...
...
...
A,
M6
. ..
. ..
. ..
. ..
. ..
..~
...
,..
...
...
. ..
...
.. .
. ..
. ..
.. .
.. .
.. .
.. .
. ..
4
and for Head
De and for Head
0,
M5
... ...
..., ...
... ...
.. . . . .
.. . . ..
.. . . . .
.. . .. .
.. . .. .
.. . .. .
. .. .. .
M24
M4
Di&meters
‘. . .
4
Hole
30.54
30.68
30.82
30.96
31.04
M3
4
.. .
. ..
. ..
. ..
. ..
24.48
24.64
24.79
24.95
24.96
.
.
.
.
.
.
.
.
.
.
2.60
2.70
2.78
2.90
. . .
. ..
. ..
...
. ..
.. .
a.00
6.06
4.13
4.17
q.26
.
.
.
.
.
4
M2.5
4
16.16
16.32
16.47
16.63
16.64
M2
M36
. . .
. . 1
. . .
. . .
. . .
4
55.10
55.47
55.84
56.22
8.11
8.22
8.31
8.44
8.64
...
.*.
...
...
.. .
.. .
.. .
. ..
. ..
.. .
. ..
. ..
. ..
...
...
M6
13.27
13.38
13.47
13.60
13.80
M42
10.10
10.20
10.28
10.40
10.60
.. .
...
.. .
.. .
.. .
. ..
. ..
. ..
. ..
. ..
.. .
.. .
.. .
.. .
. ..
. ..
. ..
. ..
. ..
...
42.38
42.75
43.12
43.50
.-.
. ..
. ..
. ..
.. .
.. .
...
. ..
.. .
.. .
.. .
.. .
. ..
. ..
...
.
a
. ..
...
.. .
.. .
.. .
4
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
16.30
16.40
16.48
16.60
16.80
64.22
64.59
64.96
65.34
Ml0
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
*
.
.
.
.
.
.
.
.
.
.
48.38
48.75
49.12
49.50
.. .
...
...
.. .
. ..
.
.
.
.
.
M48
12.09
12.18
12.25
12.36
12.54
.
.
.
w
.
.
.
.
.
Ml2
LIMITS FOR RUNOUT OF HEAD, BODY, AND THREAD ON METRIC SOCKET HEAD CAP SCREWS
,,,
.
.
.
.
.
.
.
1
.
.
.
.
.-.
.
.
.
.
.
.
.
.
.
.
.
.
m
.
.
.
.
73.34
73.71
74.08
74.46
.*.
.. .
.. .
.*.
.. .
4
.
.
.
.
.
.
*
.
.
.
.-
16.33
18.42
18.49
18.60
18.78
.
.
4
i
c
APPENDIX l
'4
DRILL AND COUNTERBORESIZES FOR METRIC SOCKET HEAD CAP.SCREWS
(This Appendix is not part of ASMElANSl B18.3.1M-1986, and is included here
for information purposes only.)
B
Nominal Size
or Basic
Screw Diameter
F
~~
A
Nominal Drill Size
f
X
Y
Close Fit
[Note (211
Normal Fit
[Note l3)l
Counterbore
Diameter
Countersink
Diameter
[Note (1I1
M l ,6
M2
M2.5
M3
M4
1.80
2.20
2.70
3.40
4.40
1.95
2.40
3.00
3.70
4.80
3.50
4.40
5.40
6.50
8.25
2.0
2.6
3.1
3.6
4.7
M5
M6
M8
M10
M l2
5.40
6.40
8.40
10.50
12.50
5.80
6.80
8.80
10.80
12.80
9.75
11.25
14.25
17.25
19.25
5.7
6.8
9.2
11.2
14.2
M14
M16
M 20
M24
14.50
16.50
20,50
24.50
14.75
16.75
20.75
24.75
22.25
25.50
31.50
37.50
16.2
18.2
22.4
26.4
M30
M36
M42
M48
30.75
37.00
43.00
49.00
31.75
37.50
44.00
50.00
47.50
56.50
66.00
75.00
33.4
39.4
45.6
52.6
(See notes on p. 14.)
13
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
'
NOTES:
(1) Countersink. It is considered good practice t o countersink or break the edges of holes that are
smaller than Bmaximum (see Table 1) in parts having a hardness that approaches, equals, or exceeds the screw hardness. If suchholes are not countersunk, the heads of screwsmay not seat
properly or thesharp edges on thehole may deform the fillets on
screws, thereby making them
susceptible t o fatigue in applications involving dynamicloading. The countersink or corner relief,
however, should not be largerthan isnecessary t o insure that the fillet on the
screw is cleared.
Normally, the diameter of countersink does not have t o exceed Bmaximum. Countersinks or corner reliefs in excess of thisdiameter reduce the effectivebearing areaand introduce the possibility of imbedment wherethe partst o be fastened are softer than thescrews, or of brinnelling ör
flaring the heads of the screws where the parts t o be fastened are harder than thescrews.
(2) Close Fit. The close fit isnormally limited t o holes for thoselengths of screws that
are threaded t o
the head (see Table6A) in assemblies where onlyone screw is t o be used or wheret w o or more
screws are t o be used and the matingholes are t o be produced either at assembly or bymatched
and coordinated tooling.
(3)Normal Fit. The normal fit isintended for screws of relatively long length or for assemblies involving t w o or more screws where the mating
holes aret o be produced by conventional tolerancing
methods. It provides for the maximum
allowable eccentricity of the longest standard screws and
for certainvariations in the partst o be fastened,such as: deviations in hole straightness, angularity between the
axis of the'tapped hole and that of thehole for shank, differences in center distances of the matingholes, etc.
t
14
COPYRIGHT American Society of Mechanical Engineers
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APPENDIX II
DIMENSIONS OF DRILLED HEAD METRIC HEXAGON SOCKET HEAD CAP SCREWS
(This Appendix is not partof ASMElANSl B18.3.1M-1986, and isincluded here
for informationpurposes only.)
180 deg. nom.
Six holes
Two holes
W
Nominal
Size
or Basic
Screw
Diameter
X
Drilled Hole
Diameter
Hole Center .
Location
Max.
Hole
Alignment
Check Plug
Diameter
Min.
Max.
Min.
0.95
2.00
1.50
1.35
0.80 0.8g
1.20
1.20
M6
M8
M10
2.30
2.70
1-80
2.20
1.35
1.20
M12
M16
M20
4.00 3.50 1.65
5.00 4.50 1.65
M3
M4
M5
M24
M30
M36
1.20
1.65
7.30
9.00
10.50
2.80 1.50
3.30
1.50
6.80
8.50
10.00
2.1 5
5.80
2.15
2.1 5
2.1 5
2.00
6.30
2.00
2.00
Basic
1.35
0.75
0.901.60
1.20
0.90
0.90
0.90
1.40
1.40
1.40
1.80
1.20
1.35
1.50
2.00
1.80
1.80
1.80
GENERAL NOTES:
(a) Screws. Drilled head metric hexagon socket head cap screwsnormally are not available in screw
sizes,smaller than M3 orlarger than M36. The M3 and M4 nominal screw sizes shall have t w o
drille¿ holes spaced 180 deg. apart.Nominal screw sizes M5 and larger shall have six drilled holes
spaced 60 deg. apart, unless the purchaser specifies t w o drilled holes. Drilled head screws, except for the holes, shall conform in all respects with the dimensions and requirements documented in this Standard for metric hexagon socket head cap screws.
theshall be in conformance with
(b) Holes. The drilled hole size andthe location from the top ofhead
the tabulateddimensions above. The holes shall lie within the flatsof the hexagon socket and
shall not break through thecorners of thesocket. The positioning of
holes on opposite sides of the
socket shall be such that thehole alignment check plug willpass completely through the head
without any deflection.
When specified by thepurchaser, the edge of holes on theoutside surface of the head shall be
chamfered 45 deg. t o a depth of 0.30 mm to mm.
0.50 Theedge of holes within the socket
may
contain burrs t o the extent thaf the socket willaccept a key having standard minimum width
across flats per ANSI B18.3.2M, Metric Series Hexagon Keys and Bits,
15
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
f
-.
APPENDIX 111
FORMULAS FOR DIMENSIONS
(This Appendix is not part of ASMElANSl 818.3.1 M-1986, and is included here
for information purposes only.)
Body Diameter D,1Table
Key Engagement T,1Table
- see Table 1
for values
D (min.) = D (max.) - IT13 tolerance'
D (max.)
= Basic or nominal size
T (min.) = 0.5OH (max.)
Wall Thickness G , Table 1
-4
G (min.) = 0.34H(max.)forsizes1.6mm
through 3 mm
= 0.38H(max.) for sizes 4 mm through
6 .mm
= 0.40H (max.) for sizes 8 mm through
12 mm
= 0.43H(max.) for sizes 14 mmthrough
48 mm
d)-
Functional Limits for Runout of Head, Body, and
Thread, Table 7
Head Diameter A , Table 1
A (max.) = See Table 1 for sizes 1.6 mm through
2.5 mm
- 1.5D + 1 mm for sizes 3 mm through
8 mm
- 1.5D for sizes 10 mm and larger
. A (min.) = A (rnax,) - 0.1058
d
Head Height H , Table 1
E (max.) = D (max.)
H(min,) = H(max.)
-
0.0604
Limits are based on:
D, = D + 0.0126 L + D f o r sizes up to and
including 24 mm with a maximuni of
0.64 mm
D, = D + 0.0025 L for sizes over 25 mm with a
maximum of 1.52 mm
Top of Head Chamfer or Radius S,Table 1
S (max.) = O . lOH(max.)
'Tolerances from International Standard, System of Limits and
Fits, Part 1: General, Tolerances and Deviations, I S 0 R286-1962.
Ø
.
-
16
COPYRIGHT American Society of Mechanical Engineers- .
Licensed by Information Handling Services
-
o
(This Appendix is not part ofASME/ANSI B18.3.1M-1986, and is included here
for information purposes only.)
A
H
T
G
Head
Diameter
Head
Height
Key
Engagement
Wall
Thickness
Min.
Min.
Min.
Min.
M l .6
M2
M2.5
2.86
3.62
4.32
1.46
1.86
2.36
0.70
0.55
0.55
M3
M4
M5
6.78
8.28
2.86
3.82
4.82
M6
M8
M10
9.78
12.73
15.73
5.70
7.64
9.64
M l2
M14
M16
17.73
20.67
23.67
11.57
13.57
15.57
M20
M24
M30
29.67
35.61
44.61
19.48
23.48
29.48
M36
M42
M48
53.54
62.54
71.54
35.38
41 -38
47.38
Nominal
Size
or Basic
Screw
Diameter
...
...
1.10
1.30
...
...
...
...
...
a . .
...
...
...
...
1.15
1.4
...
2.3
3.3
...
...
5.8
6.8
...
15.50
10.4
13.1
19.00
15.8
...
m . .
...
...
GENERAL NOTES:
(a) Threads. The threadtolerance class of 5g6g specified in IS0 standards is notas close as the tolerance class of 4969 specified herein.
(b) Body and Grip Length. The body and grip lengths on some sizellength combinations of screws
may notagree duet o differences in NorthAmerican thread lengthpractice. However, the thread
length on screwsspecified herein is equal t o or longer than that oncorresponding screws conforming to theI S 0 standard practice.
17
COPYRIGHT American Society of Mechanical Engineers
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APPENDIX V
--e
GOVERNMENT STANDARD ITEMS AND PART NUMBERING SYSTEM
(This Appendix is not part of ASME/ANSI B18.3.1M-1986, and is included here
for information purposes only.)
The partnumber shallconsist of the following element codes in the order shown:
(a) Document identifier - ASME/ANSI Standard
Number less decimal points
(b) Material and finish
(c) Socket type
(6) Nominal diameter
(e) Nominal length
U, Special features
NOTE: The government encourages the generaluse of this Appendix to achieve maximum parts standardization.
This Appendix establishes standard items for Government application,selected from thepossible variations of items within the scope of the Standard, and
provides a part numbering system for identification
and application in engineering documents,
The following variations are standard:
(a) Diameter/Thread Pitch and Length Combinations - as specified in Table V-1
(b) Material (Alloy Steel, Property Class 12.9, or
Corrosion-Resistant Steel, Property Class A1-70 - as
coded in Part Numbering System
(c) Finish (CadmiumPlating, Zinc Coating, or
Black Oxide Coating for Alloy Steel; Cleaning, Descaling,andPassivationforCorrosion-Resistant
Steel) - as coded in Part Numbering System
(d) Socket Type - hexagon
(e) Special Features - drilled head with each hole
chamfered on outside edge in accordance with Appendix II, or self-locking if specified
NOTE: The Part Numbering System mayalso be used for nonstandard diameter and length combinations.
QualityAssurance Provisions. Qualityassurance
provisionsshallbeinaccordancewithANSI
B18.18.1M. Inspection level B shall apply for thread
acceptability.
Packaging. Packaging shall be in accordance with
ASTM D 395 1,
18
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
c-
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
G
.
.
.
.
.
50
55
60
65
70
.
.
.
.
.
.
.
.
.
.
...
.... .
.. .
.
.
.
.
.
.
.
.
.
.
220
240
260
.
.
.
.
.
. ..
. ..
...
...
.. .
...
. . ..
...
.. .
...
130
140
150
160
180
.
.
.
.
.
.
.
.
.
.,.
..
..
..
..
. , .’
.. .
.. .
...
.. .
.
.
.
.
.
80
90
100
110
120
.
.
.
.
.
.
.
.
.
..
..
..
..
..
.
.
.
.
.
.
.
.
.
25
30
35
40
45
.
.
.
.
I
2.5 x 0.45
M3 x 0.5
M4 x 0.7
M5 x 0.8
.
..
.,.
..
..
..
.
.
.
.
.
.
.
.
..
_.
..
..
..
...
.. .
.,.
..~
...
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
., .
...
.. .
...
.r-
.
.
.
.
.
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.. .
. ..
...
. .
.. .
.
.
.
.
.
030030
..
.. .
.. .
025025
...
...
...
. .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
..
..
..
..
..
040040
...
040006
I
.
.
.
.
.
.
.
.
I
.
.
.
.
.
.
...
...
...
. ..
. ..
. ..
.. .
. ..
.. .
. ..
050050
...
...
...
...
050008
-
.
.
.
.
.
.. .
.. .
.. .
...
._.
..
..
..
.
..
...
...
._.
...
... _
060060
...
...
060010
M6 x 1
Screw
.
.
.
.
.
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
080080
...
...
...
...
.
.
.
.
.
.
.
.
.
.
.. .
. .
.. .
..~
...
.
.
.
.
.
. .
...
.-.
...
. ..
120120
.. .
. ..
.. .
.. .
.. .
100100
.. .
.. .
200200
.. .
...
...
...
240240
...
...
.
Y24 x 3
..
t-h
...
. ..
I..
..
...
1
160160
160025
x 1.7! 5 I11116x2
120020
Ikl20 x 2.
300300
130 x 3.5
USE
360300
360055
420300
420065
IU36 x 4 m 42 x 4
SIZES FOR GOVERNMENT
1
Pitch
STANDARD
and Thread
x 1.5 Ml2
100016
Standard
Diameter and
Length
Combination
080012
Ml0
Diameter
L
M8 x 1.25
Nominal
METRIC HEXAGON SOCKET HEAD CAP SCREWS -
020003
‘o2sop*LOJ000;-1
1 (
020020
016003
016016
...
IT
8
10
12
16
20
3
‘4
5
6
Nomina
TABLE V-l
480300
m48x5
i‘
1
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
-
-
-
B
C
D
EXAMPLE:
diameter,
-
A
and Finish
Code
3
8
I
GOVERNMENT
THE
ENCOURAGES
B1831AH080020D
20 mm in length
with
THE
GENERAL
Type
I
H - Hexagon
Socket
-l
USE OF THIS
Code
1 Oths
of cadmium
0
TO ACHIEVE
plated
-
L
C
alloy
Feature
r
Code
property
class
12.9,
when
8 mm in
available.
None
Drilled head with each hole
chamfered
on the outside
edge
per Appendix
II
Self-locking*
Drilled head and self-locking*
Special
0
STANDARDIZATION.
USE
will be provided
steel,
-
mm
2
PARTS
N
D
*Details
0
MAXIMUM
ITEMS FOR GOVERNMENT
of mm
8
SYSTEM
SYSTEM COVERING STANDARD
indicates
a screw,
cap; hexagon
socket
head (metric)
made
on the outside
edge.
drilled head - each hole chamfered
Alloy steel, property
class 12.9
with cadmium
plating per QQ-P416, Type II, Class 3 (5 pm
plating thickness)
Alloy steel, property
class 12.9
with zinc coating
per ASTM B
633, FeiZn5
(5 pm coating
thickness),
Type II
Alloy steel, property
class 12.9
with black oxide coating
as
specified
herein
Corrosion-resistant
steel, property class Al -70, cleaned,
descaled,
and passivated
in
accordance
with ASTM A 380
‘Material
NOTE:
PART NUMBERING
APPENDIX VI
DIMENSIONS OF METRIC THREADS FOR SMALL SIZES OF SOCKET SCREW PRODUCTS
(This Appendix is not part ofASMElANSl B18.3.1M-1986, and isincluded here
for information purposes only.)
T
I
Tolerance Class 4969 [Note (111
Nominal
Size
4gBasic
or
Thread
Diameter
Pitch
Max.
Allowance
9
[Note (311
M l .6
M2
M2.5
M3
M4
0.35
0.4
0.45
0.5
0.7
1.576
1.976
2.476
2.976
3.976
0.024
0.024
0.024
0.024
0.024
Major Diameter
69
Pitch Diameter
21
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services
Tolerance Class 4h6h [Note (211
RootPitch
Radius
0-125p
Major
6h
GO Gage
Minor
Diameter
Min.
0.04
0.05
0.06
0.06
0.08
1.600
2.000
2.500
3.090
4.000
1.373
1.740
2,208
2.675
3.545
1.221
1.567
2.013
2.459
3.242
.
."....I_.I"
................................
.
ASME BL8.3.lM
8 6 E I 0757670 0043438 T W
AMERICAN NATIONAL STANDARDS FOR BOLTS. NUTS. RIVETS. SCREWS.
WASHERS. AND SIMILAR FASTENERS
.
........................................................
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B1 8.1 1.1972 (R1 983)
Small Solid Rivets
B18.1.2-1972 (R1983)
Large Rivets
B18.1.3M-1983
Metric Small Solid Rivets
B18.2.1-1 981
Square and Hex Bolts and Screws - Inch Series
Square and Hex Nuts
B18.2.2-1972 (R19831
B18.2.3.1 M-I 979
Metric Hex Cap Screws
B18.2.3.2M-1979
Metric Formed Hex Screws
B18.2.3.3M-1979
Metric Heavy Hex Screws
B18.2.3.4M-1984
Metric Hex Flange Screws
B18.2.3.5M-1979
Metric Hex Bolts
B18.2.3.6M-1979
Metric Heavy Hex Bolts. . . . . . . . . . . . . . . . . . C
i
B1 8.2.3.7M-1979
Metric Heavy Hex Structural Bolts
B18.2.3.8M-1981
Metric Hex Lag Screws
B18.2.3.9M-1984
Metric Heavy Hex Flange Screws ................................................
B I 8.2.4.1 M-1979
Metric Hex Nuts. Style 1
B18.2.4.2M-1979
Metric Hex Nuts. Style 2
B1 8.2.4.3M-1979
Metric Slotted Hex Nuts
B18.2.4.4M-1982
Metric Hex Flange Nuts
B18.2.4.5M-1979
Metric Hex Jam Nuts .........................................................
B18.2.4.6M-1979
i
Metric Heavy Hex Nuts
818.3-1982
Socket Cap. Shoulder and Set Screws (InchSeries)
B1 8.3.1 M-1 986
Socket Head Cap Screws (Metric Series)
B18.3.2M-I979 (R1986)
Metric Series Hexagon Keys and Bits
Hexagon Socket Head Shoulder Screws (MetricSeries)
B18.3.3M-1986
B18.3.4M-1986
Hexagon Socket Button Head Cap Screws (Metric Series)
B I 8.3.5M-1986
Hexagon Socket Flat Countersunk Head Cap Screws (Metric Series)
B18.3.6M-1986
Metric Series Socket Set Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
818.5-1978
Round Head Bolts (Inch Series)
B I 8.5.2.1 M-I 981
Metric Round Head Short Square Neck Bolts
B18.5.2.2M-1982
Metric Round Head Square Neck Bolts.
B18.6.1-1981
WoodScrews
Slotted Head Cap Screws. Square Head Set Screws. and Slotted Headless
Set Screws
618.6.2-1972 (R19831
B18.6.3-1 972 (R1983)
Machine Screws and Machine Screw Nuts .......................................
B18.6.5M-1986
Metric Thread Forming and Thread Cutting Tapping Screws
Metric Machine Screws
B18.6.7M-1985
Thread Forming and Thread Cutting Tapping Screws and Metallic Drive Screws
(Inch Series)
818.6.4-1981
GeneralPurpose Semi-Tubular Rivets. Full Tubular Rivets. Split Rivets and Rivet Caps
818.7-1972 (R19801
B I 8.7.1 M-I 984
Metric General Purpose Semi-Tubular Rivets ..........................................
Clevis Pins and Cotter Pins
B18.8.1 -1 972(R1.983)
Taper Pins. Dowel Pins. Straight Pins. Grooved Pins. and Spring Pins (Inch Series)
B18.8.2-1 978
Plow Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B18.9-1958 (R19771
818.10-1982
Track Bolts and Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Miniature Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B I 8.1 1-1961 (R1983)
B18.12-1 962(R1981)
Glossary of Terms for MechanicalFasteners......................................
B18.1 3-1965 (R1983)
Screw and Washer Assemblies - Sems .........................................
618.15-1985
ForgedEyebolts
Mechanical and Performance Requirements for Prevailing-TorqueType
B18.16.1 M-1 979(R1986)
Steel Metric Hex Nuts and Hex Flange Nuts
Torque-Tension Test Requirements for Prevailing-Torque Type
B I 8.16.2M-1979 (R1986)
Steel Metric Hex Nuts and Hex Flange Nuts
Dimensional Requirements for Prevailing-Torque Type Steel Metric Hex Nuts
and Hex Flange Nuts
B18.16.3M-1982
Wing Nuts. Thumb Screws. and Wing Screws
B18.1 7, 1968 (R1983)
B18.1 8.1M-I 982
Inspection and Quality Assurance for General Purpose Metric Fasteners
Inspection and Quality Assurance for High-Volume MachineAssembly
B18.18.2M-1982
Metric Fasteners
B18.1 8.3M-1982
Inspection and Quality Assurance for Special Purpose Metric Fasteners
Inspection and Quality Assurance for Highly Specialized Engineered
B18.18.4M-1982
Applications - Metric Fasteners
818.21.1-1972 (R1983)
Lockwashers
B18.22M-1981
Metric Plain Washers
Plain Washers
818.22.1-1965 (R1981)
B18.23,l-1967 (R1975)
Beveled Washers
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M00094
COPYRIGHT American Society of Mechanical Engineers
Licensed by Information Handling Services