[Daily question 20090331] Popularize instrument knowledge
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1. 1atm=( )Pa=( )mmH2O=( )mmHg( )kgf/cm2. 1 kgf/cm2=( )Pa=( )mmH2O=( )mmHg=( )atm. 2. How is the magnitude of pressure transmitted? 3. What are the possible reasons why the pointer of the spring tube pressure gauge does not return to zero? 4. How to determine the range of the pressure gauge? 5. When measuring steam pressure, what are the special requirements for the installation of pressure gauges? The first five people with correct answers will each be rewarded with 10 wealth, and the next five people with correct answers will each be rewarded with 5 wealth. Participants are rewarded. Don't copy other people's posts, otherwise you will be deducted 10 wealth. Summarize: 1. 1atm= (1.01325×105) Pa= (10332.3) mmH2O= (760) mmHg= (1.03323) kgf/cm2. 2. 1 kgf/cm2 = (9.80665×104) Pa = (10000) mmH2O = (735.562) mmHg = (0.967841) atm. 3. In order to ensure the uniformity of pressure measurement values, * * The metrology department preserves my country's pressure benchmark, which is the highest domestic standard for pressure measurement. At the same time, it is compared with the national defense pressure benchmark to achieve consistency in magnitude. The pressure magnitude is from * * Starting from the unit value of the pressure reproduced by the reference instrument, it is gradually transmitted to various types of pressure instruments for work through standard instruments and calibration methods at all levels. Working instruments are generally calibrated by direct comparison. 4. The measuring range of the instrument is determined according to the size of the pressure being measured. For elastic pressure gauges, when selecting the pressure gauge range, sufficient room must be left based on the properties of the medium being measured. Generally speaking, when measuring stable pressure, the maximum working pressure should not exceed 2/3 of the range. ； When measuring pulsating pressure, the maximum working pressure should not exceed 1/2 of the measuring range. ； When measuring high pressure, the maximum working pressure should not exceed 3/5 of the measuring range. ； To ensure accuracy, the minimum working pressure should not be less than 1/3 of the measuring range. 5. When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it. This post was last edited by Mobei Yihai on 2009-3-31 16:38 ]
1. 1atm＝（1013300）Pa＝（10330）mmH2O＝（760）mmHg（1.0332）kgf/cm2. 1 kgf/cm2 = (98070) Pa = (10000) mmH2O = (735.6) mmHg = (0.9678) atm. 2. How is the magnitude of pressure transmitted? Benchmark - First Class Standard - Second Class Standard - Third Class Standard - Working Instruments 3. What are the possible reasons why the spring tube pressure gauge pointer does not return to zero? The spring bend causes permanent deformation and loses elasticity ； The pointer and the central axis are loose, or the pointer is stuck ； The passage of the cock, pressure gauge connecting pipe or water trap is blocked. 4. How to determine the range of the pressure gauge? The measuring range of the pressure gauge is generally 1.5 to 3 times the working pressure of the equipment, preferably 2 times. 5. When measuring steam pressure, what are the special requirements for the installation of pressure gauges? When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1atm= 1013300 Pa=10330mmH2O=760mmHg=1.0332kgf/cm2. 1 kgf/cm2=98070Pa=10000mmH2O=735.6mmHg=0.9678atm. The measuring range of the pressure gauge is generally 1.5 to 3 times the working pressure of the equipment, preferably 2 times. I have just entered this industry and there is still a lot I don’t know. Let’s learn from everyone. * .
1. 1atm＝（1013300）Pa＝（10330）mmH2O＝（760）mmHg（1.0332）kgf/cm2. 1 kgf/cm2 = (98070) Pa = (10000) mmH2O = (735.6) mmHg = (0.9678) atm. 2. Benchmark - first-class standard - second-class standard - third-class standard - working instruments and meters 3. The spring bend causes permanent deformation and loses elasticity. ； The pointer and the central axis are loose, or the pointer is stuck ； The passage of the cock, pressure gauge connecting pipe or water trap is blocked. 4. The measuring range of the pressure gauge is generally 1.5 to 3 times the working pressure of the equipment, preferably 2 times. 5. When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1. 1atm= (1013300) Pa= (10330) mmH2O= (760) mmHg (1.0332) kgf/cm2. 1 kgf/cm2 = (98070) Pa = (10000) mmH2O = (735.6) mmHg = (0.9678) atm. atm standard atmospheric pressure Pa Pascal kgf/cm2. Engineering atmospheric pressure mmHg mmHg mmH2O mm water column 2. Accurate - first-class standard - second-class standard - third-class standard - working instrument 3. There are five reasons why the pointer does not return to zero.: 1) The fixed position of the movement is improper and the initial angle is too small. 2) The hairspring is not enlarged or coiled tightly enough. 3) The riveting of the pointer and the needle magazine is loose, and the coordination between the needle magazine and the central axis is loose. 4) The dial position is improperly fixed and displacement occurs. 5) The spring tube is severely deformed. 4. The upper limit of the pressure gauge = the maximum value of the measured pressure *4/3 5. When measuring steam pressure, an annular tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1. 1atm＝（1013300）Pa＝（10330）mmH2O＝（760）mmHg（1.0332）kgf/cm2. 1 kgf/cm2 = (98070) Pa = (10000) mmH2O = (735.6) mmHg = (0.9678) atm. 2. How is the magnitude of pressure transmitted? I am very ignorant. This is the first time I have seen "how the magnitude of pressure is transmitted." I don't know what it means. Please explain clearly and give a standard answer. I literally understand it as: After the spring tube of the pressure gauge is deformed under pressure, it transmits force to the central axis and drives the pointer to rotate. The value indicated by the pointer rotating at a certain position is the pressure measured by the pressure gauge. I don’t know if that’s right. 3. What are the possible reasons why the pointer of the spring tube pressure gauge does not return to zero? (1) The spring tube loses elasticity ； (2) The screw fixing the central axis is loose so that the pointer cannot rotate with the axis. ； (3) The pointer is stuck due to rust or something. ； (4) The pressure guide pipe is blocked or there is always pressure, and it needs to be drained and cleaned. ； 4. How to determine the range of the pressure gauge? (1) When measuring stable pressure, the normal operating pressure value is 1/2~2/3 of the upper limit of the instrument’s measuring range. ； (2) When measuring pulsating pressure (such as outlet pressure of pumps, compressors and fans), the normal operating pressure value should be 1/3~1/2 of the upper limit of the instrument’s measurement range. ； (3) When measuring high or medium pressure (greater than 4MPa), the normal operating pressure should not exceed 1/2 of the upper limit of the instrument’s measuring range. ； 5. When measuring steam pressure, what are the special requirements for the installation of pressure gauges? When measuring the pressure of water vapor and media with a temperature greater than 60°C, a condenser tube or siphon should be used.
1. 1atm= (1.01325×105) Pa= (10332.3) mmH2O= (760) mmHg= (1.03323) kgf/cm2. 1 kgf/cm2= (9.80665×104) Pa= (10000) mmH2O= (735.562) mmHg= (0.967841) atm. 2. How is the magnitude of pressure transmitted? answer: In order to ensure the uniformity of pressure measurement values, in * * The metrology department preserves my country's pressure benchmark, which is the highest domestic standard for pressure measurement. At the same time, it is compared with the national defense pressure benchmark to achieve consistency in magnitude. The pressure magnitude is from * * Starting from the unit value of the pressure reproduced by the reference instrument, it is gradually transmitted to various types of pressure instruments for work through standard instruments and calibration methods at all levels. Working instruments are generally calibrated by direct comparison. 3. What are the possible reasons why the pointer of the spring tube pressure gauge does not return to zero? answer: Possible reasons are: The pointer is bent, the hairspring torque is insufficient, the pointer is loose, the transmission gear has friction, the spring tube is clogged, there is residual pressure in the gauge, and the pressure gauge is damaged. 4. How to determine the range of the pressure gauge? answer: The measuring range of the instrument is determined according to the size of the pressure being measured. For elastic pressure gauges, when selecting the pressure gauge range, sufficient room must be left based on the properties of the medium being measured. Generally speaking, when measuring stable pressure, the maximum working pressure should not exceed 2/3 of the range. ； When measuring pulsating pressure, the maximum working pressure should not exceed 1/2 of the measuring range. ； When measuring high pressure, the maximum working pressure should not exceed 3/5 of the measuring range. ； To ensure accuracy, the minimum working pressure should not be less than 1/3 of the measuring range. 5. When measuring steam pressure, what are the special requirements for the installation of pressure gauges? answer: When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1. 1atm=1013300 Pa=10332mmH2O=759.93mmHg1.0332kgf/cm2. 1 kgf/cm2=98067Pa=10000mmH2O=735.5mmHg=0.9678atm. 2. The value of pressure is from * * Starting from the unit value of the pressure reproduced by the reference instrument, it is gradually transmitted to various types of pressure instruments for work through standard instruments and calibration methods at all levels. Working instruments are generally calibrated by direct comparison. 3. The spring bend causes permanent deformation and loses elasticity. ； The pointer and the central axis are loose, or the pointer is stuck ； The passage of the cock, pressure gauge connecting pipe or water trap is blocked. 4. The measuring range of the pressure gauge is generally 1.5 to 3 times the working pressure of the equipment, preferably 2 times. 5. When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1. 1atm＝（1013300）Pa＝（10330）mmH2O＝（760）mmHg（1.0332）kgf/cm2. 1 kgf/cm2 = (98070) Pa = (10000) mmH2O = (735.6) mmHg = (0.9678) atm. 2. Benchmark - first-class standard - second-class standard - third-class standard - working instruments and meters 3. The spring bend causes permanent deformation and loses elasticity. ； The pointer and the central axis are loose, or the pointer is stuck ； The passage of the cock, pressure gauge connecting pipe or water trap is blocked. 4. The measuring range of the pressure gauge is generally 1.5 to 3 times the working pressure of the equipment, preferably 2 times. 5. When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging it.
1. 1atm=（1.01325×105）Pa=（10332.3）mmH2O=（760）mmHg=（1.03323）kgf/cm2; 1 kgf/cm2=（9.80665×104）Pa=（10000）mmH2O=（735.562）mmHg=（0.967841）atm 2. In order to ensure the uniformity of pressure measurement values, in* * The metrology department preserves my country's pressure benchmark, which is the highest domestic standard for pressure measurement. At the same time, it is compared with the national defense pressure benchmark to achieve consistency in magnitude. The pressure magnitude is from * * The reference device reproduces the unit value of the pressure, and then passes it step by step to various types of pressure instruments for work through standard devices and calibration methods at all levels. 3. The pointer is bent, the hairspring torque is insufficient, the pointer is loose, the transmission gear has friction, the spring tube is clogged, and there is residual pressure in the meter. 4. The measuring range of the instrument is determined according to the size of the pressure being measured. For elastic pressure gauges, when selecting the pressure gauge range, sufficient room must be left based on the properties of the medium being measured. Generally speaking, when measuring stable pressure, the maximum working pressure should not exceed 2/3 of the range. ； When measuring pulsating pressure, the maximum working pressure should not exceed 1/2 of the measuring range. ； When measuring high pressure, the maximum working pressure should not exceed 3/5 of the measuring range. ； In order to ensure accuracy, the minimum working pressure should not be less than 1/3 of the measuring range. 5. When measuring steam pressure, a ring tube should be installed at the lower end of the pressure gauge to transmit pressure through steam condensate to prevent high-temperature steam from directly entering the gauge and damaging the gauge.