The common saying on air compressors, "8 kilograms of pressure "≈ 8 bar, is a conventional expression in engineering.
Detailed Explanation of Unit Conversion
1. Engineering Approximate Conversion (Most commonly used
In the air compressor industry and engineering sites, 1 kilogram of pressure is approximately equal to 1 bar. Therefore:
The conversion result of the engineering statement in the table: 8 kilograms of pressure ≈ 8 bar; 0.8 MPa= 8 bar
This approximate relationship is widely used, with an error within ±2%, fully meeting the requirements of engineering applications.
2. Precise conversion relationship
Strictly speaking from a physical perspective:
1 bar = 100,000 Pa (International unit)
1 kgf/cm² (engineering "kilogram") = 98,066.5 Pa
1 bar ≈ 1.0197 kgf/cm²
1 kgf/cm² ≈ 0.9807 bar
So, strictly calculate:
A pressure of 8 kilograms = 8 × 0.9807 bar ≈ 7.85 bar
However, in the actual labeling of air compressors, 8 kilograms is calibrated based on 8 bar, which is directly regarded as equal in engineering.
3. Common Pressure Unit Comparison Table
Table unit conversion relationship: 1 bar= 0.1 MPa= 1 kilogram pressure ≈ 14.5 psi; 1 MPa= 10 bar= 10 kilograms pressure; 1 kgf/cm²≈ 0.98 bar
Why is there the term "kilogram"?
"Kilogram pressure" is actually a common term in engineering. Strictly speaking, it refers to kilogram force per square centimeter (kgf/cm²), that is, the pressure produced when 1 kilogram of force acts on an area of 1 square centimeter. Because it is very close to the bar value, the domestic air compressor industry simplifies its use to "1 kilogram =1 bar".
Summary: The "8 kilograms pressure "mentioned on the air compressor is actually 8 bar (or 0.8 MPa) in engineering, which can be directly understood as a 1:1 ratio.
If you are interested, you can learn how to quickly convert the pressure units of air compressors, such as MPa, bar, and psi. The nominal units of equipment may vary in different countries. In addition, it is also worth knowing what the general working pressure range of an air compressor is. Different application scenarios have significant differences in pressure requirements.