asme b1.10m
TRANSCRIPT
Errata to
ASME B1.10M-1997 Unified Miniature Screw Threads
On page 6, in Table 2, under the fifth column heading Height, 0.661H = 0.57259074P, the eighth and ninth entries were corrected to read O. 12883 and O. 143 15, respectively. The complete Table appears on the overleaf.
JANUARY 1998 THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
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TABL
E 2
THRE
AD
FORM
DI
MEN
SIO
NS,’
BASI
C AN
D DE
SIG
N
Pitc
h P
0.08
0 0.
090
0.10
0 0.
125
0.15
0
Heig
ht
of
ShwP
v.
H=
0.
6660
2540
P
0.08
928
0.07
794
0.08
660
0.10
825
0.12
990
Heig
ht
of
Dede
ndum
In
tern
al of
Int
ern8
1 Th
read
an
d Th
read
an
d De
pth
of
Adde
ndum
Th
read
of
Exte
rnal
Entm
mm
t Th
rwd.
6.5
64H
= 6.3
75H
= 0.4
8oO6
wOP
0324
7595
3P
0.03
840
0.02
598
0.04
320
0.02
923
0.04
600
0.03
248
0.06
000
0.04
059
0.07
200
0.04
871
Heig
ht,
Flat
at
Cres
t, Ra
dius
at
0.
661
H =
F,
= Ro
ot,
r, =
0572
5907
4P
0.12
5OOO
OOP
0.18
5181
49P
0.04
581
0.01
00
0.01
5 0.
0515
3 0.
0113
0.
017
0.05
728
0.01
25
0.01
9 0.
0715
7 0.
0156
0.
023
0.08
589
0.01
88
0.02
8
Roun
ded
Root
He
ight
, 0.5
66H
= 0.
5150
843g
P
0.04
129
0.02
57
0.00
6 0.
0464
5 0.
0289
0.
006
0.05
161
0.03
21
0.00
7 0.
0645
1 0.
0401
0.
009
0.07
741
0.04
81
0.01
1
0.17
5 0.
1515
5 0.
0840
0 0.
0568
3 0.
1002
0 0.
0219
0.
032
0.20
9 0.
1732
1 0.
0960
0 0.
0649
5 0.
1145
2 0.
0250
0.
037
0.22
5 0.
1949
6 0.
1080
0 0.
0730
7 0.
1288
3 0.
0281
0.
042
0.25
0 0.
2185
1 0.
1200
0 0.
0811
9 0.
1431
5 0.
0313
0.
046
0.30
0 0.
2598
1 0.
1440
0 0.
0974
3 0.
1717
8 0.
0375
0.
056
GENE
RAL
NOTE
: Fo
r sta
ndsrd
izatio
n,this
Ta
ble
of thr
ead
value
s ha
s be
en
estab
lishe
d ba
sed
on
a fun
ction
of
pitch
, /?
The
threa
d va
lues
base
d on
a
functi
onal
heigh
t, H,
are
us
ed
as
refer
ence
on
ly.
0.09
031
0.10
322
0.11
612
0.12
902
0.15
483
Bask
Thre
adFo
rm
Exte
rnal
Thre
ad
Desig
n Fo
rm
l- In
tern
al Th
read
De
sign
Form
Di
men
sions
. m
m
NOTE
: (1)
Fo
r inc
h co
nver
sion
of Ta
ble
2,see
Appe
ndix
6.
Flat
at
Cres
t, Ra
dius
at
F,
= Ro
ot
r, =
0.33
6743
74P
0.07
2166
78P
0.05
61
0.01
3 0.
0641
0.
014
0.07
22
0.01
6 0.
0802
0.
018
0.09
62
0.02
2
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A N A M E R I C A N N A T I O N A L S T A N D A R D
ASME B1.l OM-1 887 (Revision of ASA B1.lO-1958)
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~
STD-ASME B L - L O M - E N G L L797 I 0757b70 0583030 22b O
Date of Issuance: September 2, 1997
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 this edition.
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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 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 which provides an opportunityfor additional public input from industry, academia, regulatory agencies, and the public-at-large.
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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 assume any such liability. Users of a code or standard are expressly advised that the determination of the validity of any such patent rights, and the risk of the infringement of such rights, is entirely their own responsibility.
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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.
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Copyright Q 1997 by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
All Rights Reserved Printed in U.S.A.
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(This Foreword is not part of ASME B1.10M-1997.)
The standardization of threads for miniature fastening screws and similar purposes has been under study since 1927, when the National Screw Thread commission prepared a compilation of the practices of American manufacturers and various foreign standards. The latter included the Swiss standard NHS 56100, which first appeared in 1923. However, for want of sufficient interest, no further action was taken in the United States until 1943, when the demands of modem warfare awakened both the need for domestic standardization and the desirability of international standardization, particularly among the inch-using countries. For the consideration of this dual problem, together with other thread matters confined principally to the instrument industry, the American Standards Association established, in 1944, ASA War Committee B1.7 on Instrument Screw Threads.
The first significant progress toward standardization and unification of miniature threads was achieved at the American-British-Canadian Conference on the Unification of Engineering Standards held in Ottawa in 1945, when the delegations of these three countries joined in recommending the adoption of the NHS thread series in the size range of 0.30 mm to 0.90 mm having a 50 deg thread angle, and the development of a series closely following the NHS series for sizes larger than 0.90 mm with a 60 deg thread angle.
In June 1946 the War Committee was converted to Subcommittee No. 4 on Instrument Screw Threads of ASME Sectional Committee B1, Shortly thereafter it was learned that Swiss manufacturers were not adhering entirely to NHS 56100, but that the 60 deg thread angle made essentially in accordance with the Unified Thread Form was being widely used for the sizes below 1 mm. From this information and the results of subsequent experimental work by watch and instrument manufacturers both here and abroad, there developed a consensus favoring the 60 deg thread angle for all sizes.
At a meeting in June 1952 of Technical Committee No. 1, Screw Threads, of the International Organization for Standardization, a diameter-pitch series covering the range from 0.25 mm to 1.40 mm was adopted for recommendation to all national standardizing bodies. The Committee also agreed that further studies should be made regarding the use of the IS0 Basic Profile (or Unified Thread Form) in this range.
In the United States, where subsequent studies revealed no need, either current or anticipated, for sizes below 0.30 mm, it was established that the 60 deg angle for all sizes was feasible. It was also determined that the minor diameter of internal threads must be, and invariably is, kept above the minimum value established by the Unified Thread Form to avoid excessive tapping difficulties. From this conclusion and the calculation problems presented by the need for dimensioning this Standard in both metric and inch units, a simple plan evolved based on the coefficient of 0.52 in place of 0.54127 for basic thread height. These findings resulted in the formulation of the following recommendations by Subcommittee No. 4. for the American standard:
(a) that the series consist of all sizes from 0.30 mm to 1.400 mm in the IS0 recommendation; (b) that the 60 deg thread angle be adopted over the entire range; (c ) that the design thread forms be based on the simplified value of 0.52P, instead of
0.54127P, for the basic thread height.
... 111
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The American views were presented at both the American-British-Canadian Conference in April 1955 and the plenary session of IS0 in June 1955. The latter session developed Draft IS0 recommendation No. 84 covering a metric series from 0.25 mm to 5.00 mm, with the I S 0 Basic Thread Profile, having a 60 deg angle and a thread height of 0.54 l27P, applied over the entire range.
American sentiment was strongly in favor of the simplified coefficients for the thread sizes 1.400 mm and below, and the previous issue of this Standard was formulated to incorporate the original American recommendation on thread height. Despite this deviation, complete interchangeability with product made to I S 0 recommendation No. 84 was regarded as a certainty in view of common practice on internal threads.
Tolerances given in this Standard were entirely of national origin, as recommendations on this phase had not yet been formulated by other bodies.
A preliminary draft of this Standard, approved by Subcommittee No. 4 on June 12, 1956, was distributed to industry for comment and criticism in October 1956. This draft was then revised and submitted to the Sectional Committee B1 for letter ballot in April 1957. In response to comments received with the letter ballot, the draft was further modified at a meeting of Subcommittee No. 4 on March 6, 1958. Following the acceptance of these modifications by the Sectional Committee, the proposal was submitted to and approved by the sponsor organizations and ASA. and was formally designated as an American Standard on August 18, 1958.
This Standard remained virtually unchanged from 1958 to 1995, while the use of miniature threads diminished considerably due to electronic components, replacing many of the mechanical devices used in watches and instrumentation. There still remains, however, an active use of miniature screw threads in spacecrafts and aircrafts, as components are miniaturized for weight considerations. Attempts were made to revise the Standard between 1979 and 1983, but unresolved negative votes defeated the proposed revisions. Efforts to revise the Standard were undertaken again in 1989.
The current Standard now has a thread height of 0.554H (0.48P), which is in agreement with FED-STD-H28/5 and ISO/R1501, and which allows for interchangeability with threads produced to the previous standard ASA BI. 10-1958. The dimensions and symbology are in line with current screw thread practices. This revision of Unified Miniature Screw Threads lists all dimensions in metric units. Inch conversions of these values have been placed i n the Appendix Section of this Standard.
ASME B1.10M-1997 was approved by the American National Standards Institute on July 11. 1997.
iv
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ASME STANDARDS COMMITTEE B I Standardization and Unification of Screw Threads
(The following is the roster of the Committee at the time of approval of this Standard.)
OFFICERS
A. D. Shepherd, Jr., Chair G. L. Fechter, Secretary
COMMITTEE PERSONNEL
J. R. Anderson, Delphi Harrison Thermal System, Lockport, New York J. M. Bobelak, McDonnell Douglas Corp., St. Louis, Missouri R. M. Byrne, Trade Association Management, Inc., Tarrytown, New York D. P. Cadieux, Glastonbury Gage, Glastonbury, Connecticut F. G. Calderone, Quality Systems Implementers, Troy, Ohio L. N. Dixon, Jr., General Electric, Cincinnati, Ohio R. Dodge, Pennoyer-Dodge Co., Glendale, California A. E. Ellis, Consultant, Bedford, Massachusetts R. E. Ferry, Jr., R. B. &W, Caraopolis, Pennsylvania G. A. Flannery, Mercury Gage Co., Detroit, Michigan H. N. Frost, Defense Industrial Supply Ctr., Philadelphia, Pennsylvania D. S. George, Ford Motor Co., Dearborn. Michigan J. R. Gervasi, Kerr Lakeside, Inc., Euclid, Ohio J. Greenslade, Greenslade & Co., Fort Worth, Texas L. C. Johnson, The Johnson Gage Co., Bloomfield, Connecticut S. I. Kanter, Hanson-Whitney Co., Hartford, Connecticut R. P. Knittel, Leitech/AMTMA, Madison, Wisconsin J. A. Krippes, Pensacola, Florida R. S. Lanier, Consultant, Naples, Florida K. E. McCullough, Consultant, Willow Grove, Pennsylvania D. Miskinis, Greenfield Industries, Evans, Georgia W. R. Newman, Nylock Fastener Corp., Macomb, Michigan M. W. Rose, I T W Southern Gage Co., Erin, Tennessee G. A. Russ, Cummins Engine Co., Columbus, Indiana R. J. Sabatos, Cleveland Twist Drill Co., Asheboro, North Carolina D. M. Satava, Chagrin Falls, Ohio E. Schwartz, Consultant, Philadelphia, Pennsylvania R. H. Searr, Quantum Insp. and Testing Ltd., Burlington, Ontario, Canada R. E. Seppey, Laporte, Indiana V. B. Shook, Teledyne Landis Machine, Waynesboro, Pennsylvania A. G. Strang, Consultant, Boyds, Maryland R. D. Strong, General Motors Corp., Warren, Michigan J. F. Sullivan, National Fasteners Distr. Assoc., South Boston, Massachusetts R. L. Tennis, Caterpillar, Inc., Mossville, Illinois A. F. Thibodeau, Swanson Tool Mfg., Inc., West Hartford, Connecticut C. J. Wilson, Industrial Fasteners Inst., Cleveland, Ohio
V
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SUBCOMMITTEE 10 - MINIATURE SCREW THREADS
A. D. Shepherd, JI., Chair, Northborough, Massachusetts J. M. Bobelak, McDonnell Douglas Corp., St. Louis, Missouri F. G. Calderone, Quality Systems Implementers, Troy, Ohio A. E. Ellis, Consultant, Bedford, Massachusetts D. M. Satava, Consultant, Chagrin Falls, Ohio
vi
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CONTENTS
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standards Committee Roster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 .1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Unified Miniature Screw Thread Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Designation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Reference Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 Acceptability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Screw Thread Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Basic Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Design Profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4 Lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 Nominal Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6 Classifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7 Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8 Coated Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9 Limits of Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures 1 Basic Profile for the UNM Screw Threads ........................................ 2 Design (Maximum Material) Thread Forms ........................................ 3 Disposition of Tolerances and Crest Clearances .................................... Tables 1 Thread Form Formulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Thread Form Dimensions, Basic and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Thread Size Formulas, Basic and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Thread Size Dimensions, Basic and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Tolerance Formulas for Limits of Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Limits of Size and Tolerances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendices A Gages and Gaging for Unified Miniature Screw Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . B Inch Conversion of Table 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C Inch Conversion of Table 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D Inch Conversion of Table 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
... 111
V
2 2 2 2 2 2 2 2 3 3
3 4
I I
5 6 7 8 9
10
13 15 17 19
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ASME B1.10M-1997
UNIFIED MINIATURE SCREW THREADS
1 GENERAL ANSUASME B I .7M,* Nomenclature, Definitions, and Letter Symbols for Screw Threads
1.1 Scope Publisher: The American Society of Mechanical Engi- neers, 345 East 47th Street, New York, NY 10017 This Standard specifies the thread form, series, toler-
ance, and designation for the Unified Miniature Screw Is0 68, Is0 General Purpose Screw Threads Threads. The series covers a diameter range of 0.30 1 ~ 0 / ~ 1 5 0 1 , ISO Miniature screw Threads
mm to extending the “Profile and Publisher: International Organization for Standardiza- unified thread series that begin at 1.6 mm. tion, 3 rue de Varembe, 121 1 Geneva 20, Switzerland
1.2 Unified Miniature Screw Thread Standards
The fourteen sizes published in this Standard were endorsed by the American-British-Canadian conference of April 1955 as the basis of the unified standard among inch-using countries, and to correspond with the range of sizes in the ISO. The sizes are shown in Table 4. In interest of standardization and where design permits, selection of size should be confined to those indicated in bold type in Table 4. For more restrictive conditions, those sizes indicated in regular type in Table 4 may be used.
1.3 Designation
Unified Miniature Thread sizes of this series shall be designated on engineering drawings, in specifications, and on tools and gages (space permitting) by their nominal diameter in hundredths of a millimeter followed by the symbol “UNM” (e.g., 0.80 UNM).
On internal threads, the ful l limits of minor diameter, as given in Table 6, shall normally be considered applicable. Where this is not permissible, the designation shall be supplemented by the minor diameter limits.
1.4 Reference Documents’
The latest issues of the following documents form a part of this Standard to the extent specified herein.
1.5 Acceptability
1.5.1 Additional recommended methods for determin- ing the acceptability of miniature screw threads will be included as further experience with this thread standard is reported. Until such time, agreements must be reached between purchaser and vendor regarding the basis for determining acceptance, since practices are likely to differ considerably, particularly for external threads. Where a free choice is possible, the procedures given below, which are being used with considerable success by some producers, are suggested.
1.5.2 External Threads. The major diameter of the external thread is measured by either contact gaging, optical projection, or laser inspection equipment. All other dimensions, such as pitch diameter, lead, thread form, and minor diameter may be inspected by optical projection methods, with a magnification of lOOX rec- ommended. A suggested chart for this method is shown in Appendix A. The thread plug gages and the tap are inspected in a similar manner to externally threaded parts. Contact gaging, such as the use of “GO” and “NOT GO’ ring gages, measuring wires, and set plug gages may be used for sizes 0.70 UNM and above.
1.5.3 Internal Threads. The minor diameter of the intemal thread is gaged with “GO’ and “NOT GO’ plain cylindrical plug gages. All other elements are checked only for assemble-ability limits by means of a “GO’ thread plug gage, taking extreme care not to damage the thread. For the minimum material limits of the internal threads, the accuracy and performance
’ When the American National Standards referred to in this Standard - are superseded by a revision approved by the American National May also be obtained from American National Standards Institute. Standards Institute, the revision shall apply. I I West 42nd Street. New York, NY 10036.
1
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ASME B1.10M-1997
of the tap is relied upon. This implies that the major and pitch diameters of the tap do not exceed the maximum internal thread limits for these elements, and disregards over cutting, which is rarely incurred because of the flexibility of these small taps and the manner in which they are generally fluted.
It is recommended that the minor diameter of the internal thread be gaged with one insertion of the “NOT GO” plain cylindrical plug gage first. The “NOT GO’ plain cylindrical plug gage shall be inserted only until it meets some resistance. The minor diameter is then gaged with only one insertion of the plain cylindrical plug gage per thread, as the act of gaging can wear the thread oversize. At this point, the minor diameter is considered to be acceptable. The thread is gaged with only one insertion of the “GO’ thread plug gage. The thread is accepted or rejected on the basis of this one insertion. Repeat insertions can wear oddamage the thread.
1.5.4 Reference Temperature. The reference temperature is 20°C for the dimensions defined by this system.
1.5.5 Units of Measure. All dimensions in this Standard, including all tables, are in millimeters unless otherwise specified. Inch conversions may be found in Appendices B, C , and D.
1.5.6 Federal Government Use. When this Stan- dard is approved by the Department of Defense (DOD) and federal agencies, and is incorporated into FED-STD- H2815, Screw-Thread Standards for Federal Services, Section 5 , the use of this Standard by federal government will be subject to all requirements and limitations of FED-STD-H28/5.
2 SCREW THREAD PROFILE
2.1 Scope
The basic profile and design profiles defined in this Section are the basis of all thread dimensions given in this Standard.
2.2 Basic Profile
The basic profile for the UNM screw threads is shown in Fig. 1 (profile applies to the axial plane), and except for one element is the Unified Basic Thread Form. The exception is the height of thread engagement for which the basic value is 0.5548. The basic thread height of 0.5548 (0.48P) will not affect interchangeabil-
UNIFIED MINIATURE SCREW THREADS
ity with products made to the 1958 revision of this Standard showing 0.52P. As the resulting difference is negligible and completely offset by practical considera- tions in tapping, full internal thread heights are avoided in these small sizes to escape excessive tap breakage.
For reference, the basic profile for UNM screw threads is identical to that for IS0 metric threads in ISO/R1501.
2.3 Design Profiles
The design profiles define the maximum material conditions for the external and internal unified miniature thread as shown in Fig. 2. These forms are derived from the basic profile shown in Fig. I by the application of clearances for the crests of the addendum at the roots of the mating dedendum forms, and thereby satisfy the practical consideration that the contact between the mating pair be limited to functional surfaces of the fasteners.
2.3.1 Practically speaking, product made to the re- quirements of this Standard will be interchangeable with product made to any other standards allowing a maximum depth of engagement (or combined addendum height) of 0.5548. Internal thread heights exceeding 0.5548 should be avoided in the small thread sizes in order to avoid excessive tap breakage.
2.3.2 Formulas for the various dimensions are given in both Fig. 2 and Table 1. Values of the various dimensions for all pitches are given in Table 2.
2.4 Lead
All threads are of the single (single start) type.
2.5 Nominal Size
The thread sizes comprising this series and their respective pitches are shown in the third and second columns, respectively, of Table 4. Formulas for the dimensions are listed in Table 3. Corresponding values for all sizes are given in Table 4.
2.6 Classifications
This Standard establishes only one class of thread, with zero allowance on all diameters, in view of the manufacturing difficulties which any differentiations in tolerance would impose and because there is no demonstrated need for additional classes.
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
UNIFIED MINIATURE SCREW THREADS ASME B1.10M-1997
0.10825318P (0.125.H)
Pitch line "."_ 0.86602540P
Axis of screw thread
GENERAL NOTE: For standardization, this Table of thread values has been established based on a function of pitch, P. The thread values based on a functional height, H, are used as reference only.
FIG. 1 BASIC PROFILE FOR THE UNM SCREW THREADS
2.7 Tolerance
2.7.1 All tolerance governing limits of size are based on functions of the pitch only and apply to lengths of engagement from v3 to 1 v2 times the nominal diameter. Lengths of engagement and nominal diameter are not incorporated in any of the tolerance formulas in view of the following.
(u) In the small thread sizes covered by this Standard, lengths of engagement significantly below or above the range covered by the formulas are not frequently employed.
(b ) Functional fitness in these small sizes is depen- dent principally upon the properties of the thread rather than the size of the threaded number.
(c) Total tolerance is too small to permit the imposi- tion of minor modifications.
2.7.2 On external threads, tolerance is applied to the design sizes in the minus direction. On internal threads, tolerance is applied to the design size in the plus direction. Tolerance formulas are given in Table 5. Their values are given in Table 6.
2.8 Coated Threads
It is not within the scope of this Standard to make recommendations for thickness of, or specify limits for, coatings.
2.9 Limits of Size
The limits of size resulting from the application of the specified tolerance are illustrated in Fig. 3. Their values are given in Table 6.
3
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
ASME B1.10M-1997 UNIFIED MINIATURE SCREW THREADS
Basis for minimum major 0.07216878P diameter specified in
90 deg 4 Axis of internal thread
"" ---
A I \
"I-
I 'Junction of root Basis for maximum minor contour and flank diameter specified in
90 deg Tables
/ --..- Axis of external thread
GENERAL NOTE: For standardization, this Table of thread values has been established based on a function of pitch, f . The thread values based on a functional height, H, are used as reference only.
FIG. 2 DESIGN (MAXIMUM MATERIAL) THREAD FORMS
4
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UNIFIED MINIATURE SCREW THREADS ASME B1.10M-1997
TABLE 1 THREAD FORM FORMULAS
Element Symbol Formula
BASIC THREAD FORM
Angle of thread 2oL Half angle of thread Pitch of thread P Height of sharp V thread H Addendum of basic thread Height of basic thread
oL
hab hb
DESIGN FORM - EXTERNAL THREAD
Addendum has Height h, Flat at crest F C S
Radius at root r,
DESIGN FORM - INTERNAL THREAD
Height of engagement Height of thread Flat at crest Radius at root
he hn Fcn r ,
60 deg 30 deg
0.86602540P 0.32475953P (0.375H) 0.48000000P (0.554M
0.32475953P (0.375H) 0.57259074P (0.661 H) O. 12500000 P 0.18518149P
0.48000000P (0.554M 0.48000000P (0.554M 0.32074374P 0.07216878P ...
GENERAL NOTE: For standardization, this Table of thread values has been established based on a function of pitch, P. The thread values based on a functional height, H, are used as reference only.
5
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
TABL
E 2
THR
EAD
FO
RM
D
IMEN
SIO
NS,
’ BA
SIC
AN
D
DES
IGN
Pitch
P
Heigh
t of
Shar
p V,
H=
0.8
6602
54OP
Heigh
t of
Inter
nal
Thre
ad
and
Depth
of
Thre
ad
Enga
geme
nt,
0.554
H =
0.46
0000
00P
Dede
ndum
of
Inter
nal
Thre
ad
and
Adde
ndum
of
Exter
nal
Thre
ad,
0.375
H =
0.32
4759
53P
Heigh
t, 0.
661
H =
0.57
2590
74P
Flat
at Cr
est,
Fcs
= 0.1
25OO
OOOP
Radiu
s at
Root,
rrs
=
0.18
5181
49P
Roun
ded
Root
Heigh
t, 0.5
96H
= 0.
5160
8439
P
Flat
at Cr
est,
Fen
= 0.
3207
4374
P
m 0.
080
0.06
928
0.03
840
0.02
598
0.04
581
0.01
00
0.09
0 0.
0779
4 0.
0432
0 0.
0292
3 0.
0515
3 0.
0113
0.
100
0.08
660
0.04
800
0.03
248
0.05
726
0.01
25
0.12
5 0.
1082
5 0.
0600
0 0.
0405
9 0.
0715
7 0.
0156
0.
150
0.12
990
0.07
200
0.04
871
0.08
589
0.01
88
0.01
5 0.
017
0.01
9 /
0.02
3 0.
028
0.04
129
0.02
57
0.00
6 0.
0464
5 0.
0289
0.
006
0.05
161
0.03
2 1
0.00
7 0.
0645
1 0.
0401
0.
009
0.07
741
0.04
81
0.01
1
0.17
5 0.
1515
5 0.
0840
0 0.
0568
3 0.
1002
0 0.
0219
0.
032
0.09
031
0.05
61
0.20
0 0.
1732
1 0.
0960
0 0.
0649
5 0.
1145
2 0.
0250
0.
037
0.10
322
0.06
41
0.22
5 0.
1948
6 0.
1080
0 0.
0730
7 0.
1286
3 0.
0281
0.
042
0.11
612
0.07
22
0.25
0 0.
2165
1 0.
1200
0 0.
0811
9 0.
1431
6 0.
0313
0.
046
0.12
902
0.08
02
0.30
0 0.
2598
1 0.
1440
0 0.
0974
3 0.
1717
8 0.
0375
0.
056
0.15
483
0.09
62
Basic
Th
read
Fo
rm
r Di
mens
ions,
mm
Exter
nal
Thre
ad
Desig
n Fo
rm
r
GENE
RAL
NOTE
: Fo
r sta
ndar
dizati
on,th
is Ta
ble
of thr
ead
value
s ha
s be
en
estab
lishe
d ba
sed
on
a fun
ction
of
pitch
, I?
The
threa
d va
lues
base
d on
a
functi
onal
heigh
t, /i,
are
used
as
re
feren
ce
only.
NOTE
: (I)
For
inch
conv
ersio
n of
Table
2,
see
Appe
ndix
B.
Radiu
s at
Root,
r,,
= 0.
0721
6878
P
Inter
nal
Thre
ad
Desig
n Fo
rm
0.01
3 0.
014
0.01
6 0.
018
0.02
2 2 -n m 0
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
UNIFIED MINIATURE SCREW THREADS ASME B1.10M-1997
TABLE 3 THREAD SIZE FORMULAS, BASIC AND DESIGN
Dimension Symbol Formula [Note (111
Major diameter, nominal and basic D, d (BSC) Major diameter of external thread d D, d (BSC) Major diameter of internal thread D D, d (BSC)
. . .
Pitch diameter, basic 44 (BSC) D,d (BSC)-Zh,b =
Pitch diameter of external thread 4 44 (BSC)
Pitch diameter of internal thread 4 44 (BSC)
D,d (BSC)-0.64951905P
[Note (2)l
Minor diameter, basic Old1 (BSC) D,d (BSC)-Zhb =
Minor diameter of external thread 4 D,d (BSC)-2hs =
Minor diameter of internal thread 4 014 (BSC)
NOTES: (1) Metric units (millimeters) apply in all formulas. (2) Only one class of thread, with no allowance on the pitch diameter, is provided.
D,d (BSC)-O.96P
D,d (BSC)-l.l4518P
7
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
TABL
E 4
THR
EAD
SI
ZE D
IMEN
SIO
NS,
’ BA
SIC
AN
D
DES
IGN
Size
De
signa
tion
Pitch
, P
Basic
Ma
jor
Basic
Pi
tch
Mino
r Di
amete
r Di
amete
r, Di
amete
r, Ex
terna
l Th
read
s, W
4X4
d,-l.
l4518
P=
4
Mino
r Di
amete
r Int
erna
l Th
read
s, D,
-0.96
P
Nomi
nal
Major
Di
amete
r Int
erna
l Th
read
s, D
mm
mm
mm
mm
mm
0.30
UNM
0.08
0 0.
300
0.24
8 0.
208
0.22
3 0.
300
0.35
UNM
0.09
0 0.
350
0.29
2 0.
247
0.26
4 0.
350
0.40
m 0.4
5 0.5
0 0.5
5
UNM
0.10
0 0.
400
0.33
5 0.
285
0.30
4 0.
400
UNM
0.10
0 0.
450
0.38
5 0.
335
0.35
4 0.
450
UNM
0.12
5 0.
500
0.41
9 0.
357
0.38
0 0.
500
UNM
0.12
5 0.
550
0.46
9 0.
407
0.43
0 0.
550
0.60
UNM
0.15
0 0.
600
0.50
3 0.
428
0.45
6 0.
600
0.70
UNM
0.17
5 0.
700
0.58
6 0.
500
0.53
2 0.
700
0.80
UNM
0.20
0 0.
800
0.67
0 0.
571
0.60
8 0.
800
0.90
UNM
0.22
5 0.
900
0.75
4 0.
642
0.68
4 0.
900
1.00
UNM
0.25
0 1 .
ooo
0.83
8 0.
714
0.76
0 1.
000
1.10
UNM
0.25
0 1.
100
0.93
8 0.
814
0.86
0 1.
100
1.20
UNM
0.25
0 1.
200
1.03
8 6.
914
0.96
0 1.
200
1.40
UNM
0.30
0 1.
400
1.20
5 1.
056
1.11
2 1.
400
Lead
An
gle
at Se
ction
al Ar
ea
Basic
Pi
tch
at Mi
nor
Diam
eter,
Diam
eter
4, h
D-1.1
44P
deg
min
5 52
5
37
5 26
4
44
5 26
4
51
5 26
5
26
5 26
5
26
5 26
4
51
4 23
4
32
sq
mm
0.03
398
0.04
792
0.06
379
0.08
814
0.10
010
0.13
010
0.14
387
0.19
635
0.25
607
0.32
371
0.40
039
0.52
040
C z 0.
6561
2 5
0.87
583
ii 0
GENE
RAL
NOTE
: Si
zes
show
n in
bold
type
are
prefe
rred.
It is
reco
mmen
ded
that
selec
tion
be
confi
ned
to the
se
sizes
ins
ofar
as
poss
ible.
-NOT
E:
(1)
For
inch
conv
ersio
n of
Table
4,
See
Appe
ndix
C.
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
UNIFIED MINIATURE SCREW THREADS
TABLE 5 TOLERANCE FORMULAS FOR LIMITS OF SIZE
Dimension Formula ~ ~~
External thread, major diameter 0.12P + 0.006 External thread, pitch diameter 0.08P + 0.008 External thread, minor diameter
[Note (111 O. 16P + 0.008
Internal thread, major diameter
Internal thread, pitch diameter 0.08P + 0.008 Internal thread, minor diameter 0.32P + 0.012
[Note (111 0.168P + 0.008
ASME Bl.lOM-1997
NOTE: (1) Tolerance is used in the design of tools.
9
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
W
i P G 5
TABL
E 6
LIM
ITS
OF
SIZE
AN
D
TOLE
RAN
CES
r Ex
terna
l Th
read
s
Pitch
Di
amete
r
Inter
nal
Thre
ads
Mino
r Di
amete
r r
Pitch
Di
amete
r r Ma
jor
Diam
eter
t I-
r Mino
r Di
amete
r
Min.
, Ma
x. (1)
. mm
0.30
0 0.
321
0.35
0 0.
373
0.40
0 0.
425
0.45
0 0.
475
0.50
0 0.
529
0.55
0 0.
579
0.60
0 0.
633
0.70
0 0.
737
0.80
0 0.
842
0.90
0 0.
946
1 .oo
o 1.
100
1.20
0 1.
400
1.05
0 1.
150
1.25
0 1.
458
5 5 iF 0
Major
Di
amete
r
Size
De
signa
tion
Min.
, mm
To
l., mm
Mi
n.,
mm
Min.
, mm
0.30
UNM
0.35
UNM
0.40
UNM
0.45
UNM
0.50
UNM
s 0.5
5 UN
M
0.60
UNM
0.70
UNM
0.80
UNM
0.90
UNM
1 .OO
UNM
1.1
0 UN
M 1.2
0 UN
M 1.4
0 UN
M
0.28
4 0.
333
0.01
4 0.
015
0.22
3 0.
264
0.24
8 0.
292
0.38
2 0.
432
0.47
9 0.
529
0.01
6 0.
016
0.01
8 0.
018
0.30
4 0.
354
0.38
0 0.
430
0.33
5 0.
385
0.41
9 0.
469
Pitch
, Ma
x.,
Tol.,
Max.,
Mi
n.,
Max.,
Mi
n.
II),
Max.,
To
l., mm
mm
mm
mm
mm
mm
mm
mm
mm
0.08
0 0.
300
0.01
6 0.
248
0.23
4 0.
208
0.18
7 0.
266
0.03
7 0.
090
0.35
0 0.
017
0.29
2 0.
277
0.24
7 0.
225
0.30
5 0.
041
0.10
0 0.
400
0.01
8 0.
335
0.31
9 0.
285
0.26
1 0.
348
0.04
4 0.
100
0.45
0 0.
018
0.38
5 0.
369
0.33
5 0.
311
0.39
8 0.
044
0.12
5 0.
500
0.02
1 0.
419
0.40
1 0.
357
0.32
9 0.
432
0.05
2 0.
125
0.55
0 0.
021
0.46
9 0.
451
0.40
7 0.
379
0.48
2 0.
052
0.15
0 0.
600
0.02
4 0.
503
0.48
3 0.
428
0.39
6 0.
516
0.06
0 0.
175
0.70
0 0.
027
0.58
6 0.
564
0.50
0 0.
464
0.60
0 0.
068
0.20
0 0.
800
0.03
0 0.
670
0.64
6 0.
571
0.53
1 0.
684
0.07
6 0.
225
0.90
0 0.
033
0.75
4 0.
728
0.64
2 0.
598
0.76
8 0.
084
0.25
0 1.
000
0.03
6 0.
838
0.81
0 0.
714
0.66
6 0.
852
0.09
2 0.
250
1.10
0 0.
036
0.93
8 0.
910
0.81
4 0.
766
0.95
2 0.
092
0.25
0 1.
200
0.03
6 1.
038
1.01
0 0.
914
0.86
6 1.
052
0.09
2 0.
300
1.40
0 0.
042
1.20
5 1.
173
I .05
6 1 .
ooo
1.22
0 0.
108
GENE
RAL
NOTE
S:
(a)
For
inch
conv
ersio
n of
Table
6,
see
Appe
ndix
D.
(b)
Size
s sh
own
in bo
ld typ
e ar
e pr
eferre
d. It
is re
comm
ende
d tha
t se
lectio
n be
co
nfine
d to
these
siz
es
insofa
r as
po
ssibl
e.
0.57
6 0.
673
0.77
0 0.
867
0.02
0 0.
022
0.02
4 0.
026
0.45
6 0.
532
0.60
8 0.
684
0.50
3 0.
586
0.67
0 0.
754
0.96
4 1.
064
1.16
4 1.
358
0.02
8 0.
028
0.02
8 0.
032
0.76
0 0.
860
0.96
0 1.
112
0.83
8 0.
938
1.03
8 1.
205
NOTE
: (1)
Di
mens
ion
is us
ed
in the
de
sign
of too
ls.
Gene
rally
, dia
meter
ac
cepta
nce
is ba
sed
upon
ma
ximum
ma
teria
l co
nditio
n ga
ging,
Max.,
mm
To
l., mm
0.26
2 0.
307
0.01
4 0.
015
0.35
1 0.
016
0.40
1 0.
016
0.43
7 0.
018
0.48
7 0.
018
0.52
3 0.
020
0.60
8 0.
022
0.69
4 0.
024
0.78
0 0.
026
0.86
6 0.
028
0.96
6 0.
028
1.06
6 0.
028
1.23
7 0.
032
I 0 -d
ln -0
o-
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
UNIFIED MINIATURE SCREW THREADS ASME B1.10M-1997
'I2 tolerance on major diameter r of external thread
L
c al al
.- 5 U
.- ô E m
u v] .- m
U m
5
E
L
- m al
al
O
al al
c
L
L
c
.- 5
i 5
I
U O L
.-
E .- X
U
r, 2
E - m al X al
O
al al
c
L
L
c
5
E 5
.- U
.- ô
._ E
r c .-
External Thread [Screw)
' /2 minor diameter tolerance on external thread
U m
r, ?
E - m al X al
O
al
Y
c
L
c
E m U
O c
.- L
.- E
E 6
r" .- Y
U , m ? 5 - m al C
E c .- c O L
CI al al
.- E, U L
O C .- E E .- X
2
FIG. 3 DISPOSITION OF TOLERANCES AND CREST CLEARANCES
I I
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
APPENDIX A GAGES AND GAGING FOR UNIFIED MINIATURE SCREW THREADS
(This Appendix is not part of ASME B1.10M-1997 and is included for information only.)
The establishment of specifications for gages for Unified Miniature Screw Threads is not within the scope of this document. However, in the absence of a gage standard, the development of which is awaiting the accumulation of more experience with this thread standard, there is presented below, i n Fig. A l , an illustration of a chart which has been found very satisfactory for the optical projection method of inspec- tion of external threads. Inspection at a magnification of lOOX is recommended and at this scale the charts should be accurate to within +0.01 in. on all diameters and on pitches cumulatively up to five pitches.
13
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Maximum envelope Limits
Minimum major
Minimum Pitch - - Minimum minor
0.80 UNM External Thread
1 oox
Minor diameter
Pitch diameter
Major diameter . I Set-up
FIG. A l EXAMPLE OF PROJECTION COMPARATOR CHART FOR EXTERNAL THREAD
14
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
APPENDIX B INCH CONVERSION OF TABLE 2
(This Appendix is not part of ASME Bl.lOM-1997 and is included for information only.)
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
TABL
E B
l TH
REA
D
FOR
M
DIM
ENSI
ON
S,
BASI
C
AND
D
ESIG
N
Thre
ads
Per
Inch, n
z 31
7 '/2
0.
0031
50
0.00
2728
0.
0015
12
0.00
1023
0.
0018
04
0.00
039
2827
9 0.
0035
43
0.00
3069
0.
0017
01
0.00
1151
0.
0020
29
0.00
044
254
0.00
3937
0.
0034
09
0.00
1890
0.
0012
78
0.00
2254
0.
0004
9 20
3 ?I
0.00
492
1 0.
0042
62
0.00
2362
0.
0015
98
0.00
2818
0.
0006
1 16
9 5;
0.00
5906
0.
0051
14
0.00
2835
0.
0019
18
0.00
3381
0.
0007
4
0.00
06
0.00
1626
0.
0010
1 0.
0002
0.
0007
0.
0018
29
0.00
114
0.00
02
0.00
07
0.00
2032
0.
0012
6 0.
0003
0.
0009
0.
0025
40
0.00
158
0.00
04
0.00
11
0.00
3048
0.
0018
9 0.
0004
145
7, 0.
0068
90
0.00
5967
0.
0033
07
0.00
2237
0.
0039
45
0.00
086
0.00
13
0.00
3556
0.
0022
1 0.
0005
12
7 0.
0078
74
0.00
6819
0.
0037
80
0.00
2557
0.
0045
09
0.00
098
0.00
15
0.00
4064
0.
0025
2 0.
0006
11
28/,
0.00
8858
0.
0076
72
0.00
4252
0.
0028
77
0.00
5072
0.
0011
1 0.
0017
0.
0045
72
0.00
284
0.00
06
101
"/5
0.00
9843
0.
0085
24
0.00
4724
0.
0031
96
0.00
5636
0.
0012
3 0.
0018
0.
0050
80
0.00
316
0.00
07
84
T3
0.01
1811
0.
0102
29
0.00
5669
0.
0038
36
0.00
6763
0.
0014
8 0.
0022
0.
0060
96
0.00
379
0.00
09
Pitch
, P
Basic
Th
read
Fo
rm
Heigh
t of
Shar
p V,
H=
0.8
6602
54OP
Heigh
t of
inter
nal
Thre
ad
and
Depth
of
Thre
ad
Enga
geme
nt,
0.554
H =
0.48O
OOOO
OP
-r
Dede
ndum
of
Inter
nal
Thre
ad
and
Adde
ndum
of
Exter
nal
Thre
ad,
0.37
5 H
= 0.
3247
5953
P
Exter
n
Heigh
t, 0.6
61H
= 0.
5725
9074
P
Thre
ad
Desic
Fo
rm
Flat
at Cr
est,
Fcs
= 0.
1250
0000
P
Radiu
s at
Root,
rrs
=
0.18
5181
49P
Inter
n
Boun
ded
Root
Heigh
t, 0.
596
H =
0.51
8084
39P
GENE
RAL
NOTE
: Fo
r sta
ndar
dizati
on,
this
Table
of
threa
d va
lues
has
been
es
tablis
hed
base
d on
a
functi
on
of pit
ch,
P. T
he
threa
d va
lues
base
d on
a
functi
onal
heigh
t, H,
ar
e us
ed
as
refer
ence
on
ly.
Thre
ad
Desig
Fo
rm
Flat
at Ra
dius
at Cr
est,
Root,
Fe
n =
r m =
0.
3207
4374
P 0.
0721
6878
P
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
APPENDIX C INCH CONVERSION OF TABLE 4
(This Appendix is not part of ASME B1.10M-I997 and is included for information only.)
17
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
VI
-I W . z
Size
De
signa
tion
Nomi
nal
Major
Di
amete
r Int
erna
l Th
read
s, D
in.
0.30
UNM
0.35
UNM
0.01
18
0.01
38
z 0.4
0 UN
M 0.4
5 UN
M 0.5
0 UN
M 0.5
5 UN
M
Mino
r Di
amete
r Ba
sic
Major
Ba
sic
Pitch
Mi
nor
Diam
eter
Inter
nal
Diam
eter,
0, Di
amete
r, Ex
terna
l Th
read
s, Th
read
s, d
Thre
ads
4.4
d,-1.1
4518
k 4
D,-0
.96P
Per
Inch,
n in.
in.
in.
in.
318
0.01
18
0.06
68
0.00
82
0.00
88
282
0.01
38
0.01
15
0.00
97
0.01
04
254
0.01
57
0.01
32
0.01
12
0.01
20
254
0.01
77
0.01
52
0.01
32
0.01
39
203
0.01
97
0.01
65
0.01
41
0.01
50
203
0.02
17
0.01
85
0.01
60
0.01
69
169
0.02
36
0.01
98
0.01
69
0.01
80
145
0.02
76
0.02
31
0.01
97
0.02
09
127
0.03
15
0.02
64
0.02
25
0.02
39
*13
0.03
54
0.02
97
0.02
53
0.02
69
102
0.03
94
0.03
30
0.02
81
0.02
99
102
0.04
33
0.03
69
0.03
20
0.03
39
102
0.04
72
0.04
09
0.03
60
0.03
78
85
0.05
51
0.04
74
0.04
16
0.04
38
GENE
RAL
NOTE
: Si
zes
show
n in
bold
type
are
prefe
rred.
It is
reco
mmen
ded
that
selec
tion
be
confi
ned
to the
se
sizes
ins
ofar
as
poss
ible.
0.01
57
0.01
77
0.01
97
0.02
17
0.60
UNM
0.70
UNM
0.80
UNM
0.90
UNM
0.02
36
0.02
76
0.03
15
0.03
54
1 .oo
UN
M 1.1
0 UN
M 1.2
0 UN
M 1.4
0 UN
M
0.03
94
0.04
33
0.04
72
0.05
51
TABL
E C
l TH
REA
D
SIZE
D
IMEN
SIO
NS,
BA
SIC
AN
D
DES
IGN
Lead
An
gle
at Ba
sic
Pitch
Di
amete
r, A
deg
min
5 52
5
37
5 26
4
44
5 26
4
51
5 28
5
26
5 26
5
26
5 26
4
51
4 23
4
32
Secti
onal
Area
at
Mino
r Di
amete
r 4,
D-1.1
4518
P
sq
in.
5.27
x 1O
-5 7.4
3
9.88
1.37
x 10
-4
1.55
2.02
2.23
3.04
3.97
5.02
6.21
8.07
1.02
x 10
-3
1.36
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
APPENDIX D INCH CONVERSION OF TABLE 6
(This Appendix is not part of 6l.lOM-1997 and is included for information only.)
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services
TABL
E D
l LI
M-IT
S O
F SI
ZE A
ND
TO
LER
ANC
ES
f
Exter
nal
Thre
ads
Pitch
Di
amete
r
Inter
nal
Thre
ads
Mino
r Di
amete
r T
Pitch
Di
amete
r T
Major
Di
amete
r T
Major
Di
amete
r Mi
nor
Diam
eter
Size
De
signa
tion
Thre
ads
Per
Inch
Max.,
Mi
n.,
Tol.,
Max.,
Mi
n.,
Tol.,
Max.,
Mi
n.
(I),
Min.
, Ma
x.,
Tol.,
Min.
, Ma
x.,
Tol.,
in.
in.
in.
in.
in.
in.
in.
in.
in.
in.
in.
in.
in.
in.
L Min.
, in.
Ma
x. (1
1, in.
0.30
UNM
0.35
UNM
318
0.01
18
0.01
12
0.00
06
0.00
98
0.00
92
0.00
06
0.00
62
0.00
74
0.00
88
0.01
02
0.00
14
282
0.01
38
0.01
31
0.00
07
0.01
15
0.01
09
0.00
06
0.00
97
0.00
89
0.01
04
0.01
20
0.00
16
0.00
98
0.01
04
0.00
06
0.01
18
0.01
26
0.01
15
0.01
21
0.00
06
0.01
38
0.01
47
0.40
UNM
254
0.01
57
0.01
50
0.00
07
0.01
32
0.01
26
0.00
06
0.01
12
0.01
03
0.01
24
0.01
37
0.00
17
0.01
32
0.01
38
0.00
06
0.01
57
0.01
67
0.45
UNM
254
0.01
77
0.01
70
0.00
07
0.01
52
0.01
45
0.00
07
0.01
32
0.01
22
0.01
39
0.01
57
0.00
18
0.01
52
0.01
58
0.00
06
0.01
77
0.01
87
0.50
UNM
203
0.01
97
0.01
89
0.00
08
0.01
65
0.01
58
0.06
67
0.01
41
0.01
30
0.01
50
0.01
70
0.00
20
0.01
65
0.01
72
0.00
07
0.01
97
0.02
08
g 0.5
5 UN
M 20
3 0.
0217
0.
0208
0.
0009
0.
0185
0.
0177
0.
0008
0.
0160
0.
0149
0.
0169
0.
0190
0.
0021
0.
0185
0.
0192
0.
0007
0.
0217
0.
0228
0.60
UNM
169
0.02
36
0.02
27
0.00
09
0.01
98
0.01
90
0.00
08
0.01
69
0.01
56
0.01
80
0.02
03
0.00
23
0.01
98
0.02
06
0.00
08
0.02
36
0.02
49
0.70
UNM
145
0.02
76
0.02
65
0.00
11
0.02
31
0.02
22
0.00
09
0.01
97
0.01
83
0.02
09
0.02
36
0.00
27
0.02
31
0.02
40
0.00
09
0.02
76
0.02
90
0.80
UNM
127
0.03
15
0.03
03
0.00
12
0.02
64
0.02
54
0.00
10
0.02
25
0.02
09
0.02
39
0.02
89
0.00
30
0.02
64
0.02
73
0.00
09
0.03
15
0.03
31
0.90
UNM
113
0.03
54
0.03
41
0.00
13
0.02
97
0.02
87
0.00
10
0.02
58
0.02
35
0.02
69
0.03
02
0.00
33
0.02
97
0.03
07
0.00
10
0.03
54
0.03
72
1.00
UNM
102
0.03
64
0.03
80
0.00
14
0.03
30
0.03
19
0.00
11
0.02
81
0.02
62
0.02
99
0.03
35
0.06
36
0.03
30
0.03
41
0.00
11
0.03
94
0.04
13
1.10
UNM
102
0.04
33
0.04
19
0.00
14
0.03
67
0.03
58
0.00
11
0.03
20
0.03
02
0.03
39
0.03
75
0.00
36
0.03
67
0.03
80
0.00
11
0.04
33
0.04
53
1.20
UNM
102
0.04
72
0.04
58
0.00
14
0.04
09
0.03
97
0.00
12
0.03
60
0.03
41
0.03
78
0.04
14
0.00
36
0.04
09
0.04
26
0.00
11
0.04
72
0.04
92
1.40
UNM
85
0.05
51
0.05
35
0.00
16
0.04
74
0.04
62
0.00
12
0.04
16
0.03
94
0.04
38
0.04
80
0.00
42
0.04
74
0.04
87
0.00
13
0.05
51
0.05
74
GENE
RAL
NOTE
: Si
zes
show
n in
bold
type
are
prefe
rred.
It is
reco
mmen
ded
that
selec
tion
be
confi
ned
to the
se
sizes
ins
ofar
as
poss
ible.
NOTE
: (1)
Di
mens
ion
is us
ed
in the
de
sign
of too
ls.
Gene
rally
dia
meter
ac
cepta
nce
is ba
sed
upon
ma
ximum
ma
teria
l co
nditio
n ga
ging.
COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services