Conversion between pressure units such as MPa, bar, kgf/cm2, mmH2O, and mmHg

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In physics, Force and Pressure are two distinct concepts. Pressure refers to the force exerted per unit area of a substance, and it is used to indicate the effect produced by that force. The greater the pressure, the more pronounced the effect of that force. The formula for calculating pressure is: P = F/S, where P represents pressure, F represents the vertical force (pressure applied), and S represents the area over which the force is applied. In practical engineering, the mechanical concept of force known as \"pressure\" is rarely used; the term \"pressure\" is usually replaced by \"stress\". Translating Pressure as \"pressure\" does not cause any ambiguity. If there is any doubt, one can simply look at the unit – Newtons or Pascals make it clear at a glance. It is expected that this problem will persist for a long time; as for whether it can be fixed or when it will be fixed, I really have no idea. Similar (mistake) situations don’t hinder work; the more you encounter them, the more accustomed you become. 1. Common units for pressure measurement and their conversions: In the International System of Units, the unit of pressure is pascal, abbreviated as Pa, which is equivalent to Newton per square meter (N/m2). This unit was named in honor of the renowned French physicist Blaise Pascal. Other commonly used units of pressure include kilopascals (kPa), megapascals (MPa), psi (pounds per square inch, lb/in2), bars, standard atmospheres (atm), millimeters of mercury (mmHg), Torr, inches of mercury (inHg), and millimeters of water column (mmH2O), among others. Previously, millibars were commonly used in meteorology, but they were later replaced by the equivalent international unit of hectopascals. According to the conventions of the World Meteorological Organization, the unit for air pressure can be either \"hectopascals (hPa)\\" or \"millibars (mbar)\\"; both are used concurrently for now, with hectopascals ultimately becoming the standard unit, abbreviated as hPa. In China, the unit \"kilogram\" (kilogram-force or kilogram-pressure) is also commonly used to express pressure, with the unit being \"kgf/cm2\", which indicates one kilogram-force acting on an area of one square centimeter. 2. Conversions of pressure units such as MPa, bar, kg, etc. ◆ Since the unit of Pascal (Pa) is too small – even a sunflower seed on a table creates a pressure of over 10 Pa – engineering applications use multiples of this unit: 1 MPa (megapascal) = 1000 kPa (kilopascal) = 1,000,000 Pa (pascal). ◆ psi (Pounds per square inch) is the pressure unit commonly used in countries in Europe and America. 1 psi ≈ 6.895 kPa (kilopascals) ≈ 6894.757 Pa (pascals). The bar is part of the International System of Units (SI) and is commonly used in industrial and engineering fields. 1 bar = 0.1 MPa = 100 kPa = 100,000 Pa. ◆ The standard atmosphere (atm) is a common unit used to express atmospheric pressure. 1 atm (standard atmospheric pressure) = 760 mmHg (millimeters of mercury) = 101.325 kPa (kilopascals) = 101325 Pa (pascals). ◆ Millimeters of mercury refer to millimeters of a mercury column; it is a unit used to express pressure values based on the height of a mercury column in millimeters. 1 mmHg (millimeters of mercury) = 1 Torr = 0.1333224 kPa (kilopascals) ≈ 133.322 Pa (pascals). ◆ inHg (inches of mercury), based on millimeters of mercury; a unit used in Europe and the United States. 1 inHg (inches of mercury) = 3.3863882 kPa (kilopascals) ≈ 3386.388 Pa (pascals). ◆ mmH2O, referenced to millimeters of mercury. 1 mmH2O (millimeters of water column) ≈ 9.807 Pa (pascals). ◆ Kilogram force per square centimeter (kgf/cm2) represents the force exerted by one kilogram of weight on an area of one square centimeter; this unit is commonly used in China. 1 kgf/cm2 (kilograms) ≈ 0.098 MPa (megapascals) ≈ 98.0665 kPa (kilopascals) ≈ 98066.5 Pa (pascals)