What is the difference between positive pressure and normal pressure?
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What is the difference between positive pressure and atmospheric pressure? What are the approximate values of positive pressure and atmospheric pressure?
Positive pressure is relative to negative pressure; it indicates that the pressure inside a container is higher than the atmospheric pressure outside, while negative pressure is the opposite. Atmospheric pressure refers to the pressure of the atmosphere, and containers that are in communication with the atmosphere are generally considered atmospheric-pressure containers.
Atmospheric pressure is the normal pressure; pressures higher than this are considered positive pressures. Done: lol
Positive pressure is pressurized, that is, it is greater than atmospheric pressure； At normal pressure, it is open and connected to the atmosphere. If it is a container design, it falls under the category of pressure vessels; otherwise, it does not.
Positive pressure is relative to atmospheric pressure; a value that is higher than atmospheric pressure is considered positive pressure. . Atmospheric pressure refers to the pressure of the atmosphere, and containers that are in communication with the atmosphere are generally considered atmospheric-pressure containers.
Positive pressure refers to an absolute pressure that is higher than atmospheric pressure, while normal pressure means that the absolute pressure is equal to atmospheric pressure.
Then why is the pipeline pressure at normal pressure and temperature in process design set at 0.05 Mpa?
I think normal pressure refers to what we commonly call standard atmospheric pressure, while positive pressure is a pressure that is higher than standard atmospheric pressure. Atmospheric pressure is 1 kilogram-force, while positive pressure can be three, four kilogram-forces or even higher.
Atmospheric pressure refers to the local air pressure, and specific values are available for it. There is no exact value for positive pressure; it simply indicates that the pressure is higher than atmospheric pressure.
1 standard atmosphere = 760 millimeters of mercury = 76 centimeters of mercury = 1.013×105 pascals = 10.336 meters of water column. Positive pressure refers to a situation where the absolute pressure is higher than atmospheric pressure, while normal pressure means that the absolute pressure is equal to atmospheric pressure; in other words, normal pressure is simply atmospheric pressure. An open container is a container under normal pressure.