1、AN AMERICAN NATIONAL STANDARDTest UncertaintyASME PTC 19.1-2005(Revision of ASME PTC 19.1-1998)Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-This is Job # 000608 $FM Electronic Page#1of10PL:PTCF
2、 Except 9999ASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Date of Issuance: October 13, 2006The 2005 edition of ASME PTC 19.1 will
3、be revised when the Society approves the issuance ofthe next edition. There will be no Addenda issued to ASME PTC 19.1-2005.ASME issues written replies to inquiries as code cases and interpretations of technical aspectsof this document. Code cases and interpretations are published on the ASME websit
4、e underthe Committee Pages at http:/www.asme.org/codes/ as they are issued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards. The Standards Committee
5、that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comment that provides an opportunity for additional public input from industr
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7、ment, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assumes any such liability. Users of a code or standard are expresslyadvised that determination of the validity of any such patent rights, and the risk of infrin
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10、he American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2006 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.This is Job # 000608 $FM Electronic Page#2of10 PL:PTCF 9996ASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 1
11、8.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-CONTENTSNotice viiForeword viiiCommittee Roster . ixSection 1 Introduction 11-1 General . 11-2 Harmonization With International Standards . 11-3
12、 Applications . 1Section 2 Object and Scope 22-1 Object. 22-2 Scope . 2Section 3 Nomenclature and Glossary 33-1 Nomenclature 33-2 Glossary. 3Section 4 Fundamental Concepts 54-1 Assumptions . 54-2 Measurement Error 54-3 Measurement Uncertainty 54-4 Pretest and Posttest Uncertainty Analyses 11Section
13、5 Defining the Measurement Process 135-1 Overview 135-2 Selection of the Appropriate “True Value” . 135-3 Identification of Error Sources . 135-4 Categorization of Uncertainties 155-5 Comparative Versus Absolute Testing. 16Section 6 Uncertainty of a Measurement 176-1 Random Standard Uncertainty of t
14、he Mean 176-2 Systematic Standard Uncertainty of a Measurement . 186-3 Classification of Uncertainty Sources 196-4 Combined Standard and Expanded Uncertainty of aMeasurement. 19Section 7 Uncertainty of a Result . 227-1 Propagation of Measurement Uncertainties Into a Result 227-2 Sensitivity . 237-3
15、Random Standard Uncertainty of a Result . 237-4 Systematic Standard Uncertainty of a Result 247-5 Combined Standard Uncertainty and Expanded Uncertainty of aResult. 247-6 Examples of Uncertainty Propagation . 24Section 8 Additional Uncertainty Considerations 288-1 Correlated Systematic Standard Unce
16、rtainties. 288-2 Nonsymmetric Systematic Uncertainty 318-3 Fossilization of Calibrations . 358-4 Spatial Variation 36iiiThis is Job # 000608 $FM Electronic Page#3of10 PL:PTCF Odd PageASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under lic
17、ense with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-8-5 Analysis of Redundant Means . 368-6 Regression Uncertainty. 38Section 9 Step-by-Step Calculation Procedure 419-1 General Considerations. 419-2 Calculation Procedure 41Section 10 Examples 4310-1 Flow
18、 Measurement Using Pitot Tubes. 4310-2 Flow Rate Uncertainty . 4710-3 Flow Rate Uncertainty Including Nonsymmetrical SystematicStandard Uncertainty 5010-4 Compressor Performance Uncertainty. 5110-5 Periodic Comparative Testing . 62Section 11 References . 69Section 12 Bibliography 71Figures4-2-1 Illu
19、stration of Measurement Errors . 64-2-2 Measurement Error Components. 74-3.1 Distribution of Measured Values (Normal Distribution) 84-3.3 Uncertainty Interval . 115-3.1 Generic Measurement Calibration Hierarchy . 145-4.3 Difference Between “Within” and “Between” Sources of DataScatter 167-6.2 Pareto
20、 Chart of Systematic and Random Uncertainty ComponentContributions to Combined Standard Uncertainty . 278-2.1 Schematic Relation Between Parameters CharacterizingNonsymmetric Uncertainty 328-2.2 Relation Between Parameters Characterizing NonsymmetricUncertainty 348-5.1 Three Posttest Cases . 3710-1.
21、1 Traverse Points (Example 10-1) 4410-2.1 Schematic ofa6in.H11547 4 in. Venturi. 4810-4.1 Typical Pressure and Temperature Locations for CompressorEfficiency Determination 5710-4.7 The h-s Diagram of the Actual and Isentropic Processes of anAdiabatic Compressor 6110-5.1-1 Installed Arrangement . 631
22、0-5.1-2 Pump Design Curve With Factory and Field Test Data Shown. 6410-5.1-3 Comparison of Test Results With Independent Control Conditions . 6410-5.2 Comparison of Test Results Using the Initial Field Test as theControl 67Tables6-4-1 Circulating Water Bath Temperature Measurements (Example6-4.1) .
23、206-4-2 Systematic Uncertainty of Average Circulating Water BathTemperature Measurements (Example 6-4.1) 217-6.1-1 Table of Data (Example 7-6.1) . 257-6.1-2 Summary of Data (Example 7-6.1) 267-6.2-1 Table of Data (Example 7-6.2) . 267-6.2-2 Summary of Data (Example 7-6.2) 278-1 Burst Pressures (Exam
24、ple 8-1-1) 29ivThis is Job # 000608 $FM Electronic Page#4of10 PL:PTCF Even PageASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-8-6.4.
25、5 Systematic Standard Uncertainty Components for YDeterminedfrom Regression Equation. 409-2-1 Table of Data. 429-2-2 Summary of Data . 4210-1.2 Average Values (Example 10-1) 4410-1.3-1 Standard Deviations (Example 10-1) 4510-1.3-2 Summary of Average Velocity Calculation (Example 10-1) 4510-1.6 Stand
26、ard Deviation of Average Velocity (Example 10-1) 4610-1.9 Uncertainty of Result (Example 10-1) . 4810-2.1-1 Uncalibrated Case (Example 10-2) 4810-2.1-2 Absolute Sensitivity Coefficients in Example 10-2 (CalculatedNumerically) . 5010-2.1-3 Absolute Sensitivity Coefficients in Example 10-2 (Calculated
27、Analytically) . 5110-2.1-4 Absolute Contributions of Uncertainties of Independent Parameters(Example 10-2: Uncalibrated Case) 5210-2.1-5 Summary: Uncertainties in Absolute Terms (Example 10-2:Uncalibrated Case) 5210-2.1.1-1 Relative Uncertainty of Measurement (Example 10-2: UncalibratedCase) . 5210-
28、2.1.1-2 Relative Contributions of Uncertainties of Independent Parameters(Example 10-2: Uncalibrated Case) 5310-2.1.1-3 Summary: Uncertainties in Relative Terms for the UncalibratedCase 5310-2.1.1-4 Relative Uncertainties of Independent Parameters (Example 10-2:Calibrated Case) 5310-2.1.1-5 Relative
29、 Contributions of Uncertainties of Independent Parameters(Example 10-2: Calibrated Case) 5410-2.1.1-6 Summary: Uncertainties in Relative Terms for the CalibratedCase 5410-2.1.1-7 Summary: Comparison Between Calibrated and UncalibratedCases . 5410-3-1 Absolute Contributions of Uncertainties of Indepe
30、ndent Parameters(Example 10-3: Uncalibrated, Nonsymmetrical SystematicUncertainty Case) . 5510-3-2 Summary: Uncertainties in Absolute Terms (Example 10-3:Uncalibrated, Nonsymmetrical Systematic Uncertainty Case) 5610-4.1-1 Elemental Random Standard Uncertainties Associated With ErrorSources Identifi
31、ed in Para. 10-4.2 . 5610-4.1-2 Independent Parameters 5710-4.1-3 Calculated Result . 5710-4.3.2-1 Inlet and Exit Pressure Elemental Systematic StandardUncertainties . 5810-4.3.2-2 Inlet and Exit Temperature Elemental Systematic StandardUncertainties . 5910-4.7 Evaluation of Analysis Error 6210-5.1-
32、1 Pump Design Data (Tcp 20C) 6310-5.1-2 Summary of Test Results . 6310-5.2-1 Uncertainty Propagation for Comparison With IndependentControl 6610-5.2-2 Summary: Uncertainties in Absolute Terms 6610-5.2-3 Summary of Results for Each Test 66vThis is Job # 000608 $FM Electronic Page#5of10 PL:PTCF Odd Pa
33、geASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-10-5.3-1 Uncertainty Propagation for Comparative Uncertainty . 6810-5.3-2 Sensitivi
34、ty Coefficient Estimates for Comparative Analysis 68Nonmandatory AppendicesA Statistical Considerations 73B Uncertainty Analysis Models . 84C Propagation of Uncertainty Through Taylor Series . 87D The Central Limit Theorem 92viThis is Job # 000608 $FM Electronic Page#6of10 PL:PTCF Even PageASME Perf
35、ormance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-NOTICEAll Performance Test Codes must adhere to the requirements of ASME PTC 1, GeneralInstruc
36、tions. The following information is based on that document and is included here foremphasis and for the convenience of the user of the Supplement. It is expected that the Codeuser is fully cognizant of Sections 1 and 3 of ASME PTC 1 and has read them prior toapplying this Supplement.ASMEPerformanceT
37、estCodesprovidetestprocedureswhichyieldresultsofthehighestlevel of accuracy consistent with the best engineering knowledge and practice currentlyavailable. They were developed by balanced committees representing all concerned interestsand specify procedures, instrumentation, equipment-operating requ
38、irements, calculationmethods, and uncertainty analysis.When tests are run in accordance with a Code, the test results themselves, withoutadjustment for uncertainty, yield the best available indication of the actual performance ofthe tested equipment. ASME Performance Test Codes do not specify means
39、to comparethose results to contractual guarantees. Therefore, it is recommended that the parties to acommercial test agree before starting the test and preferably before signing the contract onthe method to be used for comparing the test results to the contractual guarantees. It isbeyond the scope o
40、f any Code to determine or interpret how such comparisons shall bemade.viiThis is Job # 000608 $FM Electronic Page#7of10 PL:PTCF Odd PageASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction o
41、r networking permitted without license from IHS-,-,-FOREWORDIn March 1979 the Performance Test Codes Supervisory Committee activated the PTC 19.1Committee to revise a 1969 draft of a document entitled PTC 19.1 “General Considerations.”The PTC 19.1 Committee proceeded to develop a Performance Test Co
42、de Instruments andApparatusSupplementwhichwaspublishedin1985asPTC19.1-1985,“MeasurementUncer-tainty,” and which was intendedalong with its subsequent editionsto provide a meansof eventual standardization of nomenclature, symbols, and methodology of measurementuncertainty in ASME Performance Test Cod
43、es.Work on the revision of the original 1985 edition began in 1991. The two-fold objectivewas to improve the usefulness to the reader regarding clarity, conciseness, and technicaltreatment of the evolving subject matter, as well as harmonization with the ISO “Guide tothe Expression of Uncertainty in
44、 Measurement.” That revision was published as PTC 19.1-1998,“TestUncertainty,” thenewtitlereflecting theappropriateorientationof thedocument.The effort to update the 1998 revision began immediately upon completion of that docu-ment.This 2005revision isnotable forthefollowing significantdepartures fr
45、omthe 1998text:(a) Nomenclature adopted for this revision is more consistent with the ISO Guide. Uncer-tainties remain conceptualized as “systematic” (estimate of the effects of fixed error notobserved in the data), and “random” (estimate of the limits of the error observed from thescatter of the te
46、st data). The new aspect is that both types of uncertainty are defined at thestandard-deviation level as “standard uncertainties.” The determination of an uncertaintyat some level of confidence is based on the root-sum-square of the systematic and randomstandard uncertainties multiplied times the ap
47、propriate expansion factor for the desiredlevel of confidence (usually “2” for 95%). This same approach was used in the 1998 revisionbut the characterization of uncertainties at the standard-uncertainty level (“standard devia-tion”) was not as explicitly stated. The new nomenclature is expected to r
48、ender PTC 19.1-2005 more acceptable at the international level.(b) There is greater discussion of the determination of systematic uncertainties.(c) There is new text on a simplified approach to determine the uncertainty of straight-line regression.ASME PTC 19.1-2005 was approved by the PTC Standards
49、 Committee on September 13,2005, and was approved as an American National Standard by the ANSI Board of StandardsReview on November 3, 2005.viiiThis is Job # 000608 $FM Electronic Page#8of10 PL:PTCF Even PageASME Performance Test Code PTC_19.1 08-28-06 06:31:01 Rev 18.02Copyright ASME International Provided by IHS under license with ASME Not for Resal
