1、ASME B89.1.17-2001MEASUREMENT OF THREADMEASURING WIRES AN AMERICAN NATIONAL STANDARDAN AMERICAN NATIONAL STANDARDMEASUREMENT OF THREAD MEASURING WIRESASME B89.1.17-2001Date of Issuance: March 15, 2002This Standard will be revised when the Society approves the issuance of anew edition. There will be
2、no addenda issued to this edition.ASME will issue written replies to inquiries concerning interpretations oftechnical aspects of this standard.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting t
3、he criteria forAmerican National Standards. The Standards Committee that approved the code or standardwas balanced to assure that individuals from competent and concerned interests have had anopportunity to participate. The proposed code or standard was made available for public reviewand comment th
4、at provides an opportunity for additional public input from industry, academia,regulatory agencies, and the public-at-large.ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device,or activity.ASME does not take any position with respect to the validity of any patent
5、rights asserted inconnection with any items mentioned in this document, and does not undertake to insure anyoneutilizing a standard against liability for infringement of any applicable letters patent, nor assumeany such liability. Users of a code or standard are expressly advised that determination
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7、ME accepts responsibility for only those interpretations of this document issued inaccordance with the established ASME procedures and policies, which precludes the issuanceof interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or o
8、therwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2002 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll Rights ReservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster vCommittee Corresp
9、ondence vii1 Scope 12 Definitions . 13 References . 14 General . 15 Classification . 25.1 2Master Wires 5.2 2Working Sets .6 Inch Series Specifications . 26.1 2Material .6.2 2Wire Design 6.3 2Wire Tolerances .6.4 3“Best-Size” Wires .6.5 4Wire Measurement Methods 7 Metric Series Specifications 57.1 5
10、Material .7.2 6Wire Design 7.3 6Wire Tolerances .7.4 6“Best-Size” Wires .7.5 6Wire Measurement Methods Figures1 Threading Measuring Wires 22 Measuring Instrument 7Tables1 “Best-Size” Wires for Inch Series 60 deg Threads . 32 ”Best-Size” Wires for Inch Series 29 deg Acme Threads 43 “Best-Size” Wires
11、for Inch Series 7/45 deg Buttress Threads . 44 Thread Wire Measurement Specifications 55 “Best-Size” Wires for Metric Series 60 deg Threads . 76 Thread Wire Measurement Specifications 7Nonmandatory AppendicesA Measurement of Balls 9B Examples of Uncertainty Budgets for Thread Wire Measurements 11iii
12、FOREWORDThis Standard is the result of the combined work of members of the ASME B1 ScrewThread Committee and the ASME B89 Dimensional Metrology Committee. It is theresponsibility of the B1 Committee to determine how the pitch diameter of threads ismeasured. The B89 Dimensional Metrology Committee wr
13、ites standards on specificationsand procedures for dimensional measuring equipment. Thread wires differ from most itemsmeasured in that they are measured in a deformed condition to approximate the elasticdeformation that occurs when they are used to measure pitch diameter.For this reason when using
14、this Standard it is necessary to ensure that the B1 standardsreferenced in this document are the latest edition of the B1 standard which specifies theconditions to be used when measuring the pitch diameters of threads.The measurement of thread measuring balls is included as an appendix to the standa
15、rd.This edition of B89.1.17 was approved by the American National Standards Institute onOctober 24, 2001.ivASME B89 STANDARDS COMMITTEEDimensional Metrology(The following is the roster of the Committee at the time of approval of this Standard.)OFFICERSR. B. Hook, ChairM. Lo, SecretaryCOMMITTEE PERSO
16、NNELD. Beutel, Caterpillar, Inc.K. L. Blaedel, University of CaliforniaJ. B. Bryan, Bryan AssociatesT. Carpenter, U.S. Air ForceT. Charlton, Brown and Sharpe ManufacturingR. J. Hocken, University of North CarolinaR. B. Hook, MetconM. Liebers, Professional Instruments Co.M. Lo, The American Society o
17、f Mechanical EngineersB. Parry, Boeing Co.F. G. Parsons, Federal Products Co.B. R. Taylor, Renishaw PLCR. C. Veale, National Institute of Standards and Technology (Retired)SUBCOMMITTEE B89.1 LENGTHR. C. Veale, Chair, National Institute of Standards and Technology (Retired)D. Carlson, L. S. StarrettD
18、. Christy, Federal Products Co.T. D. Doiron, National Institute of Standards and TechnologyD. D. Friedel, L. S. StarrettC. J. Fronczek, Jr., National Institute of Standards and TechnologyM. R. Hamar, Hamar Laser Instruments, Inc.D. T. Harris, Southern Gage, Inc.G. L. Vander Sande, U.S. Army Armament
19、s ResearchW. A. Watts, Southern Gage, Inc.WORKING GROUP B89.1.17 MEASUREMENT OF THREADMEASURING WIRESR. C. Veale, Chair, National Institute of Standards and Technology (Retired)A. Barrows, KennametalL. Dixon, Jr., General ElectricR. Dodge, Pennoyer-DodgeT. D. Doiron, National Institute of Standards
20、and TechnologyD. T. Harris, Southern Gage, Inc.R. Iavelli, Deltronic Corp.L. Johnson, Johnson GagesJ. Kane, Boeing Co.R. Knittel, Leitech U.S., Ltd however, they should not contain proprietary names orinformation.Requests that are not in this format will be rewritten in this format by the Committeep
21、rior to being answered, which may inadvertently change the intent of the original request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation that might affect an interpretation is available. Further, persons aggrieved byan interpretation may appeal to
22、the cognizant ASME Committee or Subcommittee. ASMEdoes not “approve,”“certify,”“rate,” or “endorse” any item, construction, proprietary device,or activity.Attending Committee Meetings. The B89 Main Committee regularly holds meetings, whichare open to the public. Persons wishing to attend any meeting
23、 should contact the Secretaryof the B89 Main Committee.viiASME B89.1.17-2001MEASUREMENT OF THREAD MEASURING WIRES1 SCOPEThis Standard is intended to establish uniform prac-tices for the measurement of thread measuring wires.The standard includes methods for the direct measure-ment of both master and
24、 working wires, and methodsfor the comparison measurement of working wires. Thestandard includes requirements for geometric qualitiesof thread measuring wires, the important characteristicsof the comparison equipment, environmental conditions,and the means to ensure that measurements are madewith an
25、 acceptable uncertainty level.Wires covered by the standard include inch series60-deg, 29-deg Acme, 7/45-deg Buttress, and metric60-deg threads.2 DEFINITIONS“best-size” wire: the size of a wire that would touchat the pitch cylinder on a thread of zero lead angle.“C” constant: a constant to be subtra
26、cted from themeasurement over the wires to give the pitch diameter.measurement uncertainty: parameter associated withthe result of a measurement that characterizes thedispersion of the values that could reasonably be attrib-uted to the measurand (quantity being measured).3 REFERENCESThe following do
27、cuments form a part of this Standardto the extent specified herein. The latest issue shallapply.ASME B1.2, Gages and Gaging for Unified Inch ScrewThreadsASME B1.5, Acme Screw ThreadsASME B1.7M, Nomenclature, Definitions, and LetterSymbols for Screw ThreadsASME B1.8, Stub Acme Screw ThreadsASME B1.9,
28、 Buttress Inch Screw Threads 7/45 FormWith 0.6 Pitch Basic Height of Thread EngagementASME B1.16M, Gages and Gaging for Metric M ScrewThreadsASME B1.22M, Gages and Gaging for MJ SeriesMetric Screw Threads1ASME B1.30M, Screw Threads Standard Practicefor Calculating and Rounding DimensionsPublisher: T
29、he American Society of Mechanical Engi-neers (ASME), Three Park Avenue, New York, NY10016-5990; Order Department: 22 Law Drive, Box2900, Fairfield, NJ 07007-2900Federal Specification GGG-W-366b, Federal Specifica-tion Wire, Measuring: Gear, Thread, and GeneralPurpose, General Services Administration
30、, Washing-ton, DC, May 8, 1967 (canceled)Guide to the Expression of Uncertainty in MeasurementPublisher: International Organization for Standardization(ISO), 1 rue de Varembe, Case Postale 56, CH-1211, Geneve, 20, Switzerland/SuisseNIST Technical Note 1297, 1994 Edition, Guidelinesfor Evaluating and
31、 Expressing the Uncertainty ofNIST Measurement ResultsPuttock, M. J. and Thwaite, E. G., “Elastic Compressionof Spheres and Cylinders at Point and Line Contact,”National Standards Laboratory Technical Paper No.25, Commonwealth Scientific and Industrial ResearchOrganization (CSIRO), Australia, 19694
32、GENERALWhen the pitch diameter of external threads is mea-sured using thread wires, good repeatability is onlyobtained when a sufficient force is used to push thewires against the sides of the thread flank. Elasticdeformation occurs between the wires and thread flankswhen the pitch diameter is measu
33、red in this manner.The practice in the United States is to measure thewires with a method that approximately reproduces thedeformation that occurs between the thread and thewires. For the thread series listed in this Standard, theASME B1 Committee has standardized the forces tobe used when measuring
34、 pitch diameter. In measuringthe pitch diameter of internal threads, and in somecases external threads, balls rather than wires are used.The use of balls for measuring pitch diameter is dis-cussed in Appendix A.MEASUREMENT OF THREAD MEASURING WIRESASME B89.1.17-2001PGENERAL NOTES:(a) P is the pitch.
35、(b) H9251 is the half-angle.FIG. 1 THREADING MEASURING WIRES5 CLASSIFICATIONWires may be classified by their use as masters orworking wires and by inch or metric series.5.1 Master WiresMaster wires contain only one wire per pitch. Thewires are used to measure working wires or, in somecases, other ma
36、ster wires.5.2 Working SetsWires meant for measuring the pitch diameter ofthreaded gages or products consist of a three-wire setfor each pitch. The wires may be measured either bycomparison to a master, which has been measured inaccordance with this Standard, or by directly measuringthe wires in the
37、 manner described in the standard. SeeFig. 1.6 INCH SERIES SPECIFICATIONSThe material and design specifications for all masterand working wires are the same, except that the workingwires, which are three-wire sets, have a requirementthat the variation in diameter among the three wiresmay not exceed
38、a specified amount. A correction factor(“C” constant) must also be calculated and placed onthe label for all except 29-deg Acme wires.6.1 MaterialThe wires shall be made from alloy tool steel thathas been stabilized to ensure dimensional stability. The2wires shall be free from cracks and other detri
39、mentaldefects. The hardness shall be a minimum of 62 onthe Rockwell C scale. The surface finish shall notexceed 2 H9262in. Ra, using a 0.03-in. cutoff.6.2 Wire DesignA set of measuring wires shall consist of three wiresfor each pitch, except for master wires, which containone wire for each pitch. Th
40、e length of the thread wiresshall be a minimum of 1 in. Variations in the lengthof the three wires in any set shall not exceed 0.1 in.6.3 Wire TolerancesIn order to accurately measure the pitch diameter ofthreaded gages and thread products, it is necessary tohave accurate measurements of the wires.
41、For example,an error of one unit in the mean diameter of threadmeasuring wires will cause an error of three units (for60-deg threads) when measuring pitch diameter.6.3.1 Master Wires. Diameters of master wiresneed to be known, in most cases, with an uncertaintyof 5 H9262in. or less. The diameter of
42、the wires shall bewithin 20 H9262in. of the “best-size” as shown in the tablesor computed using the formulas in this document.The variations in diameter, including taper and out-of-roundness, shall not exceed 5 H9262in. over the central 0.5in. of the wire.6.3.2 Working Sets. A set of wires shall hav
43、ethe same diameter within 10 H9262in., and the averagediameter shall be within 20 H9262in. of the specified “best-size” wire. The variations in diameter of each wire,including taper and out-of-roundness, shall not exceed10 H9262in. over the central 1 in. of the wire. Each setshall display the TPI (t
44、hreads per in.) and the averagedeformed diameter. Except for 29-deg Acme, the calcu-lated wire constant (“C” constant), based on the mea-sured mean diameter, shall also be displayed. The “C”constant for symmetrical threads is computed from theformulaC p w (1 + cosec H9251) cot(H9251)/2nwherew p the
45、average of the setH9251 p the half-angle, andn p the number of threads per in.For 60-deg threads the formula reduces toMEASUREMENT OF THREAD MEASURING WIRES ASME B89.1.17-2001TABLE 1 “BEST-SIZE” WIRES FOR INCH SERIES 60 deg THREADSThreads “Best-Size” “C” Threads “Best-Size” “C”per in. Pitch, in. Wir
46、es Constants per in. Pitch, in. Wires Constants120 0.008333 0.004811 0.00722100 0.010000 0.005774 0.0086696 0.010417 0.006014 0.0090290 0.011111 0.006415 0.0096280 0.012500 0.007217 0.0108372 0.013889 0.008019 0.0120364 0.015625 0.009021 0.0135256 0.017857 0.010310 0.0154650 0.020000 0.011547 0.0173
47、248 0.020833 0.012028 0.0180444 0.022727 0.013122 0.0196840 0.025000 0.014434 0.0216536 0.027778 0.016038 0.0240632 0.031250 0.018042 0.0270630 0.033333 0.019245 0.0288728 0.035714 0.020620 0.0309327 0.037037 0.021383 0.0320826 0.038462 0.022206 0.0333124 0.041667 0.024056 0.0360822 0.045455 0.02624
48、3 0.0393620 0.050000 0.028868 0.0433018 0.055556 0.032075 0.0481116 0.062500 0.036084 0.0541314 0.071429 0.041239 0.0618613 0.076923 0.044412 0.0666212 0.083333 0.048113 0.0721711.5 0.086957 0.050204 0.0753111 0.090909 0.052486 0.0787310 0.100000 0.057735 0.086609 0.111111 0.064150 0.096238 0.125000
49、 0.072169 0.108257.5 0.133333 0.076980 0.115477 0.142857 0.082479 0.123726 0.166667 0.096225 0.144345.5 0.181818 0.104973 0.157465 0.200000 0.115470 0.173214.5 0.222222 0.128300 0.192454 0.250000 0.144338 0.216513.5 0.285714 0.164957 0.247443.25 0.307692 0.177646 0.266472.75 0.363636 0.209946 0.314922.5 0.400000 0.230940 0.346412 0.500000 0.288675 0.43301CAUTION: “C” constants in the table are computed for the “best-size” wires. The “C” constant should always be computedusing the actual wire size.GENERAL NOTE: See ASME B1.2 for limitations on using “C” constant values in pitc
