JJG 172-1994 Calibration Procedure for Inclined Micromanometers JJG172-1994 Standard download decompression password: www.bzxz.net
This procedure is applicable to the calibration of newly manufactured, in-use and repaired inclined micromanometers.
Some standard content:
Tilting Micromanometer Verification RegulationbzxZ.net JJG172-—1994 Verification Regulation for Tilting Micromanometer Verification Regulation for Tilting Tube Micromanometer JIG172-1991 This verification regulation was approved by the State Administration of Technical Supervision on January 5, 1994, and was implemented from December 1994. Responsible unit: Shanghai Municipal Bureau of Technical Supervision Drafting unit: Shanghai Municipal Bureau of Technical Evaluation and Research This type of technical provisions shall be interpreted separately. The main beneficiaries of this procedure are: Shanghai Metrology Technology Research and Efficiency Institute; Technical requirements Verification conditions Verification and verification methods Processing of verification results and verification period ...... Appendix 1 Verification record of inclined micromanometer Appendix 2 Verification record of China's signed instrument for reducing the weight of the acceleration () Verification procedure of inclined micromanometer This procedure is suitable for the new production and verification of the inclined micromanometer (hereinafter referred to as the "micromanometer") used in the peak layer. A kind of measuring instrument that uses the height difference of the liquid to measure the long force: its standard is a scientific tube with a certain degree of horizontality formed by drawing a measuring tube. The smaller liquid is converted into a proportional meter. This micromanometer is used to measure the small amount of ethanol in the gas level and has two technical requirements: 1. Appearance 1.1 The parts of the micromanometer are semi-solid: there must be no combustion and lock damage; 1.2 The glass body of the micromanometer (hereinafter referred to as the base tube) should not have defects that affect the accuracy and reading, and the internal organs should be eliminated. 1. The scale lines on the micromanometer are clear, and the lengths of the long, medium and short scale lines are reliable and correct, and are perpendicular to the center line of the measuring tube. This practice should not have any new phenomena; the scale changes in sensitivity under large and small scales. 1.4 The mathematical points on the micromanometer scale are complete and clean. 1.5 The micromanometer should be equipped with a water injector, and the table micromanometer should also have a horizontal adjustment device. 1.6 The multi-directional reading of the micromanometer should have obvious markings. 1.70.5 The continuous micromanometer reading should be stable, without jamming, jumping or loosening. 18 Micro-pressure adjustment device. 1.9 The micromanometer should have a brand. The brand shall be marked with the product name, matching number, manufacturer's name or degree mark, number, manufacturing date, pressure measurement range, gauge unit, accuracy level, working liquid rate at 20 ℃ (the gauge with the working liquid density included may not be marked) and the maximum upper working pressure. 2. The sealing performance The micromanometer should be able to withstand the maximum working pressure and last for 1 hour. There shall be no positive and negative drops within the maximum working pressure. 3. The accuracy of the equipment The accuracy grades of micromanometers are shown in Table 1 and are expressed in some terms: Table 1 Accuracy grades of micromanometers are shown in Table 1. 4.1 Standard calibration conditions (%) Accuracy grades of micromanometers can be used to develop standard micromanometers, comprehensive liquid micromanometers or other point force instruments with similar accuracy grades. The absolute value of the standard instrument’s allowable deviation is not greater than 1:4.2 Other equipment 4.2.1 Liquid stop 1; the state pad range should be 1 to 1.5 times the size of the manometer, the accuracy should not be lower than 2.5 level, the value should not be less than 1mA: Thermometer: Display range 0-50, the graduation value is 0.51:4.2.2 Rate change: The graduation value is 0.5kg/ml: : The upper limit of 5 or 00l can be used for the pressure regulator of the acid pressurized flow, Timer. The working liquid of the micromanometer is 810k/ (G679 stipulates that its volume white fraction is %). The micromanometer should be in the following three working conditions. The system cannot be calibrated. The specified temperature is 20=5℃, temperature fluctuation: during the whole calibration process, generally should not exceed 0.5℃, not more than 2℃, and the micrometer should be left at the specified temperature for more than 2h before calibration. The four calibration items and calibration methods 7 Appearance inspection The inspection should meet the requirements of Article 1 of this procedure. 8 Contraction and sealing inspection The tightness inspection is carried out under the condition that the micro-pressure is not full. Connect the reverse air connection, indicating nozzle, adapter, new roller dynamometer system seat (as shown in the figure) and then maintain the working pressure of the total pressure chamber at 15min. Observe the indication of the Srim liquid pressure gauge and the result should meet the requirements of Article 2 of this procedure 9 Verification of basic technical errors 9.! 9.1.1 Prepare the working liquid and determine the density of the micromanometer, as shown in Figure 9.1.2. Let the selected pressure regulator be clean, then flush the prepared working liquid into the pressure regulator, then use the reverse increase and decrease pressure method to expel the air in the pressure regulator until the micromanometer indication is stable, 9.14 Connect the two rubber nozzles to the standard and the positive (negative) nozzle of the micromanometer respectively, and at the same time connect the three nozzles of the pressure regulator with a rubber pipe. 9.1.5 In case of communication, adjust the level of the standard instrument and the micro-pressure to 9, 1.6 and use the method of direct comparison with the standard instrument. The calibration points are stepped within the scale range. For level 0.5, select 5 points, and for level below 0.5, select 3 points. The calibration procedure is to perform two calibrations in forward and reverse strokes: For micromanometers with adjustable strokes, the calibration should be carried out on the scale with an inclined number (update and adjust each time the center negative position is changed). After calibrating level 1.0 and level 1.5 pressure, the number should be reversed to 1/2 of the scale. When calibrating level 0.5 micro-stop timing, the reading should reach 10 of the scale value. During the calibration, the pressure increase and decrease should be slow and steady. After the calibration, the zero position should be recalibrated. If the zero position change exceeds 14% of the absolute value of the allowable error, it should be brought to the new correct position and calibrated again. For micromanometers marked with stop release, the above calibration method should be used and carried out on the scale with a relatively large stop. 9.2 Calculation of basic error 9.2.1 For a pressure gauge with 1a as the unit scale, the basic error (impact) of a micromanometer is calculated using formula (1): The indication of the micromanometer on a certain pressure range (P): The indication of the instrument (Pa): Micromanometer: The working pressure range indicated on the gauge plate (m): The upper limit of the micromanometer's measurement on the pressure range (P9.2.2 For a pressure gauge with a scale of -m units, the basic error is calculated using formula (2): % - + ing et*a. ++ × 100% Formula sinr"-micrometer slope constant (including working liquid density), "is the angle between the glass tube and the water surface: - the mark of the manometer on a certain inclined band (nt): - the average gravity value (m/2), L~-the upper limit of the measurement of the tested area minus the height value (mn). h, when the micrometer's inclined band number includes: as the filter density, then its absolute error is 6, calculated by formula (3) 100% Formula K-micromanometer frequency slope constant (including working liquid density), that is, sinα (m) 9.2.3 The maximum absolute error of each calibration point is in accordance with the provisions of Table 1: V. Control result processing and calibration cycle Micromanometers that have passed the calibration: White Monthly verification certificate: For micromanometers with small scale, the verification results are issued and the manometers with downgrade treatment are processed. For manometers with downgrade treatment, the accuracy grade mark must be changed, and the corresponding verification certificate must be issued. The verification period of the five-meter is determined by the specific use situation, but the length of the unit shall not exceed 1 year. Appendix Verification record sheet of inclined micromanometer Reverse verification year Manufacture! Accurate pressure grade When the temperature is not exceeded Standard pusher number Appearance: Density: Basic identification: Hui Xin Juice Morning West Indicator On the natural system density ..Nominal capacity of bamboo Shinong tAccording to the standard position Appendix 2 Verification total, Specification day Environmental protection level Regular process bed calculation Empty case Major cities in China's gravity acceleration (g) (n: Performance 1 standard reading effect Harleson Shadow Nai [1 Classic product Lulanlute Du Danjiang (anrs) 5 41341 : In this table, add the value of the project force in the area of the scale, and use the formula of Fnan to calculate the height of the full straight point: measure the degree of the place of measurement. and # 705: Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.