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JJG 672-2018 English PDFStandard Briefing:Stadard ID: JJG 672-2018Stadard Title: Bomb Calorimeters Price (USD): 419 Lead day (Deliver True-PDF English version): 4 days Status: Valid Evolution and Historical Versions:
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Contents, Scope, and Excerpt:JJG 672-2018 Bomb Calorimeters National Metrology Verification Regulations of the People's Republic Oxygen bomb calorimeter Published on.2018-12-25 2019-06-25 implementation State Market Supervisory Administration released Oxygen bomb calorimeter verification procedure Replace JJG 672-2001 Focal Point. National Physical and Chemical Metrology Technical Committee Main drafting unit. China Institute of Metrology Participated in the drafting unit. Hunan Institute of Metrology and Inspection This procedure entrusts the National Physical and Chemical Metrology Technical Committee to explain The main drafters of this procedure. Wang Haifeng (China Institute of Metrology) Li Jia (China Institute of Metrology) Meng Fanmin (China Institute of Metrology) Participate in the drafters. Thursday Qing (Hunan Province Metrology and Testing Institute) table of Contents Introduction (II) 1 range (1) 2 References (1) 3 terms (1) 4 Overview (1) 5 Metrological performance requirements (2) 6 General technical requirements (2) 6.1 Legal measurement management signs and signs (2) 6.2 Appearance requirements (2) 6.3 Oxygen bomb safety performance requirements (2) 7 measuring instrument control (2) 7.1 Verification conditions (2) 7.2 Verification items and verification methods (3) 7.3 Processing of verification results (5) 7.4 Verification cycle (5) Appendix A Thermal Capacity Calibration Method for Oxygen Bomb Calorimeter (6) Appendix B Calculation Method of Caloric Value of Benzoic Acid (9) Appendix C Oxygen Bomb Calorimeter Calibration Original Record Format (10) Appendix D Verification certificate/verification result notice page format (11) introduction Compared with JJG 672-2001, the main technical contents except for editorial changes are as follows. --- Added introduction; --- Added reference files (see 2); --- Added terminology (see 3); --- Cancel the "stirring heat", "heat capacity repeatability" and "balance point stability" verification project; --- Added "heat value repeatability" verification project (see Table 1); --- Revised the "heat value indication error" verification project (see Table 1); --- Cancel the "temperature measurement system requirements" in the general technical requirements; --- Revised the "method of verification of calorific value error" (see 7.2.3); --- Added "validation method for calorific value repeatability" (see 7.2.4); --- Added "thermal capacity calibration method for oxygen bomb calorimeter" (see Appendix A); --- Added "calculation method for calorific value of benzoic acid" (see Appendix B); --- Added "Oxygen Bomb Calorimeter Calibration Original Record Format" (see Appendix C); --- Added "Verification Certificate/Verification Result Notice Page Format" (see Appendix D). The previous release of this procedure. ---JJG 672-2001; ---JJG 672-1990 and JJG 673-1990. Oxygen bomb calorimeter verification procedureScopeThis procedure applies to the first verification, subsequent verification and in-use inspection of isothermal and adiabatic oxygen bomb calorimeters. 2 reference files This procedure refers to the following documents. GB/T 213-2008 Determination method of calorific value of coal MT/T 737 calorimeter oxygen bomb safety performance inspection specification For dated references, only dated versions apply to this Code; any undated quotation The latest version (including all amendments) applies to this procedure. 3 terms Calorimeter heat capacity heatcapacityofthecalorimeter Referred to as heat capacity, it refers to the heat required to generate a unit temperature rise in a calorimetric system, usually in joules per Kelvin (J/K). Said. 4 Overview Oxygen bomb calorimeters are meters used to measure the heat of combustion of solid and liquid fuels. The structure of the oxygen bomb calorimeter is shown in the figure 1 is shown. The measurement principle is that a certain amount of sample is burned in an oxygen bomb filled with excess oxygen, and the heat released makes the whole The calorimetric system (including the oxygen bomb, the water in the inner cylinder and the inner cylinder, the agitator and the thermometer) rises in temperature; then according to the heat Calculate the calorific value of the sample by measuring the heat capacity, the temperature rise of the calorimetric system, and the sample quality. Heat capacity of oxygen bomb calorimeter It is determined by burning a certain amount of benzoic acid combustion heat standard substance under similar conditions. Oxygen bomb calorimeters can be divided into isothermal and adiabatic types from the calorimetric principle. The calorimetric system of the isothermal oxygen bomb calorimeter is charged Surrounded by a water-filled outer cylinder that maintains a constant temperature. The sample burns in the oxygen bomb to raise the temperature of the calorimetric system while The outer cylinder water temperature remains unchanged. The calorimetric system of the adiabatic oxygen bomb calorimeter is filled with water and the temperature can change rapidly. Surrounded by. The sample burns in the oxygen bomb to raise the temperature of the calorimetric system, and the temperature of the outer cylinder automatically tracks the temperature of the inner cylinder, so that There is no heat exchange between the inner and outer cylinders. ...... |