The atmospheric pressure in the industrial field is usually based on standard atmospheric pressure (Standard Atmospheric Pressure), and its value is 101325 Pa ska (Pa). The following is a detailed explanation based on physical principles and industrial practice:
1. Core Value and Unit Conversion
- standard Atmospheric Pressure Definition
- numerical: 101325 Pa (Pascal), equivalent to 101.32 5千帕(kPa) or 0.101325 MPa (MPa).
- physical meaning: Represents the average pressure exerted by the atmosphere on a unit area at sea level, a temperature of 15°C, and a humidity of 0%.
- Conversion of common industrial units
- bar (bar): 1 bar = 100000 Pa, so the standard atmospheric pressure is about 1.01325 bar.
- Pound-force per square inch (psi): 1 psi & asymp; 6894.76 Pa, so the standard atmospheric pressure is about 14.696 psi.
Practical Applications in 2. Industrial Scenarios
- conventional Industrial Environment
- numerical range in the plains below 500 meters above sea level, the atmospheric pressure is usually stable between 98000 Pa and 103000 Pa.
- Application Scenarios: Such as ordinary plant ventilation, pneumatic tool drive, etc., equipment design is generally calibrated according to standard atmospheric pressure (101325 Pa).
- Special industrial scenarios
- high pressure environment: Such as high-pressure reactor, deep-sea simulation device, the operating pressure may reach several megapascals (MPa), far exceeding atmospheric pressure.
- Vacuum environment such as electronic device packaging, vacuum drying oven, the pressure may be lower than 1000 Pa (low vacuum) or even 0.1 Pa (high vacuum).
Influencing factors of 3. atmospheric pressure
- elevation
- influence law for every 100 meters above sea level, the atmospheric pressure drops by about 1200 Pa.
- Examples at an altitude of 3000 meters, the atmospheric pressure may drop below 70000 Pa, and altitude compensation design for air compressors and other equipment is required.
- Temperature and Humidity
- temperature effect for every 1 ℃ increase in air temperature, the atmospheric pressure decreases by about 40 Pa (density decreases due to air expansion).
- Humidity effect the total pressure of high humidity air may be slightly higher than that of dry air (but the difference is usually less than 1%) due to the increase of water vapor partial pressure.
4. Industrial Measurement and Control
- pressure measuring instrument
- accuracy range: The accuracy of industrial-grade pressure gauges is usually ± 0.5 to ± 1%, which can meet the needs of most scenarios.
- Typical equipment such as diaphragm pressure gauge, digital pressure sensor, range covering 0 to 1.6 MPa(16 times atmospheric pressure).
- pressure control system
- automatic adjustment through proportional valve, frequency converter and other equipment, the system pressure can be kept stable at the set value (such as within ± 100 Pa).
- Security Protection equipped with pressure switch and safety valve, automatic pressure relief when the pressure exceeds 1.2 times the rated value.
Conclusion the atmospheric pressure in the industrial field is usually based on 101325 Pa, but the actual value may fluctuate due to altitude, temperature and other factors. In the equipment selection and process design, it is necessary to calibrate and compensate the pressure requirements of the specific scene to ensure the stable operation of the system.
