JJF 1840-2020 English PDFUS$529.00 · In stock
Delivery: <= 5 days. True-PDF full-copy in English will be manually translated and delivered via email. JJF 1840-2020: (Calibration specification for tire dynamic balance testing machine) Status: Valid
Basic dataStandard ID: JJF 1840-2020 (JJF1840-2020)Description (Translated English): (Calibration specification for tire dynamic balance testing machine) Sector / Industry: Metrology & Measurement Industry Standard Classification of Chinese Standard: A53 Word Count Estimation: 23,273 Date of Issue: 2020-07-02 Date of Implementation: 2021-01-02 Regulation (derived from): Announcement No. 29 (2020) of the State Administration for Market Regulation Issuing agency(ies): State Administration for Market Regulation JJF 1840-2020: (Calibration specification for tire dynamic balance testing machine)---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.(Calibration specification for tire dynamic balance testing machine) National Metrology Technical Specifications of the People's Republic of China Calibration specification for tire dynamic balance testing machine 2020-07-02 released 2021-01-02 implementation Issued by the State Administration for Market Regulation Calibration specification for tire dynamic balance testing machine Focal point. National Technical Committee of Vibration and Shock Speed Measurement Main drafting unit. Soft Control Co., Ltd. Double Star Group Co., Ltd. Wanli Tire Co., Ltd. Beijing Rubber Industry Research and Design Institute Co., Ltd. Participating in the drafting. Zhongce Rubber Group Co., Ltd. Fengshen Tire Co., Ltd. Triangle Tire Co., Ltd. China National Accreditation Center for Conformity Assessment This specification entrusts the National Technical Committee of Vibration and Shock Speed Measurement to be responsible for the interpretation The main drafters of this specification. Yu Mingjin (Soft Control Co., Ltd.) Zhang Chunying (Double Star Group Co., Ltd.) Li Guohua (Wanli Tire Co., Ltd.) Wang Xiguang (Beijing Rubber Industry Research and Design Institute Co., Ltd.) Participating drafters. Wang Qunfeng (Zhongce Rubber Group Co., Ltd.) Wang Lili (Fengshen Tire Co., Ltd.) Wang Bogang (Triangle Tire Co., Ltd.) Zhang Youwen (China National Accreditation Center for Conformity Assessment) table of ContentsIntroduction (Ⅲ) 1 scope (1) 2 Reference documents (1) 3 Terms and measurement units (1) 3.1 Static imbalance (1) 3.2 Static unbalanced mass (1) 3.3 Dynamic unbalance (2) 3.4 Unbalance of force couple (2) 3.5 Unbalanced mass of unilateral couple (2) 3.6 The unbalanced mass of the correction surface (2) 3.7 Surface separation ratio (3) 4 Overview (3) 5 Metering characteristics (4) 5.1 Test speed (4) 5.2 Test air pressure (4) 5.3 Unbalanced mass (4) 5.4 Surface separation ratio (4) 5.5 Key (or tap) marking angle (4) 5.6 Repeatability of testing machine without tire removal (4) 5.7 Test machine tire unloading measurement repeatability (5) 6 Calibration conditions (5) 6.1 Environmental conditions (5) 6.2 Measurement standards and other equipment (5) 7 Calibration items and calibration methods (5) 7.1 Calibration of test speed (5) 7.2 Calibration of test air pressure (6) 7.3 Calibration of unbalanced mass (6) 7.4 Calibration of surface separation ratio (6) 7.5 Calibration of key (or tap) marking angle (7) 7.6 Calibration of repeatability of testing machine without tire removal (7) 7.7 Calibration of test machine tire unloading measurement reproducibility (8) 8 Calibration result expression (8) 9 Recalibration interval (8) Appendix A Using the principle of equivalent calibration to calibrate unbalanced mass (9) Appendix B Retry (10) Appendix C Calibration Record of Tire Dynamic Balance Tester (11) Appendix D Contents of calibration certificate (calibration report) (15) Appendix E Examples of Uncertainty Evaluation for Unbalanced Mass Calibration (16)IntroductionJJF 1001 "General Measurement Terms and Definitions", JJF 1059.1 "Measuring Uncertainty Evaluation and Expression", JJF 1071 "Rules for Compiling National Metrology and Calibration Specifications" and GB/T 6326 "Tire Terms and Definitions" together constitute The basic series of standards for the formulation of this specification. The main technical reference compiled is GB/T 18505-2013 "Automobile Tire Dynamic Balance Test Method" and GB/T 25158-2010 "Tire Dynamic Balance Testing Machine". This specification is released for the first time. Calibration specification for tire dynamic balance testing machine1 ScopeThis specification applies to the calibration of car tires and truck tires dynamic balance testing machines (hereinafter referred to as testing machines).2 Reference documentsThis specification refers to the following documents. GB/T 18505-2013 Automobile tire dynamic balance test method GB/T 25158-2010 Tire dynamic balance testing machine For dated reference documents, only the dated version applies to this specification; for undated reference documents, The latest version (including all amendments) is applicable to this specification.3 Terms and units of measurement3.1 Static imbalance The product of tire mass multiplied by centroid eccentricity, expressed in g·cm. Note. 1 When the tire rotates at a certain speed, the static unbalance produces a centrifugal force perpendicular to the rotation axis, which can be expressed as follows. 2 As the tire deforms under the action of centrifugal force, the eccentricity of the center of gravity can be used as a function of the speed. [GB/T 18505-2013,3.2] 3.2 Static unbalanced mass The static imbalance is divided by the correction radius, and the unit is expressed in g. ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of JJF 1840-2020_English be delivered?Answer: Upon your order, we will start to translate JJF 1840-2020_English as soon as possible, and keep you informed of the progress. The lead time is typically 3 ~ 5 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of JJF 1840-2020_English with my colleagues?Answer: Yes. 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