1、ANSI-B1.20.1 ADOPTION NOTICE ANSI-B1.20.1, “Pipe Threads, General Purpose (Inch) , “ was adopted on October 3, 1994 for use by the Department of Defense (DoD). Proposed changes by DoD activities must be submitted to the DoD Adopting Activity: Commanding Officer, Naval Construction Battalion Center,
2、Code 156, 1000 23rd Avenue, Port Hueneme, CA 93043-4301. DoD activities may obtain copies of this standard from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094. The private sector and other Government agencies may purchase copies from the America
3、n National Standards Institute, 11 West 42nd Street, New York, NY 10036. Custodians: Army - ME Navy - YD-1 DLA - CS Adopting Activity Navy - YD-1 AREA THDS DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Copyright ASME International Provided by IHS under license wit
4、h ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-AN AMERICAN NATIONAL STANDARD PIPE THREADS, GENERAL PURPOSE (INCH) ANSI/ASME B1.20.1 - 1983 (REVISION AND REDESIGNATION OF ANSI 82.14968) SPONSORED AND PUBLISHED BY THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS Uni
5、ted Engineering Center 345 East 47th Street New York, N. Y. 1 O01 7 -_ Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-Date of Issuance: August 31,1983 This code or standard was developed under proce
6、dures 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
7、 for public review and comment which provides an opportunity for additional public input from industry, academia, regulatory agen- cies, 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
8、 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
9、 are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is entirely their own responsibility. Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted as government or in
10、dustry endorsement of this code or standard. 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. Copyright 1983 by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS All Rights Reserved Printed in U.
11、S.A. Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-FOREWORD (This Foreword is not part of American National Standard, Pipe Threads, General Purpose (Inch) ANSIIASME B1.20.1“l983. In 1973 American N
12、ational Standards Committee B2, which had.formerly been responsible for pipe thread standards, was absorbed by ANSI Standards Committee B1 and reorganized as subcommittee 20. A com- plete rewrite of the B2.2-1968 standard on Dryseal Pipe Threads has been completed, with the product thread data in se
13、parate documents from the gaging standards for Dryseal Pipe Threads. The system of num- bering, to include metric conversions, is as follows: ANSI B1.20.3-1976 Dryseal Pipe Threads (Inch) ANSI B1.20.4-1976 Dryseal Pipe Threads (Metric Translation) ANSI B1.20.5-1978 Gaging for Dryseal Pipe Threads (I
14、nch) In preparation, B1.2O.6M Gaging for Dryseal Pipe Threads (Metric Translation) A complete rewrite of the B2.1-1968 standard on Pipe Threads (Except Dryseal) was then undertaken. The system of numbering, to include metric conversions, is as follows: ANSIlASME B1.20.1 Pipe Threads, General Purpose
15、 (Inch) In preparation, B1.20.2MPipe Threads, General Purpose (Metric Translation) These standards, ANSI/ASME B1.20.1 and B1.20.2M, have product thread dimensions and gaging in the same document. Thread inspection specifies the use of L, taper thread plug and ring gages similar to B2.1-1968. In addi
16、tion, emphasis is given to the requirement that all basic thread design dimensions are to be met within the specified tolerances. The data in this Standard supersede those given in ANSI B2.1-1968. . The ANSIlASME B1.20.1 was approved by ASME Standards Committee B1 on Decembel 1, 1982 for publication
17、 as an official ANSI standard. The proposed standard was submitted by standards committee B1 to the Secretariat and the American National Standards Institute. It was approved and formally designated as an American National Standard on February 4,1983. Copyright ASME International Provided by IHS und
18、er license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-ASME STANDARDS COMMITTEE BI Standardization and Unification of Screw Threads (The following is the roster of the Committee at the time of approval of this Standard.) OFFICERS D. J. Emanuelli, Chairma
19、n H. W. Ellison, Vice Chairman C. E. Lynch, Secretary COMMITTEE PERSONNEL AEROSPACE INDUSTRIES ASSOCIATION OF AMERICA, INC. G. G. Gerber, McDonnell Douglas, St. Louis, Missouri H. Borrman, Alternate, Sperry Gyroscope Division, Great Neck, New York AMERICAN IRON AND STEEL INSTITUTE F. Dallas, Jr., Sa
20、whill Tubular Division, Sharon, Pennsylvania AMERICAN MEASURING TOOL MANUFACTURERS ASSOCIATION D. Dodge, Pennoyer-Dodge Company, Glendale, California C. W. Jatho, Alternate, American Measuring Tool Manufacturers Association, Birmingham, Michigan AMERICAN PIPE FITTINGS ASSOCIATION W. C. Farrell, Stoc
21、kham Valves and Fittings, Birmingham, Alabama DEFENSE INDUSTRIAL SUPPLY CENTER E. Schwartz, Defense Industrial Supply Center, Philadelphia, Pennsylvania F. S. Ciccarone, Alternate, Defense Industrial Supply Center, Philadelphia, Pennsylvania ENGINE MANUFACTURERS ASSOCIATION G. A. Rua, Cummins Engine
22、 Company, Columbus, Indiana FARM AND INDUSTRIAL EQUIPMENT INSTITUTE J. F. Nagy, Ford Motor Company, Dearborn, Michigan INDUSTRIAL FASTENERS INSTITUTE R. B. Belford, Industrial Fasteners Institute, Cleveland, Ohio R. M. Harris, Bethlehem Steel Company, Lebanon, Pennsylvania K. E. McCullough, SPS Tech
23、nologies, Inc., Jenkintown, Pennsylvania J. C. McMurray, Russell, Burdsall and Ward Inc., Mentor, Ohio J. A. Trilling, Holo-Krome Company, West Hartford, Connecticut E. D. Spengler, Alternate, Bethlehem Steel Company, Lebanon, Pennsylvania MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTI
24、NG INDUSTRY W. C. Farrell, Stockham Valves and Fittings, Birmingham, Alabama METAL CUTTING TOOL INSTITUTE (TAP ., Columbus, Indiana A. D. Shepherd, Jr., Litton Union/Butterfield, Derby Line, Vermont A. G. Strang, Boyds, Maryland J. Turton, The Bendix Corp., Inc., Greenfield, Massachusettts - vi a Co
25、pyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-ASME B1*20-1 83 W 2575512 0011847 4 W . CONTENTS Foreword Standards Committee Roster . Introduction . 1.1 Scope . 1.3 Sealing . 1.4 Inspection E . 1.5 Ap
26、pendix . 1.6 Related Standard American National Standard Pipe Thread Form 2.1 Thread Form . 2.2 Angle of Thread . 2.3 Trncation and Thread Height . 3.1 Taper Pipe Threads . 1.2 Thread Designations Specification for General Purpose Taper Pipe Threads, NPT 3.2 Tolerances Specifications for Internal St
27、raight Threads in Pipe Couplings. NPSC 4.1 Straight Pipe Threads in Pipe Couplings Specifications for Railing Joint Taper Pipe Threads. NPTR 5.1 Railing Joints Specifications for Straight Pipe Threads for Mechanical Joints; NPSM.NPSL. NPSH 6.1 Straight Pipe Threads . 6.2 Free-Fitting Mechanical Join
28、ts for Fixtures, NPSM 6.3 Loose-Fitting Mechanical Joints With Locknuts, NPSL . 6.4 Loose-Fitting Mechanical Joints for Hose Coupling, NPSH . Gages and Gage Tolerances for American National Standard Pipe Threads 7.1 7.2 7 -3 7.4 Design of Gages . I . Classes of Gages . Gage Tolerances . Relation of
29、Lead and Angle Deviations to Pitch Diameter Tolerances of Gages vii iii iv 1 1 1 1 1 1 1 4 4 4 4 4 4 9 9 9 9 9 13 13 13 13 16 16 16 16 18 18 Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-ASME BI-20
30、91 83 W 2575532 0033848 b W ! 8 Gaging of Taper Pipe Threads 18 8 . 1 Gaging External Taper Threads . 18 8.2 Gaging Internal Taper Threads . 18 8.3 Gaging Practice . 18 8.4 Gaging Chamfered. Countersunk. or Recessed Threads . 18 9 Gaging of Straight Pipe Threads 22 9.1 Types of Gages . 22 9.2 Gage D
31、imensions 22 Figures 1 Basic Form of American National Standard Taper Pipe Thread 2 2 American National Standard Taper Pipe Threads for Pressure-Tight Joints. NPT 4 4 NPT Standard Taper Pipe Thread Plug and Ring Gages . 14 3 American National Standard Taper Pipe Thread Notation 5 5 Suggested Form of
32、 Gage Thread 14 6 Gaging External Taper Threads With Ring Gage 14 7 Gaging Internal Taper Threads . 14 8 Gaging of Chamfered Threads . 15 Tables 1 8 9 10 11 Limits on Crest and Root Truncation of American National Standard External and Internal Taper Pipe Threads. NPT 3 Basic Dimensions of American
33、National Standard Taper Pipe Thread. NPT 6 Tolerances on Taper. Lead. and Angle of Pipe Threads. NPT . 8 Dimensions. Internal Straight Threads in Pipe Coupling. NPSC 8 Dimensions of External and Internal Taper Pipe Threads for Railing Joints. NPTR . 10 Dimensions of External and Internal Straight Pi
34、pe Threads for Fixtures. NPSM . 11 Dimensions. External and Internal Straight Pipe Thread for Locknut Connections. NPSL 12 Basic Dimensions of Threaded Plug and Ring Gages for National American National Standard Taper Pipe Threads. NPT 17 Tolerances for American National Standard Working Taper Pipe
35、Thread Plug and RingGages. NPT 19 Diameter Equivalent of Deviation in Half Included Angle of Thread for ToolsandGages 20 Diameter Equivalent of Deviation in Lead for Tools and Gages 21 Appendix 23 Viii Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction
36、or networking permitted without license from IHS-,-ANSllASME 81.20.1-1983 AN AMERICAN NATIONAL STANDARD PIPE THREADS, GENERAL PURPOSE (INCH) 1 INTRODUCTION 1.1 Scope This American National Standard covers dimen- sions and gaging of pipe threads for general purpose applications. 1.2 Thread Designatio
37、ns 1.2.1 The types of pipe threads included in this Standard are designated by specifying in sequence the nominal pipe size, number of threads per inch and the thread series symbol as follows: 3/8 - 18 NPT 1/2 - 14 NPTR 1/8 - 27 NPSM 1/8 - 27 NPSL 1/8 - 27 NPSC 1 -11.5NPSH For left hand threads add
38、LH to the designation, otherwise right hand threads will be understood. For example: 318 - 18 NPT - LH 1.2.2 Each of these letters in the symbols has a defrnite significance as follows: N = National (American) Standard P = Pipe T = Taper c = coupling S = Straight M = Mechanical L = Locknut H = Hose
39、Coupling R = Railing Fittings Where it is necesszy fo use decimal notation for the size designation (as when inserting such in a computer or elec- tronic accounting machine) the decimal equivalent of nom- inal pipe size may be substituted for fractional pipe sizes. 1.2.3 Coated or Plated Threads. Th
40、e threaded product specifications covered in this Standard do not include an allowance for coatings or plating. 1.3 Sealing 1.3.1 Where pressure-tight joints are required, it is intended that taper pipe threads conforming to this Standard be made up wrench-tight with a sealant. To prevent galling on
41、 certain piping materials such as stainless steels, the sealant usually contains a lubricant. 1.3.2 Pipe threads designed for pressure-tight joints that may be used without sealing compounds (Dryseal Threads) are covered in ANSI B1.20.3 (Inch) and ANSI Bl.20.4 (Metric Translation). 1.4 Inspection A
42、gaging method and tolerances are prescribed in this Standard to effect a functional inspection of the handtight L1 engagement threads. However, con- formance to this Standard requires that all basic design dimensions be met (within applicable toler- ances) including extension of the thread elements
43、to provide for wrench-tight makeup. Therefore, addi- tional methods of gaging may be employed to evaluate conformance to the basic design dimensions. When additional methods of gaging are employed, they shall be agreed upon by the supplier and the purchaser. 1.5 Appendix Useful and supplementary inf
44、ormation which is not a part of this Standard is presented in the Appen- dix. Specifically, the Appendix gives Suggested Twist Drill Diameters for Drilled Hole Sizes for Pipe Threads. 1.6 Related Standard Definitions of terms and symbols for thread di- mensions are given in ANSI B1.7, Nomenclature,
45、Definitions and Letter Symbols for Screw Threads. 1 Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-AN AMERICAN NATIONAL STANDARD PIPE THREADS, GENERAL PURPOSE (INCH) Axis +I+ External Thread ANSI/AS
46、ME B1.20.1-1983 .I +P- Internal Thread NOTATION H = 0.866025 = height of 60 deg. sharp V thread 0 = 1 deg. 47 min. = thread taper angle for 1/16 taper h = 0.80000 = height of thread on product fc = depth of truncation at crest p = l/n = pitch (measured parallel to axis) f, = depth of truncation at r
47、oot n = number of threads per inch F, = width of flat at crest (Y = 30deg. = thread flank angle F, = width of flat at root GENERAL NOTE: For a symmetrical straight screw thread, H = cot (u12n. For a symmetrical taper screw thread, H = (cot (Y - tan2 tan (Y)/2n, so that the exact value for an America
48、n National Standard taper pipe thread is H = 0.865743 as against H = 0.866025p, the value given above. For an 8-pitch thread, which is the coarsest standard taper pipe thread pitch, the corresponding values of H are 0.108218 and 0.108253 respectively, the difference being 0.000035 inch. This differe
49、nce being too small to be significant, the value of H = 0.866025 continues in use for threads of 0.750 in., or less, taper/ft on the diameter. FIG. 1 BASIC FORM OF AMERICAN NATIONAL STANDARD TAPER PIPE THREAD 2 Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-Internal Thread 1 w External Thread TABLE 1 LIMITS ON C
